Download Identification of Areas of High Conservation Value in South Australia

Conserving Marine Biodiversity in South Australia
- Part 2 - Identification of areas of high
conservation value in South Australia
K S Edyvane
May 1999
ISBN 0 7308 5238 5
No 39
The recommendations given in this publication are based on the best available information at the
time of writing. The South Australian Research and Development Institute (SARDI) makes no
warranty of any kind expressed or implied concerning the use of technology mentioned in this
publication.
© SARDI. This work is copyright. Apart of any use as permitted under the Copyright Act 1968, no
part may be reproduced by any process without prior written permission from the publisher.
SARDI is a group of the Department of Primary Industries and Resources
CONTENTS – PART TWO
PAGE
NUMBER
CONTENTS
INTRODUCTION
1
1.1
Introduction
-----------------------------------------
i
The Hierarchical Nature of Biodiversity
-------------------------------------------------1.2
Classifying Marine Ecosystems – Bioregionalisation ---------------------------------------------1.3
Defining a Marine Bioregional Planning Framework for South Australia----------------------1.4
IMCRA – A National Template for Marine Biodiversity and Ecosystem Management------1.5
‘Province’ or Large Marine Ecosystem Regionalisation------------------------------------------1.6
‘Bioregion’ or Ecosystem – Level Regionlisation -------------------------------------------------1.7
‘Biounit’ or Habitat – Level Regionalisation
-------------------------------------------------1.8
Criteria for Identifying Areas of Conservation Significance -------------------------------------APPENDIX ONE
--------------------------------------------------
i
iii
iii
vi
vii
viii
viii
xvi
xviii
EYRE COAST REGION
-----------------------------------------
1
MARINE BIOGEOGRAPHY
-----------------------------------------
2
The Eyre Coast
-------------------------------------------------Biogeography of the Eyre Coast
-------------------------------------------------Oceanography ----------------------------------------------------------------------------------------Wave Climate
-------------------------------------------------Water Temperature and Salinity ---------------------------------------------------------------------Currents and Upwellings -----------------------------------------------------------------------------Climate -------------------------------------------------------------------------------------------------Coastal Geomorphology and Landforms--------------------------------------------------------Biology--------------------------------------------------------------------------------------------------Intertidal Ecology--------------------------------------------------------------------------------------Subtidal Ecology---------------------------------------------------------------------------------------Fish ------------------------------------------------------------------------------------------------------Seabirds -------------------------------------------------------------------------------------------------Marine Mammals ---------------------------------------------------------------------------------------
2
2
3
3
3
3
4
4
5
5
5
8
8
8
MARINE CONSERVATION VALUES -----------------------------------------------
9
1
1.1
1.2
2
2.1
2.2
3
9
9
1
1.1
2
2.1
2.2
2.3
3
4
5
5.1
5.2
5.3
5.4
5.5
Significant Biological and Physical Features ------------------------------------------------------Biological-----------------------------------------------------------------------------------------------Physical -------------------------------------------------------------------------------------------------Significant Cultural and Historical Features ---------------------------------------------------Aboriginal ----------------------------------------------------------------------------------------------European------------------------------------------------------------------------------------------------Current Conservation Status of the Eyre Coast -----------------------------------------------------
12
12
14
15
I
NULLARBOR BIOUNIT --------------------------------------------------------MARINE BIOGEOGRAPHY -----------------------------------------------------------
16
16
1
2
3
16
16
16
17
17
17
19
20
20
21
21
22
22
Oceanography ----------------------------------------------------------------------------------------Geology and Coastal Geomorphology------------------------------------------------------------Biology---------------------------------------------------------------------------------------------------
MARINE CONSERVATION VALUES ----------------------------------------------1
1.1
1.2
2
2.1
2.2
2.3
2.4
2.5
Significant Biological and Physical Features ------------------------------------------------------Biological-----------------------------------------------------------------------------------------------Physical -------------------------------------------------------------------------------------------------Other Values -------------------------------------------------------------------------------------------Commercial Fisheries ---------------------------------------------------------------------------------Mariculture ---------------------------------------------------------------------------------------------Recreation and Tourism ------------------------------------------------------------------------------Scientific Research and Education ------------------------------------------------------------------Adjacent Land Use -------------------------------------------------------------------------------------
11
CONTENTS – PART TWO
PAGE
NUMBER
CONTENTS
2.5
Significant Cultural and Historical Features
--------------------------------------------------
22
3
4
Current Conservation Status of the Nullarbor Biounit ---------------------------------------Areas of High Conservation Value in the Nullarbor Biounit ---------------------------------
22
23
II
WAHGUNYAH BIOUNIT
MARINE BIOGEOGRAPHY
-----------------------------------------------------------------------------------
1
2
3
----------------------------------------------------------------------------------------------------------------------------------------------------
Oceanography
Geology and Coastal Geomorphology
Biology
MARINE CONSERVATION VALUES
1
1.1
1.2
2
2.1
2.2
2.3
2.4
2.5
2.6
3
4
-----------------------------------------
Significant Biological and Physical Features -------------------------------------------------Biological
-------------------------------------------------Physical
-------------------------------------------------Other Values
-------------------------------------------------Commercial Fisheries
-------------------------------------------------Mariculture
-------------------------------------------------Recreation and Tourism
-------------------------------------------------Scientific Research and Education
-------------------------------------------------Adjacent Land Use
-------------------------------------------------Significant Cultural and Historical Features
-------------------------------------------------Current Conservation Status of the Wahgunyah Biounit ------------------------------------Areas of High Conservation Value in the Wahgunyah Biounit-------------------------------
III
FOWLERS BIOUNIT
MARINE BIOGEOGRAPHY
-----------------------------------------------------------------------------------
1
2
3
----------------------------------------------------------------------------------------------------------------------------------------------------
Oceanography
Geology and Coastal Geomorphology
Biology
MARINE CONSERVATION VALUES
1
1.1
1.2
2
2.1
2.2
2.3
2.4
2.5
2.6
3
4
-----------------------------------------
Significant Biological and Physical Features -------------------------------------------------Biological
-------------------------------------------------Physical
-------------------------------------------------Other Values
-------------------------------------------------Commercial Fisheries
-------------------------------------------------Mariculture
-------------------------------------------------Recreation and Tourism
-------------------------------------------------Scientific Research and Education
-------------------------------------------------Adjacent Land Use
-------------------------------------------------Significant Cultural and Historical Features
-------------------------------------------------Current Conservation Status of the Fowlers Biounit ------------------------------------------Areas of High Conservation Value in the Fowlers Biounit ------------------------------------
24
24
24
24
24
25
25
25
25
25
25
26
26
26
26
26
27
27
28
28
28
28
28
29
29
29
29
29
29
30
30
30
31
31
31
32
CONTENTS – PART TWO
PAGE
NUMBER
CONTENTS
IV
STREAKY AND NUYTS BIOUNITS -----------------------------------MARINE BIOGEOGRAPHY
----------------------------------------1
2
3
----------------------------------------------------------------------------------------------------------------------------------------------------
33
33
33
34
-----------------------------------------
35
Significant Biological and Physical Features -------------------------------------------------Biological
-------------------------------------------------Physical
-------------------------------------------------Other Values
-------------------------------------------------Commercial Fisheries
-------------------------------------------------Mariculture
-------------------------------------------------Recreation and Tourism
-------------------------------------------------Scientific Research and Education
-------------------------------------------------Adjacent Land Use
-------------------------------------------------Significant Cultural and Historical Features
-------------------------------------------------Current Conservation Status of the Streaky and Nuyts Biounit ----------------------------Streaky Biounit
-------------------------------------------------Nuyts Biounit
-------------------------------------------------Areas of High Conservation Value in the Streaky and Nuyts Biounit ---------------------Streaky Biounit
-------------------------------------------------Nuyts Archipelago
--------------------------------------------------
35
35
37
38
38
39
40
40
40
41
42
42
42
42
42
43
Oceanography
Geology and Coastal Geomorphology
Biology
MARINE CONSERVATION VALUES
1
1.1
1.2
2
2.1
2.2
2.3
2.4
2.5
2.6
3
3.1
3.2
4
4.1
4.2
33
V
YANERBIE BIOUNIT
MARINE BIOGEOGRAPHY
-----------------------------------------------------------------------------------
1
2
3
----------------------------------------------------------------------------------------------------------------------------------------------------
Oceanography
Geology and Coastal Geomorphology
Biology
MARINE CONSERVATION VALUES
-----------------------------------------
45
45
45
45
45
1
1.1
1.2
2
2.1
2.2
2.3
2.4
2.5
2.6
3
Significant Biological and Physical Features -------------------------------------------------Biological
-------------------------------------------------Physical
-------------------------------------------------Other Values
-------------------------------------------------Commercial Fisheries
-------------------------------------------------Aquaculture
-------------------------------------------------Recreation and Tourism
-------------------------------------------------Scientific Research and Education
-------------------------------------------------Adjacent Land Use
-------------------------------------------------Significant Cultural and Historical Features
-------------------------------------------------Current Conservation Status of the Yanerbie Biounit -----------------------------------------
46
46
46
48
48
48
48
49
49
49
49
49
4
Areas of High Conservation Value in the Yanerbie Biounit ----------------
50
CONTENTS – PART TWO
CONTENTS
--------------------------------- PAGE
NUMBER
VI
NEWLAND BIOUNIT
MARINE BIOGEOGRAPHY
-----------------------------------------------------------------------------------
1
2
3
----------------------------------------------------------------------------------------------------------------------------------------------------
Oceanography
Geology and Coastal Geomorphology
Biology
MARINE CONSERVATION VALUES
1
1.1
1.2
2
2.1
2.2
2.3
2.4
2.5
2.6
3
4
-----------------------------------------
Significant Biological and Physical Features -------------------------------------------------Biological
-------------------------------------------------Physical
-------------------------------------------------Other Values
-------------------------------------------------Commercial Fisheries
-------------------------------------------------Mariculture
-------------------------------------------------Recreation and Tourism
-------------------------------------------------Scientific Research and Education
-------------------------------------------------Adjacent Land Use
-------------------------------------------------Significant Cultural and Historical Features
-------------------------------------------------Current Conservation Status of the Newland Biounit-----------------------------------------Areas of High Conservation Value in the Newland Biounit -----------------------------------
VII
SHERINGA AND FLINDERS BIOUNITS ----------------------------MARINE BIOGEOGRAPHY
----------------------------------------1
2
3
Oceanography
Geology and Coastal Geomorphology
Biology
MARINE CONSERVATION VALUES
1
1.1
1.2
2
2.1
2.2
2.3
2.4
2.5
2.6
3
3.1
3.2
4
4.1
4.2
----------------------------------------------------------------------------------------------------------------------------------------------------
-----------------------------------------
Significant Biological and Physical Features -------------------------------------------------Biological
-------------------------------------------------Physical
-------------------------------------------------Other Values
-------------------------------------------------Commercial Fisheries
-------------------------------------------------Aquaculture
-------------------------------------------------Recreation and Tourism
-------------------------------------------------Scientific Research and Education
-------------------------------------------------Adjacent Land Use
-------------------------------------------------Significant Cultural and Historical Features
-------------------------------------------------Current Conservation Status of the Sheringa and Flinders Biounits ----------------------Sheringa Biounit
-------------------------------------------------Flinders Biounit
-------------------------------------------------Areas of High Conservation Value in the Sheringa and Flinders Biounits----------------Sheringa Biounit
-------------------------------------------------Flinders Biounit
--------------------------------------------------
51
51
51
51
51
52
52
52
53
53
53
54
54
54
54
55
55
55
56
56
56
56
57
57
57
57
59
59
59
60
60
61
61
62
62
62
62
63
63
63
CONTENTS – PART TWO
PAGE
NUMBER
CONTENTS
VIII
DOUGLAS BIOUNIT
MARINE BIOGEOGRAPHY
-----------------------------------------------------------------------------------
1
2
3
----------------------------------------------------------------------------------------------------------------------------------------------------
Oceanography
Geology and Coastal Geomorphology
Biology
MARINE CONSERVATION VALUES
1
1.1
1.2
2
2.1
2.2
2.3
2.4
2.5
2.6
3
4
-----------------------------------------
Significant Biological and Physical Features -------------------------------------------------Biological
-------------------------------------------------Physical
-------------------------------------------------Other Values
-------------------------------------------------Commercial Fisheries
-------------------------------------------------Aquaculture
-------------------------------------------------Recreation and Tourism
-------------------------------------------------Scientific Research and Education
-------------------------------------------------Adjacent Land Use
-------------------------------------------------Significant Cultural and Historical Features
-------------------------------------------------Current Conservation Status of the Douglas Biounit------------------------------------------Areas of High Conservation Value in the Douglas Biounit ------------------------------------
IX
WHIDBEY BIOUNIT
MARINE BIOGEOGRAPHY
-----------------------------------------------------------------------------------
1
2
3
----------------------------------------------------------------------------------------------------------------------------------------------------
Oceanography
Geology and Coastal Geomorphology
Biology
MARINE CONSERVATION VALUES
1
1.1
1.2
2
2.1
2.2
2.3
2.4
2.5
2.6
3
4
-----------------------------------------
Significant Biological and Physical Features -------------------------------------------------Biological
-------------------------------------------------Physical
-------------------------------------------------Other Values
-------------------------------------------------Commercial Fisheries
-------------------------------------------------Aquaculture
-------------------------------------------------Recreation and Tourism
-------------------------------------------------Scientific Research
-------------------------------------------------Adjacent Land Use
-------------------------------------------------Significant Cultural and Historical Features
-------------------------------------------------Current Conservation Status of the Whidey Biounit ------------------------------------------Areas of High Conservation Value in the Whidbey Biounit-----------------------------------
SPENCER GULF REGION
65
65
65
65
65
66
66
66
68
68
68
68
70
70
70
71
71
71
72
72
72
72
73
73
73
73
75
75
75
76
76
76
76
77
77
77
-------------------------------------------
79
MARINE BIOGEOGRAPHY
-----------------------------------------
1
1.1
2
2.1
2.2
2.3
3
4
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
80
80
80
80
80
81
81
81
81
Spencer Gulf
Biogeography of the Spencer Gulf
Oceanography
Wave Climate
Water Temperature and Salinity
Currents
Climate
Coastal Geomorphology and Landforms
CONTENTS – PART TWO
PAGE
NUMBER
CONTENTS
5
5.1
5.2
5.3
5.4
5.5
5.6
5.7
Biology
General Marine Ecology
Intertidal Ecology
Subtidal Ecology
Seagrass Ecology
Fish
Marine Mammals
Seabirds
MARINE CONSERVATION VALUES
1
1.1
1.2
2
2.1
2.2
3
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
82
82
82
83
84
85
85
86
-----------------------------------------
87
87
87
89
89
89
90
91
Significant Biological and Physical Features -------------------------------------------------Biological
-------------------------------------------------Physical
-------------------------------------------------Significant Cultural and Historical Features -------------------------------------------------Aboriginal
-------------------------------------------------European
-------------------------------------------------Current Conservation Status of the Spencer Gulf ----------------------------------------------
X
JUSSIEU BIOUNIT
MARINE BIOGEOGRAPHY
-----------------------------------------------------------------------------------
1
2
3
----------------------------------------------------------------------------------------------------------------------------------------------------
Oceanography
Geology and Coastal Geomorphology
Biology
MARINE CONSERVATION VALUES
1
1.1
1.2
2
2.1
2.2
2.3
2.4
2.5
2.6
3
4
-----------------------------------------
Significant Biological and Physical Features -------------------------------------------------Biological
-------------------------------------------------Physical
-------------------------------------------------Other Values
-------------------------------------------------Commercial Fisheries
-------------------------------------------------Aquaculture
-------------------------------------------------Recreation and Tourism
-------------------------------------------------Scientific Research
-------------------------------------------------Adjacent Land Use
-------------------------------------------------Significant Cultural and Historical Features
-------------------------------------------------Current Conservation Status of the Jussieu Biounit-------------------------------------------Areas of High Conservation Value in the Jussieu Biounit
92
92
92
92
93
94
94
94
97
97
97
98
99
100
100
101
102
102
CONTENTS – PART TWO
PAGE
NUMBER
CONTENTS
XI
DUTTON BIOUNIT
MARINE BIOGEOGRAPHY
-----------------------------------------------------------------------------------
104
1
Oceanography
-------------------------------------------------2
Geology and Coastal Geomorphology
-------------------------------------------------3
Biology
-------------------------------------------------MARINE CONSERVATION VALUES
-------------------------------------------------1
Significant Biological and Physical Features -------------------------------------------------1.1
Biological
-------------------------------------------------1.2
Physical
-------------------------------------------------2
Other Values
-------------------------------------------------2.1
Commercial Fisheries
-------------------------------------------------2.2
Aquaculture
-------------------------------------------------2.3
Recreation and Tourism
-------------------------------------------------2.4
Scientific Research
-------------------------------------------------2.5
Adjacent Land Use
-------------------------------------------------2.6
Significant Cultural and Historical Features
-------------------------------------------------3
Current Conservation Status of the Dutton Biounit --------------------------------------------
104
104
104
104
104
104
104
104
105
105
105
105
106
106
106
106
4
106
Areas of High Conservation Value in the Dutton Biounit -------------------
XII
FRANKLIN BIOUNIT
MARINE BIOGEOGRAPHY
-----------------------------------------------------------------------------------
1
2
3
----------------------------------------------------------------------------------------------------------------------------------------------------
Oceanography
Geology and Coastal Geomorphology
Biology
MARINE CONSERVATION VALUES
1
1.1
1.2
2
2.1
2.2
2.3
2.4
2.5
2.6
3
4
-----------------------------------------
Significant Biological and Physical Features -------------------------------------------------Biological
-------------------------------------------------Physical
-------------------------------------------------Other Values
-------------------------------------------------Commercial Fisheries
-------------------------------------------------Aquaculture
-------------------------------------------------Recreation and Tourism
-------------------------------------------------Scientific Research
-------------------------------------------------Adjacent Land Use
-------------------------------------------------Significant Cultural and Historical Features
-------------------------------------------------Current Conservation Status of the Franklin Biounit-----------------------------------------Areas of High Conservation Value in the Franklin Biounit -----------------------------------
107
107
107
107
108
108
108
108
109
109
109
110
111
111
111
111
111
111
CONTENTS – PART TWO
PAGE
NUMBER
CONTENTS
XIII
YONGA BIOUNIT
MARINE BIOGEOGRAPHY
-----------------------------------------------------------------------------------
1
2
3
----------------------------------------------------------------------------------------------------------------------------------------------------
113
113
113
113
-----------------------------------------
114
Significant Biological and Physical Features -------------------------------------------------Biological
-------------------------------------------------Physical
-------------------------------------------------Other Values
-------------------------------------------------Commercial Fisheries
-------------------------------------------------Aquaculture
-------------------------------------------------Recreation and Tourism
-------------------------------------------------Scientific Research
-------------------------------------------------Adjacent Land Use
-------------------------------------------------Significant Cultural and Historical Features
-------------------------------------------------Current Conservation Status of the Yonga Biounit--------------------------------------------Areas of High Conservation Value in the Yonga Biounit --------------------------------------
114
114
116
116
116
117
117
118
118
118
118
118
Oceanography
Geology and Coastal Geomorphology
Biology
MARINE CONSERVATION VALUES
1
1.1
1.2
2
2.1
2.2
2.3
2.4
2.5
2.6
3
4
XIV
WINNINOWIE BIOUNIT
MARINE BIOGEOGRAPHY
-----------------------------------------------------------------------------------
1
2
3
----------------------------------------------------------------------------------------------------------------------------------------------------
Oceanography
Geology and Coastal Geomorphology
Biology
MARINE CONSERVATION VALUES
1
1.1
1.2
2
2.1
2.2
2.3
2.4
2.5
2.6
3
4
-----------------------------------------
Significant Biological and Physical Features -------------------------------------------------Biological
-------------------------------------------------Physical
-------------------------------------------------Other Values
-------------------------------------------------Commercial Fisheries
-------------------------------------------------Aquaculture
-------------------------------------------------Recreation and Tourism
-------------------------------------------------Scientific Research
-------------------------------------------------Adjacent Land Use
-------------------------------------------------Significant Cultural and Historical Features
-------------------------------------------------Current Conservation Status of the Winninowie Biounit-------------------------------------Areas of High Conservation Value in the Winninowie Biounit-------------------------------
113
120
120
120
120
120
121
121
121
123
124
124
124
125
125
125
125
125
126
CONTENTS – PART TWO
PAGE
NUMBER
CONTENTS
XV
TIPARRA BIOUNIT
MARINE BIOGEOGRAPHY
-----------------------------------------------------------------------------------
1
2
3
----------------------------------------------------------------------------------------------------------------------------------------------------
Oceanography
Geology and Coastal Geomorphology
Biology
MARINE CONSERVATION VALUES
-----------------------------------------
1
1.1
1.2
----------------------------------------------------------------------------------------------------------------------------------------------------
Significant Biological and Physical Features
Biological
Physical
MARINE CONSERVATION VALUES
2
2.1
2.2
2.3
2.4
2.5
2.6
3
4
-----------------------------------------
Other Values
-------------------------------------------------Commercial Fisheries
-------------------------------------------------Aquaculture
-------------------------------------------------Recreation and Tourism
-------------------------------------------------Scientific Research and Education
-------------------------------------------------Adjacent Land Use
-------------------------------------------------Significant Cultural and Historical Features
-------------------------------------------------Current Conservation Status of the Tiparra Biounit ------------------------------------------Areas of High Conservation Value in the Tiparra Biounit ------------------------------------
XVI
WARDANG BIOUNITS
MARINE BIOGEOGRAPHY
-----------------------------------------------------------------------------------
1
2
3
----------------------------------------------------------------------------------------------------------------------------------------------------
Oceanography
Geology and Coastal Geomorphology
Biology
MARINE CONSERVATION VALUES
1
1.1
1.2
2
2.1
2.2
2.3
2.4
2.5
2.6
3
4
-----------------------------------------
Significant Biological and Physical Features -------------------------------------------------Biological
-------------------------------------------------Physical
-------------------------------------------------Other Values
-------------------------------------------------Commercial Fisheries
-------------------------------------------------Aquaculture
-------------------------------------------------Recreation and Tourism
-------------------------------------------------Scientific Research and Education
-------------------------------------------------Adjacent Land Use
-------------------------------------------------Significant Cultural and Historical Features
-------------------------------------------------Current Conservation Status of the Wardang Biounit ----------------------------------------Areas of High Conservation Value in Wardang Biounit---------------------------------------
127
127
127
127
127
128
128
128
128
128
128
128
129
129
130
130
130
130
130
132
132
132
132
132
133
133
133
133
133
133
134
134
135
135
135
136
136
CONTENTS – PART TWO
PAGE
NUMBER
CONTENTS
XVII
PONDALOWIE BIOUNIT
MARINE BIOGEOGRAPHY
-----------------------------------------------------------------------------------
1
2
3
----------------------------------------------------------------------------------------------------------------------------------------------------
Oceanography
Geology and Coastal Geomorphology
Biology
MARINE CONSERVATION VALUES
1
1.1
1.2
2
2.1
2.2
2.3
2.4
2.5
2.6
3
4
-----------------------------------------
Significant Biological and Physical Features -------------------------------------------------Biological
-------------------------------------------------Physical
-------------------------------------------------Other Values
-------------------------------------------------Commercial Fisheries
-------------------------------------------------Aquaculture
-------------------------------------------------Recreation and Tourism
-------------------------------------------------Scientific Research and Education
-------------------------------------------------Adjacent Land Use
-------------------------------------------------Significant Cultural and Historical Values
-------------------------------------------------Current Conservation Status of the Pondalowie Biounit -------------------------------------Areas of High Conservation Value in the Pondalowie Biounit -------------------------------
XVIII
GAMBIER BIOUNIT
MARINE BIOGEOGRAPHY
-----------------------------------------------------------------------------------
1
2
3
----------------------------------------------------------------------------------------------------------------------------------------------------
Oceanography
Geology and Coastal Geomorphology
Biology
MARINE CONSERVATION VALUES
-----------------------------------------
1
1.1
1.2
----------------------------------------------------------------------------------------------------------------------------------------------------
Significant Biological and Physical Features
Biological
Physical
MARINE CONSERVATION VALUES
2
2.1
2.2
2.3
2.4
2.5
2.6
3
4
-----------------------------------------
Other Values
-------------------------------------------------Commercial Fisheries
-------------------------------------------------Aquaculture
-------------------------------------------------Recreation and Tourism
-------------------------------------------------Scientific Research
-------------------------------------------------Adjacent Land Use
-------------------------------------------------Significant Cultural and Historical Features
-------------------------------------------------Current Conservation Status of the Gambier Biounit-----------------------------------------Areas of High Conservation Value in the Gambier Biounit-----------------------------------
137
137
137
137
137
138
138
138
138
138
138
139
139
140
140
140
140
141
142
142
142
142
142
142
142
142
143
143
143
143
144
144
144
144
144
144
145
CONTENTS – PART TWO
PAGE
NUMBER
CONTENTS
GULF OF ST VINCENT – FLEURIEU PENINSULA REGION ------------------
146
MARINE BIOGEOGRAPHY
-----------------------------------------
1
1.1
Gulf St Vincent – Fleurieu Peninsula
Biogeography of Gulf St Vincent
- Fleurieu Peninsula
Oceanography
Wave Climate
Water Temperature and Salinity
Currents
Climate
Coastal Geomorphology and Landforms
Biology
General Ecology
Subtidal Ecology
Seagrass Ecology
Fish
Marine Mammals
--------------------------------------------------
147
147
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
147
148
148
148
148
148
149
150
150
151
152
153
153
MARINE CONSERVATION VALUES
-----------------------------------------
154
154
154
156
156
156
156
157
2
2.1
2.2
2.3
3
4
5
5.1
5.2
5.3
5.4
5.5
1
1.1
1.2
2
2.1
2.2
3
Significant Biological and Physical Features -------------------------------------------------Biological
-------------------------------------------------Physical
-------------------------------------------------Significant Cultural and Historical Features -------------------------------------------------Aboriginal
-------------------------------------------------European
-------------------------------------------------Current Conservation Status of Gulf St Vincent – Fleurieu Peninsula ---------------------
XIX
STURT AND INVESTIGATOR BIOUNITS --------------------------MARINE BIOGEOGRAPHY
----------------------------------------1
2
3
Oceanography
Geology and Coastal Geomorphology
Biology
MARINE CONSERVATION VALUES
1
1.1
1.2
2
2.1
2.2
2.3
2.4
2.5
2.6
3
4
----------------------------------------------------------------------------------------------------------------------------------------------------
-----------------------------------------
Significant Biological and Physical Features -------------------------------------------------Biological
-------------------------------------------------Physical
-------------------------------------------------Other Values
-------------------------------------------------Commercial Fisheries
-------------------------------------------------Aquaculture
-------------------------------------------------Recreation and Tourism
-------------------------------------------------Scientific Research and Education
-------------------------------------------------Adjacent Land Use
-------------------------------------------------Significant Cultural and Historical Features
-------------------------------------------------Current Conservation Status of the Sturt and Investigator Biounits ----------------------Areas of High Conservation Value in the Sturt Biounits --------------------------------------
159
159
159
159
159
160
160
160
161
161
161
162
162
163
163
164
164
164
CONTENTS – PART TWO
PAGE
NUMBER
CONTENTS
XX
ORONTES BIOUNIT
MARINE BIOGEOGRAPHY
-----------------------------------------------------------------------------------
1
2
3
----------------------------------------------------------------------------------------------------------------------------------------------------
Oceanography
Geology and Coastal Geomorphology
Biology
MARINE CONSERVATION VALUES
1
1.1
1.2
2
2.1
2.2
2.3
2.4
2.5
2.6
3
4
-----------------------------------------
Significant Biological and Physical Features -------------------------------------------------Biological
-------------------------------------------------Physical
-------------------------------------------------Other Values
-------------------------------------------------Commercial Fisheries
-------------------------------------------------Aquaculture
-------------------------------------------------Recreation and Tourism
-------------------------------------------------Scientific Research and Education
-------------------------------------------------Adjacent Land Use
-------------------------------------------------Significant Cultural and Historical Features
-------------------------------------------------Current Conservation Status of the Orontes Biounit------------------------------------------Areas of High Conservation Value in the Orontes Biounit ------------------------------------
XXI
CLINTON BIOUNIT
MARINE BIOGEOGRAPHY
-----------------------------------------------------------------------------------
1
2
3
----------------------------------------------------------------------------------------------------------------------------------------------------
Oceanography
Geology and Coastal Geomorphology
Biology
MARINE CONSERVATION VALUES
1
1.1
1.2
2
2.1
2.2
2.3
2.4
2.5
2.6
3
4
-----------------------------------------
Significant Biological and Physical Features -------------------------------------------------Biological
-------------------------------------------------Physical
-------------------------------------------------Other Values
-------------------------------------------------Commercial Fisheries
-------------------------------------------------Aquaculture
-------------------------------------------------Recreation and Tourism
-------------------------------------------------Scientific Research and Education
-------------------------------------------------Adjacent Land Use
-------------------------------------------------Significant Cultural and Historical Features
-------------------------------------------------Current Conservation Status of Clinton Biounit -----------------------------------------------Areas of High Conservation Value in the Clinton Biounit-------------------------------------
166
166
166
166
166
167
167
167
167
167
167
168
169
169
170
170
170
171
172
172
172
172
172
173
173
173
176
176
176
176
177
177
178
179
179
180
CONTENTS – PART TWO
PAGE
NUMBER
CONTENTS
XXII
YANKALILLA BIOUNIT
MARINE BIOGEOGRAPHY
-----------------------------------------------------------------------------------
1
2
3
----------------------------------------------------------------------------------------------------------------------------------------------------
Oceanography
Geology and Coastal Geomorphology
Biology
MARINE CONSERVATION VALUES
1
1.1
1.2
2
2.1
2.2
2.3
2.4
2.5
2.6
3
4
-----------------------------------------
Significant Biological and Physical Features -------------------------------------------------Biological
-------------------------------------------------Physical
-------------------------------------------------Other Values
-------------------------------------------------Commercial Fisheries
-------------------------------------------------Aquaculture
-------------------------------------------------Recreation and Tourism
-------------------------------------------------Scientific Research and Education
-------------------------------------------------Adjacent Land Use
-------------------------------------------------Significant Cultural and Historical Features
-------------------------------------------------Current Conservation Status of the Yankalilla Biounit---------------------------------------Areas of High Conservation Value in the Yankalilla Biounit ---------------------------------
XXIII
ENCOUNTER BIOUNIT
MARINE BIOGEOGRAPHY
OCEANOGRAPHY
---------------------------------------------------------------------------------------------------------------------------
2
3
---------------------------------------------------------------------------------------------------
Geology and Coastal Geomorphology
Biology
MARINE CONSERVATION VALUES
1
1.1
1.2
2
2.1
2.2
2.3
2.4
2.5
2.6
3
4
-----------------------------------------
Significant Biological and Physical Features -------------------------------------------------Biological
-------------------------------------------------Physical
-------------------------------------------------Other Values
-------------------------------------------------Commercial Fisheries
-------------------------------------------------Aquaculture
-------------------------------------------------Recreation and Tourism
-------------------------------------------------Scientific Research and Education
-------------------------------------------------Adjacent Land Use
-------------------------------------------------Significant Cultural and Historical Features
-------------------------------------------------Current Conservation Status of the Encounter Biounit---------------------------------------Areas of High Conservation Value in the Encounter Biounit---------------------------------
181
181
181
181
181
182
182
182
184
184
184
185
185
187
187
188
188
189
190
190
190
190
190
191
191
191
193
194
194
195
195
196
196
197
198
198
CONTENTS – PART TWO
PAGE
CONTENTS NUMBER
KANGAROO ISLAND COAST
-------------------------------------------
199
MARINE BIOGEOGRAPHY
-----------------------------------------
1
1.1
2
2.1
2.2
2.3
3
4
5
5.1
5.2
5.3
5.4
5.5
5.6
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
199
200
200
201
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201
202
202
202
202
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204
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204
Kangaroo Island
Biogeography of Kangaroo Island
Oceanography
Wave Climate
Water Temperature and Salinity
Currents and Upwellings
Climate
Geology and Coastal Geomorphology
Biology
General Ecology
Marine Flora
Fish
Reptiles
Seabirds
Marine Mammals
MARINE CONSERVATION VALUES
1
1.1
1.2
2
2.1
2.2
3
-----------------------------------------
Significant Biological and Physical Features -------------------------------------------------Biological
-------------------------------------------------Physical
-------------------------------------------------Significant Cultural and Historical Features -------------------------------------------------Aboriginal
-------------------------------------------------European
-------------------------------------------------Current Conservation Status of the Kangaroo Island Coast----------------------------------
XXIV
NEPEAN AND BACKSTAIRS BIOUNITS ----------------------------MARINE BIOGEOGRAPHY
----------------------------------------1
2
3
Oceanography
Geology and Coastal Geomorphology
Biology
MARINE CONSERVATION VALUES
1
1.1
1.2
2
2.1
2.2
2.3
2.4
2.5
2.6
3
4
----------------------------------------------------------------------------------------------------------------------------------------------------
-----------------------------------------
Significant Biological and Physical Features -------------------------------------------------Biological
-------------------------------------------------Physical
-------------------------------------------------Other Values
-------------------------------------------------Commercial Fisheries
-------------------------------------------------Aquaculture
-------------------------------------------------Recreation and Tourism
-------------------------------------------------Scientific Research and Education
-------------------------------------------------Adjacent Land Use
-------------------------------------------------Significant Cultural and Historical Features
-------------------------------------------------Current Conservation Status of the Nepean and Backstairs Biounits ---------------------Areas of High Conservation Value in the Nepean and Backstairs Biounits----------------
205
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209
209
210
210
210
213
214
214
215
215
216
216
216
217
217
CONTENTS – PART TWO
PAGE
NUMBER
CONTENTS
XXV
GANTHEAUME BIOUNIT
MARINE BIOGEOGRAPHY
-----------------------------------------------------------------------------------
1
Oceanography
-------------------------------------------------2
Geology and Coastal Geomorphology
-------------------------------------------------3
Biology
-------------------------------------------------MARINE CONSERVATION VALUES
-------------------------------------------------1
Significant Biological and Physical Features -------------------------------------------------1.1
Biological
-------------------------------------------------1.2
Physical
-------------------------------------------------2
Other Values
-------------------------------------------------2.1
Commercial Fisheries
-------------------------------------------------2.2
Aquaculture
-------------------------------------------------2.3
Recreation and Tourism
-------------------------------------------------2.4
Scientific Research and Education
-------------------------------------------------2.5
Adjacent Land Use
-------------------------------------------------2.6
Significant Cultural and Historical Features
-------------------------------------------------3
Current Conservation Status of the Gantheaume Biounit------------------------------------4
Areas of High Conservation Value in the Gantheaume Biounit------------------------------
XXVI
CASSINI BIOUNIT
MARINE BIOGEOGRAPHY
-----------------------------------------------------------------------------------
1
2
3
----------------------------------------------------------------------------------------------------------------------------------------------------
Oceanography
Geology and Coastal Geomorphology
Biology
MARINE CONSERVATION VALUES
1
1.1
1.2
2
2.1
2.2
2.3
2.4
2.5
2.6
3
4
-----------------------------------------
Significant Biological and Physical Features -------------------------------------------------Biological
-------------------------------------------------Physical
-------------------------------------------------Other Values
-------------------------------------------------Commercial Fisheries
-------------------------------------------------Aquaculture
-------------------------------------------------Recreation and Tourism
-------------------------------------------------Scientific Research and Education
-------------------------------------------------Adjacent Land Use
-------------------------------------------------Significant Cultural and Historical Features
-------------------------------------------------Current Conservation Status of the Cassini Biounit-------------------------------------------Areas of High Conservation Value in the Cassini Biounit -------------------------------------
219
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220
220
220
220
223
223
223
224
225
225
226
226
226
227
229
229
229
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229
230
230
230
230
231
231
231
232
232
232
233
233
233
CONTENTS – PART TWO
PAGE
NUMBER
CONTENTS
SOUTH EAST COAST
MARINE BIOGEOGRAPHY
1
1.1
2
2.1
2.2
2.3
2.4
3
4
4.1
4.2
4.3
4.4
4.5
5
5.1
5.2
5.3
5.4
5.5
MARINE CONSERVATION VALUES
1
1.1
1.2
2
2.1
2.2
3
-----------------------------------------
The South East Coast
-------------------------------------------------Biogeography of the South East Coast
-------------------------------------------------Oceanography
-------------------------------------------------Wave Climate
-------------------------------------------------Water Temperature and Salinity
-------------------------------------------------Currents and Upwellings
-------------------------------------------------Groundwater Drainage
-------------------------------------------------Climate
-------------------------------------------------Coastal Geomorphology and Landforms
-------------------------------------------------Outer Dune Barrier Complexes of Younghusband Peninsula and Robe ------------------------Beach-Ridge Plains of Lacepede, Guichen and Rivoli Bays -------------------------------------Coorong and Robe Range - Woakwine Range Despressions-------------------------------------Stranded Pleistocene Barriers and Relict Coast of the Robe Range Outer Barrier ------------Tertiary Limestone Plain of the Lower South East ------------------------------------------------Biology
-------------------------------------------------General Ecology
-------------------------------------------------Subtidal Ecology
-------------------------------------------------Fish
-------------------------------------------------Seabirds
-------------------------------------------------Marine Mammals
--------------------------------------------------
-----------------------------------------
Significant Biological and Physical Features -------------------------------------------------Biological
-------------------------------------------------Physical
-------------------------------------------------Significant Cultural and Historical Features -------------------------------------------------Aboriginal
-------------------------------------------------European
-------------------------------------------------Current Conservation Status of the South East Coast -----------------------------------------
236
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236
237
237
237
257
237
238
238
238
238
238
238
239
239
239
239
240
241
241
241
241
241
242
242
243
243
243
CONTENTS – PART TWO
PAGE
NUMBER
CONTENTS
XXVII
COORONG BIOUNIT
MARINE BIOGEOGRAPHY
-----------------------------------------------------------------------------------
1
2
3
----------------------------------------------------------------------------------------------------------------------------------------------------
Oceanography
Geology and Coastal Geomorphology
Biology
MARINE CONSERVATION VALUES
1
1.1
1.2
2
2.1
2.2
2.3
2.4
2.5
2.6
3
4
-----------------------------------------
Significant Biological and Physical Features -------------------------------------------------Biological
-------------------------------------------------Physical
-------------------------------------------------Other Values
-------------------------------------------------Commercial Fisheries
-------------------------------------------------Aquaculture
-------------------------------------------------Recreation and Tourism
-------------------------------------------------Scientific Research and Education
-------------------------------------------------Adjacent Land Use
-------------------------------------------------Significant Cultural and Historical Features
-------------------------------------------------Current Conservation Status of the Coorong Biounit -----------------------------------------Areas of High Conservation Value in the Coorong Biounit -----------------------------------
XXVIII
CANUNDA BIOUNIT
MARINE BIOGEOGRAPHY
-----------------------------------------------------------------------------------
1
2
3
----------------------------------------------------------------------------------------------------------------------------------------------------
Oceanography
Geology and Coastal Geomorphology
Biology
MARINE CONSERVATION VALUES
1
1.1
1.2
2
2.1
2.2
2.3
2.4
2.5
2.6
3
4
-----------------------------------------
Significant Biological and Physical Features -------------------------------------------------Biological
-------------------------------------------------Physical
-------------------------------------------------Other Values
-------------------------------------------------Commercial Fisheries
-------------------------------------------------Aquaculture
-------------------------------------------------Recreation and Tourism
-------------------------------------------------Scientific Research and Education
-------------------------------------------------Adjacent Land Use
-------------------------------------------------Significant Cultural and Historical Features
-------------------------------------------------Current Conservation Status of the Canunda Biounit ----------------------------------------Areas of High Conservation Value in the Canunda Biounit ----------------------------------
244
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245
245
248
248
248
249
249
249
249
250
251
251
252
252
252
252
252
253
253
253
255
256
256
257
257
258
258
258
259
260
CONTENTS – PART TWO
PAGE
NUMBER
CONTENTS
XXIX
NENE AND PICCANINNIE BIOUNITS -------------------------------MARINE BIOGEOGRAPHY
----------------------------------------1
2
3
Oceanography
Geology and Coastal Geomorphology
Biology
MARINE CONSERVATION VALUES
1
1.1
1.2
2
2.1
2.2
2.3
2.4
2.5
2.6
3
4
----------------------------------------------------------------------------------------------------------------------------------------------------
-----------------------------------------
Significant Biological and Physical Features -------------------------------------------------Biological
-------------------------------------------------Physical
-------------------------------------------------Other Values
-------------------------------------------------Commercial Fisheries
-------------------------------------------------Aquaculture
-------------------------------------------------Recreation and Tourism
-------------------------------------------------Scientific Research and Education
-------------------------------------------------Adjacent Land Use
-------------------------------------------------Significant Cultural and Historical Features
-------------------------------------------------Current Conservation Status of the Nene and Piccaninnie Biounits -----------------------Areas of High Conservation Value in the Nene and Piccaninnie Biounits------------------
BIBLIOGRAPHY
-----------------------------------------
262
262
262
262
262
263
263
263
265
265
265
266
266
266
267
267
268
268
269
CONTENTS – PART TWO
ACKNOWLEDGMENTS
This project has been supported by Environment Australia under the Natural Heritage Trust (Marine Protected
Areas Program) and the former ‘Ocean Rescue 2000 Program’ and represents the culmination of technical and
policy development first conducted by SARDI (formerly the SA Department of Fisheries) in 1991/92. In the
latter stages of this project, the information from the ‘SA Marine Biodiversity Program’ provided essential
information in the definition of areas of high conservation value, and in defining the marine ecological regions
of South Australia.
This work would not have been possible without the support of:
•
•
•
•
•
•
•
•
•
•
•
Environment Australia, which provided funding specifically for this project during 1991/92 and 1995/96;
Deborah Nias, who provided technical summaries of the South East and Kangaroo Island regions and also,
project assistance during 1992;
Participants of the ‘SA Marine Protected Areas Workshop’ held in November 1991, who identified key
areas of high conservation value and potential Marine Protected Area sites;
For digitising and map production (Part 2 of the report): Russell Flavel and Megan Tutty (Geographical
Systems Unit, PIRSA); and Tim Noyce, Belinda Hille (Geographical Analysis and Research Unit,
Department of Transport, Urban Planning and the Arts) and Lyn Scott (SARDI);
Janine Baker (SARDI) and Dr. Hugh Kirkman (CSIRO, Division of Marine Research), who, since 1993
have been major collaborators on the SA Marine Biodiversity Program;
The master (N Chigwidden) and crew (D Kerr, N Wigan, C Foulkes) of the MRV Ngerin, and technical
officers (A Dalgetty, V Boxall, B Davies) who provided invaluable field support for the marine biological
surveys;
Graham Edgar for providing most of the slides for the cover;
CSIRO (Vince Lyne) for providing the satellite image of SA waters;
Jon Bryan for providing slides for the cover;
Ken Hoppen for providing the "Moonlighter" slide for the cover;
The Marine and Coastal Community Network (MCCN) for providing the slide of the Australian Sea Lion.
Finally, I would like to acknowledge the personal support of my colleagues at SARDI (Aquatic Sciences),
particularly Dr Scoresby Shepherd, Annette Doonan and Suyin Deakin.
Dr Karen Edyvane
14 August 1998
The views and opinions expressed in this document are those of the author and do not necessarily reflect the
view or position of SARDI, PIRSA or the South Australian Government. Neither do they reflect those of the
Australian Commonwealth Government or the Minister of the Environment.
Collation of the information presented in this report was undertaken with funding provided by the Australian
National Conservation Agency (now Environment Australia) for the Ocean Rescue 2000 Marine Protected
Areas Program (Project number OR52).
Copyright in this report is vested in the Chief Executive, Primary Industries and Resources South Australia.
The report may be cited as:
Edyvane, K S (1999). Conserving Marine Biodiversity in South Australia - Part 2 - Identification of areas
of high conservation value in South Australia.
INTRODUCTION – PART TWO
INTRODUCTION
1
INTRODUCTION
1.1 The Hierarchical Nature of Biodiversity
In conserving marine biodiversity it is important to
recognise the hierarchical nature of ecosystems,
biodiversity and ecological processes. Biological
diversity can be defined at the ecosystem,
seascape/landscape, species and genetic level.
Marine and coastal systems are extraordinarily
diverse at all these levels. However, due to the
inaccessible nature of the marine environment and
the lack of knowledge of marine biodiversity at the
species level, the measurement of biodiversity in
marine
environments
is
generally
most
approachable and practical at the level of the
seascape or habitat.
In the marine environment, biodiversity occurs at
the scale of large marine ecosystems, such as major
oceanic and pelagic ecosystems, and is defined by
large-scale processes such as oceanography (ie.
currents, upwellings), trophodynamics, coastal
physiography and basin topography. Similarly,
biodiversity also occurs at the smaller scales of
ecosystems (eg. open coasts, gulfs), habitats (eg.
reefs, estuaries, bays) and biological communities
(eg. mangroves, seagrasses, kelp forests, coral
reefs). At these scales, patterns in biodiversity may
be dominated by small-scale physical processes
such as type of substratum, cyclones, storm events,
changes in wave exposure, or biological processes
such as competition and predation. In conserving
the full range of South Australia’s marine
biodiversity needs to be conserved, from the large
marine ecosystems, to the habitat and communitylevel patterns of biodiversity.
What is Biological Diversity ?
The National Strategy for the Conservation of
Australia’s Biological Diversity (1996) defines
biological diversity as the variety of all life forms –
the different plants, animals, microorganisms, the
genes they contain, and the ecosystems of which
they form a part. It is not static, but constantly
changing; it is increased by genetic change and
evolutionary processes and reduced by processes
such as habitat degradation, population decline, and
extinction. The concept emphasises the interrelatedness of the biological world. It covers the
terrestrial, marine and other aquatic environments.
Biological diversity can be considered at three
fundamental levels:
•
−
Genetic diversity:
the variety of genetic information contained in
all of the individual plants, animals and microorganisms that inhabit the earth. Genetic
diversity occurs within and between the
populations of organisms that comprise
individual species as well as among species.
•
−
Species diversity:
the variety of species on earth.
•
−
Ecosystem diversity
the variety of habitats, biotic communities and
ecological processes.
Marine biodiversity conservation in South
Australia also needs to take account of coastal and
oceanographic change over geological time scales,
particularly with respect to the evolution of the
coastal and marine environment and also, land-sea
dynamics (Ray 1991). For temperate southern
Australia, a long period of geological and
continental isolation has resulted in high endemism
in the marine biota (Edyvane 1996), while
continental drift and periods of global warming and
cooling have resulted in significant intrusions of
warm water from the Indo-Pacific, and importantly,
significant sea level changes. In South Australia,
the gulfs region are particularly significant,
containing not only high levels of endemism, but
also, a subtropical element in the marine flora and
fauna.
Ecological processes, resource distributions and
human impacts can also can be understood,
conserved and managed at a range of spatial and
temporal scales. Because of the nested hierarchical
structure of ecosystems, marine management
(including the establishment and management of
Marine Protected Areas) needs to examine and
occur within several temporal and spatial scales
(Ray & McCormick-Ray 1992). The adoption of a
scale-adapted
approach
to
environmental
management and planning requires both, an
understanding of the spatio-temporal hierarchies of
patterns and processes in natural systems, and also,
a recognition of the scales of human impact,
monitoring and management inherent in humanecosystem interactions (see Table 1.1).
i
INTRODUCTION – PART TWO
SCALES OF HUMAN-MARINE ECOSYSTEM INTERACTION
SCALE
ECOSYSTEM
MAJOR PROCESSES
HUMAN IMPACTS
MANAGEME
NT
Global
Biosphere
topography (ocean basins), oceanography,
climate (large-scale)
global warming, sealevel changes
international
1000’s kms
bioprovince
topography
(large-scale),
oceanography
(major currents, temperature), climate
global warming, sealevel changes, ecosystem
stress, reduced biodiversity
international
100’s kms
bioregion
topography, oceanography (upwellings, small
currents), sediment supply
pollution, habitat fragmentation, overfishing,
species loss, ecosystem stress, reduced
biodiversity
national/state
10’s kms
biounit
topography, aspect (exposure), tides, storms,
sediment supply
pollution, habitat loss, overfishing, population
loss, exotic introductions, ecosystem effects
local
1-10’s km
habitat
aspect (exposure), storms, community
dynamics, tides, depositional processes
pollution,
habitat
loss,
overfishing,
aquaculture, dredging, population loss, exotic
introductions, ecosystem effects
local
100’s metres
site
depth, predation, competition, storms
pollution, habitat loss, aquaculture, dredging
population loss, exotic introductions
local
Table 1.1
Scales of human-marine ecosystem interactions (ie patterns, processes, human impacts and management) (from Edyvane 1996).
ii
INTRODUCTION – PART TWO
1.2 Classifying
Marine
Bioregionalisation
Ecosystems
-
1.3 Defining a Marine Bioregional Planning
Framework for South Australia
`Bioregionalisation’, or the definition of
biogeographic regions, is not only an essential step
in marine conservation planning, but also, is
essential in defining a bioregional planning
framework for ecosystem management (Salm &
Clarke 1984, ACIUCN 1986, Sherman et al. 1990,
Ray & McCormick-Ray 1992, Bridgewater &
Ivanovici 1993).
In natural ecosystems, an
understanding of the patterns of biodiversity,
particularly habitat biodiversity, is not only
essential for identifying an ecologically or
biogeographically representative system of
protected areas, but is also essential in defining
scaled ecological units for holistic, integrated
management at the ecosystem level (ie. catchment,
landscape or `seascape management’) (Forman &
Godron 1986, Urban et al. 1987, Kessler et al.
1992, Grumbine 1994, Klijn 1994). Importantly,
the scale and extent to which different human
activities affect either biodiversity and/or
ecological processes, determines both, the scale
and nature of management and monitoring
required, and hence, defines the framework for
integrated, ecosystem management.
As such,
biogeographical regions or `bioregions’ provide the
boundaries and framework for biodiversity or
conservation management and the multiple-use
management of other specific human activities or
uses, such as fisheries, mining, and tourism.
Planning, including identification of priority areas,
is an essential part of a nation’s overall strategy for
conservation and sustainable use of it’s
biodiversity. During the 1990's, South Australia,
with funding under the Natural Heritage Trust (and
the former federal `Ocean Rescue 2000' initiative),
has been developing a bioregional planning
framework to assist with the establishment of a
National Representative System of Marine Protected
Areas (NRSMPA), and also, as a strategic tool for the
integrated management and conservation of it's
coastal and marine environments.
Bioregional
classification of South Australia's coastal and marine
environments is an important initial step in achieving
this goal. To this end, a biophysical classification of
the range of coastal and marine environments in
South Australia can be used to assist in the
identification of ecologically or biogeographically
the
'ecological
representative
areas
and
representativeness' of the existing system of MPAs.
The definition of natural units for management not
only facilitates planning and integrated ecosystem
management, but also assist local managers and the
community in such areas, in understanding the
natural characteristics, features, limitations, and
complexities of their local marine environments.
The process of bioregionalisation classifies similar
regions/habitats together at a range of spatial
scales, within relatively homogenous, but
distinctive, ecological units in terms of their natural
biological and physical characteristics. To this end,
the definition of such regions not only enable a
systematic approach to planning and integrated
management, but also, inventory, monitoring and
audit of the marine environment and its resources.
For marine resources (ie. fisheries, aquaculture,
mining), where spatial distributions and dynamics
are linked to ecological and physical processes and
natural patterns of biodiversity, biogeographic
regions provide an ecological framework for
management which acknowledges the inherent
natural variability and characteristics of marine
ecosystems.
The current strategy for bioregional identification
and classification in South Australia is a
systematic, hierarchically scaled one, with a focus
on the conservation of biodiversity in the context of
ecosystem structure and function. This hierarchical
structure of biodiversity is intrinsically linked to
the level of functional diversity or ecological
processes and attributes. The aim is to identify a set
of natural environmental units defined by
biophysical parameters. In South Australia, the
definition of the bioregional framework has largely
been undertaken by the South Australian Research
and Development Institute, in collaboration with
State and Commonwealth agencies. This has been
achieved largely through the undertaking of a
comprehensive program of marine habitat and
biodiversity mapping (ie. linking spatial
environmental and biological data) to define the
biogeographical regions of South Australia, and
also, identify priority areas for marine
conservation, based on regional patterns of
diversity.
The approach to bioregionalisation in South
Australia uses the nested, hierarchical concept of
ecosystems to develop a five level biophysical
classification at the level of :
1
Pelagic Provinces (100,000s of km2,
gigascale), which provides a broad scale
strategic framework for the integrated
management of pelagic resources; suitable
for integrated pelagic fisheries management
and integrated management of pelagic
resources, global reporting, auditing;
iii
INTRODUCTION – PART TWO
2
Demersal Provinces (10,000s of km2,
macroscale), which provides a broad scale
strategic framework for the integrated
management of demersal resources; suitable
for
integrated
demersal
fisheries
management and integrated management of
demersal resources, global reporting,
auditing;
3
Biophysical Regions or `Bioregions`
(1,000s of km2, mesoscale), which provides
a national strategic framework for marine
planning and ecological sustainable
management of coastal resources; suitable
for national biodiversity and conservation
planning and priority-setting, pelagic
fisheries management, reporting, auditing
(eg. national State of the Environment
Report);
4
Biophysical Units or `Biounits’ (100s of
km2, microscale), which provides a regional
strategic framework for marine planning and
ecological sustainable management of
coastal resources; identifies functional
ecosystem-level management units (eg.
rocky shores, dune barrier systems,
archipelagos, shoals or reef systems, coastal
peninsula, etc.); suitable for integrated
multiple-use management and MPA
declaration, regional biodiversity and
conservation planning and priority-setting,
fisheries management, reporting, auditing,
monitoring, impact assessment;
5
and the level of habitats (1-10s of km2,
picascale) , which provides information to
address tactical site management issues at
the habitat level (eg. bay, estuary, reefs,
seagrass meadows); suitable for nature
reserves, fishing closures, monitoring,
impact assessment.
The marine bioregionalisation at the bioregion and
biounit incorporated and acknowledged the existing
geomorphological classification of the coastal
habitats of South Australia by Short et al. (1986),
which utilised principally physical coastal landform
and descriptors, such as wave environment, geology,
coastal landform and coastal orientation. The results
of this preliminary regionalisation were further
refined and validated through ongoing systematic
field surveys, knowledge of oceanographic processes,
and also, more recently, under the national, Interim
Marine and Coastal Regionalisation of Australia
(IMCRA) project during 1995-1996.
Provinces were defined on the basis of major
oceanographic current systems for the pelagic
regionalisation, and biogeographic patterns in the
marine fish fauna for the demersal classification
(CSIRO 1997, IMCRA 1997). In contrast, marine
bioregions were defined on the basis of a range of
physical descriptors, such as climate, oceanography
(ie. temperature, salinity, tides, wave energy,
upwellings), geology and coastal geomorphology,
estuaries and also, major biogeographic patterns in
the marine biota (particularly the sessile fauna and
flora, such as mangroves, seagrass, macroalgae).
Smaller-scale biounits were defined primarily on
the basis of coastal physiography, topography and
major marine physical habitat or seascape features
(eg. shoal systems, archipelagos, coastal dune
barrier systems, etc.) and habitat distributions.
In the development of a scaled, hierarchical
bioregional planning framework for South
Australia, a total of 1 pelagic province, 1 demersal
province (and 2 biotones), 8 bioregions, and 35
biounits have been identified (see Table 1.2).
In South Australia, a preliminary bioregionalisation
or classification of coastal habitats and ecosystems
adopted an `expert panel' or `delphic' approach,
utilising
existing
`qualitative'
biophysical/
biogeographical information and the best technical
judgements of local experts. This involved the
formation of a specialist, SA Marine Protected Area
Technical Working Group and the hosting of a
technical workshop on the biophysical classification
of South Australian marine and coastal environments
in November 1991.
iv
INTRODUCTION – PART TWO
Table 1.2:
A nested hierarchical bioregional planning framework for South Australia’s coastal and marine ecosystems.
PELAGIC PROVINCE
Gigascale (100,000s km2)
DEMERSAL
PROVINCE/BIOTONES
Macroscale (10,000s km2)
BIOREGION
BIOUNIT
Mesoscale (1,000s km2)
Microscale (100s km2)
Eucla (EUC)
Southern Pelagic Province (SPP)
Great Australian Bight Biotone
(GABB)
Murat (MUR)
Gulfs Province (GulfP)
Eyre (EYR)
Spencer Gulf (SGF)
Northern Spencer Gulf (NSG)
Gulf St Vincent (SVG)
West Bassian Biotone (WbassB)
Coorong (COR)
Otway (OTW)
Nullarbor (NUL)
Wahgunyah (WAH)
Fowlers (FOW)
Nuyts (NUY)
Streaky (STK)
Yanerbie (YAN)
Newland (NEW)
Flinders (FLI)
Sheringa (SHR)
Douglas (DGL)
Whidbey (WHD)
Jussieu (JUS)
Pondalowie (PON)
Gambier (GAM)
Gantheaume (GAN)
Dutton (DUT)
Franklin (FRK)
Tiparra (TIP)
Wardang (WAR)
Yonga (YON)
Winninowie (WIN)
Sturt (STU)
Investigator (INV)
Orontes (ORO)
Clinton (CLN)
Yankalilla (YNK)
Encounter (ENC)
Sprigg (SPR)
Backstairs (BCK)
Nepean (NEP)
Cassini (CAS)
Coorong (COR)
Canunda (CAN)
Nene (NEN)
Piccaninnie (PIC)
v
INTRODUCTION – PART TWO
In several states, including South Australia,
biogeographic or regional ecosystem classifications
have involved utilising analytical multivariate
procedures to classify patterns in nearshore
ecosystem diversity (eg. Ortiz & Burchmore 1992,
Edgar et al. 1995, LCC/DCNR 1995, Stevens 1995,
Edyvane & Baker 1995, 1996). To-date, a total of
58 bioregions have been identified for the
nearshore marine environments of Australia, on the
basis of a wide range of physical and biological
descriptors, such as climate, oceanography (water
temperature, wave energy), tidal range, coastal
geomorphology,
biology
(habitats,
marine
mammals, endemic species) (see Figure 1.1). For
Australia, the challenge remains the critical
integration of the existing terrestrial regionalisation
(ie. Interim Biogeographic Regionalisation of
Australia), with the marine regionalisation (ie.
IMCRA), and also, the integration of inshore and
offshore waters.
1.4 IMCRA - A National Template for Marine
Biodiversity and Ecosystem Management
The approach to bioregionalisation used in South
Australia has formed part of an integrated
coordinated State and Commonwealth effort a to
develop an `Interim Marine and Coastal
Regionalisation of Australia' (IMCRA), to assist in
the development of a representative system of
Marine Protected Areas (Muldoon 1995, IMCRA
1997).
The IMCRA classification is principally a `delphic’
approach to biophysical regionalisation. In South
Australia, this qualitative approach utilised the
expertise of marine and coastal biological and
physical researchers, results from ongoing field
surveys and also, existing descriptive, spatially
referenced biophysical coastal and marine data sets
and maps.
TC
KIM
SEB
MIN
CAR WEI TS
RBN
WWG
BVD
NWS
KS
CAN
EMB
PIO
AW
CAB
SWG
CYP
WEL
GBR
WTC
SBR
LMC
PIN
SB
ZUY
MUR
ABR
SG
PC
EUC
MOR
NSG
MAC
SVG
EYR
CV
COR
WSC
DO
OK
CBS
Interim Marine and Coastal Regionalisation
for Australia (IMCRA) Version 3.0
DAV
GER
ULL
HOW
LN
Figure 1.1:
MCM
SC
WF
FRT
BRU
The mesoscale marine ecosystems of Australia as defined under the Interim Marine
and Coastal Regionalisation of Australia (IMCRA) project (IMCRA 1997).
vi
INTRODUCTION – PART TWO
1.5 `Province’ or Large Marine Ecosystem
Regionalisation
Pelagic Regionalisation
The `Interim Marine and Coastal Regionalisation
of Australia’ (IMCRA 1997) classification defines
one gigascale, pelagic province for South
Australian waters: the Southern Pelagic Province
(SPP). The core area of this province largely
encompasses the Flindersian cool temperate marine
biota.
Southern Pelagic Province (SPP)
•
−
Great Australian Bight Biotone (GABB)
•
−
•
−
Location:
Great Australian Bight from Israelite Bay
(WA) to Point Brown (SA).
•
−
Remarks:
Weak biotone dominated by species from the
South Western Province (SWP) in WA, with a
few elements of the Gulf Province (GulfP) in
SA. A major disjunction exits near the
Recherche Archipelago corresponding to the
western limits of a suite of wide-ranging
species from the Central Eastern Province
(CEP) and Tasmanian Province (TasP), and
the eastern limits of the South Western
Province. The biotone is also traversed by a
large suite of wide-ranging, western, warm
temperate species that extend along the
southern Australian coast to the Gulf
Provinces, Bassian Province (BassP) and the
South Eastern Biotone (SEB), and a suite of
ubiquitous temperate Australian species that
originate in the Central Eastern Province and
Biotone. (CEP and CEB).
•
−
Mesoscale Regions:
Includes Eucla and Murat regions.
Area:
482,000 km2
•
−
Location:
Extending from near Albany (WA) in the
west, along the southern coast, to Lakes
Entrance (Victoria) in the east and enclosing
Bass Strait and the Tasmanian waters.
•
−
Remarks:
Largely comprised of Flindersian cool
temperate species. The endpoint disjunctions
also represent southern limits for warm
temperate species in the Eastern and Western
Pelagic Biotones (WPB and EPB). Intraprovincial disjunctions occur at Esperance and
east of Point Dempster near the western edge
of the Baxter Cliffs. In the east, disjunctions
occur just east of Kangaroo Island and at
Wilsons Promontory
Demersal Regionalisation
The `Interim Marine and Coastal Regionalisation
of Australia’ (IMCRA 1997) classification defines
one macroscale, demersal province for South
Australian waters: the Gulfs Province (GulfP), and
two biotones: the Great Australian Bight Biotone
(GABB) and the West Bassian Biotone (WBassB).
Biotones are the zones of transition between core
provinces. The provinces and biotones are based
on a classification of demersal fish species
diversity and richness.
Area:
200,000 km2
Gulfs Province (GulfP)
•
−
Area:
35,379 km2
•
−
Location:
Comprising the Gulfs of Spencer and St
Vincent and enclosing Kangaroo Island.
Extends out to the shelf break with a western
boundary at Point Brown and an eastern edge
at Cape Jervis.
•
−
Remarks:
A weak but unique province with a small
endemic element and subtropical relict
species. It has a strong disjunction near its
northern boundary and acts as a major biotone
for cool temperate species (TasP and BassP)
and for a large suite of species from the South
Western Province (SWP). The hypersaline
and subtropical temperature conditions in the
Gulfs are unique within temperate Australia
and probably enable this region to act as a
refugia for warmer water species. Once again,
the unique relict nature of the region makes it
worthy of recognition from a conservation
standpoint (IMCRA 1997).
vii
INTRODUCTION – PART TWO
•
−
Mesoscale Regions:
Includes Eyre, Northern Spencer
Spencer Gulf and St Vincent regions.
Gulf,
West Bassian Biotone (WBassB)
•
−
Area:
89,751 km2
•
−
Location:
Extends east from the South Australian Gulfs
Province (GulfP), pentrating past King Island
to a southern limit at the north-western tip of
Tasmania and a northern limit slightly north of
Apollo Bay (Victoria).
•
−
Remarks:
Zone of faunal overlap of elements derived
mainly from the Tasmanian Province (TasP)
and Bassian Province (BassP) to the east, as
well as a small suite of extralimital species
from the Central Eastern Province (CEP).
Also contains elements from the South
Western Province (SWP) and Gulfs Provinces
(GulfP).
•
−
Mesoscale Regions:
Includes Otway and Coorong regions.
1.6 `Bioregion’
Regionalisation
or
Ecosystem-Level
A total of 8 distinct inshore marine biogeographical
regions (or “bioregions”) have been identified for
South Australia (Figure 1.2). The seaward margin
of the mesoscale bioregions is the edge of the
continental shelf, defined as the 200 metre isobath.
These bioregions include from the west: Eucla
(Israelite Bay, Western Australia - Cape Adieu,
South Australia), Murat (Cape Adieu - Point
Labatt), Eyre (Point Labatt - Peake Bay, Cape
Borda - West Cape), Northern Spencer Gulf (Point
Riley - Port Augusta - Shoalwater Point), Spencer
Gulf (Peake Bay - West Cape, Point Riley Shoalwater Point), St Vincent Gulf (Cape Borda West Cape, Cape Jervis - Cape Willoughby),
Coorong (Cape Jaffa - Cape Borda) and OtwayKing (Cape Jaffa - Cape Otway, Victoria - King
Island, Tasmania) (see Table 1.3).
gradients with extensive intertidal, and supratidal
areas (see Table 1.3). The biota is characterised by
extensive areas of coastal saltmarshes, mangroves
(dominated by the Grey Mangrove, Avicennia
marina), and subtidal seagrass meadows. Northern
Spencer Gulf is characterised by a unique tropical
element in the fauna and flora. Together the
bioregions of the gulfs are home to 7,950 km2 of
seagrass or 82% of the total area of seagrass
recorded in South Australia. The most extensive
seagrass meadows (dominated by Posidonia species),
occur in the clear, shallow, sheltered gulf waters of
Northern Spencer Gulf (4,136 km2), with smaller
meadows occurring in Spencer Gulf (5,520 km2)
and Gulf St Vincent (2,440 km2). In contrast, the
oceanic bioregions are dominated by extensive
rocky coasts and sandy shores.
The oceanic bioregions are characterised by
exposed rocky coasts and headlands (comprising
Precambrian metasediment cliffs, Pleistocene dune
rock cliffs), interspersed with Holocene dune
barrier beaches and lagoon deposits in sheltered
areas, microtidal tidal ranges, and shallow to
moderate offshore gradients (see Table 1.3). The
Eucla, Murat and Eyre are characterised by a
predominance of rocky coasts, while the Coorong
and Otway coasts are typically small barrier coasts.
The Eyre, Coorong and Otway Bioregions
experience moderate to high energy wave and swell
conditions (experiencing some of the highest wave
energies in the State), and are dominated by
extensive reefal habitats, sandy bottom substrates
and transgressive dune systems. The Eyre and
Otway regions are also distinguished by the
presence of localised, seasonal, nutrient-rich
coldwater upwellings. In contrast, the Murat
Bioregion comprises a series of extensive, shallow
water embayments, protected by the Nuyts
Archipelago, and dominated by extensive seagrass
meadows and mangroves.
A full description of the bioregions of South
Australia is provided in IMCRA (1997) (see
Appendix 1).
The marine bioregions of South Australia vary
from the oceanic bioregions of Eucla (EUC), Murat
(MUR), Eyre (EYR), Coorong (COR) and Otway
(OTW), to the gulf bioregions of Spencer Gulf
(SGF), Northern Spencer Gulf (NSG) and St
Vincent Gulf (SVG). The gulf bioregions are semiconfined
or
confined
inverse
estuaries,
characterised by tidal plain coasts and landforms,
micro-mesotidal tidal ranges, and shallow offshore
viii
INTRODUCTION – PART TWO
Table 1.3:
A summary of the IMCRA bioregions of South Australia
Bioregion
Total Area of
Bioregion (ha)
SA Area of
Bioregion (ha)
Major Inshore
Habitats
Major Physical
/Biological Descriptors
Eucla (EUC)
11,111,514
189,073
Sand (391 km2, 88.5%)
Reef (51 km2, 11.5)
rocky coast; dominated by the Nullarbor Cliffs and Eucla Basin;
warm water Leeuwin Current; microtidal; warm temperate biota,
moderate biodiversity
Murat (MUR)
3,558,736
133,703
Seagrass (880 km2, 61.3%)
Sand (309 km2, 21.5%)
Reef (246 km2, 17.2%)
rocky crenulate coast, embayments; Nuyts Archipelago,
seamounts; microtidal; warm temperate biota, extensive seagrass
meadows, mangroves
Eyre (EYR)
7,216,500
1,425,723
Sand (1543 km2, 56.2%)
Reef (674 km2, 24.6%)
Seagrass (527 km2, 19.2%)
rocky coast, offshore islands, seamounts; localised upwellings;
microtidal; cool temperate biota, high biodiversity, productivity,
importance for marine mammals, seabirds
Spencer Gulf (SGF)
1,187,451
1,199,299
Seagrass (1377 km2, 41.2%)
Sand (1351 km2, 40.5%)
Reef (611 km2, 18.3%)
tidal plain coast, embayments; shallow offshore gradient; semiconfined, inverse estuary; micro-mesotidal; cool temperate biota,
high endemism, extensive seagrass meadows
444,803
478,824
Seagrass (4136 km2, 58.1%)
Sand (2487km2, 34.9%)
Reef (493 km2, 6.9%)
tidal plain coast; shallow offshore gradient; confined, inverse
estuary; mesotidal; subtropical-tropical element in biota, high
endemism; extensive seagrass meadows, mangroves
St Vincent Gulf (SVG)
1,283,817
1,441,971
Seagrass (2438 km2, 59.6%)
Sand (1057 km2, 25.9%)
Reef (595 km2, 14.5%)
tidal plain coast; shallow offshore gradient; confined, inverse
estuary; micro-mesotidal; cool temperate biota, high endemism,
extensive seagrass meadows, mangroves
Coorong (COR)
3,197,170
178,575
Reef (991 km2, 48.2%)
Sand (812 km2, 39.5%)
Seagrass (255 km2, 12.4%)
large barrier coast; Coorong Lagoon and Murray River;
gradational nearshore-offshore gradient; cool temperate biota,
moderate biodiversity
Otway (OTW)
3,733,126
120,639
Reef (582 km2, 87.4%)
Sand (84 km2, 12.6%)
Seagrass (0.5 km2, 0.1%)
small barrier coast; localised upwellings; cold temperate biota,
high biodiversity, productivity
32,000,000
5,167,807
6,094,800
Northern Spencer Gulf
(NSG)
Total
ix
INTRODUCTION – PART TWO
EUCLA
NORTHERN
SPENCER
GULF
MURAT
EYRE
SPENCER
GULF
GULF
ST VINCENT
COORONG
OTWAY
Figure 1.2: Marine Bioregions of South Australia
1.7 `Biounit’ or Habitat-Level Regionalisation
A total of 35 biounits have been identified along
the inshore coastal waters of South Australia (see
Figure 1.3, Table 1.4). These include a total of 30
coastal biounits and 5 offshore biounits, which
comprise offshore islands and waters without
adjacent mainland coasts (ie. Nuyts, Flinders,
Investigator, Gambier, Sprigg). The biounits were
delineated on the basis of major coastal
physiographic features and the representation and
distribution of major marine habitats.
The seaward boundary of the gulfs biounits was
defined using the 30 m bathymetric contour, on the
basis that major habitat changes are known to occur
in deeper waters, beyond the photic zone.
Similarly, the seaward boundary of the oceanic
biounits was defined using the 50 m depth contour,
on the basis that the photic zone is known to occur
deeper in the clearer oceanic waters of South
Australia.
INTRODUCTION – PART TWO
Table 1.4:
Summary of the marine and coastal biounits for the inshore waters of South Australia.
Bioregion/
Biounit
Inshore/Offshore
Biounit
Total Area
(ha)
SA Waters
(ha)1
Major Feature; Physical/Biological Descriptors; Inshore Habitats
1
EUCLA
Nullarbor
Inshore
842,642
112,959
Nullarbor Cliffs; high energy, limestone cliffs, reefs; sand (11,836 ha, 75.2%) and
reef habitats (3,908 ha, 24.8%)
2
Wahgunyah
Inshore
195,381
76,114
Wahgunyah CR; high energy, extensive dune transgressions; mostly sand (27,971 ha,
94.2%) and some reef habitats (1,722 ha, 5.8%)
1,038,023
189,073
Subtotal
3
MURAT
Fowlers
Inshore
146,486
133,702
Fowlers Bay; high energy, rocky limestone coast; mostly reefs (21,666 ha, 81.9%),
some sand (3,134 ha, 11.9%) and seagrass habitats (1,639 ha, 6.2%)
4
Nuyts
Offshore
283,165
250,448
Nuyts Archipelago; offshore islands; mostly reefs (2,483 ha, 91.6%), some seagrass
(144 ha, 5.3%) and sand habitats (84 ha, 3.1%)
5
Streaky
Inshore
190,949
190,950
Streaky Bay; sheltered embayments, rocky headlands; mangroves, large areas of
seagrass (86,163 ha, 77.6%), some sand (22,466 ha, 20.2%), and reef habitats (2,343
ha, 2.1%)
620,600
575,101
Subtotal
1
SA waters refers to territorial sea, land and inland waters.
xi
INTRODUCTION – PART TWO
Table 1.4:
Summary of the marine and coastal biounits for the inshore waters of South Australia (cont….)
Bioregion/
Biounit
Inshore/Offshore
Biounit
Total Area
(ha)
6
EYRE
Yanerbie
Inshore
82,854
80,569
Yanerbie Sandpatch; high energy, rocky limestone coastline; sand (9,573 ha, 43.6%),
seagrass (6,602 ha, 30.0%) and reef habitats (5,802 ha, 26.4%)
7
Newland
Inshore
45,238
39,714
Newland Barrier; high energy, extensive dune barrier system; mostly sand (4,318 ha,
57.2%) and reef (3,231 ha, 42.8%) habitats
8
Flinders
Offshore
125,957
64,660
Flinders Isles; high energy, offshore islands, seamounts; mostly reef habitats (4,194
ha)
9
Sheringa
Inshore
51,156
42,156
Sheringa Lagoon; high energy, large barrier dune systems; mostly reef habitats (4,605
ha, 94.1%), some sand (224 ha, 4.6%) and seagrass habitats (65 ha, 1.3%)
10 Douglas
Inshore
67,645
66,729
Port Douglas; moderate to low energy, large sheltered embayments, rocky headlands;
sand (18,619 ha, 50.1%), seagrass (8,567 ha, 23.1%), and reef habitats (9,965 ha,
26.8%)
11 Whidbey
Inshore
132,689
107,839
Whidbey Isles; high energy, rocky coast, offshore islands, seamounts, localised
upwellings; most sand (38, 489 ha, 88.1%) and some reef habitat (5,221 ha, 11.9%)
12 Jussieu
Inshore
240,439
240,439
Jussieu Peninsula; large sheltered embayments, rocky headlands, offshore islands;
sand (65,921 ha, 42.9%), seagrass (56,956 ha, 37.1%) and reef habitats (30,649 ha,
20.0%)
13 Pondalowie
Inshore
22,130
22,131
Pondalowie Bay; high energy, rocky coastline, upwellings; sand (15,077 ha, 83.9%),
reef (2,862 ha, 15.9%) and some seagrass habitats (25 ha, 0.1%)
14 Gantheume
Inshore
167,363
111,066
Cape Gantheaume; high energy, rocky coast; mostly reef (31,857 ha, 60.5%), sand
(19,521 ha, 37.1%) and some seagrass habitat (1,263 ha, 2.4%)
935,471
775,302
Subtotal
1
SA Waters
(ha)1
Major Feature; Physical/Biological Descriptors; Inshore Habitats
SA waters refers to territorial sea, land and inland waters.
xii
INTRODUCTION – PART TWO
Table 1.4:
Summary of the marine and coastal biounits for the inshore waters of South Australia (cont….)
Bioregion/
Biounit
Inshore/Offshore
Biounit
Total Area
(ha)
SPENCER
15 Dutton
Inshore
255,443
255,443
Dutton Bay; sheltered rocky coast; mostly seagrass (25,706 ha, 98.5%), some reef
(197 ha, 0.8%) and sand habitats (190 ha, 0.7%)
16 Franklin
Inshore
198,588
198,588
Franklin Harbour; large sheltered embayment; mangroves, sand (87,258 ha, 61.4%),
reef (39,361 ha, 27.7%) and seagrass habitats (15,447 ha, 10.9%)
17 Tiparra
Inshore
243,228
243,228
Tiparra Reef; moderately-high energy, extensive shallow seagrass-reef shoal system;
seagrass (83,912 ha, 81.3%), reef (4,491 ha, 4.4%) and sand habitats (14,782 ha,
14.3%)
18 Wardang
Inshore
285,583
285,583
Wardang Island; moderate energy, large embayment, rocky headlands; sand (65,722
ha, 44.7%), reef (54, 739 ha, 37.3%), seagrass habitats (26, 458 ha, 18.0%)
19 Gambier
Offshore
536,544
536,544
Deeper water habitats of the Spencer Gulf; Gambier Isles; sand (15,160 ha, 68.4%),
seagrass (5,123 ha, 23.1%) and some reef habitat (1,865 ha, 8.4%)
1,519,388
1,519,388
Subtotal
SA Waters
(ha)1
Major Feature; Physical/Biological Descriptors; Inshore Habitats
NORTHERN SPENCER
GULF
20 Yonga
Inshore
55,267
55,267
Yonga Shoal; sheltered gulf waters, shoals; large areas of seagrass (248,596 ha,
59.1%) and sand (161,715 ha, 38.5%), some reef habitat (10,054 ha, 2.4%)
21 Winninowie
Inshore
423,557
423,557
Winninowie CP; very sheltered gulf waters; mostly sand (37,727 ha, 69.6%) and
seagrass habitats (16,484 ha, 30.4%)
478,824
478,824
Subtotal
1
SA waters refers to territorial sea, land and inland waters.
xiii
INTRODUCTION – PART TWO
Table 1.4:
Summary of the marine and coastal biounits for the inshore waters of South Australia (cont….)
Inshore/Offshore
Biounit
Total Area
(ha)
GULF ST VINCENT
22 Sturt
Inshore
183,058
183,058
Sturt Bay; moderate-high energy, large bays, rocky headlands; seagrass (25,611 ha,
75.0%), reefs (5,088 ha, 14.9%) and sand habitats (3,465 ha, 10.1%)
23 Investigator
Inshore
280,063
280,063
Investigator Strait; moderate-high deepwater habitats; sand (490 ha)
24 Orontes
Inshore
183,762
183,762
Orontes Bank; extensive shallow seagrass-reef shoal system; seagrass (51,713 ha,
56.5%), reef (33,745 ha, 36.9%) and sand habitats (6,081 ha, 6.6%)
25 Clinton
Inshore
249,136
249,136
Clinton CR; sheltered gulf waters; large areas of mangroves, seagrasses (132, 576 ha,
84.4%), sand (21,173 ha, 13.5%) and some reef habitat (3,280 ha, 2.1%)
26 Yankalilla
Inshore
51,562
51,562
Yankalilla Bay; moderate energy, bays, rocky headlands; sand (15,845 ha, 62.2%)
and seagrass (7,645 ha, 30.0%), some reefs (1,966 ha, 7.7%)
27 Encounter
Inshore
39,389
39,389
Encounter Bay; high energy, rocky coast, bays; mostly reef (5,452 ha, 57.8%), sand
(3,482 ha, 36.9%) and some seagrass habitat (505 ha, 5.4%)
28 Sprigg
Offshore
160,548
160,548
29 Backstairs
Offshore
35,911
35,322
Backstairs Passage; strong tidal currents, deepwater habitats; seagrass (668 km,
52.1%), reef (527 km, 41.1%), and some sand habitats (87 km, 6.8%)
30 Nepean
Inshore
102,304
102,232
Nepean Bay; sheltered embayments; mostly seagrass (23,229 ha, 49.6%), sand
(21,523 ha, 45.9%), and some reef habitat (2,124 ha, 4.5%)
31 Cassini
Inshore
45,760
45,760
Cape Cassini; moderate energy, rocky coast; mostly sand (12,943 ha, 81.6), reef
(2,263 ha, 14.3%) and some seagrass habitat (662 ha, 4.2%)
1,331,491
1,330,950
Bioregion/
Biounit
Subtotal
1
SA Waters
(ha)1
Major Feature; Physical/Biological Descriptors; Inshore Habitats
Deeper water habitats of Gulf St Vincent
SA waters refers to territorial sea, land and inland waters.
xiv
INTRODUCTION – PART TWO
Table 1.4:
Summary of the marine and coastal biounits for the inshore waters of South Australia (cont….)
Bioregion/
Biounit
COORONG
32 Coorong
Inshore/Offshore
Biounit
Inshore
Subtotal
Total Area
(ha)
SA Waters
(ha)1
1,290,715
178,575
1,290,715
178,575
Major Feature; Physical/Biological Descriptors; Inshore Habitats
Coorong Lagoon; high energy, extensive lagoon system, dune barrier; mostly sand
(75,497 ha, 44.2%), reef (70,376 ha, 41.2%) and some seagrass habitat (25,062 ha,
14.7%)
OTWAY
33 Canunda
Inshore
233,897
84,833
Canunda NP; high energy, rocky coast, dune barriers, offshore reefs; mostly reef
(50,552 ha, 90.5%), some sand (5,333 ha, 9.5%) and sparse seagrass (2 ha, <0.1)
34 Nene
Inshore
32,543
19,061
Nene Valley CP; high energy, rocky coast, offshore reefs; mostly reef habitat (9,981
ha, 97.7%), and some sand habitat (234 ha, 2.3%)
35 Piccaninnie
Inshore
44,923
16,746
Piccaninnie Ponds CP; rocky coast, offshore reefs; mostly sand habitats (2,798 ha,
79.6%), some reefs (675 ha, 19.2%) and sparse seagrass (44 ha, 1.3%)
311,363
120,639
Subtotal
1
SA waters refers to territorial sea, land and inland waters.
xv
INTRODUCTION – PART TWO
Some of the marine biounits identified for South
Australia encompass solely state jurisdictional
waters (eg. biounits within the gulfs). Other
biounits encompass both SA and Commonwealth
territorial seas. As expected, the representation and
range of marine ecosystems varies considerably
between the biounits (see Table 1.4), from the reefseagrass shoal systems of Orontes and Tiparra, to
the offshore islands and seamounts of Whidbey and
Flinders, to the large seagrass-dominated
embayments of Jussieu and Streaky, to the
mangrove-seagrass inverse estuaries of Clinton,
Winninowie, and Yonga. The Yonga biounit alone
represents over 25% of the total seagrass recorded
in South Australia. Other significant ecosystems
include the strong tidal current ecosystem of
Backstairs, the rocky cliff habitats of Nullarbor and
the extensive nearshore reefs systems of Canunda
and Nene.
WAH
NUL
STK
FOW
NUY
WIN
YAN
NEW
YON
FRK
SHR
FLI
DUT
DGL
TIP
JUS
CLN
WAR
GAM
ORO
WHD
STU
SPR
YNK
INV
NEP
GAN
ENC
BCK
COR
CAN
NEN
PIC
Figure 1.3
Marine Bioregions and Biounits of South Australia
1.8 Criteria
for
Identifying
Conservation Significance
Areas
of
The present approach to identifying areas of high
marine conservation value in South Australia,
utilises a analytic approach, which applies formal
criteria, based on a range of ecological, social and
economic criteria to identify areas of high
conservation value (for establishment as potential
Marine Protected Areas). Application of these
criteria acknowledges:
−
previous recommendations of the SA Marine
Protected Areas Technical Working Group
(see Edyvane and Baker 1995)
−
areas of recognised State significance (eg.
National
Parks,
Conservation
Parks,
−
−
Conservation Reserves, sites listed on the SA
Heritage List, historic shipwrecks, geological
monuments)
areas of recognised national significance (eg.
Wetlands of National Importance, sites listed
on the Register of the National Estate)
areas of recognised international significance
(eg. RAMSAR listed sites)
The following is a list of formal criteria endorsed
by IUCN (Kelleher & Kenchington 1991) and
nationally (Environment Australia 1998), which
can used in the identification of areas of
conservation significance for potential selection as
part of a nationally representative system of
MPA’s:
xvi
INTRODUCTION – PART TWO
•
−
Naturalness:
this is the extent to which the area has been
protected from, or has not been subject to
human-induced change (eg. wilderness areas).
•
−
Biogeographic Importance:
an area which possesses either rare
biogeographic qualities or is representative of
a biogeographic "type" or types; contains
unique or unusual geological features.
•
−
Ecological Importance:
an area which contributes to maintenance of
essential ecological processes or life-support
systems eg. source for larvae for downstream
areas; integrity - the degree to which the area
either by itself or in association with other
protected areas, encompasses a completer
ecosystem; contains a variety of habitats;
contains habitat for rare or endangered
species; contains nursery or juvenile areas (eg.
seagrass, mangroves); contains feeding,
breeding or rest areas; contains rare or unique
habitat for species; preserves genetic diversity,
ie. is diverse or abundant in species terms.
•
−
Economic Importance:
an area of existing or potential contribution to
economic value by virtue of its protection eg.
protection of an area for recreation,
subsistence, use by traditional inhabitants,
appreciation by tourists and others or as a
refuge nursery area or source of supply for
economically important species (eg. fish
nursery/breeding/feeding areas).
•
−
Social Importance:
an area of existing or potential value to the
local, national or international communities
because of its heritage, historical, cultural,
traditional
aesthetic,
educational
or
recreational qualities.
•
−
Scientific Importance
an area of value for research and monitoring
(eg. research sites in which to demonstrate
ecological processes or monitor global
change)
•
−
International or National Significance:
an area which is or has the potential to be
listed on the World or a national Heritage List
or declared as a Biosphere Reserve or included
on a list of areas of international or national
importance or is the subject of an international
or national conservation agreement.
•
−
Practicality/feasibility:
an area with a degree of insulation from
external destructive influences; social and
political acceptability, degree of community
support; accessibility for education, tourism,
recreation; compatibility with existing uses,
particularly by locals; ease of management,
compatibility with existing management
regimes (eg. adjacent to terrestrial parks).
Areas adjacent to terrestrial parks benefit from
their proximity to terrestrial parks because
there are likely to be less environmentally
damaging threats to the marine environment
from the controlled and protected terrestrial
sources within the park. As such, terrestrial
parks act as buffer zones to MPAs.
By examining a range of these IUCN attributes it is
possible to identify areas of high conservation
values in South Australia, based on a range of
natural, social, economic and cultural criteria.
Areas in South Australia of where these IUCN
attributes apply are based on application of the
formal criteria, and are outlined later in this report
for each coastal region and recognised biounit.
xvii
INTRODUCTION – PART TWO
Appendix 1: The IMCRA bioregions of South Australia (from IMCRA 1997)
Region Code & Number
Data Attribute
Description
COR
SA / 43
COORONG
Climate:
Cool temperate, meso-thermal climate with cool, wet winters and warm, dry summers.
Oceanography:
Waters are transitional warm to cold temperate, with mean sea surface temperatures varying from 14oC in winter to
19oC in summer. Offshore gradient decreases from steep to flat resulting in a gradational coastline, from high
deepwater wave energies at Cape Jaffa to low energies near the Murray Mouth. Tidal range, microtidal, ~ 0.8 to 1.2
metre range.
Coastal Geology and
Geomorphology
Large barrier coast dominated by a gradational nearshore-offshore gradient and bio-clastic carbonate sediments. Coast
comprising headlands and cliffs of Precambrian crystalline rock and metasediments and also, Pleistocene dune rock
cliffs, headlands, shore platforms and reefs, interspersed with Holocene pocket beaches. Southern coast dominated by
a large beach-dune barrier lagoon complex comprising the extensive Coorong lagoon and Holocene beach ridge plains
of Lacepede Bay. Offshore gradient traversed by the extensive Murray Canyons which extend offshore from the
Murray River.
Biota:
Marine flora and fauna typical of transitional warm to cold temperate waters (ie. Flindersian Province). Intertidal and
sublittoral fringe dominated by the brown alga, Cystophora intermedia. On rocky limestone shores, subtidal macroalgal communities are dominated by red algae assemblages (particularly Osmundaria and species of Plocamium),
species of Caulerpa (particularly C.flexilis) and Cystophora (such as C.subfarcinata, C.monoliformis and
C.platylobium) and Ecklonia radiata. Granite boulder coasts are dominated by Scytothalia dorycarpa, Acrocarpia
paniculata, Carpoglossum confluens, and Ecklonia radiata on exposed coasts and species of Cystophora in areas of
moderate wave energies. Extensive seagrass meadows occur at Kingston (Lacepede Bay). Seagrass meadows
dominated by Posidonia australis in shallow areas, and P.angustifolia. Lacepede Bay is the easterly limit of
P.sinuosa. Plant species diversity is moderate to low. Coorong Lagoon supports one of the largest concentrations of
waterbirds and migratory waders in Australia. Coastal wetlands of national importance in the region include the
Coorong Lagoon (including Lake Alexandrina and Lake Albert), and the Tookayerta and Finniss River.
Estuaries:
Region dominated by the Murray River and extensive estuarine and ephemeral salt lakes of the Coorong Lagoon.
xviii
INTRODUCTION – PART TWO
Appendix 1: The IMCRA bioregions of South Australia (from IMCRA 1997) (cont….)
Region Code & Number
Data Attribute
Description
EUC
WA & SA / 37
EUCLA
(SA)
Climate:
Semi-arid or `Mediterranean' climate, with hot, dry summers and cool, moist winters.
Oceanography:
Waters are transitional warm to cold temperate, with mean sea surface temperatures varying from 14oC in winter to
19oC in summer (increasing to 22oC in summer under the seasonal influence of the warm water Leeuwin Current).
Open moderate to high wave energy, west-facing coastline. High wave swell environment, 2-4m. Tidal range,
microtidal ~ 0.8 to 1.2 metre range.
Coastal Geology &
Geomorphology:
Rocky cliff coastline, with a shallow offshore gradient, dominated by bio-clastic carbonate sediments. Coastal geology
characterised by the sedimentary Eucla Basin and dominated by the Nullarbor Tertiary limestone cliffs, Pleistocene
dune rock headlands and reefs, interspersed with Holocene beaches and dune barriers. Narrow intertidal rock
platforms are present at the base of the cliffs in some places.
Biota:
Marine flora and fauna typical of transitional warm to cold temperate waters (ie. Flindersian Province). Intertidal and
sublittoral fringe dominated by the brown alga, Cystophora intermedia. On the high energy limestone reefs, subtidal
macro-algal communities are dominated by Scytothalia dorycarpa and Ecklonia radiata, with species of Cystophora
(such as C.platylobium) as subdominants. Few seagrass communities along this high energy coast. Plant species
diversity is moderate to low. Significant breeding and calving area of the Southern Right Whale (Eubalaena australis)
and large number of breeding colonies of the Australian Sea Lion (Neophoca cinerea). Distinct tropical element in the
fauna and flora of the region (ie. plankton, fish, echinoderms, hydroids), due to the warm water Leeuwin Current.
Estuaries:
No true rivers or estuaries in this region.
xix
INTRODUCTION – PART TWO
Appendix 1: The IMCRA bioregions of South Australia (from IMCRA 1997) (cont….)
Region Code & Number
Data Attribute
Description
EYR
SA / 39
EYRE
Climate:
Semi-arid or `Mediterranean' climate, with hot, dry summers and cool, moist winters.
Oceanography:
Waters are transitional warm to cold temperate, with mean sea surface temperatures varying from 14oC in winter to
19oC in summer (decreasing to 11-12oC under the influence of localised, cold nutrient-rich coastal upwellings).
Moderate to high deepwater wave energy coastline. Tidal range, microtidal ~ 0.8 to 1.2 metre range.
Coastal Geology &
Geomorphology:
Rocky coast with a shallow to moderate offshore gradient, dominated by bio-clastic carbonate sediments, comprising
numerous headlands and sheltered, extensive shallow embayments, dominated by seagrasses. Coastal geology on
exposed rocky coasts comprises Precambrian metasediment cliffs and also, Pleistocene dune rock cliffs, headlands and
shore platforms, interspersed with Holocene dune barriers beaches and lagoon deposits in sheltered areas. Cainozoic
colluvial and fluvial sediments. Numerous offshore islands and seamounts.
Biota:
Marine flora and fauna typical of transitional warm to cold temperate waters (ie. Flindersian Province). Intertidal and
sublittoral fringe on rocky shores dominated by the brown alga, Cystophora intermedia. On rocky limestone shores,
subtidal macro-algal communities are dominated by red algae assemblages (particularly Osmundaria and species of
Plocamium), species of Caulerpa (ie. C.flexilis) and Cystophora (such as C.subfarcinata, C.monoliformis and
C.platylobium) and Ecklonia radiata. In sheltered areas, subtidal seagrass communities dominated by Posidonia
australis in shallow waters, and P.sinuosa, P. angustifolia, Amphibolus antarctica and A. griffithsii in deeper waters.
Plant species diversity is high, particularly among the red algae. Marine fish fauna characterised by the presence of
the SA endemic, Crested Threefin (Norfolkia cristata). Significant breeding colonies of the Australian Sea Lion
(Neophoca cinerea) and New Zealand Fur Seal (Arctocephalos forsteri), particularly on the offshore islands. Coastal
wetlands of national importance in the region include, Streaky Bay (Acraman Creek), Point Labatt, Baird Bay, Lake
Newland, Lake Hamilton, Coffin Bay, Tod River, Tumby Bay, on the Eyre Peninsula and D’Estres Bay, Rocky River,
Breakneck River, North West River, South West River on Kangaroo Island.
Estuaries:
No true rivers, but several intermittent streams (eg. Tod River, First Creek on Eyre Peninsula, and
Stun’sail Bloom, Breckneck, Rocky, Wilson, Eleanor, Harriet, South West Rivers on southern
Kangaroo Island) and coastal salt lakes (eg. Lake Newland, Lake Hamilton).
xx
INTRODUCTION – PART TWO
Appendix 1: The IMCRA bioregions of South Australia (from IMCRA 1997) (cont….)
Region Code & Number
Data Attribute
Description
MUR
SA / 38
MURAT
Climate:
Semi-arid or `Mediterranean' climate, with hot, dry summers and cool, moist winters.
Oceanography:
Waters are transitional warm to cold temperate, with mean sea surface temperatures varying from 14oC in winter to
19oC in summer (increasing to 22oC in summer under the seasonal influence of the warm water Leeuwin Current).
Moderate to low wave energy coastline. Tidal range, microtidal ~ 0.8 to 1.2 metre range.
Coastal Geology &
Geomorphology:
Rocky crenulate coastline, with a shallow offshore gradient, dominated by bio-clastic sediments, and comprising
numerous shallow sheltered embayments, dominated by seagrasses. Coastal geology comprising headlands of
Precambrian crystalline rock (usually with a dune rock capping), and Pleistocene dune rock cliffs, reefs and headlands,
interspersed with Holocene beaches, dunes and estuarine deposits including intertidal and supratidal flats. Numerous
offshore islands and seamounts.
Biology:
Marine flora and fauna typically warm temperate (ie. Flindersian). Extensive seagrass communities in embayments
and lee of islands. On sandy shores, in sheltered areas, intertidal flats are dominated by the grey mangrove, Avicennia
marina, the brown alga, Hormosira banksii, and the seagrasses, Heterozostera muelleri and Zostera tasmanica.
Subtidal seagrass communities dominated by Posidonia australis in shallow waters, and P.sinuosa, P. angustifolia,
Amphibolus antarctica and A. griffithsii in deeper waters. On rocky shores, exposed limestone coasts are dominated by
Ecklonia radiata and Scytothalia dorycarpa.
In calmer areas, macro-algal communities are dominated by Sargassum and Osmundaria on moderate coasts and
Scaberia agardhii in low wave energy conditions. Granite boulder reefs are dominated by Scytothalia dorycarpa and
species of Cystophora (such as C.monoliformis). Plant species diversity is moderate to low. Distinct tropical element
in the fauna and flora of the region (ie. plankton, fish, echinoderms, hydroids), due to the Leeuwin Current. Coastal
wetlands of national importance in the region include Davenport Creek (Tourville Bay).
Estuaries:
No true rivers, but a few intermittent streams and tidal mangrove creeks (eg. Davenport Creek).
xxi
INTRODUCTION – PART TWO
Appendix 1: The IMCRA bioregions of South Australia (from IMCRA 1997) (cont….)
Region Code & Number
Data Attribute
Description
NSG
SA / 40
NORTH SPENCER GULF
Climate:
Semi-arid or `Mediterranean' climate, with hot, dry summers and cool, moist winters.
Oceanography:
Confined inverse estuary, with minimal freshwater water input and higher salinities and temperatures in the upper
reaches of the Gulf. Waters are transitional warm to cold temperate, with mean sea surface temperatures varying from
11-24°C at Point Lowly and 13-29°C at Port Augusta. Mean salinity increases from 42.0-44.8% at Point Lowly, to
43.2-48.6% at Port Augusta. Low wave energy coastline. Tidal range, microtidal to mesotidal 1.8 to 3.6 metre range.
Tides are typified by a regular period of minimal tidal movement or `dodge tide'.
Coastal Geology &
Geomorphology:
Tidal plain coast comprised of shallow offshore gradients, extensive intertidal and supratidal areas dominated by
samphires, mangroves, and seagrasses. Coastal geology comprises Precambrian metasediment shore platforms,
Holocene sandflats, beach ridges, recurved spits, and extensive intertidal and supratidal flats.
Biota:
Marine flora and fauna typical of transitional warm to cold temperate waters (ie. Flindersian Province), but with a
distinct subtropical element, characterised by the presence of tropical species such as the brown alga, Sargassum
decurrens and Hormophysa triquetra. In sheltered areas, intertidal flats are dominated by extensive areas of the grey
mangrove, Avicennia marina, together with the brown alga, Hormosira banksii, and the seagrasses, Heterozostera
muelleri and Zostera tasmanica. Subtidal areas characterised by extensive sandy substrates and seagrass meadows,
dominated by Posidonia australis in shallow areas, P.sinuosa, P.angustifolia and Amphibolus antarctica in deeper
waters, and small shore fringing macro-algal communities. Limited rocky areas by macro-algal communities
dominated by Scaberia agardhii, Lobophora, Cystophora botryoides and C.expansa and Caulocystis. Plant species
diversity very low. Sparse to no plant cover in deeper waters (>17 metres), animal dominated. Coastal wetlands of
national importance in the region include the upper Spencer Gulf mangroves from Port Augusta, south to Whyalla and
Jarrold’s Point, Fisherman’s Bay and Port Broughton.
Estuaries:
No true rivers, but many intermittent streams and tidal mangrove creeks (eg. Chinaman Creek, First-Seventh Creeks,
Port Davis Creek, Fisherman Creek).
xxii
INTRODUCTION – PART TWO
Appendix 1: The IMCRA bioregions of South Australia (from IMCRA 1997) (cont….)
Region Code & Number
Data Attribute
Description
OTW
SA, VIC & TAS / 44
Climate:
Oceanography:
OTWAY
Cool temperate, meso-thermal climate with cool, wet winters and warm, dry summers.
Coastline typically high energy, with wave energy dependent on the orientation to prevailing swell direction and cross
shelf width. The western region is typified by a high deepwater wave energy, attenuated by a steep offshore-nearshore
gradient and offshore reefs which provide for moderate to low energy conditions. Waters are cold temperate and
typified by localised, regular, seasonal, cold, nutrient-rich coastal upwellings in the west of the region. Mean sea
surface temperatures vary from 14oC in winter to 18o C in summer (decreasing to 11-12o C under the influence of the
upwellings). The far eastern region (ie. King Island area) is influenced during winter months by warm waters, making
this region warmer than other Tasmanian waters at that time. Here also, summer water temperatures are cooler than
elsewhere in the Bassian Province.
Tidal range is microtidal (ie. ~ 0.8 to 1.2 metres range), through much of the area, however tidal ranges and velocities
vary rapidly in the that part of the region forming the western entrance to Bass Strait.
In the western region, two large unconfined aquifers (in the Gambier Limestone and Dilwyn Formation) discharge
freshwater at the coast via beach springs and spring lakes.
Narrow, dominantly south west facing, continental shelf, including the western entrance to Bass Strait. Small barrier
coast dominated by a steeply sloping offshore gradient, dominated by bio-clastic carbonate sediments, and few coastal
embayments. Coastal geology comprises headlands of Pliocene - Pleistocene volcanic outcrops, and also Pleistocene
dune rock cliffs, shore platforms and offshore reefs (which provide coastal protection), Tertiary sediments and around
King Island, Palaeozoic granite and associated sediments. Sandy beaches common in the western region (and around
King Island), and also, within coastal embayments (ie. Rivoli Bay, Guichen Bay) which are characterised by Holocene
beach ridge plains, beaches and dunes. Cliffed shorelines common elsewhere.
Marine flora and fauna typically cold temperate (ie. Maugean element of the Flindersian Province). Intertidal and
sublittoral fringe on wave-exposed coasts dominated by the bull kelp, Durvillea potatorum. Rocky subtidal macroalgal communities are dominated by Macrocystus angustifolia, Phyllospora comosa and other large brown fucoid
algae. For many macro-algal communities, this region forms the westward limit of a number of key species.
Extensive areas of seagrass occur in the limited sheltered embayments, with smaller areas in the lee of reefs. Subtidal
seagrass meadows dominated by Posidonia australis in shallow areas, P.sinuosa, P.angustifolia and Amphibolus
antarctica in deeper waters. Rivoli Bay is the easterly limit of P.coriacea and P.denhartogii. Port MacDonnell is the
easterly limit of P.angustifolia. Plant species diversity is very high, particularly among the red algae.
Fish and plant species richness both high compared to other South Australian, Victorian and Tasmanian regions. This
is the only recorded area within Tasmanian waters where several species more typically associated with South
Australia occur (for eg. the queen morwong Nemadactylus valenciennesi). Coastal wetlands of national importance in
the region include Butchers and Salt Lakes, Ewens Ponds, Piccaninnie Ponds and the coastal lakes of Lake Robe,
Eliza, George, and St Clair.
No true rivers in the western region, but a few groundwater fed creeks (eg. Eight Mile Creek, Ellards Creek), and
coastal salt lakes intermittently connected to the sea (eg. Lake George). Six moderate-sized barrier estuaries on King
Island and numerous coastal lagoons. See also VE - Victorian estuaries.
Coastal Geology
& Geomorphology:
Biology:
Estuaries:
xxiii
INTRODUCTION – PART TWO
Appendix 1: The IMCRA bioregions of South Australia (from IMCRA 1997) (cont….)
Region Code & Number
Data Attribute
Description
SVG
SA / 42
ST VINCENT GULF
Climate:
Semi-arid or `Mediterranean' climate, with hot, dry summers and cool, moist winters.
Oceanography:
Confined inverse estuary, with higher salinities and temperatures in the upper reaches of the Gulf. Waters are
transitional warm to cold temperate, with mean sea surface temperatures varying from 12°C in winter to 25.9°C in
summer and mean salinities varying from 35.5-42.0%. Low to moderate wave energy coastline. Tidal range,
microtidal to mesotidal ~ 1.2 to 3.3 metre range in the upper Gulf areas. Tides are typified by a regular period of
minimal tidal movement or `dodge tide'.
Coastal Geology &
Geomorphology:
Tidal plain coast with a shallow offshore gradient, extensive intertidal and supratidal areas, and few embayments.
Coastal geology comprises headlands of Precambrian metasediment and Tertiary cliffs and Holocene beaches,
sandflats, dunes, beach ridges, and estuarine deposits.
Biota:
Marine flora and fauna typically cool temperate (ie. Flindersian Province). In sheltered areas, extensive intertidal flats
are dominated by the grey mangrove, Avicennia marina, the brown alga, Hormosira banksii, and the seagrasses,
Heterozostera muelleri and Zostera tasmanica. Extensive subtidal seagrass communities occur down to 17 metres
water depth (becoming sparsely vegetated at greater depths). Subtidal areas characterised by extensive seagrass
meadows, dominated by Posidonia australis in shallow areas (and northern gulf), P.sinuosa, P.angustifolia and
Amphibolus antarctica in deeper waters (and mid-gulf and sheltered parts of the lower gulf), and small shore fringing
macro-algal communities. Seagrasses in the P.ostenfedii group form small communities along exposed parts of the
lower gulf. Isolated reefs and rocky shore algal communities are dominated by Scaberia agardhii and species of
Sargassum in sheltered areas, and Ecklonia radiata, Seirococcus axillaris and species of Cystophora in moderately
exposed areas. Plant species diversity low. Distinct SA endemic and subtropical element in the fish fauna (ie.
Vanacampus vercoi, Acentronura australe, Campichthys tryoni). Coastal wetlands of national importance in the
region include Clinton, Barker Inlet estuary, Wills Creek, Davenport Creek, Port Gawler, and on Kangaroo Island,
American River and Cygnet River.
Estuaries:
A few true rivers (eg. Onkaparinga, Port Adelaide, Wakefield Gawler Rivers), and several intermittent streams and
tidal mangrove creeks (eg. American River, Clinton, Wills Creek, Port Gawler).
xxiv
EYRE REGION
MARINE BIOGEOGRAPHY AND CONSERVATION VALUES
OF THE EYRE COAST
MARINE BIOGEOGRAPHY
1
2
3
4
5
The Eyre Coast
Oceanography
Climate
Coastal Geomorphology and Landforms
Biology
MARINE CONSERVATION VALUES
1
2
3
Significant Biological Physical Features
Significant Cultural and Historical Features
Current Conservation Status of the Eyre Coast
BIOUNITS:
1
2
3
4
5
6
7
8
9
Nullarbor
Wahgunyah
Fowlers
Streaky and Nuyts
Yanerbie
Newland
Sheringa and Flinders
Douglas
Whidbey
Page 1
EYRE REGION
I
MARINE BIOGEOGRAPHY AND CONSERVATION VALUES OF
THE EYRE COAST
MARINE BIOGEOGRAPHY
−
Western Barriers - this subprovince extends
from the Head of Bight to Cape Adieu and
represents a coastal distance of 122 km.
1
−
Crenulate Bay and Barriers - this subprovince
extends from Cape Adieu to Talia Caves on the
western Eyre Peninsula, and represents a coastal
distance of 576 km.
−
Newland Barriers - this subprovince extends
from Talia Caves to Cape Finnis on the western
Eyre Peninsula, and represents a coastal
distance of 38 km.
−
Elliston Cliff - this subprovince extends from
Cape Finnis to Drummond Point on the western
Eyre Peninsula, and represents a coastal
distance of approximately 81 km.
−
South-western Eyre Peninsula - this
subprovince extends from Drummond Point to
Cape Catastrophe on south-western tip of Eyre
Peninsula, and represents a coastal distance of
approximately 300 km.
THE EYRE COAST
The Eyre Coast is the largest coastal
geomorphological region in South Australia,
extending over 1,300 km, from the head of the Great
Australian Bight (ie. from the West Australian
border) to the entrance of Spencer Gulf (ie. to Cape
Catastrophe on Eyre Peninsula). Compared to the
rest of the State, this region contains some of the
most remote, uninhabited, and rugged coastal
regions of South Australia. Along this highly
variable coastline there are spectacular cliffs and
headlands, numerous offshore islands, surf pounded
beaches and small sheltered embayments. Many of
the offshore islands in this region provide important
breeding and haul out sites of the rare Australian Sea
Lion and the New Zealand Fur Seal. For the most
part however, this extensive coastline faces the full
force of the Southern Ocean and as such,
experiences some of the highest wave energies in the
State.
1.1 Biogeography of the Eyre Coast
Along the southern coast of Australia, marine
biogeographers recognise a major biogeographic
region, known as the Flindersian Province, which
extends from southwest Western Australia to
southern New South Wales and includes the waters
of Victoria and Tasmania. Within this broad
region, the coastal waters of the Great Australian
Bight are recognised as warm to cool temperate (in
contrast to the cold temperate waters of the
southeast of Australia, west of Robe).
Within the geomorphological province known as the
Eyre Province, 6 distinct coastal subprovinces have
been recognised (Short et al. 1986):
−
Nullarbor Cliffs - this subprovince extends
from wilson Bluff on the border of Western
Australia, to the Head of Bight, and represents a
coastal distance of approximately 209 km .
Within the Flindersian Province, the Eyre Coast
region (including the Nuyts Archipelago, Pearson
Isles, Whidbey Isles) encompasses 3 finer-scale
mesoscale biogeographical regions or bioregions
have been recognised (IMCRA 1997):
1
2
3
Eucla – extending from Israelite Bay (WA) to
Cape Adieu (SA).
Murat – extending from Cape Adieu to Cape
Bauer.
Eyre – extending from Cape Bauer to Salt
Creek, to Corny Point, to West Cape (Spencer
Gulf), to Cape Borda (Kangaroo Island).
Within this variable region, a further 11 smaller
scale biounits (ie. 9 inshore biounits and 2 offshore
island biounits), have been recognised:
1
Nullarbor – encompassing the Nullarbor
Cliffs, extending from Israelite Bay (WA) to
the Head of the Bight.
Page 2
EYRE REGION
2
Wahgunyah –extending from Head of the
Bight to Cape Adieu.
3
Fowlers – encompassing Fowlers Bay,
extending from Cape Adieu to Point James.
4
Nuyts – encompassing the offshore Nuyts
Archipelago, from Point James to Cape
Bauer.
5 Streaky – ecompassing the inshore
embayments from Point James to Cape Bauer.
6
Yanerbie – extending from Cape Bauer to
Taila Caves.
7
Newland – extending from Talia Caves to
Cape Finnis, encompassing the Newland
Barrier.
8
Flinders – encompassing the offshore
Investigator Group, Flinders Isles and Pearson
Isles.
9
Sheringa – encompassing the Sheringa
Lagoon, extending from Cape Finnis to Point
Drummond.
10 Douglas – extending from Point Drummond
to Point Sir Isaac, encompassing Port Douglas
and Coffin Bay.
11 Whidbey – extending from Point Sir Isaac to
Cape Catastrophe, encompassing the Whidbey
isles, southern Eyre, Coffin Bay and Jussieu
Peninsulas.
2
OCEANOGRAPHY
Tides along the Eyre coast are microtidal in range
and are predominantly semi-diurnal with a marked
diurnal inequality between the two daily tides.
Tides on the Great Australian Bight (western Eyre
Peninsula) are semi-diurnal, with a mean tidal
range of between 0.8 and 1 m. In southern Spencer
Gulf they are of a similar range but are of a mixed
type.
2.2 Water Temperature and Salinity
Salinities and temperatures along the western coast
of Eyre Peninsula generally vary according to the
water masses that prevail in the Bight region.
As such, four major water masses have been
identified:
−
the Leeuwin Current, which has low salinities
(35.0%) and high temperatures;
−
the central Bight water mass from the southeast Indian Ocean, which has high salinities
(35.4-36.0%), and warmer temperatures (1721oC);
−
the West Wind Drift cold water mass has low
salinities
(35.0%-35.6%)
and
lower
temperatures (9-14oC); and
−
the surface-flowing Flinders Current, which has
a mean salinity of 35.35% and a mean
temperature of 14oC.
2.1 Wave Climate
The Eyre Coast is located within the `west coast
swell environment' where coastal processes are
dominated by a persistently high south-west swell,
generated by the westerly moving low pressure
cyclones south of the mainland (Davies 1980). This
south-west to westerly swell ranges from less than 2
m for 50% of the year, to 2-4m for 30-45% of the
year and exceeding 4 m approximately 10% of the
year. Wind generated sea conditions also provide an
additional source of wave energy, with seas
averaging 0.5 to 1.25 m and may exceed 2 m for 1015% of the year.
Breaker wave energy varies considerably along the
coast. Land-locked bays and sheltered areas
experience low breaker wave energy with local
wind waves influencing energy regimes. Such
areas include Coffin Bay, Venus Bay, Baird Bay,
parts of Streaky Bay, Smoky Bay, and Tourville
Bay. The open coast, however, is typified by a
high deepwater wave climate and a highly variable
breaker wave climate due to differences in
nearshore-offshore gradients.
Advective processes influence and control the
salinity distribution across, and within, shelf waters.
Some additional mixing is brought about by the
reversal in direction of a easterly-south-easterly flow
in winter, to a westerly-north-westerly flow during
November to March.
2.3 Currents and Upwellings
Currents
Four major water masses influence the
oceanography of the eastern part of the Great
Australian Bight. These water masses generally
occur for all or part of the year within the continental
shelf and slope region off southern Australia:
−
the Leeuwin Current, which originates from the
tropical waters of the Indian Ocean. This water
mass carries warm water with low salinity
along the continental shelf break as far east as
130oE and passes from west to east
predominantly (though not exclusively) during
winter from May to September-October
(Rochford 1986).
Page 3
EYRE REGION
However, it is possible there is a reversal of
flow in the summer with the current setting to
the west along the south coast and to the north
on the west coast (Rochford 1969).
−
a warm and very high salinity water mass,
which occurs in the central and eastern half of
the Great Australian Bight for most of the year.
This central Bight water mass drifts to the
south-east and occupies much of the shelf and
slope region east of 135oE, particularly in
winter (Rochford 1986).
−
a West Wind Drift cold water mass of lowest
salinity, which is found throughout the year off
the slope region of southern Australia and
periodically intrudes into the shelf break,
especially when the Leeuwin Current is weakly
developed (Rochford 1986).
−
and the surface-flowing Flinders Current,
which originates from the gyre south of South
Australia (Bye 1972). These mixed waters
have an average surface flow velocity of about
5cm sec-1.
3
CLIMATE
The climate of the Eyre Peninsula coast is typically
semi-arid or `Mediterranean' and as such, is
characterised by hot, dry summers and cool, moist
winters. It is largely influenced by mid-latitude
anticyclones or high pressure systems which pass
from west to east across the continent. Winter
generally brings southerly to southeasterly winds
and low pressure systems which travel across the
Southern Ocean between 40 and 50oS, bringing
frontal activity and rain. Summer brings northerly to
northwesterly winds. Along the Great Australian
Bight and the western coast of Eyre Peninsula,
strong westerly, onshore winds have reworked the
coast, resulting in extensive dune development.
Most rainfall falls during winter, however it varies
considerably with latitude, from approximately 500
mm in the south to less than 300 mm in the north.
4
COASTAL GEOMORPHOLOGY AND
LANDFORMS
Upwellings, by providing nutrients to surface
waters, are sites of significant productivity. Along
the Eyre Province, a periodic upwelling has been
identified off the coast of western Eyre Peninsula
and is characterised by an ephemeral temperature
inversion within the shelf waters, south of Eyre
Peninsula, during October and November (Wenju
et al. 1990).
The coast geomorphology is highly variable along
the Eyre Coast with many islands, rocky headlands,
embayments and surf pounded beaches (see Short et
al. 1986, for review). This variability is a result of
the continual changes in orientation and degree of
protection of the coast from wave attack. The
generally low summer rainfall coupled with a
limestone (calcarenite) dominated coast has resulted
in no rivers and only a few intermittent streams
arriving at the coast. As a result there are no true
estuarine environments in this province.
Open coast sea temperatures vary from a mean
summer sea surface temperature of 18oC to a mean
winter sea surface temperture of 14oC. The inshore
coastal regions are under the influence of seasonal
coldwater, nutrient-rich coastal upwellings which
occur close to the coast, which can result in an
offshore sea surface temperature gradient of 18oC to
inshore temperatures of 11oC in inshore areas during
the summer months (Ward & McLeay 1998). The
region from Point Sir Isaac (Coffin Bay Peninsula) to
Cape Borda (Kangaroo Island) appears to be the
major focus of the coastal upwelling. There appears
to be a relationship between the upwellings, and the
pilchard numbers in these areas (Ward & McLeay
1998). There is also a potential link with the
abundance of seabirds, seal and sea lion abundance in
the region.
The major open coastal landforms can be divided
into rocky and sandy sections. The rocky sections
consist of Tertiary limestone cliffs (with the largest
section being 178 km long), Precambrian bedrock
(usually capped by dune calcarenite); and
Pleistocene dune calcarenite which is exposed in
cliffs up to 150 m high, usually fronted by well
developed shore platforms and reefs. The sandy
sections include numerous beaches with backing
foredunes and transgressive dunes, finer sediments
composing some bay shores and usually vegetated
with mangroves; and lagoonal deposits. The sandy
and rocky sections are often found together, with
beaches fronting stranded dune calcarenite cliffs,
reefs commonly occurring off beaches, and many of
the dune calcarenite cliffs capped by Holocene
clifftop dunes.
Upwellings
Page 4
EYRE REGION
Large coastal embayments occur at Coffin, Streaky,
Smoky and Denial Bays. Semi-enclosed bays occur
at Port Douglas, Venus, Baird and Tourville Bays.
Open bays with broad entrances but protected by
islands, reefs and shallow gradients occur at Coffin,
Sceale, Streaky, Smoky, Decrees and Denial Bays.
Open bays that are largely protected by sand barriers
with only narrow inlets or entrances occur at Port
Douglas, Venus, Baird and Tourville Bays. These
bays contain extensive tidal delta deposits. Smaller
bays include the area in lee of Cape Missiessy and
Acraman Creek.
Peter Island are the only oceanic stand on the entire
South Australian coast. The relatively low total area
of mangroves along the Eyre Coast is a result of the
exposed conditions of the coast. Along the exposed
sections of the Eyre Coast, mangroves are also found
within the sheltered confines of the semi-enclosed
Venus Bay.
Numerous saline lakes have formed along the
coastal areas and often occur in lee of many of the
sand barriers, including the Newlands barrier,
Sheringa and Cactus Beach. These lakes form
because of a lack of fluvial input, periodic
freshwater flooding and high evaporation rates.
The subtidal habitats of the Eyre Coast have not, until
recently, been systematically surveyed. However,
within the region, detailed survey reports have
previously been published for Pearson Island
(Shepherd and Womersley 1971), the St Francis Isles
(Shepherd and Womersley 1976), and Waterloo Bay
(Shepherd and Womersley 1981). Further, algal
distribution records from sporadic collecting in the
following areas of the West Coast, have been lodged
with the SA Herbarium during the past three decades:
Point Fowler and Nuyts Reef (Shepherd and
Womersley 1980, unpubl. report), Waterloo Bay
(Shepherd, 1978; Shepherd and Turner 1982);
Waldegrave Island (Shepherd 1978; Branden 1987);
Pearson Island (Specht 1960; Shepherd 1982);
Topgallant Island and “The Hotspot” (Shepherd and
Gray 1982; Branden 1987; O’Leary 1992), Ward
Island (Shepherd 1980 and 1982; Graske, no date);
Sheringa Bay and West Point (Shepherd 1969).
Many offshore islands and numerous reefs are
scattered within this province.
Of particular
geological significance is the Investigator Group of
Islands (particularly the Pearson Islands) which are
true granitic inselbergs (island mountains). Granitic
plains and inselberg landscapes are also found
around Baird Bay.
5
BIOLOGY
5.1 Intertidal Ecology
A diverse range of marine habitats are represented
along the Eyre Coast. These include: cliffs; rocky
shores; platform reefs; sandy beaches; offshore
islands; subtidal reefs; seagrass meadows, small
mangrove stands (Avicennia marina); sand and mud
deltas.
The general intertidal ecology of the Eyre Coast has
been summarised by Womersley and Edmonds
(1958) and more recently by Womersley (1991). It is
possible to summarise the major assemblages and
communities present according to the wave regime
experienced in the area. This is by no means
definitive, however, as local variations will occur:
1
2
3
3
Coasts of slight wave action, with sandy or
muddy flats or beaches:
Sheltered coasts of moderate wave action:
Coasts of strong to extreme wave action (eg.
steeply sloping intertidal regions of granite at
Point Sinclair and Cape Carnot):
Horizontal intertidal rock platforms.
Mangroves (Avicennia marina) are only found in
sheltered creeks or the lee of island spits at Tourville
Bay (15 km2), Eyre Island (5 km2), Acraman Creek
(5 km2), Laura Bay (0.5 km2) and St Peter Island (2
km2). The mangroves of Tourville Bay are of
particular note as they form the westernmost stand in
South Australia and the western most on the entire
southern Australian coastline. The mangroves of St
Intertidal rocky shores in the region are dominated in
the sublittoral fringe by Cystophora intermedia.
5.2 Subtidal Ecology1
Rocky shores along the Eyre Coast are typically
dominated by highly diverse subtidal macroalgal
communities. Along exposed coasts, these comprise
diverse red algal assemblages (dominated by
Osmundaria, and species of Plocamium), and green
algae (eg. species of Caulerpa), and also, large
brown canopy-forming algae, such as Ecklonia
radiata, and Cystophora species (eg. C. monilifera,
C. moniliformis and C. platylobium).
Generally, benthic biological information for the
Eyre Coast, especially the Great Australian Bight, is
poor, due to the remoteness and ruggedness of the
area. While recent surveys by SARDI have given
researchers a better understanding of the subtidal
macrofloral and habitats of the region, there still
remains a paucity of information on invertebrates,
fish and seabirds. The following is a recent detailed
account of the major marine habitats and plant life in
the region by Edyvane and Baker (1998).
1
From Edyvane KS & JL Baker. (1998). Marine Biogeography of
the Eastsern Great Australian Bight.
Page 5
EYRE REGION
communities typical of southern Australian coasts.
Eucla Bioregion (eastern Great Australian
Bight)
The subtidal habitats of the Eucla Bioregion (from
west of Cape Adieu), reflects both the high wave
energy and the geology of the high-cliffed eastern
Great Australian Bight and surrounding regions.
Much of the area from the cliff line to 20m deep
comprises bare sand stretches along the coast, with
patches of calcarenite and crystalline basement rock
reef (ie. granite) (Edyvane and Baker 1996). The
Eucla Bioregion is one of low benthic biodiversity,
with a total of only 11 species of macroalgae
recorded from sites sampled at the Head of the Bight
and Collosity Point, compared with an average of
between 30 to 40 species along other areas of the
Eyre Coast. Several reef areas within the Eucla
Bioregion (Pilpuppie Well, Nuyts Reef) and in the
western Murat Bioregion between Cape Nuyts and
Point Bell (including the reef area in the middle of
Fowler Bay), contain a diverse understorey of large
red algal species, such as Amansia pinnatifida and
Dictymenia, and mixed articulate corallines.
Most of the reef areas in the Eucla Bioregion (and
western section of the Murat Bioregion) are exposed
to the strong south-westerly swell, high wave
climate, and influenced by the relatively nutrientpoor, warm water (from the Leeuwin Current) which
characterise the Head of the Bight region of the Great
Australian Bight, and these sites usually contained
algal assemblages typical of such oceanographic
conditions, such as stands of Ecklonia and
Scytothalia, few other macroalgal species, and an
encrusting coralline understorey.
The fucoids,
Cystophora racemosa and C. grevillei also thrive in
this region, with C. grevillei plants often growing
more than 1 metre tall.
The Head of Bight region is one of relatively low
algal diversity and high dominance of a few major
reef species. Two macroalgal brown genera
dominate the benthos at the Head of Bight and
Collosity Point - Ecklonia and Scytothalia, the former
comprising 40 - 50% of the cover in most areas at the
Head of Bight. A significant portion of the surface
cover on reefs in this region (ie. 40-50%) is also
encrusting coralline algae. At the Head of Bight
region, low numbers of both red and brown algal
species have been recorded, and both seagrass and
green algae are generally poorly represented or
absent in the exposed areas.
Oceanographic
conditions, such as the existence of strong swell
and wave conditions for most of the year, possibly
restricts the establishment of flora on the large
expanses of bare, mobile sand between reef
patches. The existence of warm water masses in the
Bight may alos be responsible for the low diversity
of algal species in this region, compared with
cooler regions of nutrient-rich upwelling further
east in the Eyre Bioregion, which permit the
establishment of more the more diverse floral
The benthic species composition at Cape Adieu is
very similar to that at the Head of Bight, apart from
the presence of Cystophora grevillei as a subdominant, which has been recorded only at the
headlands of Cape Adieu and Cape Nuyts. Whilst
areas within the Eucla Bioregion comprised mainly
Pleistocene dune calcarenite reef with Ecklonia or
Scytothalia as the dominant macroalgal cover and
encrusting corallines as the dominant understorey
cover, the flora of Pilpuppie Well encompasses a
more diverse understorey of red algae than other
areas within the Eucla Bioregion. Cape Nuyts and
Nuyt’s Reef, at the boundary of the Eucla and Murat
Bioregions, are similar in dominant phaeophyte cover
to other areas in the Eucla Bioregion, although
Cystophora species were more prevalent as subdominants, and encrusting coralline species are a less
dominant feature of the understorey. Relatively high
species diversity of red macroalgae has been
recorded at Nuyt’s Reef, including Areschougia and
Pterosiphonia (sp. nov.). The high diversity of red
species at Nuyt’s Reef concurs with Shepherd and
Womersley’s (1980) findings of a reef which is “rich
in species” (however the site was compared only
with Point Fowler).
Murat Bioregion (Far West Coast)
The Murat Bioregion (from Cape Adieu to Cape
Bauer), encompasses several major sandy bays and
numerous smaller embayments, receiving low wave
energy; and exposed peninsulas, headlands and
islands mainly composed of Pleistocene dune
calcarenite over Precambrian crystalline bedrock
(Edyvane 1995). Many islands also exist in the
region, most consisting of crystalline basement rock
capped with calcareous aeolianite. Seagrass-lined
bays in the Murat Bioregion include the inner parts of
Fowler Bay (dominated by Posidonia sinuosa and
Amphibolis antarctica), Murat Bay (Posidonia
community in the eastern and western parts of the
bay, and Heterozostera community in the northern
part); and Bosanquet Bay (mixed Heterozostera,
Posidonia and Halophila communities). These bays
also support substantial areas of seagrass and
scattered stands of mangroves (Avicennia marina)
which provide habitat for estuarine and coastal fish
stocks. The deeper part of Fowler Bay (eg. 16m)
comprise reef, partly covered with an unusual floral
assemblage of dense red algae such as Amansia
pinnatifida, Osmundaria, Amansia keutzingioides,
Vidalia, Champia and other red genera. Scaberia and
Sargassum species are also recorded here, as minor
components of the benthic cover, but unlike other
reef areas along this coast, no brown algae are
dominant as reef flora. The Fowlers Bay area is a
region of high red macroalgal diversity (ie. 52 red
species). This contrasts with Shepherd and
Womersley’s (1980) conclusion that the benthic
habitats around the Point Fowler area are
characterised by a “paucity of species” (purportedly
Page 6
EYRE REGION
due to the lack of upwelling of cool water in this
coastal region compared with sites further offshore).
Eyre Bioregion (Western & Southern Eyre
Peninsula)
Exposed areas in the Murat Bioregion, such as Point
Bell, have floral affinities with areas in the Eucla
Bioregion (ie. reefs are dominated by Scytothalia and
Ecklonia, with a coralline understorey), while Point
Bell Bay contains both seagrass communities
(Posidonia and Amphibolis) and diverse red algal
assemblages. The highest diversity of red macroalgae
in the region occurs at Point Bell Bay (ie. 67 species,
dominated by Osmundaria, but also including
Dictymenia, and Amansia, and filamentous red
epiphytic species such as Dasya, Herposiphonia and
Micropeuce.
The western Eyre Bioregion (from Cape Bauer to
Cape Catastrophe) is characterised oceanographically
by a moderate to high, deep water wave energy
coastline (Edyvane 1995). During the late summer
months, the warm temperature waters of the south
west coast of Eyre Peninsula are subject to localised,
cold, nutrient rich upwellings (Wenju et al. 1990).
The coastal geomorphology of the western Eyre
Bioregion is highly variable, resulting from changes
in orientation and degree of protection of the coast
from wave attack (Short et al. 1986). There is a
diversity of major coastal and marine habitat types in
the Eyre Bioregion, including cliffs, rocky shores,
intertidal platform reefs, sandy beaches, offshore
islands, subtidal reefs, seagrass meadows, small
mangrove stands, and sand and mud tidal deltas (eg.
Venus Bay). Within the western Eyre Bioregion there
are many offshore islands and numerous reefs, such
as the Investigator Group of islands, which are true
granitic inselbergs and thus of geological significance
(eg. Pearson Islands) (Edyvane 1995).
In the less exposed areas of the Murat Bioregion, in
the lee of the Nuyts Archipelago (protected from the
full force of the south-westerly swell conditions), reef
communities generally contain higher floral diversity.
Reef areas in the Murat Bioregion, such as Cape
D’Estrees, Franklin Island and Cape de Mole, are
characterised by mixed Cystophora and Sargassum
species, Osmundaria and/or often a diverse
understorey of mixed red species. Further east, in the
Eyre Bioregion, more temperate, cooler water species
occur, such as Acrocarpia and the rough-water,
south-eastern species of Cystophora, C. platylobium,
occur with mixed red understorey assemblages
dominated by Plocamium and Phacelocarpus
species. The large brown Acrocarpia paniculata is
generally uncommon on the eastern Great Australian
Bight - western Eyre Peninsula coast, but is a major
component of reef flora at cooler water locations
such as the southern end of Eyre, Yorke and Fleurieu
peninsulas.
The benthic habitats in shallow (5m) waters off Cape
D’Estrees are mainly characterised by stands of
mixed Sargassum species over sponge beds,
interspersed with Posidonia sinuosa meadows. At the
ecologically significant Franklin Islands, the exposed
western side at 15m contains a reef floral assemblage
similar to the exposed areas in the Eucla Bioregion,
dominated by the fucoid Scytothalia, with an
understorey of encrusting coralline algae. In contrast,
the less exposed eastern side of the Franklin Islands
are characterised by a reef community of mixed
Sargassum and Cystophora species, similar to the
reefal area off Cape D’Estrees, to the north. The
Franklin Islands region contains a great diversity of
brown algae (ie. 24 species, including 9 species of
Sargassum). Uncommon species at the bioregional
level, such as the red algae, Trigenia umbellata and
T. australis form a significant component of the
habitat in areas on the eastern end of the Murat
Bioregion (ie. Cape de Mole and Cape Bauer). Cape
de Mole is notable for 6 species of green algae
(higher than the number of Chlorophytes recorded at
any other site in the eastern Great Australian Bight),
and by the apparent local abundance of the rare
brown alga Scoresbyella profunda).
Whilst the region is mainly characterised by
temperate Flindersian elements, such as Ecklonia
radiata and Cystophora species, the upwelling may
explain the common occurrence in this bioregion of
diverse, cooler water, red algal communities
dominated by mixed Plocamium and Phacelocarpus
species, and the occurrence of more easterly (cooler
water) brown macroalgae, such as Acrocarpia
paniculata. Red algae dominate the benthos on
coralline-covered reef sites, particularly at Weyland
Point (seaward of Venus Bay) and Point Whidbey, in
the far south of the region. The large red algae
Osmundaria forms the main cover on many reefs (eg.
Anxious Bay), where it occurs with an understorey of
mixed red species such as Phacelocarpus and
Plocamium costatum and P.dilatatum. The cooler
temperate brown algae Acrocarpia paniculata
occurs as a reef dominant in this region (eg. at
Weyland Point and also, along the southern end of
Eyre Peninsula, at Liguanea Island). The reefs of
Liguanea Island also comprise a dense understorey of
mixed hydroids and ascidians.
Shallow, sheltered bays in the region, such as Venus
Bay, are dominated by the seagrass Heterozostera,
along with mixed Cystophora species, such as C.
siliquosa and C. monilifera. Other more exposed
bays in the region, such as Searcy Bay, are
dominated by a rich assemblage of mixed red, green
and brown algae, such as Phacelocarpus and
Plocamium species, Caulerpa flexilis, and
Homeostrichus, which form a dense understorey. The
green Caulerpa species C.flexilis and C.obscura were
also dominant at Point Labatt, where the understorey
comprises mixed red and brown species similar to
Searcy Bay.
Page 7
EYRE REGION
5.3 Fish
The marine fish fauna found in the waters
surrounding Eyre Peninsula is typical of the
Flindersian Province of southern Australian coastal
waters (Glover & Olsen 1985). As such, many of
the species recorded in South Australian waters,
have also been recorded in southern and southwestern Western Australian waters, and to a lesser
extent, in the waters of western Victoria and northwest Tasmania.
For instance, Hutchins and
Thompson (1983) reported that of the 344 species
they listed for south-western Western Australia, 61%
extended eastwards to, at least, off South Australia.
There are some 300 species of known marine fish
recorded off Eyre Peninsula down to the base of the
continental slope, which represents approximately
67% of the species recorded from all South
Australian marine waters (Glover 1982).
Most of the species along the Eyre coast tend to be
inshore with fairly permanent resident populations.
However, there are some regular migratory visitors
such as the Australian Salmon and occasional
oceanic vagrants such as oceanic Sunfish (Mola sp.),
Basking Shark (Cetorhinus maximus), Black Marlin
(Makaira indica), and the Lizardfish (Saurida
undosquamis). Their presence in these waters can
be attributed to the easterly flowing Leeuwin
Current (Glover & Olsen 1985).
Among the native freshwater species, which spend
part of their life cycle at sea - the Common Galaxias
(Galaxias maculatus) and the Black Bream
(Acanthopagrus butcheri), have been recorded in the
Tod River. The Common Galaxias has also been
recorded in the North Shiels Creek, Lake Wangary
and a tributary of Little Swamp (Glover & Olsen
1985). Small-Mouthed Hardyhead (Atherinasoma
microstoma) have been recorded in the permanent
spring-fed saline waters of Lakes Hamilton and
Newland, on the west coast south of Venus Bay,
while eleven normally marine species of fish have
been recorded in Lake Wangary, which has a
connection with the sea via Minniribbie Creek.
Marine and primarily marine species are likely to
enter and frequent the estuaries and lower reaches of
other coastal waterways, eg. the Congolli
(Pseudaphritis urvillii).
However, most seaconnected waterways occur along the east coast of
Eyre Peninsula in the Gulfs Province.
bellied Sea-eagle, Sooty Oystercatcher, Pacific Gull,
Fairy Tern, Crested Tern, Rock Parrot, and the
Fleshy-footed Shearwater (Smith Island) (Eckert et
al. 1985). The Australian Raven breeds on myallbluebush plains and on islands off the western coast.
Some of the islands are home to colonies of rare or
nearly extinct birds. For instance, the Southern
Stone Curlew, which is found on Thistle and Boston
Island, is largely extinct as a breeding bird on the
South Australian mainland. There are also large
breeding grounds for the Cape Barren Goose off the
west and south coasts and on the Sir Joseph Banks
Group (Robinson et al. 1982).
Other species breed on more protected, inshore
islands along the Eyre coast. Goat Island in Coffin
Bay, is of particular significance in being one of the
most accessible South Australian breeding grounds
of the Rock Parrot. The ABC islets in Venus Bay
also carry breeding populations of this species and
together with Jones Island and Little Eyre Island are
of further significance for their breeding colonies of
the Australian Pelican. Another local breeding bird
of sheltered islands is the Eastern Reef Egret (Eckert
et al. 1985).
5.5 Marine Mammals
The Eyre Coast is home to many species of marine
mammals, particularly, cetaceans. At least 17
species of cetaceans have been recorded in the
Great Australian Bight, and of these at least one,
the Southern Right Whale, is known to calve in the
area during May to November (Kemper & Ling
1991). Some species are migratory, such as Blue
Whales, Sperm Whales, Minke Whales,
Humpbacks, Rorquals, as well as the endangered
Southern Right Whale. Their presence may be due
to the squid that are believed to be abundant in the
Ceduna canyons and just off the continental shelf
(Kemper & Ling 1991). Killer Whales have also
been recorded and their presence is probably
related to the abundance of pinnipeds along the
western Eyre Peninsula. The Head of Bight, in
particular, is an important calving, nursing and
breeding area for Southern Right Whales. This
may be due to the warmer waters brought in by the
Leeuwin current since cetaceans are born with little
blubber.
5.4 Seabirds
There are many birds that breed wholly or largely on
the offshore islands of South Australia (including
those located along the Eyre Coast). These include
the Little Penguin, Short-tailed Shearwater, Whitefaced Storm Petrel, Black-faced Shag, Eastern
Reef Egret, Cape Barren Goose, WhitePage 8
EYRE REGION
The warm Leeuwin current has also been suggested
as a mechanism for bringing occasional individuals
of tropical species such as Bryde's Whale into
South Australian waters (Kemper & Ling 1991).
Pelagic organisms, such as the phytoplankton and
zooplankton in the Great Australian Bight, have also
been classified as having tropical origins (Markina
1976).
In addition to cetaceans, the Eyre Coast,
particularly the offshore islands, also contains
significant colonies of the New Zealand fur seal
(Arctocephalus forsteri) and the rare Australian sea
lion (Neophoca cinerea). By extrapolating from the
number of sea lion pups found in the 1994 survey,
the population of the Great Australian Bight region in
South Australia has been estimated at between 613
and 744, which represents approximately 9.3% of the
South Australian population or 6.6% of the total
world population for this species (Dennis &
Shaughnessy 1996).
The significance of the
populations of Australian sea lions in the Great
Australian Bight is further increased because it is
very likely that the populations were never
commercially harvested - like many other
populations along the southern coasts and islands of
Australia last century. Generally, to the point of
extinction. This is principally because of the
isolation and general inaccessibility of the Great
Australian Bight coast, both, from land and sea.
Thus the populations have remained intact, providing
probably one of the greatest sources of genetic
diversity for this species in the world, and also, a very
important genetic and geographic bridging
population between the South Australian and
Western Australian sea lion populations (Dennis &
Shaughnessy 1996).
The existence of a distinct tropical element in the
fauna and flora of the Great Australian Bight is
thought to be due to the Leeuwin Current, bringing
pelagic species and larvae from other regions [see
below]. The distribution of such tropical benthic
fauna due to dispersal by the Leeuwin Current
underlines the difficulty in applying biogeographic
boundaries to biological systems.
MARINE CONSERVATION VALUES
1
SIGNIFICANT
BIOLOGICAL
PHYSICAL FEATURES
AND
1.1 Biological
Tropical Element in the Demersal and Pelagic
Fauna of the Great Australian Bight
The fauna and flora of the Great Australian Bight
region is marked by a characteristic tropical element.
Among the benthic invertebrate fauna, many of the
echinoderm species recorded from South Australia
originate from the Indo-Pacific region (Maxwell &
Cresswell 1981). For instance, some 20 of the 84
species of hydroid recorded from South Australia
have their principal distribution in the warm waters
of the Indo-Malay region. Other echinoderms of
Indo-Pacific origin include the Basket Star (Euryale
aspera), and the holothurians, Pentacta anceps and
Pentacta quadrangularis (Maxwell &
New Zealand Fur Seal (Arctocephalus
forsteri) and the rare Australian Sea Lion
(Neophoca cinerea)
Both the New Zealand Fur Seal (Arctocephalus
forsteri) and the rare Australian Sea Lion (Neophoca
cinerea) have significant breeding colonies in South
Australia. The largest colonies of these two resident
mammals occur on the islands off Eyre Peninsula
and represent a major proportion of the world
population for both these species (Watt & Ling
1985). Dangerous Reef in southern Spencer Gulf, in
particular, is one of the three major breeding areas
for Australian Sea Lions in South Australia (Watt &
Ling 1985, Robinson & Dennis 1988, Gales 1990,
Gales et al. 1994). Other major breeding areas for
this species in this region include Purdie, Olive and
Franklin Islands (Nuyts Archipelago). Further, Point
Labatt near Streaky Bay represents the only and
largest mainland colony of Australian Sea Lions in
Australia.
The Neptune Islands are one of three major breeding
areas of New Zealand Fur Seals in South Australia
(along with Kangaroo Island and the islands off the
Jussieu Peninsula). Together the fur seals from the
Neptune Islands comprise almost 13,800 seals and
represent approximately 61% of the estimated South
Australian population or 51% of the total Australian
population for this species (Shaughnessy 1990,
Shaughnessy et al. 1994).
The islands of the Nuyts Archipelago and Sir Joseph
Banks Group (Spencer Gulf) have smaller but
nevertheless important colonies of Fur Seals and Sea
Lions, and breeding also takes place at some of these
sites. However, there is considerable mobility
between haul-out sites.
Cresswell 1981).
Page 9
EYRE REGION
Southern Right Whales (Eubalaena australis)
The Eyre Coast (and Great Australian Bight) is a
region of world significance for the breeding of the
endangered Southern Right Whale (Eubalaena
australis). Along this coast are located the three
critical nursery areas for calving and mating of
Southern Right Whales in South Australia:
Moodyara, Twilight Cove and the Head of the Bight
(Ling & Needham 1991). At least 40 -50 whales
visit the Head of the Great Australian Bight between
May and November each year. They usually
frequent the waters within 1 km offshore, and are
easily seen from the coastal cliffs. Calving occurs in
June and nursing continues until November. Mating
may also occur during this time. Whales seen in
South Australian waters one year have been sighted
in Western Australia during another year, suggesting
that the whales may "home in" on different areas
according to particular phases of their reproductive
cycle (Ling & Needham 1991). The varied shoreline
with its embayments and protected waters are
probably important for shelter in adverse weather
and may be calving grounds for some species
(Kemper & Ling 1991).
Other Cetaceans
The Great Australian Bight region generally is also
becoming increasingly recognised as a significant
seasonal habitat for many other species of rare and
endangered marine mammals. At least 17 species
of cetaceans have been recorded including Blue
Whales, Sperm Whales, Minke Whales, Rorquals
and Humpbacks (Kemper & Ling 1991). In the
National Cetacean Action Plan (Bannister et al. in
press), the Blue Whale (Balaenoptera musculus
musculus) is listed as `endangered’, the Humpback
Whale (Megaptera novaeangliae) is `vulnerable’,
while the Sperm Whale (Physeter macrocephalus)
is listed as `insufficiently known’ and `potentially
vulnerable’ under the IUCN Red List categories.
Blue, Sperm, Minke (Balaenoptera acutorostrata)
and Humpback Whales are reasonably commonly
sighted, aswell as stranding around the Great
Australian Bight. Possibly resident cetaceans are
the Beaked Whale, Killer Whales (Orcinus orca)
and Risso’s Dolphin (Grampus griseus).
Individuals of tropical species such as Bryde’s
Whale (Balaenoptera edeni) are occassionally seen
in South Australian waters, and it has been
suggested that they have travelled on the warm
Leeuwin Current (Kemper & Ling 1991).
Bottlenose Dolphins (Tursiops truncatus) have
been seen on many occasions playing amongst
Southern Right Whale groups (Ling & Needham
1988, Bannister 1993).
The presence of cetaceans, particularly Killer
Whales (Orcinus orca) is probably related to the
abundance of pinnipeds along the western Eyre
Peninsula. Owing to its remoteness and ruggedness
of the Bight region, this area has not been studied in
any detail. As such, there is generally a paucity of
biological information.
Fauna and Flora of the Offshore Islands
There are 47 islands between Cape Catastrophe and
the islands of the Nuyts Archipelago. The major
groups are the Whidbey Islands, the Investigator
Group which includes the relatively large Flinders
Island (25km2), and Nuyts Archipelago. They are
important because most are undeveloped and
uninhabited, thus providing important habitats and
ecological refuges for species which have become
extinct on the mainland. Some of the islands of
particular conservation significance include the
Franklin Islands (Nuyts Archipelago) which contain
the last known population in the world of the Greater
Stick-nest Rats (Leporillus conditor); St Francis,
Purdie, Lounds, Olive and the Neptune Islands
which contain significant breeding colonies of rare
Australian Sea Lions and New Zealand Fur Seals;
the Eyre Islands which contain completely
undisturbed vegetation including mangroves and
samphire flats; and St Peter Island which also
contains significant stands of mangroves, as well as
re-introduced populations of Stick-nest Rats and
Brush-tailed Bettongs, and a spectacular 4 km long
sand spit in lee of the island.
Coastal Wetlands of National Importance
A Directory of Important Wetlands in Australia
(ANCA 1996) list the following coastal wetlands of
national importance along the Eyre Coast:
1
2
3
4
5
6
7
Davenport Creek
Streaky Bay
Point Labatt
Baird Bay
Lake Newland
Lake Hamilton
Coffin Bay Coastal Wetland System
Page 10
EYRE REGION
Extensive Seagrass Meadows
The sheltered embayments of the Eyre Coast,
particularly Streaky and Smoky Bay (ie. Streaky
Biounit), and Port Douglas (ie. Douglas Biounit),
support extensive seagrass meadows. These
extensive seagrass meadows flourish in shallow
clear waters, generally in waters less than 15m, and
provide the basis for the significant productivity of
the coastal regions in terms of fisheries and prawn
production.
Seagrasses cover a total area of
approximately 86,163 ha in Streaky and Smoky Bay,
and 8,567 ha in Port Douglas. Together, the
seagrasses of the Eyre Coast represent approximately
15% (ie. 1,407 km2) of the total area of seagrasses
recorded in South Australia (ie. 9,612 km2).
Seagrass meadows are particularly important for a
number of reasons: as primary producers they occupy
the base of the food chain; they provide important or
“critical” habitats such as nursery, breeding or
feeding areas for the juveniles and adults of many
fish, crustaceans and other marine animals, including
a large number of commercial species (Bell &
Pollard 1989, Howard et al. 1989); and their
extensive root and rhizome systems stabilise
nearshore sediments and sand banks, enhancing
coastal water clarity and reducing coastal erosion
(Scoffin 1971). Seagrass meadows also support a
prolific skeletal biota as infauna and epiphytes,
which in turn, provides the carbonate basis for
sediments in the region.
Mangrove and Coastal Saltmarshes
The sheltered embayments of the Eyre Coast (ie.
Tourville Bay, Murat Bay, Denial, Bosanquet,
Smoky Bay, and Streaky Bay) contain extensive
areas of tidal wetlands in South Australia (and the
most westerly records of mangrove forests in South
Australia) (Edyvane 1996). Mangrove forests in
the region while small are significant (particularly
in Tourville Bay) as they represent the most
westerly distribution of mangroves in South
Australia, and the largest stands between Spencer
Gulf and Exmouth Gulf in Western Australia.
Associated with the mangrove habitats are
biologically rich mud flats, coastal saltmarshes and
seagrasses. Together, mangrove and saltmarsh
communities along the South Australian coast total
approximately 82,000 ha, with the largest
communities occurring in Spencer Gulf (46,000 ha)
and Gulf St Vincent (20,000 ha). A total of 9 000
ha of mangrove and saltmarsh communities are
recorded on the west coast of Eyre Peninsula
(9,000 ha). Other substantial communities occur
in lower Spencer Gulf (6,000ha), on and on
Kangaroo Island (7,000 ha) (DELM 1993).
Mangrove forests comprise a single species, the Grey
Mangrove, Avicennia marina, which forms a low
woodland forest extending from mean sea level to
spring high-tide level.
Progressively higher
vegetated zones are a Halosarcia-Sarcocornia
(saltmarsh) association, a Sclerostegia-Halosarcia
(saltmarsh) association and an Atriplex (saltbush)
association (Chinnock 1980). These tidal wetlands
are areas of considerable productivity and represent
significant feeding habitats for waterfowl and
waders, and also represent key nursery, feeding and
breeding areas for many economically important
species of fish and crustaceans (eg. Western King
Prawn, King George Whiting, Southern Sea Garfish).
Conspicuous algal mats, which form as a result of
sediment trapping by filamentous blue-green algae
are associated with both, the mangrove and saltmarsh
flora. A variety of marine organisms, mostly
gastropods, bivalves, polychaetes and crustaceans,
also live in and on the mangrove mud, and are a key
food source.
1.2 Physical
Leeuwin Current
The Leeuwin Current is a major eastern boundary
current system off the west coast of Australia. This
warm, low salinity current originates from the
tropical Indian Ocean and during winter from May
to September-October, flows south along the shelf
break of the west coast, along the southern coast of
Australia, to the eastern Great Australian Bight (to
approximately 130oE). For coastal and offshore
fisheries, the Leeuwin Current is intimately linked to
the population dynamics of many of Western
Australia's and to a lesser extent, South Australia's,
commercially important species. As such, the life
history characteristics, such as spawning, migration,
recruitment and feeding patterns, and ultimately the
overall production, of many species along the
western and southern seaboard of Australia have
evolved under the influence of such a current
system. Almost all of the major economically
important fish stocks off the western and southern
coasts of Western Australia are influenced to some
extent by the Leeuwin Current (Lenanton et al.
1991).
Some pelagic species use the Leeuwin Current to
disperse from the north-western waters of Australia
to the southern seaboard of Australia. For instance,
the Southern Bluefin Tuna (Thunnus maccoyii)
spawns in the Java Sea and migrates southward
along the western Australian coastline and eastward
along the southern coast of Australia. It is an
important commercial species and its distribution
and abundance is influenced by the seasonality,
strength and timing of the Leeuwin Current.
Page 11
EYRE REGION
Other commercial pelagic fish whose distribution
and abundance is affected by the Leeuwin Current
include, Mackerel (Scomber australasicus), Horse
Mackerel (Trachurus declivis), Australian Salmon
(Arripis truttaceus), and Australian Herring (Arripis
georgianus). Southern Bluefin Tuna and the latter
two species are particularly important fisheries in
South Australian waters.
In South Australia, the Leeuwin Current also brings
warm waters to the Head of the Great Australian
Bight. Since cetaceans are generally born with little
blubber, this is thought to explain the existence of
several critical breeding areas for the endangered
Southern Right Whale in this region. The warm
Leeuwin current has also been suggested as a
mechanism for bringing occasional individuals of
tropical species such as Bryde's Whale into South
Australian waters (Kemper & Ling 1991).
Coastal Upwelling and
Southern Eyre Peninsula
Productivity
–
Seasonal coldwater, nutrient-rich coastal upwellings,
by providing nutrients to surface waters, are sites of
significant biological productivity. These areas are
often correlated with high levels of productivity
and biodiversity. Along the Eyre Coast, a periodic
coastal upwelling has been identified off the coast
of west coast of Eyre Peninsula to western
Kangaroo Island, and is characterised by an
ephemeral temperature inversion within the shelf
waters, south of Eyre Peninsula, during October
and November (Wenju et al. 1990). The inshore
coastal regions under the influence of result in
inshore temperatures of 11oC during the summer
months, to offshore sea surface temperatures, away
from the influence of the upwelling, of 18oC (Wenju
et al. 1990). The region from Point Sir Isaac (Coffin
Bay Peninsula) to Cape Borda (northwestern
Kangaroo Island) appears to be the major epicentre of
the coastal upwellings, and there appears to be a
relationship between the upwellings, and the pilchard
numbers in these areas (Ward & McLeay 1998).
There is also a potential link with the abundance of
other economic species (abalone, Southern Rock
Lobster) and also, local seabird, seal and sea lion
abundance in the region. Benthic biodiversity and
productivity (particularly for marine macroalgae
and benthic invertebrates) is also very high in this
region.
Offshore Islands
a subaerial bedrock basement, preserving a rich
history of Holocene sea-levels and evolution in
their beach and foredune ridges, mangrove stands
and samphire flats. St Peter Island also contains
mangroves, as well as a spectacular 4 km long spit
in lee of the island. Some of the islands also have
significant European heritage value.
"Geological Monuments"
There are 15 "Geological Monuments" identified by
the South Australian Museum and Geological
Society of Australia that are associated with the
coastline or offshore waters of the Eyre Coast
(further details are supplied in the relevant biounit):
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
Merdayerrah sandpatch
Clare Bay
Point Le Hunte (by Point Sinclair)
Laura Bay
Eyre Island
Point Brown
Point Collinson (northern Streaky Bay)
Acraman Creek
Smooth Pool headland, near Sceale Bay,
Westall Peninsula
Talia Caves: coastal landform.
Drummond Point
Coastal outcrops of old Precambrian rocks on
southern (and southeastern) Eyre Peninsula.
Whalers Way-Fishery Bay to Cape Carnot
Cape Carnot
Cape Catastrophe
Further details of these areas are supplied in the
relevant regional biounit descriptions below.
2
SIGNIFICANT
CULTURAL
HISTORICAL FEATURES
AND
The following description of Aboriginal and
European history along the Eyre Coast is
necessarily brief and selective, providing a focus
on coastal and maritime history. Only details of
Aboriginal historical and cultural sites that have
been published in the available literature are
described. Aboriginal sites, objects and remains
are protected under the South Australian
Aboriginal Heritage Act (1988), and a register of
such sites, objects and remains is kept with the
Aboriginal Heritage Branch of the South Australian
Department of Environment, Heritage and
Aboriginal Affairs.
In addition their ecological importance, the islands
between Cape Catastrophe and the islands of the
Nuyts Archipelago are also important geologically,
because they provide insight into the geology of the
adjacent shelf. Islands of particular significance
include, the Investigator Group of Islands
(particularly the Pearson Islands) which are true
granitic inselbergs, and the Eyre Islands (Little
Eyre and Eyre), which are the only islands without
Page 12
EYRE REGION
2.1 Aboriginal
Traditional uses still occur at Yalata (near Fowlers
Bay) and more recently, Yaralina (Murat Bay).
Although PALO has expressed interest in the joint
management of a number of cultural sites in Coffin
Bay and at Hill Bay, near Drummond Point.
History
The Aboriginal history of the Eyre Coast is complex
and difficult to summarise briefly. At the time of
early European settlement, however, there were two
dominant Aboriginal sociocultural systems; the
Banggala and the Gugada (Berndt 1985).
Prior to 1878, the Gugada people were occupying
country between Venus Bay and Point Brown, along
the coast and inland to the Gawler Ranges; but they
were not restricted to the area and frequently came
into Port Lincoln and Fowlers Bay.
Culturally, if not socially, they virtually
overwhelmed, especially the Wirangu, and were
certainly making inroads into both Banggala and
Nauo territories at the time of European settlement.
The Wirangu people occupied the northwestern side
of the Peninsula, along the coast from Fowlers Bay
to south of Streaky Bay (Tindale 1974). The
Wirganu, essentially not a Western Desert
population, were probably forced southward by
expanding Desert groups (Berndt 1985).
According to Tindale (1974), Banggala country
extended as far south as Franklin Harbour, then to
Tumby Bay and then into Port Lincoln with the
establishment of European settlement. He identified
two divisions in this group: the Nauo and the
Banggala.
The Nauo probably occupied the
southern Eyre Peninsula from Venus Bay, south to
Port Lincoln and west to Franklin Harbour. The
Nauo land of the dead was on islands in Spencer
Gulf, while the Banggala located theirs on islands to
the west, probably out from Coffin Bay (Angus
1847), implying considerable movement and
displacement of local groups must have taken place
prior to European contact. It is not known whether
the Nauo originally occupied the western area of the
peninsula or were forced in that direction by the
Banggala.
Cultural Sites
Sparse occupation and sites because of the arid
environment. All coastal sites along the Eyre Coast
are all surface sites with no stratigraphy - have
been eroded by natural processes. However, most
sites on the west coast are not been disturbed by
European activities. Sites of cultural significance
along the Eyre Coast generally decrease from north
to south, as human presence and activity increases.
As such, there exists a number of coastal sites in
the Fowler's Bay - Elliston region worthy of
consideration for listing on the Register of the
National Estate (A. Nicholson, pers. comm.).
These include, the site complex at Point Brown, the
middens at Acramen Creek, and the middens at
Corvisart Bay (Nicholson 1991). The region
encompassed within the Murat Bioregion
represents one of the most significant regions of
Aboriginal heritage along the whole of the Eyre
Coast (A. Nicholson pers.comm.).
The remoteness of the region has resulted in many
sites remaining completely undisturbed by European
activities. Nicholson (1991), in a survey of cultural
sites from Fowlers Bay to Elliston, identified the
following occupation sites as being particularly
significant:
−
−
−
Point Brown 4 (approximately 400-500 years
old): a recent occupation complex consisting of
middens and an artefact manufacturing site. To
be recommended for National Estate listing
(Nicholson pers.comm.).
Acraman Creek 4 (approximately 6,700 years
old): a discrete occupation site consisting of four
middens. To be recommended for National
Estate listing (Nicholson pers.comm.).
Corvisart Bay 3, Granites (approximately 67,000 years old): a discrete occupation site
consisting of three middens.
To be
recommended for National Estate listing
(Nicholson pers.comm.).
In addition to these outstanding sites a number of
other occupation sites of cultural significance have
also been identified by Nicholson (1991):
−
−
−
−
Tourville Bay 7, Nadir Landing: a discrete
occupation site: an artefact or stone scatter. One
of the ten largest occupation sites in the Eyre
Province.
Tourville Bay as a region is
considered to be of moderate Aboriginal
significance and sensitivity, however the rocky
coast within the bay is considered to be of high
sensitivity
and
moderate
significance
(Nicholson 1990).
Perlubie 2, near Eba Island: a discrete
occupation site 20 m from MHWM: an artefact
or stone scatter. One of the ten largest
occupation sites in the Eyre Province.
Corvisart 7, Yanerbie sandpatch: a discrete
occupation site consisting of cultural, animal
bones.
Venus Bay 7: an occupation site complex,
consisting of one midden and an artefact or
stone scatter.
Page 13
EYRE REGION
The region between Fowler's Bay and Streaky Bay is
also culturally significant for the dominance of
`natural' Aboriginal fishtraps in this region (Martin
1988). These fishtraps used modified natural features
such as rock platform reef formations, tidal pools and
shellgrit ridges.
None of these types of traps have been recorded
elsewhere along the west coast of Eyre Peninsula.
−
Natural Aboriginal fish traps have been found at
Rocky Point (1), Tourville Bay (2), Murat Bay
(10), Halfway Camp, in Murat Bay (1), Point
Dillon-Cape Missiessy (1), Smoky Bay (1), and
Eba Island (1) (Martin 1988).
−
`Constructed' Aboriginal fishtraps, consisting of
woven wooden traps, have been recorded at
Duckponds Creek, in Murat Bay (1) and on the
north coast of St Peter Island (1) (Martin
1988).
The Murat Bay Aquaculture Management Plan
(1991) reports the following areas of Aboriginal
significance in this region2:
−
The rocky coast of the Point James Zone has
Aboriginal sites of high sensitivity and
moderate significance, whilst the sandy coast
has Aboriginal sites considered to be of
moderate sensitivity and low significance
(Nicholson 1990).
−
The rocky coast occupied by Ceduna and
Thevenard probably had Aboriginal sites of
high sensitivity and moderate significance, but
unfortunately most of this area is now highly
developed and the sites disturbed (Nicholson
1990).
−
Aboriginal sites along Cape Beaufort are
considered to be of high sensitivity and
moderate significance (Nicholson 1990).
−
The rocky coast of the Waterwitch Aquaculture
Zone has Aboriginal sites of high sensitivity and
moderate significance; the sandy coast has sites
of high sensitivity and low significance. The
beach east of Wittlebee Point and the southern
part of Smoky Bay have sites of moderate
sensitivity and significance.
−
The rocky coast of the Wittlebee Zone has
Aboriginal sites of high sensitivity and moderate
significance.
−
In Laura Bay, sites of high sensitivity and
moderate significance occur on rocky coast,
while sites of moderate
significance in sandy areas.
sensitivity
and
2.2 European
Early Discoverers
The first explorer to touch the South Australian
coast was the Dutchman, Francors Thyssen in the
'Gulden Zeepard' in 1627. He sailed eastwards
across the Bight as far as the Nuyts group of
islands, but turned back because of the inhospitable
coast.
It was more than 150 years later when the
Frenchman D'Entrecasteaux sailed eastwards to the
Nuyts Archipelago and then to Van Diemen's Land.
The exploration and mapping of the coast of Eyre
Peninsula began with the Englishman Flinders and
his crew who arrived aboard the 'Investigator' at
Fowlers Bay on 28 January 1802.
He proceeded in an easterly direction charting the
outline of the Peninsula and naming features after
places in his native Lincolnshire, after supporters
of the voyage, and from the way the features
appeared to him (eg. Smoky Bay). He also named
islands after his crew, such as at Cape Catastrophe
where the Master of the 'Investigator' (Thistle), and
seven crewmen were drowned. Memory Cove was
so named to commemorate those lost.
Following the initial discoverers came whalers and
sealers, and before settlement had begun, there was a
thriving whaling, sealing and fishing industry. The
remains of early sealers' huts and whaling stations
may still be seen on some of the beaches and
offshore islands (Watts & Ling 1985). The South
Australian Company, in addition to its operations at
Encounter Bay on Fleurieu Peninsula, established
whaling stations on Thistle Island at the foot of
Spencer Gulf and at Sleaford Bay on the tip of Eyre
Peninsula (Colwell 1969).
Port Lincoln was founded in March of 1839, and
increased settlement and agriculture began on a
broader scale in the region.
2
"Sensitivity" refers to the quantity of sites in a particular region
:the more sites there are in a region, the more "sensitive" it is
thought to be. "Significance" refers to the quality or importance of
sites within a given region and is defined according to certain
criteria such as significance to the archaeological discipline or to
the Aboriginal community.
Page 14
EYRE REGION
Shipwrecks
Wrecks situated in State waters may be protected by
proclamation under the State legislation, ie. Historic
Shipwrecks Act 1981. As yet, no shipwrecks within
the State waters of southern Eyre Peninsula have
been declared historic (under the Historic Shipwrecks
Act 1981). However, three shipwrecks and some
whaler’s anchors older than 75 years are located in
Commonwealth waters and are automatically
protected under the Commonwealth legislation (ie.
Historic Shipwrecks Act 1976): the `Mary Ellis’
(which has been located); the `Amelia’ which is
located in Avoid Bay; the HMS `Investigator’ cutter
near Cape Catastrophe; and possibly one or two
whaler’s anchors in Fishery Bay.
Although there are no recorded historic shipwrecks
or relics for this section of coastline, it is likely that
they do exist. The absence of protected sites along
the Eyre coast is probably due to the lack of
research rather than a lack of significant sites (B.
Jeffery, State Heritage Branch, pers. comm.).
3
CURRENT CONSERVATION STATUS
OF THE EYRE COAST
Prior to 1996, only one, small Aquatic Reserve had
been declared in this region (ie. Point Labatt). This
reserve was established specifically for the
protection of a breeding colony of the rare
Australian Sea Lion and no public access to this
reserve is permitted. In 1996, the SA Government
declared South Australia’s first multiple-use Marine
Park, the Great Australian Bight Marine Park, at the
Head of the Bight, adjacent to the Nullarbor
National Park. The park comprises both, a Marine
Sanctuary (managed under the Fisheries Act), and
also, a National Park (managed under the National
Parks and Wildlife Act) and is the largest Marine
Protected Area in South Australia (168,300 ha),
comprising approximately 85% of the total area of
MPAs in SA. The park was established primarily to
protect critical nursery areas of the endangered
South Right Whale at the Head of the Bight, and
several breeding colonies of rare Australian Sea
Lions. `Netting closures' have also been declared in
the region, however these areas have generally not
been formally recognised as MPAs (see Ivanovici
1985, McNeill 1991).
Present MPAs in this region include:
−
Marine Reserves
Point Labatt Aquatic Reserve (230 ha)
−
Marine Parks
Great Australian Bight Marine Park (129o 132oE, 3 nautical miles offshore), comprising:
−
Marine Sanctuary
Great Australian Bight Marine Park Whale
Sanctuary (43,587 ha)
−
National Park
Great Australian Bight Marine National Park
(124,732 ha)
Netting Closures
−
−
−
−
−
−
−
Fowlers Bay
Denial and Smoky Bay
Streaky Bay
Baird Bay
Venus Bay
Waterloo Bay
Coffin Bay
Page 15
EYRE REGION – NULLARBOR BIOUNIT
I
MARINE BIOGEOGRAPHY AND CONSERVATION VALUES OF THE
NULLARBOR BIOUNIT
This biounit extends from Wilson Bluff on the border of Western Australia3, to the Head of Bight, and covers an
area of 842,642ha and a coastal distance of 209 km. It faces south into the Great Australian Bight.
(3 This is the geographical limit for the Eyre Peninsula Coast Protection District.)
No seagrass habitats have been recorded in the
region.
MARINE BIOGEOGRAPHY
1
OCEANOGRAPHY
Predominantly high wave energy associated with
the high cliff coastline. Moderating wave energy in
the Head of Bight.
2
GEOLOGY
AND
GEOMORPHOLOGY3
COASTAL
The first 30 km eastwards from the Western
Australian border consists of 90 m high Tertiary
Limestone cliffs and a large sand patch at
Merdayerrah. Here, sediments deposited at the
base of the Nullarbor Cliffs during the Pleistocene
have lithified, forming 400-1,000 m wide dune
calcarenite ramps.
These have been partly
transgressed by Holocene dunes which have also
overtopped the 90 m high Nullarbor Cliffs in
places. The existing transgression is likely to be
due to past episodes of shoreline regression, frontal
dune instability and the low rainfall. The next 179
km from the Merdayerrah Sandpatch eastward
consists of an unbroken line of towering limestone
cliffs until the Head of the Bight. There are small
gradients in cliff height and changes in orientation
which provide the only variation in an otherwise
uniform coastal geomorphology. Inland of the cliff
line, the plain extends as a near horizontal surface.
3
BIOLOGY
Major Inshore Habitats
−
Major intertidal habitats in the region include
mostly limestone cliffs, and some sandy
beaches.
−
Of the total inshore subtidal habitats mapped
in the biounit (15,744ha), sandy bottoms
comprise 11,836 ha (75.2%), and limestone
reefs comprise 3,908 ha (24.8%).
3
The coastal nearshore marine habitats of this
biounit comprise mostly sand out to at least 2-3km,
interspersed with small narrow patches of low
profile limestone reef (Edyvane & Baker 1996,
Edyvane & Andrews 1996). East of the Head of
Bight (131o30’E) to the Western Australian border
(132o00’E), the nearshore area is characterised
mainly by sandy habitat (69%), interspersed with
patches of limestone reef which comprise
approximately 31% of the total nearshore habitat
area (Edyvane & Baker 1996, Edyvane & Andrews
1996). Within this region, the major nearshore
reefal habitats appear to occur east of the Dog
Fence (131o40’ E), with reefal habitats comprising
approximately 26% of the total habitat area,
compared with 5% of the total area in the region
west of the Dog Fence.
Major Benthic Communities
•
Macroalgal
−
The marine benthic habitats of this region
within the Great Australian Bight has been the
subject of few studies. Biological surveys
conducted by researchers from SARDI in June
1994 indicate subtidal benthic communities
assemblages in the region are typical of warm
to cool temperate waters, and high swell wave
conditions. On the rocky limestone reefs
within the Great Australian Bight Marine
Park, subtidal macroalgal communities are
dominated by the kelp, Ecklonia radiata and
the fucoid Scytothalia dorycarpa (Edyvane &
Andrews 1996), and articulated (eg. Amphiroa
sp.) and encrusting coralline algae.
Of
particular interest is the presence of a
suspected relic tropical assemblage in the
macroflora, indicated by the presence of an
undescribed fucoid, Sargassum spp.
No
seagrass communities have been recorded
within this biounit.
From Eyre Coast Protection District Study Report.
Page 16
EYRE REGION – NULLARBOR BIOUNIT
& Burnell unpubl.data, cited in Burnell &
Bryden in press). Recent studies at the Head
of Bight have confirmed the size and density
of the aggregation, with a total of 45 whales
counted within the site on one day (ie. August
1994), and a total of 101 individual whales
(based on photo-identifications) recorded
during the winter of 1994. The duration of
coastal residence for Southern Right Whales at
the Head of Bight can potentially last up to
162 days, with whales recorded arriving as
early as 10 May and leaving as late as 18 June
in 1993, although on average the season
extends for approximately 120 days (Burnell
& Bryden in press).
Coastal and Offshore Islands (or Reefs)
−
Nil.
Rivers and Estuaries
−
Nil.
MARINE CONSERVATION VALUES
1
SIGNIFICANT BIOLOGICAL AND
PHYSICAL FEATURES
−
Southern Right Whales are presently
considered both `endangered' (under the
Commonwealth Endangered Species Act
1992) and `vulnerable to extinction' (by the
World Conservation Union, and the
International Union for the Conservation of
Nature). Recently, the species has been
proposed as `vulnerable’ under the Cetacean
Action Plan for Australian Cetaceans
(Bannister et al. in press). Estimates currently
put the world population of Southern Right
Whales at around 1500 to 3,000 individuals,
with
an
Australian
population
of
approximately 600-800 (Bannister et al. in
press). Major populations are also recorded
off South Africa and South America. The
populations off South Australia and at the
Head of Bight have shown no apparent
increase (Ling & Needham 1991, Bannister et
al. in press). While the species is presently
recovering, the suspected very low diversity of
the gene pool in the population (after being
hunted to near extinction), has made the
species particularly vulnerable to catastrophic
collapses, such as from the effects of human
activities or environmental changes.
−
The Great Australian Bight Marine Park
protects the largest and densest breeding
aggregation of Southern Right Whales in
Australia, and one of the two major breeding
and calving areas for this species in the world.
As such, it has been identified as a major step
in assisting the global recovery of this
endangered and vulnerable species (see
Southern Right Whale Recovery Plan,
National Cetacean Action Plan).
1.1 Biological
-
−
The Great Australian Bight region is
becoming recognised world-wide as a
significant critical seasonal habitat for
populations of the endangered Southern Right
Whale (Eubalaena australis). Within the
Great Australian Bight region, the breeding
and calving aggregation or nursery area at the
Head of Bight is the largest, densest and most
consistent
aggregation
in
Australia
(representing one of the two major breeding
and calving areas for this species in the
world). Every year, between the months of
May and November, approximately 50-60
whales visit the Head of Bight region to calve,
nurse their young and breed. The coastline
from the Head of Bight to the West Australian
border is used consistently, with many
lactating females following the coastline west
for varying distances during the latter part of
their coastal residence season before turning
south (Burnell, pers.comm.). Currently,
breeding and calving aggregations are
restricted to western South Australia, and
Western Australia along the shores of the
Great Australian Bight to Cape Leeuwin, with
peak abundances in areas such as the Head of
Great Australian Bight and Israelite Bay.
Along the western and central southern coast
of Australia there appears to be some
preference by calving females for shallow
north-east trending bays over sandy bottoms,
with animals occurring in a narrow band,
generally no more than 1 km from the
shoreline (Bannister et al. 1996).
Over recent years this aggregation of Southern
Right Whales at the Head of Bight has been
the largest, densest and most consistent
aggregation and nursery area in Australia,
producing approximately one-third of the
observed total number of right whale born in
Australian coastal waters each year (Bannister
Page 17
EYRE REGION – NULLARBOR BIOUNIT
−
pups (under 12 months) were recorded, while
in 1995, 90 pups (under 6 months of age),
were recorded, of which 44 were still in
lanugo (Dennis & Shaughnessy 1996).
Breeding events were recorded at one colony
over three seasons and were consistent with
an eighteen month breeding cycle. At one
colony the number of pups recorded from the
cliff-edge in August 1994 was doubled when
a subsequent count was made by entering the
colony.
Blue,
Sperm,
Minke
(Balaenoptera
acutorostrata) and Humpback Whales are
reasonably commonly sighted, aswell as
stranding around the Great Australian Bight.
Possibly resident cetaceans are the Beaked
Whale, Killer Whales (Orcinus orca) and
Risso’s
Dolphin
(Grampus
griseus).
Individuals of tropical species such as Bryde’s
Whale (Balaenoptera edeni) are occassionally
seen in South Australian waters, and it has
been suggested that they have travelled on the
warm Leeuwin Current (Kemper & Ling
1991).
Bottlenose Dolphins (Tursiops
truncatus) have been seen on many occasions
playing amongst Southern Right Whale
groups (Ling & Needham 1988, Bannister
1993).
−
Two species of seals or pinnipeds are found in
the Great Australian Bight region: the rare
Australian Sea Lion (Neophoca cinerea) and
the New Zealand Fur Seal (Arctocephalos
forsteri) (Edyvane & Andrews 1995). In
particular, the region contains many small
breeding colonies of the Australian Sea Lion
and as such, is becoming increasingly
recognised as area of global conservation
significance for this species. The Australian
populations of the New Zealand Fur Seal are
limited in their distribution to the Great
Australian Bight, extending from the islands
of Recherche Archipelago (WA), eastwards to
Kangaroo Island (SA).
−
Recent systematic surveys of potential seal
haul-out sites along the coastline of the Great
Australian Bight, from Twin Rocks to
Wilson’s Bluff (ie. a coastal distance of 206
km) have identified a total of approximately
280 Australian sea lions and 12 New Zealand
fur seals (Dennis & Shaughnessy 1996). In
1994, a total of 289 Australian sea lions were
recorded at 23 sites widely dispersed at the
base of the Bunda Cliffs, while in 1995, a total
of 284 sea lions were recorded at 10 sites.
(Dennis & Shaughnessy 1996). Of these sites,
9 occurred in South Australia, and 1 occurred
in Western Australia (2km west of Twilight
Cove). Overall, a total of 10 breeding sites
and 14 haul out sites were identified for the
region. A total of 12 New Zealand Fur Seals
were recorded for the same area of coast.
Australian sea lions were found
hauled-out on perched platforms
formed by collapsed sections of the
cliff at various levels above the sea.
In 1994, a large colony of 37 sea lions
were recorded in a deep cave accessed
from the sea. In 1994 a total of 86
−
By extrapolating from the number of sea lion
pups found in the 1994 survey, the population
of the Great Australian Bight region in South
Australia has been estimated at between 613
and 744, which represents approximately
9.3% of the South Australian population or
6.6% of the total world population for this
species (Dennis & Shaughnessy 1996). The
significance of the populations of Australian
sea lions in the Great calves Australian Bight
is further increased because it is very likely
that the populations were never commercially
harvested - like many other populations along
the southern coasts and islands of Australia
last century. Generally, to the point of
extinction. This is principally because of the
isolation and general inaccessibility of the
Great Australian Bight coast, both, from land
and sea. Thus the populations have remained
intact, providing probably one of the greatest
sources of genetic diversity for this species in
the world, and also, a very important genetic
and geographic bridging population between
the South Australian and Western Australian
sea lion populations (Dennis & Shaughnessy
1996).
The warm waters of the Great Australian
Bight are also characterised by a unique
`tropical' or Indo-Pacific element both, in the
demersal and pelagic fauna (Maxwell &
Cresswell 1981).
Among the benthic
invertebrate fauna, many of the echinoderm
species recorded from South Australia
originate from the Indo-Pacific region
(Maxwell & Cresswell 1981). For instance,
some 20 of the 84 species of hydroid recorded
from South Australia have their principal
distribution in the warm waters of the IndoMalay region. Other echinoderms of IndoPacific origin include the Basket Star (Euryale
aspera), and the holothurians, Pentacta
anceps
and
Pentacta
quadrangularis
(Maxwell & Cresswell 1981).
Page 18
EYRE REGION – NULLARBOR BIOUNIT
−
The warm water of the Leeuwin Current is
also responsible for the dispersal of pelagic
marine organisms from waters north-west of
Australia to the southern seaboard (Maxwell
& Cresswell 1981). Tropical pelagic species,
such as the Oriental Bonito and the Southern
Bluefin Tuna move with the Leeuwin Current
in their migration from the spawning grounds
in the Java Sea. These same warm equatorial
waters are also thought to be responsible for
the significant tropical element in the phytoand zooplankton of the Great Australian Bight
(Markina 1976) and the suspected relic
tropical assemblage in the marine flora (ie.
Sargassum spp.).
−
The influence of the Leeuwin Current is also
reflected in the Holocene sediments of the
Eucla Shelf, which are characterised by a lack
of bryozoans, and an abundance of coralline
algae and the large foraminifer, Marginopora
(James et al. 1994).
−
Very little information on seabirds has been
collected in the Great Australian Bight,
particularly feeding and nesting aggregations.
While breeding colonies of Little Penguins
(Eudytula minor) are known to occur at the
base of the Nullarbor Cliffs in the region,
many seabird species, such as Short-tailed
Shearwater (Puffinus tunuirostris) and Whitefaced Storm Petrel (Pelangodroma marina),
probably feed in the area and/or breed wholly
or largely on the offshore islands of the Great
Australian Bight (Copley 1996).
Other
species which may frequent the Great
Australian Bight include the Black-faced
Shag, Eastern Reef Egret, Cape Barren Goose,
White-bellied Sea-eagle, Sooty Oystercatcher,
Pacific Gull, Fairy Tern, Crested Tern, Rock
Parrot, and the Fleshy-footed Shearwater
(Smith Island) (Eckert et al. 1985). Nonbreeding migratory seabirds such as
Albatrosses, Petrels and Prions are known to
frequent the coastal and shelf regions of the
Great Australian Bight, but to an unknown
degree (Copley 1996). Other species breed on
more protected, inshore islands along the
coast.
1.2 Physical
−
The Leeuwin Current: a major eastern
boundary current system off the west coast of
Australia. This warm, low salinity current
originates from the tropical Indian Ocean and
during winter from May to SeptemberOctober, flows south along the shelf break of
the west coast, along the southern coast of
Australia, to the eastern Great Australian
Bight (to approximately 130oE).
−
For coastal and offshore fisheries, the
Leeuwin Current is intimately linked to the
population dynamics of many of Western
Australia's and to a lesser extent, South
Australia's, commercially important species
(Lenanton et al. 1991). As such, the life
history characteristics, such as spawning,
migration, recruitment and feeding patterns,
and ultimately the overall production, of many
species along the western and southern
seaboard of Australia have evolved under the
influence of such a current system. Almost all
of the major economically important fish
stocks off the western and southern coasts of
Western Australia are influenced to some
extent by the Leeuwin Current (Lenanton et
al. 1991).
−
Some pelagic species use the Leeuwin Current
to disperse from the north-western waters of
Australia to the southern seaboard of
Australia. For instance, the Southern Bluefin
Tuna (Thunnus maccoyii) spawns in the Java
Sea and migrates southward along the western
Australian coastline and eastward along the
southern coast of Australia. It is an important
commercial species and its distribution and
abundance is influenced by the seasonality,
strength and timing of the Leeuwin Current.
Other commercial pelagic fish whose
distribution and abundance is affected by the
Leeuwin Current include, Mackerel (Scomber
australasicus), Horse Mackerel (Trachurus
declivis),
Australian
Salmon
(Arripis
truttaceus), and Australian Herring (Arripis
georgianus). Southern Bluefin Tuna and the
latter two species are particularly important
fisheries in South Australian waters (Cappo
1987, Jones 1991).
Page 19
EYRE REGION – NULLARBOR BIOUNIT
−
In South Australia, the Leeuwin Current also
brings warm waters to the Head of the Great
Australian Bight.
Since cetaceans are
generally born with little blubber, this is
thought to explain the existence of several
critical breeding areas for the endangered
Southern Right Whale in this region. The
warm Leeuwin current has also been
suggested as a mechanism for bringing
occasional individuals of tropical species such
as Bryde's Whale into South Australian waters
(Kemper & Ling 1991).
−
Merdayerrah sandpatch: Pleistocene wave cut
platforms which indicate two previous sealevel events.
The site is a recognised
"geological monument" and is considered
important for research into Quaternary
sedimentation and sea-level history.
2
OTHER VALUES
2.1 Commercial Fisheries
Southern Rock Lobster
Most of the present fishing activity for Southern
Rock Lobster (Jasus edwardsii) is confined to the
eastern sector of this biounit, along rocky reefs east
of Twin Rocks (ie. Fishing Zone 3, see Wahgunyah
Biounit). While fishing activity has increased
within this area in recent years, particularly in
1993/94, fishing activity has traditionally been
minimal and opportunistic, with effort and catch
rates representing a small proportion of the total
effort and total catch of Southern Rock Lobster for
the Northern Zone.
Abalone
No Blacklip Abalone or Greenlip Abalone is
presently commercially harvested within this
biounit. Based on the area of reefal habitat
available for reef-associated species, existing and
potential demersal fishing grounds for species, such
as Blacklip Abalone and Southern Rock Lobster
are likely to be limited within the Nullarbor Cliffs
Biounit (Edyvane & Andrews 1996).
Marine Scale Fishery
During 1995/96 and 1996/97, 7 and 9 commercial
licence holders, respectively (made up of Marine
Scalefish, Restricted Marine Scalefish and
Northern Zone Rock Lobster licence categories)
took marine scalefish from the waters between the
Western Australian-South Australian border and
the Head of Bight (ie. Fishing Zones 1 and 2).
License holders expended approximately 51 and 50
boat days effort fishing these waters during
1995/96 and 1996/97, respectively.
Large mesh gill netting (>15cm mesh) was by far
the most important method of capture, followed by
handlines and rod and line (Jones 1991). The main
species taken in inshore (<50m) waters were
Gummy (Mustellus antarcticus) and Bronze
Whaler (Charcharinus brachyurus) sharks, Sweep
(Scorpus aquepinnis), Mulloway (Argyrosomus
hololepidotus) and Australian Salmon (Arripis
truttaceus), and in offshore waters, School Shark
(Galeorhinus galeus), Ocean Leatherjackets
(Nelusetta ayraudi) and Deep Sea Trevalla
(Hyperoglyphe antartica) (Jones 1991).
This
fishery also includes such species as Pilchards,
Whiting, Tommy Ruff, and Redfish.
Records indicate that pregnant School Sharks move
from south-eastern Australia to the Great
Australian Bight for the period of gestation, and
then return eastwards to give birth (Walker et al.
1989).
The marine scalefish catch for this region (ie.
Fishing Zones 1 and 2), represented less than 70
tonnes in 1995/96 and 34 tonnes 1996/97(or 0.33%
and 0.24% of the total catch for the marine
scalefish fishery in South Australian waters).
Increases in shark and marine scalefish catches in
recent years (ie. since 1991/92) with the Great
Australian Bight region, are not apparent. The
majority of this catch (90%+) is made up of Shark.
Large mesh gill netting (>15cm) was by far the
most important method of capture (Jones 1991).
Extensive pilchard fisheries occur in bays to the
west of the Great Australian Bight (Esperance,
Albany, WA), whilst in SA, operations target areas
east of the Bight. In 1992/93, the total allowable
catch (TAC) for the pilchard fishery (3,450 tonnes)
constituted half of the SA’s commercial marine
scale fishery.
Page 20
EYRE REGION – NULLARBOR BIOUNIT
Deep Sea Trawl Fishery
The Great Australian Bight trawl fishery is a
Commonwealth managed fishery which extends
from Kangaroo island off South Australia, to Cape
Leeuwin in Western Australia, a distance of over 2
000 km. The southern boundary of the Great
Australian Bight Trawl Fishery is the edge of the
Australian Fishing Zone (AFZ) which extends to
200 nautical miles offshore.
The northern
boundary (31.52oS) mostly follows the 200m depth
contour about 20-90 nautical miles offshore.
Fishing activity in the Great Australian Bight Trawl
fishery is currently confined to a fairly narrow
margin off the continental shelf and slope, in
depths of less than 1 200 m, mostly within the 100200 m depth zone (BRS 1993).
Data from the Great Australian Bight Trawl
Fishery Logbook database indicate that species
caught at depths less than 200m (ie. the continental
shelf) comprise mostly Deepwater Flathead
(Neoplatycephalus conatus) and Bight Redfish
(Centroberyx gerrardi), while at depths greater
than 200m (ie. the continental slope), Orange
Roughy and various Oreo Dories (family
Oreosomatidae) are the main species. The slope
fishery has contacted in recent years and in 1994,
yielded the lowest catch on record (BRS 1994).
Bight (Jones 1991). Prior to this, effort was more
evenly spread throughout the waters of the Great
Australian Bight. The reason for the contraction of
the fishing area has been output controls in the
fishery through quota restrictions (Jones 1991).
This fishery operates outside the limits of the South
Australian jurisdictional waters (ie. seaward of
3nm). With the shift away from longline fishing to
purse seining, most fish are now taken south, below
32o00’S and east of the Great Australian Bight.
Prior to 1990/91, catches in this region varied from
less than 1% to 18% of the annual South Australian
catch - with the vast majority of the catch being
taken west of 130o55’E.
2.2 Mariculture
There are no aquaculture activities in this region at
present. The Far West Aquaculture Management
Plan (Ashman 1996) has recommended no
aquaculture development within this region:
Nullarbor Policy Area
−
This fishery is outside State waters (ie. 3nm).
Southern Bluefin Tuna
The Southern Bluefin Tuna (Thunnas maccoyii)
fishery is a Commonwealth managed fishery.
Southern Bluefin Tuna spawn between September
to March, in the warm waters of the Indian Ocean,
south of Indonesia. After spawning the tuna move
south along the western seaboard of Australia, and
easterly along the south coast of the Australian
continent, where juvenile fish of 1 to 4 years of age
school seasonally in the surface waters off southern
Australia. Southern Bluefin Tuna usually become
available to the Western Australian fishery at
approximately 1-2 years of age, and at
approximately 2 years of age for the South
Australian fishery. The fish are generally fished by
Japanese longliners when approximately 4 years of
age.
Southern Bluefin Tuna mature at
approximately 8 years of age and may live as long
as 40 years (BRS 1995). Young tuna tend to stay
in relatively shallow waters associated with coasts
and continental shelves. However, once they reach
maturity, they move to deeper oceanic waters and
live a pelagic existence. Because of their long
exposure to fishing activity prior to spawning, the
species is highly vulnerable to overfishing, and
then slow to recover.
Nullarbor Policy Area (all state jurisdictional
waters from the WA border, east to Point
Fowler) – zoned for protection of conservation
and wilderness values and existing fisheries
use. Licenses will not be considered for
aquaculture development in this zone.
2.3 Recreation and Tourism
Fishing
−
Great Australian Bight: shoreline fishing.
Major species: Australian Salmon and
Mulloway. Average catch rates for Australian
Salmon in this area in 1986/87 were the
highest of any area in the State.
Tourism
−
There is an increasing demand for `whale
watching' tours to the Head of the Bight.
Tourists view the Southern Right Whales
during May to November from the edge of the
cliffs.
−
The coastline from the West Australian border
to the Head of Bight has many lookouts that
take advantage of the spectacular views.
In recent years an active purse seine and pole
fishery for this species has been confined to the
South Australian sector of the Great Australian
Page 21
EYRE REGION – NULLARBOR BIOUNIT
2.4 Scientific Research and Education
−
Researchers from the South Australian
Museum and University of Sydney conduct
regular surveys of Southern Right Whales in
the Great Australian Bight region.
−
In recent years, scientific research at the Head
of Bight has greatly enhanced our
understanding of the reproductive biology and
behaviour of Southern Right Whales (see
Burnell & Bryden in press). The area at the
Head of Bight represents one of the few areas
in the world where the breeding and general
behaviour of the Southern Right Whales can
be observed closely by researchers (and the
public). The proximity of the whales to shore
and the unique cliff-top views represents one
of the best areas in the world where the
breeding, calving and general behaviour of
Southern Right Whales can be observed and
studied by scientific researchers. Because of
the absence of human interference in the area,
these scientific studies are highly important in
revealing the `natural' behaviour patterns of
the whales. For the same reason, the area also
affords some of best whale-watching views in
the world.
−
Agriculture/Industry
−
−
−
Nullarbor National Park (588,300 ha).
−
The Nullarbor National Park protects part of
the world's largest semi-arid karst (limestone)
landscapes. The park encompasses 593 000
ha and is a vast area of low open woodland;
the treeless karst plain comprising a portion of
the park.
The principal vegetation
communities consist of mallee and dry land
tea-tree, with an area of saltbush and bluebush
communities. There is no management plan in
place for this area and at present, no
management planning process has being
undertaken.
Yalata Aboriginal Land Lease (456,000 ha),
adjacent to the Head of Bight.
2.6 Significant Cultural and Historical Features
Aboriginal
−
Yalata Aboriginal Land. The Yalata
Aboriginal Land Lease is held in trust for the
Yalata Council by the Aboriginal Lands Trust
of South Australia. The Yalata lands cover a
total of 456,000 ha stretching from Coorabie
in the east to the Head of Bight in the west.
This portion of land abuts the Great Australian
Bight Marine Park immediately adjacent to the
critical breeding and calving areas at the Head
of Bight.
European
2.5 Adjacent Land Use
•
Urban Centres
None.
Other Uses
Fisheries research in this area includes, regular
catch and effort monitoring of the major State
and Commonwealth commercial fisheries in
the region and also, oceanographic research in
the Head of the Bight.
National and Conservation Parks
Apart form tracks and roads, there is no
development along this biounit. Spur roads
from the Eyre Highway provide access to a
number of scenic points. Tracks parallel to
the coast enable 4WD vehicles to reach most
other parts of the biounit.
−
None.
3
CURRENT CONSERVATION STATUS
OF THE NULLARBOR BIOUNIT
−
Marine Parks
Great Australian Bight Marine Park (129o 132oE, 3 nautical miles offshore), comprising:
−
Marine Sanctuary
Great Australian Bight Marine Park Whale
Sanctuary (43,587 ha)
National Park
−
Great Australian Bight Marine National Park
(124,732 ha)
Page 22
EYRE REGION – NULLARBOR BIOUNIT
4
AREAS OF HIGH CONSERVATION
VALUE IN THE NULLARBOR BIOUNIT
Great Australian Bight (offshore)
−
Prime
IUCN
Conservation
Values:
biodiversity,
rare
and
endangered
species/habitats, ecosystem protection (IUCN
Category II). IUCN Identification Criteria:
naturalness (not subjected to human induced
change),
biogeographic
(distinct
biogeographic/oceanographic
region),
ecological
(deepwater
bryozoan-sponge
communities, Leeuwin Current contributes to
essential ecological processes, deepwater
canyons), economic (shark and deepwater
flathead breeding areas, deep water), social,
international significance (global importance for
marine mammals, cetaceans, White Shark,
squid), practicality (compatibility-adjacent to
Great Australian Bight Marine Park–State
waters ).
Page 23
EYRE REGION – WAHGUNYAH BIOUNIT
II
MARINE BIOGEOGRAPHY AND CONSERVATION VALUES OF THE
WAHGUNYAH BIOUNIT
This biounit extends from the Head of Bight to Cape Adieu and covers an area of 195,381ha and a coastal
distance of 122 km. It faces southwest into the Great Australian Bight.
MARINE BIOGEOGRAPHY
1
OCEANOGRAPHY
Moderate to high wave energy.
2
GEOLOGY AND COASTAL
GEOMORPHOLOGY4
Apart from the Nullarbor Cliffs, the orientation,
form and evolution of the Holocene shoreline is
generally uniform, consisting of Holocene barrier
deposits, usually backed by moderate to extensive
episodic transgressive barriers. The Yalata sand
dunes at the Head of the Bight extend more than
7km inland and form the largest active
transgressive dune system in the biounit. Low
cliffs or shore platforms and reefs consisting of
Pleistocene dune calcarenite outcrop extensively
along the coast.
Nuyts Reef consists of three main clusters of rocks
which form a roughly triangular pattern, the
northern part of which is an elongate rocky outcrop
of crystalline basement.
3
BIOLOGY
Major Inshore Habitats
−
Major intertidal habitats in the region include
mostly sandy beaches, and some limestone
rocky shores.
−
Of the total inshore subtidal habitats mapped
in the biounit (29,693ha), sandy habitats
comprise 27,971 ha (94.5%), and limestone
reefs comprise 1,722 ha (5.8%). No seagrass
habitats have been recorded in this region.
4
The coastal nearshore marine habitats of this
biounit comprise mostly sand out to at least 2-3km,
interspersed with small narrow patches of low
profile limestone reef (Edyvane & Baker 1996,
Edyvane & Andrews 1996). West of the Head of
Bight (130o30’E to 129o00’E), reefal habitat is
mainly confined to within 0-100m of the coastal
cliffs of the Nullarbor, the rest of the habitat,
seaward of the coastal reef, comprising sand, out to
2-3km. However, narrow sections of limestone
reef, ie. irregular patch reefs, do occur further
offshore in the western Nullarbor region, near the
Merdayerrah Sandpatch (129o30’E to 129o00’
East), but sandy habitat is by far the dominant
habitat.
Major Benthic Communities
•
Macroalgal
−
The marine benthic habitats of this region
within the Great Australian Bight has been the
subject of few studies. Biological surveys
conducted by researchers from SARDI in June
1994 indicate subtidal benthic communities
assemblages in the region are typical of warm
to cool temperate waters, and high swell wave
conditions. On the rocky reefs within the
Great Australian Bight Marine Park, subtidal
macroalgal communities are dominated by the
kelp, Ecklonia radiata and the fucoid
Scytothalia dorycarpa (Edyvane & Andrews
1996), and articulated (eg. Amphiroa sp.) and
encrusting coralline algae.
Of particular
interest is the presence of a suspected relic
tropical assemblage in the macroflora,
indicated by the presence of an undescribed
fucoid, Sargassum spp.
No seagrass
communities have been recorded within this
biounit.
From Eyre Coast Protection District Study Report.
Page 24
EYRE REGION – WAHGUNYAH BIOUNIT
Coastal and Offshore Islands (or Reefs)
2
−
D'Entrecasteaux Reef.
2.1 Commercial Fisheries
−
Yatala Reef.
−
Rivers and Estuaries
None.
MARINE CONSERVATION VALUES
1
SIGNIFICANT BIOLOGICAL AND
PHYSICAL FEATURES
1.1 Biological
−
Critical breeding and calving area for the
Southern Right Whale (Eubalaena australis):
Head of the Bight, Twilight Cove and
Merdayerrah (see Section 1.1, Nullarbor
Biounit). Whales are also often seen moving
along the coast towards the Head of Bight.
−
The Great Australian Bight region is best
known for its large cetaceans (see Section 1.1,
Nullarbor Biounit).
−
Tropical element in the fauna and flora of the
Great Australian Bight (see Section 1.1,
Nullarbor Biounit).
−
D'Entrecasteaux Reef is a haul out site for
Australian Sea Lions. A total of 20 sea lions
were recorded on this reef in 1977 (Robinson
& Dennis 1988).
1.2 Physical
−
The Leeuwin Current: see under Nullarbor
Biounit (see Section 1.1, Nullarbor Biounit).
−
The Yalata sand dunes at the Head of the
Bight extend more than 7 km inland and form
the largest active transgression dune system
along the Eyre Coast.
OTHER VALUES
Southern Rock Lobster
Most of the present fishing activity for Southern
Rock Lobster (Jasus edwardsii) in this region is
confined to the rocky reefs east of Twin Rocks (ie.
Fishing Zone 3). While fishing activity has
increased within this area in recent years,
particularly in 1993/94, fishing activity has
traditionally been minimal and opportunistic, with
effort and catch rates representing a small
proportion of the total effort and total catch of
Southern Rock Lobster for the Northern Zone.
In 1995/96 and 1996/97 a total of 7 and 6 licensed
operators fished in this area (ie. Fishing Zone 3),
catching approximately 21,138 and 6,756 kg of
lobsters, respectively (or 0.41% and 0.13% of the
total catch for Southern Rock Lobster in South
Australian waters).
Abalone
Limited Blacklip Abalone and Greenlip Abalone is
presently commercially harvested within this
biounit (i.e. MapCode 1D, D’Entrecasteaux Reef
region), but due to the confidentiality constraints
these figures are not available.
Based on the area of reefal habitat available for
reef-associated species, existing and potential
demersal fishing grounds for species, such as
Blacklip Abalone and Southern Rock Lobster are
likely to be limited within the Wahgunyah Biounit
(Edyvane & Andrews 1996).
Marine Scalefish Fisheries
The same commercial fin fisheries operate in this
biounit as for the Nullarbor Biounit. During
1995/96 and 1996/97, 7 commercial licence holders
(made up of Marine Scalefish, Restricted Marine
Scalefish and Northern Zone Rock Lobster licence
categories) took marine scalefish from the waters
between the Head of Bight and west of Cape Adieu
(ie. Fishing Zone 3).
Page 25
EYRE REGION – WAHGUNYAH BIOUNIT
License holders expended approximately 75 and 24
boat days effort fishing these waters during
1995/96 and 1996/97, respectively.
The marine scalefish catch for this region (ie.
Fishing Zone 3), represented 53,263 kg in 1995/96
and 16,209 kg in 1996/97(or 0.51% and 0.16% of
the total catch for the marine scalefish fishery in
South Australian waters). Increases in shark and
marine scalefish catches in recent years (ie. since
1991/92) with the Great Australian Bight region,
are not apparent. The majority of this catch (90%+)
is made up of Shark. Large mesh gill netting
(>15cm) was by far the most important method of
capture (Jones 1991).
2.5 Adjacent Land Use
National and Conservation Parks
−
2.2 Mariculture
There are no aquaculture activities in this region at
present. The Far West Aquaculture Management
Plan (Ashman 1996) has recommended no
aquaculture development within this region:
Nullarbor Policy Area
−
Nullarbor Policy Area (all state jurisdictional
waters from the WA border, east to Point
Fowler) – zoned for protection of conservation
and wilderness values and existing fisheries
use. Licenses will not be considered for
aquaculture development in this zone.
Agriculture/Industry
Apart form tracks and roads, there is no
development along this biounit. Spur roads from
the Eyre Highway provide access to a number of
scenic points. Tracks parallel to the coast enable
4WD's to reach most other parts of the biounit.
Urban Centres
−
2.3 Recreation and Tourism
Fishing
−
The same recreational fisheries operate in this
biounit as for the Nullarbor Biounit.
There is an increasing demand for `whale
watching' tours to the Head of Bight. Tourists
view the Southern Right Whales during May
to November from the edge of the cliffs.
2.4 Scientific Research and Education
−
Researchers from the South Australian
Museum and University of Sydney, conduct
regular surveys of Southern Right Whales in
the Great Australian Bight region (see Section
2.4, Nullarbor Biounit).
−
Fisheries research in this area includes, regular
catch and effort monitoring of the major
commercial fisheries in the region and also,
oceanographic research in the Head of the
Bight.
None.
Other Uses
−
Yalata Aboriginal Land, adjacent to the Head
of Bight.
2.6 Significant Cultural and Historical Features
Tourism
−
Wahgunyah Conservation Reserve (38,280
ha). Very little resource information is
available on this section of the land abutting
the eastern end of the Marine Park. The
Wahgunyah
Conservation
Reserve
is
designated a Conservation Reserve under the
Crown Lands Act. The area is presently
managed by the regional South Australian
National Parks and Wildlife office of the
Department of Environment and Natural
Resources (DENR). There is no management
plan in place for this area and at present, no
management planning process has being
undertaken.
Aboriginal
−
Yalata Aboriginal Land.
European
•
Shipwrecks
−
Little is known of shipwrecks on the west
coast of South Australia. There are records of
3 shipwrecks in this region. Only one is older
than 75 years and is a vessel of unknown
description recorded as being east of Twin
Rocks in Edward John Eyre’s journal on 4
March 1841.
Page 26
EYRE REGION – WAHGUNYAH BIOUNIT
3
−
CURRENT CONSERVATION STATUS
OF THE WAHGUNYAH BIOUNIT
Marine Reserves
None
−
Marine Parks
Great Australian Bight Marine Park (129o 132oE, 3 nautical miles offshore), comprising:
−
Marine Sanctuary
Great Australian Bight Marine Park Whale
Sanctuary (43,587 ha)
−
National Park
Great Australian Bight Marine National Park
(124,732 ha)
−
4
Netting Closures
None
AREAS OF HIGH CONSERVATION
VALUE IN THE WAHGUNYAH
BIOUNIT
Great Australian Bight (offshore)
−
Prime
IUCN
Conservation
Values:
biodiversity,
rare
and
endangered
species/habitats, ecosystem protection (IUCN
Category II). IUCN Identification Criteria:
naturalness (not subjected to human induced
change),
biogeographic
(distinct
biogeographic/oceanographic
region),
ecological
(deepwater
bryozoan-sponge
communities, Leeuwin Current contributes to
essential ecological processes, deepwater
canyons), economic (shark and deepwater
flathead breeding areas, deep water), social,
international significance (global importance
for marine mammals, cetaceans, White Shark,
squid), practicality (compatibility-adjacent to
Great Australian Bight Marine Park–State
waters ).
Page 27
EYRE REGION – FOWLERS BIOUNIT
III
MARINE BIOGEOGRAPHY AND CONSERVATION VALUES OF THE
FOWLERS BIOUNIT
This biounit extends from Cape Adieu to Point James, and covers an area of 146,486ha.
southwesterly direction into the Great Australian Bight.
MARINE BIOGEOGRAPHY
1
Major Benthic Communities
•
Macroalgal
−
Exposed limestone shores and reefs in this
region (eg. Cape Adieu, Nuyts Reef, Cape
Nuyts, Point Bell) are dominated by Ecklonia
radiata and Scytothalia dorycarpa, with
species of Cystophora (C.moniliformis,
C.grevillea, C.platylobium, C.racemosa) as
sub-dominants. In the sheltered areas, reefs
tend to be dominated by the red algae,
Osmundaria prolifera, Amansia pinnatifida
and species of Sargassum (S.heteromorphum,
S.spinuligerum) and Scaberia agardhii as subdominants.
•
Seagrass
−
With this exposed region, seagrass
communities occur in the sheltered lee of
headlands (eg. Point Fowler, Point Sinclair
and Point Bell). Large meadows of Posidonia
(P.sinuosa, P.angustifolia) and Amphibolis
(A.antarctica, A.griffithii) occur in Fowlers
Bay, while smaller meadows occur in Bell and
Sinclair bays.
BIOLOGY
•
Coastal and Offshore Islands (or Reefs)
Major Inshore Habitats
−
Nuyts Reef (south of Cape Adieu).
Major intertidal habitats in the region include
mostly limestone cliffs, and some sandy
beaches.
−
Sinclair Island.
−
Major Rivers/Estuaries
None.
OCEANOGRAPHY
This biounit experiences wave energies ranging
from low in the bays, to high around the offshore
islands and cliffs.
2
GEOLOGY
AND
GEOMORPHOLOGY5
COASTAL
The majority of the coast within this biounit
comprises Pleistocene dune calcarenite cliffs
interspersed
with
Holocene
sediments.
Precambrian crystalline rock forms the bedrock of
all major peninsulas, all islands (excepting Eyre
Island and Nuyts Archipelago) and most headlands,
thereby providing the primary crenulations along
the coast, and acting as a basement for the multiple
episodes of Pleistocene marine - aeolian
transgressions.
The biounit is moderately crenulate with numerous
bays and embayments usually containing Holocene
sediments, separated by headlands and sections of
Pleistocene cliffs.
3
−
−
5
It faces in a
Of the total inshore subtidal habitats mapped
in the biounit (26,439 ha), limestone reefs
comprise 21,666 ha (81.9%), sandy bottoms
comprise 3,134 ha (11.9%), and seagrass
meadows comprise 1,639 ha (6.2%).
From Eyre Coast Protection District Study Report.
Page 28
EYRE REGION – FOWLERS BIOUNIT
MARINE CONSERVATION VALUES
1.2 Physical
Geological Monuments
1
SIGNIFICANT BIOLOGICAL AND
PHYSICAL FEATURES
−
Clare Bay: raised beach with wave cut shore
platforms and lithified beach deposit.
−
Point Le Hunte (by Point Sinclair):
Pleistocene Bridgewater Formation.
2
OTHER VALUES
1.1 Biological
The Great Australian Bight region is best known
for its large cetaceans. At least 17 species of
cetaceans have been recorded in this region, some
of which are migratory species, such as Blue
Whales, Sperm Whales, Minke Whales,
Humpbacks, Rorquals, as well as the Southern
Right Whale (Kemper & Ling 1991). Killer
Whales have also been recorded and their presence
is probably related to the abundance of pinnipeds
along the western Eyre Peninsula.
Critical area for the Southern Right Whale
(Eubalaena australis). Whales are also often seen
moving along the coast towards the Head of Bight.
Groups of as many as five whales have been seen
from the air near Fowlers Bay and pairs or
singletons are now fairly common sights as they
move from bay to bay around the western side of
Eyre Peninsula (Watt & Ling 1985).
They
probably mate, give birth and suckle inshore.
−
−
Nuyts Reef Conservation Park. This cluster of
rocks and reefs represents a significant haul
out site for New Zealand Fur Seals
(Shaughnessy 1990) and a haul out and
breeding site for Australian Sea Lions
(Robinson & Heard 1985, Gales et al. 1994).
Western and Middle Nuyts Reefs have been
identified as breeding sites for sea lions, while
Southern Nuyts Rock and Eastern Nuyts Reef
appear to be haul out sites only (Gales et al.
1994). Colony number has been estimated at
207 (ie. 43 pups) at Western Nuyts Reef and
207 (ie. 43 pups) at Middle Reef (Gales et al.
1994). Sea lion colony numbers vary from
60-120 recorded in 1977 (Robinson & Dennis
1988) to a total of 216 sea lions recorded in
1990 (Gales et al. 1994). Fur seals haul out at
Southern Nuyts Rock and Western Nuyts Reef
(Shaughnessy et al. 1994). A total of 37 fur
seals were recorded in 1990 (Shaughnessy
1990). The park is on the Register of the
National Estate.
2.1 Commercial Fisheries
Major single species fisheries in this region include
Western King Prawn, Abalone and Southern Rock
Lobster. There is also a considerable marine
scalefish fishery targeting mainly King George
Whiting by hand line. Some netting occurs inside
parts of Venus Bay. Some of the Southern Bluefin
Tuna boats use Thevenard as their major port of
landing.
Southern Rock Lobster
In 1995/96 and 1996/97 a total of 10 and 11
licensed operators fished in this area (ie. Fishing
Zone 7), catching approximately 49,122 and 32,461
kg of lobsters, respectively (or 0.961% and 0.64%
of the total catch for Southern Rock Lobster in
South Australian waters).
Abalone
Blacklip Abalone and Greenlip Abalone is
presently commercially harvested within this
biounit. (ie. MapCode 1A-E, Cape Adieu to Point
Bell region), but due to confidentiality constraints
these figures are not available.
Marine Scalefish Fisheries
During 1995/96 and 1996/97, 14 commercial
licence holders (made up of Marine Scalefish,
Restricted Marine Scalefish and Northern Zone
Rock Lobster licence categories) caught
commercial marine scalefish species from this
region (ie. Fishing Zone 7).
Sinclair Island Conservation Park provides a
resting place for Australian Sea Lions (Watt &
Ling 1985, Robinson & Heard 1985, Gales et
al. 1994), New Zealand Fur Seals (Shaugnessy
1990) and Crested Terns. The park is on the
Register of the National Estate.
Page 29
EYRE REGION – FOWLERS BIOUNIT
License holders expended approximately 190 and
280 boat days effort fishing these waters during
1995/96 and 1996/97, respectively. The marine
scalefish catch for this region (ie. Fishing Zone 7)
represented 23 ,972 kg in 1995/96 and 112,894 kg
in 1996/97(or 0.23% and 1.11% of the total catch
for the marine scalefish fishery in South Australian
waters).
Although license holders are not restricted to
fishing in this biounit, the following licenses are
registered in this area:
−
Fowlers Bay: 1 restricted marine scalefish.
−
Ceduna: 6 restricted marine scalefish licenses,
12 unrestricted marine scalefish, 1 Western
King Prawn.
−
Smoky Bay: 5 unrestricted marine scalefish
licenses.
−
Streaky Bay and Haslam: 3 restricted marine
scalefish licenses, 28 unrestricted marine
scalefish, 3 Abalone licenses, 2 Southern Rock
Lobster.
Thevenard: 4 restricted marine scalefish
licenses, 32 unrestricted marine scalefish, 3
Southern Rock Lobster, 1 Western King
Prawn.
−
−
Baird Bay: 2 unrestricted marine scalefish
licenses.
−
Port Kenny: 12 unrestricted marine scalefish
licenses, 1 restricted marine scalefish, 1
Western King Prawn.
−
Venus Bay: 3 unrestricted marine scalefish
licenses.
2.2 Mariculture
There is presently one R&D aquaculture lease in
this region at Fowlers Bay. The Far West
Aquaculture Management Plan (Ashman 1996) has
recommended limited aquaculture development
within this region:
−
2.3 Recreation and Tourism
Fishing
−
−
−
Fowlers Bay Zone (defined waters within
Fowlers Bay) – zoned for potential
aquaculture development and protection of
conservation and fisheries values. Licenses
will be considered for a maximum of 40 ha of
aquaculture development in this zone, after 2
years of R&D.
Scott Bay: beach fishing. Major species: Sand
Flathead, Yelloweye Mullet, Australian
Salmon and Mulloway.
Fowlers Bay, Point Fowler: jetty and rock
fishing. Major species: King George Whiting,
Sand Flathead, Yelloweye Mullet, Australian
Salmon, Snook, Sweep, Garfish, Yellowtail
Kingfish,
Tommy
Rough,
Trevally,
Toothbrush Leatherjacket, Silver Drummer
and Southern Calamari.
Clare Bay: beach fishing. Major species: Sand
Flathead, Yelloweye Mullet, Australian
Salmon, Mulloway, Snook, Sweep, Blue
Groper, Tommy Rough, Trevally, Toothbrush
Leatherjacket and Silver Drummer.
Tourism
The many bays and spectacular coastal scenery of
this biounit are strong tourist attractions in this
region. Major activities include boating, fishing
and swimming.
−
Rocky Point, Point James: camping, SCUBA
diving.
−
Cactus Beach is 21 km south of Penong (east
of Ceduna), and is considered as one of the
best surfing beaches in the world. Although
the surrounding land is privately owned,
camping is allowed by permission of the
owner.
Fowlers Policy Area
−
Point Le Hunte Zone (defined waters on
eastern side of Point Sinclair) - zoned for
potential aquaculture development and
protection of conservation and fisheries
values. Licenses will be considered for a
maximum of 10 ha of aquaculture
development in this zone, after 2 years of
R&D.
2.4 Scientific Research and Education
−
Researchers from the NPWS regularly
conduct surveys of Australian Sea Lion and
New Zealand Fur Seal colonies in the Nuyts
Archipelago region.
Page 30
EYRE REGION – FOWLERS BIOUNIT
−
Fisheries research in this area includes, regular
catch and effort monitoring of the major
commercial fisheries in the region (Abalone,
Southern Rock Lobster, Western King Prawn,
and marine scalefish); regular research and
monitoring of larval fish stocks; regular
research and monitoring of South Rock
Lobster field stocks.
2.5 Adjacent Land Use
National and Conservation Parks
−
Nuyts Reef Conservation Park (29 ha).
−
Sinclair Island Conservation Park (1 ha).
−
Fowlers Bay Conservation Reserve (8,649ha).
−
Chadinga Conservation Reserve (8,125 ha).
−
Point Bell Conservation Reserve (602 ha).
Agriculture/Industry
Most of the adjacent land is used for agriculture.
There are no major industries along the coast.
−
The region between Fowler's Bay and Streaky Bay
is also culturally significant for the dominance of
`natural' Aboriginal fishtraps in this region (Martin
1988). These fishtraps used modified natural
features such as rock platform reef formations, tidal
pools and shellgrit ridges. None of these types of
traps have been recorded elsewhere along the west
coast of Eyre Peninsula.
Within this biounit,
natural Aboriginal fish traps have been found at:
− Rocky Point (1).
The Murat Bay Aquaculture Management Plan
(Bond T. 1991) reports the following areas of
Aboriginal significance in this biounit6:
−
−
−
Urban Centres
None.
2.6 Significant Cultural and Historical Features
The rocky coast of the Point James Zone has
Aboriginal sites of high sensitivity and
moderate significance, whilst the sandy coast
has Aboriginal sites considered to be of
moderate sensitivity and low significance
(Nicholson 1990).
European
Old whaling station at Fowler's Bay.
Shipwrecks
There are records of 7 shipwrecks in this
region. None of these are protected under
Commonwealth legislation. The two oldest
wrecks are the `Spindrift’ (lost in 1927) and
the `Cecelia’ (lost in 1946), both near Point Le
Hunte.
Aboriginal
The region encompassed within Murat Bioregion
(and Fowlers Biounit) represents one of the most
significant regions of Aboriginal heritage along the
whole of the Eyre Province (A. Nicholson
pers.comm.). The remoteness of the region has
resulted in many sites remaining completely
undisturbed by European activities. Nicholson
(1991), in a survey of cultural sites from Fowlers
Bay to Elliston, identified the following occupation
site within this biounit, as being particularly
significant:
−
Point Brown 4 (approximately 400-500 years
old): a recent occupation complex consisting
of middens and an artefact manufacturing site.
To be recommended for National Estate listing
(Nicholson pers.comm.).
3
CURRENT CONSERVATION STATUS
OF THE FOWLERS BIOUNIT
−
Marine Reserves
None.
−
Marine Parks
None
Netting Closures
−
Fowlers Bay (all waters west of a line from
First Point to a point 200 metres north east of
the end of the jetty and then generally
westward to a point on the mainland 200
metres north of the jetty).
6
"Sensitivity" refers to the quantity of sites in a particular region:
the more sites there are in a region, the more "sensitive" it is
thought to be. "Significance" refers to the quality or importance of
sites within a given region and is defined according to certain
criteria such as significance to the archaeological discipline or to
the Aboriginal community.
Page 31
EYRE REGION – FOWLERS BIOUNIT
4
AREAS OF HIGH CONSERVATION
VALUE IN THE FOWLER BIOUNIT
Nuyts Reef- D’Entrecasteux Reef
−
Prime IUCN Conservation Values: rare and
endangered
species/habitats,
biodiversity,
research (IUCN Category IA).
IUCN
Identification Criteria: naturalness (not
subjected to human-induced change), ecological
(breeding site for Australian sea-lion, haul out
site for New Zealand Fur Seals), economic
(Greenlip Abalone, Blacklip Abalone, marine
scalefish fisheries, Southern Rock Lobster),
scientific
(scientific
research/monitoringAustralian Sea Lions), national (Register of the
National Estate–Nuyts Reef Conservation
Park), practicality (insulation, compatibilityadjacent to Nuyts Reef Conservation Park).
social values, biodiversity (IUCN Category III).
IUCN Identification Criteria: naturalness (not
subjected to human-induced change), economic
(Greenlip Abalone, Blacklip Abalone, marine
scalefish fisheries, Southern Rock Lobster),
social (aboriginal fish traps at Rocky Point,
recreation, camping, diving), national
(potential for listing on the Register of the
National Estate), practicality (accessibility).
Fowlers Bay-Clare Bay
−
Primary IUCN Conservation Values:
biodiversity, cultural, social values (IUCN
Category II). IUCN Identification Criteria:
naturalness (not subject to human-induced
change), biogeographic (geological monument
at Clare Bay, representative habitats),
ecological (seagrass meadows at Fowlers Bay
whale resting site, ecological integrity),
economic (Greenlip Abalone, Blacklip Abalone,
marine scalefish fisheries, Southern Rock
Lobster), social (old whaling station, recreation,
tourism,
aesthetic
values),
practicality
(accessibility, compatibility-adjacent to Fowlers
Bay Conservation Reserve).
Sinclair Island – Point Le Hunte
−
Prime IUCN Conservation Values: rare and
endangered
species/habitats,
biodiversity,
cultural values (IUCN Category IA). IUCN
Identification Criteria:
naturalness (not
subjected
to
human-induced
change),
biogeographic (geological monument – Point Le
Hunte, representative habitats), ecological
(breeding site – Crested Terns, haul out site for
Australian sea-lions and New Zealand Fur
Seals, whale resting site), economic (Greenlip
Abalone, Blacklip Abalone, marine scalefish
fisheries, Southern Rock Lobster), social
(shipwrecks - `Sprindrift’, `Cecelia’, recreation,
aesthetic values), national (Register of the
National Estate – Sinclair Island Conservation
Park), practicality (accessibility, compatibilityadjacent to Sinclair Island Conservation Park).
Rocky Point
−
Primary IUCN Conservation Values: cultural,
Page 32
EYRE REGION – STREAKY AND NUYTS BIOUNIT
IV
MARINE BIOGEOGRAPHY AND CONSERVATION VALUES OF THE
STREAKY AND NUYTS BIOUNIT
This coastal region is represented by 2 biounits: the inshore Streaky Biounit (the seaward boundary defined by
the 30 metre coastal bathymetric contour), and an offshore Nuyts Bioregion (which extends down to 50 metre
contour. The Streaky Biounit extends from Point James to Cape Bauer, and covers an area of 190,949ha. The
Nuyts Bioreregion encompasses the Nuyts Archipelago, and covers an area of 283,165ha. The region faces in a
southwesterly direction into the Great Australian Bight.
MARINE BIOGEOGRAPHY
1
OCEANOGRAPHY
These biounits experience wave energies ranging
from low in the bays, to high around the offshore
islands and cliffs.
2
GEOLOGY
AND
GEOMORPHOLOGY7
COASTAL
The majority of the coast within thes biounits
comprise Pleistocene dune calcarenite cliffs
interspersed
with
Holocene
sediments.
Precambrian crystalline rock forms the bedrock of
all major peninsulas, all islands (excepting Eyre
Island and Nuyts Archipelago) and most headlands,
thereby providing the primary crenulations along
the coast, and acting as a basement for the multiple
episodes of Pleistocene marine - aeolian
transgressions.
The Streaky Biounit is highly crenulate with
numerous bays and embayments usually containing
Holocene sediments, separated by headlands and
sections of Pleistocene cliffs.
There are three large coastal embayments within
the inshore Streaky Biounit (Tourville Bay,
Bosanquet Bay, Decres Bay, Smoky Bay and
Streaky Bay) and numerous offshore islands within
the offshore Nuyts Biounit, including the Nuyts
Archipelago, Lacy Islands, Evans Island and
Flinders Reef, and the Isles of St. Francis.
The Nuyts Archipelago group of islands consists of
Purdie Island (the largest) and a number of small
islands and reefs, all of crystalline basement. Only
Purdie Island has a cover of calcareous aeolianite.
Lounds Island is an elongate outcrop of crystalline
basement.
7
Lacy Islands consist of Lacy Island (the largest)
and several smaller islands.
Lacy Island is
crystalline basement with a cover of calcareous
aeolianite, Bridgewater Formation which forms a
prominent platform at the base of the island. The
smaller islands appear to be wholly crystalline
basement (Kinsman 1973).
Evans Island is crystalline basement covered by a
thick, fairly flat blanket of aeolianite.
The
basement forms a platform around the whole island
and several rocky outcrops just offshore. Flinders
Reef consists of two small islands of crystalline
basement.
The Isles of St. Francis consist of six major islands
and several smaller islands. The larger islands are
Egg, Dog, West, St. Francis, Masillon and Fenelon
Islands. Egg island is crystalline basement covered
by calcareous aeolianite which forms a broad
platform around the entire island. An unnamed
island south of Egg Island is also aeolianite on
crystalline basement. Dog Island is crystalline
basement with a cover of calcareous aeolianite, as
is an unnamed island to the north-east of Dog
Island. West Island is crystalline basement with a
limited cover of aeolianite. St. Francis Island is the
largest island in the group and is crystalline
basement covered with a thick layer of aeolianite.
In several areas, beaches are formed in
embayments. Masillon and Fenelon Islands are
similar, with crystalline basement outcrops at the
base of each island and a thick cover of aeolianite,
with one small embayment. Hart Island is an
elongate outcrop of crystalline basement, but there
is no aeolianite.
Cannan Reefs, approximately 7km south-west of
Fenelon Island, are wholly crystalline rocks.
Yatala Reef and Goat Island are both crystalline
basement, with Goat Island also having a thick
cover of aeolianite. Franklin Island is virtually two
islands joined superficially by a sand bar but is
most probably underlain by crystalline basement;
as is the remainder of the island and the small
islands nearby.
From Eyre Coast Protection District Study Report.
Page 33
EYRE REGION – STREAKY AND NUYTS BIOUNIT
Caulerpa Cactoides.
Franklin Island has a thick cover of calcareous
aeolianite covered by low vegetation, with recent
sands forming narrow beaches on the northern side
(Kinsman 1973).
3
BIOLOGY
Major Inshore Habitats
−
−
Major intertidal habitats in the region include
bays and `estuaries’ (ie. mangroves,
saltmarshes, mudflats), offshore islands, sandy
beaches and limestone rocky shores.
Of the total inshore subtidal habitats mapped
in the Streaky Biounit (110,972ha), seagrass
meadows comprise 86,163ha (77.6%), sandy
bottoms comprise 22,466ha (20.2%), and
limestone reefs comprise 2,343ha (2.1%). Of
the total inshore subtidal habitats mapped in
the Nuyts Biounit (2,711ha), limestone reefs
comprise 2,483 (91.6%), seagrass meadows
comprise 144ha (5.3%), sandy bottoms
comprise 84ha (3.1%).
Major Benthic Communities
•
Macroalgal
−
Rocky limestone shores and reefs vary from
wave exposed), to sheltered, in the lee of
islands and headlands, and also, along coasts
protected by the Nuyts Archipelago. Along
exposed coasts (eg. Point Brown, Cape de
Mole, Cape Bauer), reefs are dominated by
Ecklonia radiata and Scytothalia dorycarpa
and articulated (Amphiroa, Metagoniolithon)
and encrusting corallines, with species of
Cystophora (eg. C.racemosa) as subdominants. On moderately exposed coasts
(eg. Cape D’Estrees), reefs are dominated by
species of Sargassum (S.lacerifolium and
S.spinuligerum,
S.heteromorphum,
S.decipiens, S.verruculosum, S.paradoxum),
with Cystophora monilifera, Caulocystis
ulvifera, and Osmundaria prolifera, as subdominants.
•
Seagrass
−
Large seagrass dominated embayments occur
in this region (ie. Tourville, Murat, Bosanquet,
Decres and Smoky bays) and also, adjacent to
Eyre and St Peter Islands. Many species of
seagrass occur in this area, and meadows are
typically dominated by species of Posidonia
(P.australis, P.sinuosa), and Heterozostera
tasmanica in shallower regions. The seagrass
Halophila australis typically occurs as a subdominant, sometimes with the green alga,
Coastal and Offshore Islands (or Reefs)
These biounits are characterised by many coastal
and offshore islands. Many of them have a variety
of habitats including sandy beaches, seagrass
meadows and algal assemblages and rocky shores.
On the islands themselves, large bird colonies or
colonies of the New Zealand Fur Seal or the
Australian Sea Lion are often present. These are
detailed below.
•
Nuyts Archipelago, comprising:
−
−
Purdie, Purdie Rocks, Lounds Island,
Lacy, Evans, Goat, St Peter, Eyre Islands
•
Flinders Reef
−
Franklin Islands: South Franklin Rocks, small
South Franklin Island, Franklin Island, small
NE Franklin Island
−
St. Francis Isles: Freeling, Smooth, Egg, Dog,
West, St. Francis, Masillon, Fenelon and Hart
Islands
•
Cannon Reefs
•
Eba Island
•
Pigface Island
•
Olive Islands
Major Rivers/Estuaries
Because of the arid nature of this region, all the
estuaries in the Streaky Biounit are not `true'
estuaries but rather `reverse estuaries'. However,
since they exhibit typical estuarine flora and fauna,
they are considered as `estuarine habitats'.
−
−
−
−
−
−
−
−
Tourville Bay.
Murat Bay.
Denial Bay.
Bosanquet Bay.
Smoky Bay.
Blanche Port (Streaky Bay).
Laura Bay.
Acraman Creek.
Page 34
EYRE REGION – STREAKY AND NUYTS BIOUNIT
19 waterbirds have been recorded for the bay,
11 of these are listed under international
treaties (Fuhlbohm 1992). White-bellied Sea
Eagles and Ospreys breed in nearby cliffs.
Approximately 3,500-5,000 waders utilise the
area (Eckert 1974). Streaky Bay has been
identified as an area of international
importance for shorebirds by Watkins (1993).
MARINE CONSERVATION VALUES
1
SIGNIFICANT
BIOLOGICAL
PHYSICAL FEATURES
AND
1.1 Biological
Coastal and Marine Wetlands of National
Importance
−
−
Tourville Bay (Davenport Creek) has been
identified as a wetland of national importance
(see ANCA 1996). The mangroves in this bay
represent not only the western-most extent of
mangroves (Avicennia marina) in South
Australia, but also, the largest stand of
mangrove forest on Eyre Peninsula. They also
form the most extensive stand of mangroves
between Spencer Gulf and Exmouth Gulf in
Western Australia.
The mangroves of
Davenport Creek in particular, are growing on
a more sandy substrate than is usual for South
Australian mangroves. Most of the bay is less
than 2m deep, and consists of intertidal
sand/mud flats (42 km2); mangroves (13 km2);
samphire; seagrass and reefs (Bucher &
Saenger 1989). The estuary itself is a nursery
area for fish and Western King Prawns and a
feeding area for waders, and as such, it is one
of the most important coastal wetlands in the
state (Bond T., 1991). Tourville Bay was
identified as an area of international
importance for shorebirds by Watkins (1993).
Threatened species include Hooded Plover,
Thinornis rubricollis (Nv, Sv) and Eastern
Curlew, Numenius madagascariensis (Sv).
Breeding sites have been recorded for Pied
Cormorants, Phalacrocorax varius, Grey
Cormorants, P.carbo and White-faced Herons,
Egretta novaehollandiae (Watkins 1993). In
a review of estuaries in Australia, Bucher &
Saenger (1989) identified Tourville Bay as
one of three estuaries of outstanding
conservation value in South Australia.
Streaky Bay (including Acraman Creek) has
been identified as a wetland of national
importance (see ANCA 1996). The bay is a
major waterbird feeding and roosting area for
the west coast of South Australia, while
Acraman Creek is one of the finest examples
of diverse samphire vegetation on the Eyre
Peninsula (ANCA 1996). Threatened plant
species include Halosarcia flabelliformis (Nv,
Sv) and Centrolepis cephaloformis (Sr) at
Acraman Creek. Threatened fauna include
Hooded Plover, Thinornis rubricollis (Nv,
Sv). White-bellied Sea-Eagle, Haliaeetus
leucogaster (Sv), Osprey, Pandion haliaetus
(Sv), Cape Barren Goose, Cereopsis
novaehollandiae (Sv) and Eastern Curlew,
Numenius madagascariensis (Sv). A total of
−
Both Smoky Bay and Streaky Bay estuaries
support substantial areas of marine wetlands
(ie. mangroves, seagrass) that would provide
habitat for estuarine and offshore fish stocks.
Smoky Bay consists of intertidal sand/mud
flats (10.54 km2 - with Heterozostera
tasmanica); mangroves (7.62 km2); and very
dense sand 1m high with samphire and
patches of low Sarcocornia (Bucher &
Saenger 1989). Blanche Port (Streaky Bay):
consists of intertidal sand/mud flats (7.19
km2); mangroves (3.42 km2); and scattered
areas of Sarcocornia within the mangroves
(Butler et al. 1975). The size of the estuaries
and the extent and diversity of their associated
wetlands suggest that they contribute
significantly to the ecology of the local area
(Bucher & Saenger 1989).
Smoky Bay
particularly is an important nursery area for
fish and Western King Prawns. The oyster
zone was found to be the only area to have
abundant juvenile Western King Prawns in
Smoky Bay (Wallner 1985). The mangroves
in the north of the zone are a substantial stand
but not significant locally.
Other Areas of Significance
−
Murat, Denial and Bosanquet Bays support
substantial areas of wetland that would
provide habitat for estuarine and offshore fish
stocks. Murat Bay has extensive beds of razor
shells in the bay. Seagrass is the dominant
marine vegetation with brown algae on
limestone reef areas. Denial Bay has scattered
stands of mangroves and seagrasses that
dominate vegetation in sandy areas, with
brown algae on the reefs.
The marine
environment is an important nursery area for
Western King Prawns and fish especially the
area from the jetty to Low Point (Wallner
1985). Bosanquet Bay consists of seagrass,
reef areas and a small stand of mangroves in
the northwest corner of the bay. The shallow
sandy coast of the northern shore of the bay is
important as a nursery area for Western King
Prawns (Wallner 1985).
Page 35
EYRE REGION – STREAKY AND NUYTS BIOUNIT
The size of the estuaries and the extent and
diversity of their associated wetlands suggest
that they would contribute significantly to the
ecology of the local area.
−
Wittelbee Conservation Park: on the Register
of the National Estate.
−
Laura Bay Conservation Park: sandflats are an
important feeding area for waders. The island
off Dog Fence Point is also an important
roosting area for cormorants and gulls. Laura
Bay itself is a sheltered bay with an extensive
sand dune system and is reknown as an area of
outstanding scenic qualities. Fox Creek is a
small tidal creek that flows from the park into
Laura Bay and is lined with mangroves and
saltmarsh.
Several different coastal
environments have been conserved within the
park. The park is on the Register of the
National Estate.
Extensive Seagrass Meadows
−
The seagrasses in the Streaky Biounit
represent the largest areas of seagrass on the
Eyre Coast. The sheltered embayments of the
Eyre Coast, particularly Streaky and Smoky
Bay (ie. Streaky Biounit), and Port Douglas
(ie. Douglas Biounit), support extensive
seagrass meadows. These extensive seagrass
meadows flourish in shallow clear waters,
generally in waters less than 15m, and provide
the basis for the significant productivity of the
coastal regions in terms of fisheries and prawn
production. Seagrasses cover a total area of
approximately 86,163 ha in Streaky and
Smoky Bay, and 8,567 ha in Port Douglas.
Together, the seagrasses of the Eyre Coast
represent approximately 15% (ie. 1407 km2)
of the total area of seagrasses recorded in
South Australia (ie. 9,612 km2).
Inshore Islands of Conservation Value
−
St Peter Island: high conservation value. The
sand banks surrounding the island are
important Western King Prawn nursery areas
and rare shell fish have been recorded here.
The mangrove, sand bank and seagrass
environments around the island are important
fish nursery areas. Brush-tailed Bettongs and
Stick Nest Rats have been re-introduced to the
island.
−
Eyre Islands: Eyre Island, Little Eyre Island,
Goalen Rocks, and Cape Missiessy. The
vegetation on these islands is completely
undisturbed. Eyre Island and Cape Missiessy
in particular have significant samphire and
mangrove cover. Around the islands and
coast, seagrass meadows dominate. The sand
banks north of Eyre Island and east of Cape
Missiessy are important Western King Prawn
nursery areas (Wallner 1985).
−
Eba Island Conservation Park is connected to
the mainland by a long sand bar. The park is
on the Register of the National Estate.
−
Pigface Island Conservation Park has a
breeding colony of Little Black Cormorant
(Phalacrocorax sulcirostris). The park is on
the Register of the National Estate.
Offshore Islands of Conservation Value
−
The offshore islands in the Nuyts Biounit
represent significant breeding sites for the rare
Australian Sea Lion (Neophoca cinerea) and
haul out sites for the New Zealand Fur Seal
(Arctocephalus forsteri) in South Australia.
The islands of the Nuyts Archipelago are
particularly important as breeding sites for
Australian Sea Lions. Significant breeding
colonies occur on Purdie Island (120 pups,
estimated population 577), Lounds Island (26
pups, estimated population 125), West Island
(30 pups, estimated population 144), Fenelon
Island (50 pups, estimated population 241),
Small NE Franklin Island (50 pups, estimated
population 241), Small South Franklin Island
(75 pups, estimated population 361), Olive
Island (50 pups, estimated population 241),
and Jones Island (5 pups, estimated population
24) (Robinson & Heard 1985, Gales et al.
1994).
Haul out sites also occur on Sinclair, Hart,
Purdie, Egg, Smooth, Dog, Freeling, Masillon,
South Franklin Rocks, Lacy and Evans islands
(Watts & Ling 1985, Gales et al. 1994). New
Zealand Fur Seals also haul out on Fenelon,
Lacy and Hart Islands (Shaughnessy et al.
1994).
Page 36
EYRE REGION – STREAKY AND NUYTS BIOUNIT
−
Nuyts Archipelago Conservation Park
includes a wide variety of habitats and
limestone capped islands on massive granite
bases. Apart from the relatively pristine
environment, the most significant thing about
this island group is the presence on the
Franklin Islands of the last known population
in the world of Greater Stick-nest Rats
(Leporillus conditor).
Because of its
importance to conservation, Franklin Island
has been proclaimed a Prohibited Area. This
island also supports a subspecies of Southern
Brown Bandicoot. Most of the other islands
have large Short-tailed Shearwater breeding
colonies in the summer months. Many of
these islands also support significant breeding
colonies or haul out sites for rare Australian
Sea Lions and to a lesser extent New Zealand
Fur Seals (see above). The mangroves present
on St Peter Island are the only oceanic stand
on the entire South Australian coast. Goat and
Franklin islands have dense populations of
very large Black Tiger Snakes.
−
The park is on the Register of the National
Estate.
−
Isles of St Francis Conservation Park:
comprises St Francis, Dog, Smooth, Egg,
West, Masillon, Fenelon and Hart Islands. St
Francis is home to an enormous breeding
population of Short-tailed Shearwaters, a
population of Island Bandicoots (Isoodon
obesulus) and a variety of reptiles, including
an important population of Carpet Python.
There is also a program to reintroduce Brushtailed Bettongs on the island. The other
islands of the St Francis Group are much less
disturbed than the main island and are
biologically interesting in their own right.
Many of the islands are breeding colonies or
haul out sites for Australian Sea Lions (see
above). A breeding colony of New Zealand
Fur Seals is also present on Fenelon Island.
Extensive seagrass meadows and algal
assemblages also occur around the islands,
together with abundant fish fauna including
Blue Groper. The park is on the Register of
the National Estate.
Populations of native bush rats occur on Dog
Island, Masillon Island, Lacy Island, and Goat
Island.
−
Olive Islands Conservation Park, off Cape
Bauer. The park is home to a breeding colony
of more than 150 Australian Sea Lions (Watts
& Ling 1985). The park is on the Register of
the National Estate.
−
The Great Australian Bight region is best
known for its large cetaceans. At least 17
species of cetaceans have been recorded in
this region, some of which are migratory
species, such as Blue Whales, Sperm Whales,
Minke Whales, Humpbacks, Rorquals, as well
as the Southern Right Whale (Kemper &
Ling). Killer Whales have also been recorded
and their presence is probably related to the
abundance of pinnipeds along the western
Eyre Peninsula.
−
Critical area for the Southern Right Whale
(Eubalaena australis). Whales are also often
seen moving along the coast towards the Head
of Bight. Groups of as many as five whales
have been seen from the air near Fowlers Bay
and pairs or singletons are now fairly common
sights as they move from bay to bay around
the western side of Eyre Peninsula (Watt &
Ling 1985). They probably mate, give birth
and suckle inshore.
1.2 Physical
Geological Monuments
−
Laura Bay: Holocene beach ridge system. At
Laura Bay a Holocene beach ridge system has
prograded 1,200m into the bay with
considerable variation occurring in the spacing
and height of the beach ridges. Although the
beach ridge system to some degree reflects the
local conditions of the embayment, it also
reflects the conditions (whether changes in
storminess or sea-level) that have determined
the rates and episodes of Holocene
sedimentation along the western portion of the
Eyre coast.
−
Eyre Island: Holocene beach - foredune ridge
systems. Eyre Island evolved during the
Holocene as a series of multiple beach foredune ridges that prograded simultaneously
on 3 fronts with extensive samphire and
mangrove flats between the prograding arms.
The island represents an island in the making
and preserves a rich history of sea-levels and
sedimentation during the Holocene.
−
Point Brown: dykes on the wave-cut platform.
Page 37
EYRE REGION – STREAKY AND NUYTS BIOUNIT
Point Collinson (northern Streaky Bay):
Pleistocene wave-cut platform. At Point
Collinson a Pleistocene wave-cut platform
1.0m above MSL is overlain by two small
coqioma remnants 0.4-0.6m thick. One of
these contains intact bivalves, including
Anadara spp. The site provides evidence of
previous sea-level events.
In 1995/96 and 1996/97 a total of 17 and 13
licensed operators fished in the Streaky Biounit (ie.
Fishing Zone 10), catching approximately 11,710
and 12,171 kg of lobsters, respectively (or 0.23%
and 0.24% of the total catch for Southern Rock
Lobster in South Australian waters).
−
Acraman Creek: stranded tidal creek system.
Five kilometres west of Acraman Creek a tidal
creek system has been cut off from the sea by
a prograding recurved spit. The stranded
creek system is well preserved and readily
accessible by vehicle, making it an excellent
research site.
−
The barrier-spit sequence is also well
preserved and provides a record of
sedimentation over the Holocene period.
2
OTHER VALUES
Blacklip Abalone and Greenlip Abalone is
presently a significant fishery within the Nuyts
Biounit. In 1994/95 and 1995/96 a total of 20,670
and 15,807 kg of Greenlip was harvested within
this region (ie. MapCode 2A-H, 2J, 3C-D, Nuyts
Archipelago region, Franklin Islands), and
represented 9.1% and 7.0% of the total Greenlip
Western Zone catch (or 5.49% and 4.22% of the
total catch for Greenlip in South Australian
waters). In 1994/95 and 1995/96 a total of 21243
and 16611 kg of Blacklip was harvested within this
region, and represented 6.8% and 6.0% of the total
Blacklip Western Zone catch (or 4.30% and 3.59%
of the total catch for Blacklip in South Australian
waters).
−
2.1 Commercial Fisheries
Major single species fisheries in this region include
Western King Prawn, Abalone and Southern Rock
Lobster. There is also a considerable marine
scalefish fishery targeting mainly King George
Whiting by hand line. Some netting occurs inside
parts of Venus Bay. Some of the Southern Bluefin
Tuna boats use Thevenard as their major port of
landing.
Western King Prawn
This biounit is located within the waters of the
West Coast prawn fishery, which comprises 3
license holders (ie. Boats). All vessels fish within
the waters of this biounit (ie. Fishing Zones 8), the
Newland Biounit (ie. Fishing Zone 15) and the
Douglas Biounit (ie. Fishing Zone 27). In 1995/96
and 1996/97 a total of 200,764 and 166,414 kg was
caught for this fishery, with a total effort of 3,144
and 2,778 hours, respectively (or 8.84% and 8.22%
of the total catch for Western King Prawn in South
Australian waters).
Southern Rock Lobster
Abalone
The Blacklip Abalone and Greenlip Abalone is
considerably less within the waters of the Streaky
Biounit. (ie. MapCode 3A, Smoky Bay, Cape
Missiessy – Point Collinson region), and
represented 0.1% and 0.8% of the total Greenlip
Western Zone catch (or 0.06% and 0.50% of the
total catch for Greenlip in South Australian
waters), but due to confidentiality constraints these
figures are not available.
Marine Scalefish Fisheries
During 1995/96 and 1996/97, 19 and 21
commercial licence holders (made up of Marine
Scalefish, Restricted Marine Scalefish and
Northern Zone Rock Lobster licence categories)
caught commercial marine scalefish species from
the Nuyts Biounit (ie. Fishing Zone 8),
respectively.
License holders expended
approximately 1,141 and 1,334 boat days effort
fishing these waters during 1995/96 and 1996/97,
respectively. The marine scalefish catch for this
region (ie. Fishing Zone 8) represented 173,574 kg
in 1995/96 and 196,644 kg in 1996/97(or 1.67%
and 1.94% of the total catch for the marine
scalefish fishery in South Australian waters).
In 1995/96 and 1996/97 a total of 19 and 18
licensed operators fished in the Nuyts Biounit (ie.
Fishing Zone 8), catching approximately 54,832
and 43,345 kg of lobsters, respectively (or 1.07%
and 0.85% of the total catch for Southern Rock
Lobster in South Australian waters).
Page 38
EYRE REGION – STREAKY AND NUYTS BIOUNIT
During 1995/96 and 1996/97, 26 and 28
commercial licence holders (made up of Marine
Scalefish, Restricted Marine Scalefish and
Northern Zone Rock Lobster licence categories)
caught commercial marine scalefish species from
the Streaky Biounit (ie. Fishing Zone 10),
respectively.
License holders expended
approximately 1929 and 2,043 boat days effort
fishing these waters during 1995/96 and 1996/97,
respectively. The marine scalefish catch for this
region (ie. Fishing Zone 10) represented 64,455 kg
in 1995/96 and 73,702 kg in 1996/97(or 0.62% and
0.73% of the total catch for the marine scalefish
fishery in South Australian waters).
Although license holders are not restricted to
fishing in this biounit, the following licenses are
registered in this area:
−
Fowlers Bay: 1 restricted marine scalefish.
−
Ceduna: 6 restricted marine scalefish licenses,
12 unrestricted marine scalefish, 1 Western
King Prawn.
−
Smoky Bay: 5 unrestricted marine scalefish
licenses.
Streaky Bay and Haslam: 3 restricted marine
scalefish licenses, 28 unrestricted marine
scalefish, 3 Abalone licenses, 2 Southern
Rock Lobster.
−
−
Thevenard: 4 restricted marine scalefish
licenses, 32 unrestricted marine scalefish, 3
Southern Rock Lobster, 1 Western King
Prawn.
−
Baird Bay: 2 unrestricted marine scalefish
licenses.
−
Port Kenny: 12 unrestricted marine scalefish
licenses, 1 restricted marine scalefish, 1
Western King Prawn.
−
Venus Bay: 3 unrestricted marine scalefish
licenses.
Ceduna Policy Area
−
Denial Bay Aquaculture Zone (waters of
Denial Bay, west to Cape Beaufort) – zoned
for sustainability of existing oyster culture
industry. Licenses will be considered for a
maximum of 122ha of oyster culture within
this zone.
−
Smoky Bay Aquaculture Zone (southern
waters of Streaky Bay) – zoned for
sustainability of existing oyster culture
industry. Licenses will be considered for a
maximum of 85ha of oyster culture within this
zone.
−
Tourville Bay Zone (waters at the mouth of
Tourville Bay) – zoned to assess potential
aquaculture (oyster fattening). Licenses will
be considered for maximum of 2ha of R&D
oyster culture.
−
Murat Bay Zone (waters of Murat Bay) zoned for assess potential aquaculture (oyster
fattening). Licenses will be considered for
maximum of 2ha of R&D oyster culture.
−
St Peter Island Zone (waters off southeastern
end of island) - zoned to assess potential
aquaculture (oyster fattening). Licenses will
be considered for maximum of 2ha of R&D
oyster culture.
−
D’Ecres Bay Zone (waters of D’Ecres Bay,
from Cape Vivonne to Cape D’Estres,
excluding
waters
adjacent
Wittlebee
Conservation Park) – zoned for aquaculture
development. Licenses will be considered for
a maximum of 40ha of aquaculture
development.
−
Waterwitch Zone (waters of Smoky Bay,
excluding waters adjacent to Laura Bay and
Laura Bay Conservation Park) - zoned for
aquaculture development. Licenses will be
considered for a maximum of 80ha of
aquaculture development.
−
Licenses will not be considered for
aquaculture developments outside these zones,
including Purdie Islands, St Francis Isles,
Franklin Islands.
2.2 Mariculture
Pacific Oyster farming is the major mariculture
industry in this coastal biounit. At present this
region represents one of the major regions for
oyster growing in South Australia. As such,
significant activity is present in Denial Bay (116 of
leases), western Blanche Port (or Streaky Bay) and
eastern Smoky Bay. The Far West Aquaculture
Management
Plan
(Ashman
1996)
has
recommended consolidation of the existing oyster
industry within this region:
Page 39
EYRE REGION – STREAKY AND NUYTS BIOUNIT
2.3 Recreation and Tourism
−
Fisheries research in this area includes, regular
catch and effort monitoring of the major
commercial fisheries in the region (Abalone,
Southern Rock Lobster, Western King Prawn,
and marine scalefish); regular research and
monitoring of larval fish stocks; regular
research and monitoring of South Rock
Lobster field stocks.
−
Islands in the St Francis Group (St Francis,
Egg, Masillon, and Fenelon) have been the
site of a number of marine and terrestrial
ecological studies by both, fisheries
researchers and researchers from the SA
Museum and research institutions (see
Shepherd & Womersley 1976).
Fishing
−
−
Ceduna: jetty, boat and shore fishing. Major
species: King George Whiting, Sand Flathead,
Yelloweye Mullet, Australian Salmon,
Snapper, Snook, Garfish, Blue Groper,
Tommy Rough, Trevally and Southern
Calamari.
Smoky Bay, Point Brown: boat, jetty and rock
fishing. Major species: King George Whiting,
Sand Flathead, Yelloweye Mullet, Australian
Salmon, Snapper, Snook, Sweep, Garfish,
Tommy Rough, Trevally, Toothbrush
Leatherjacket and Southern Calamari.
2.5 Adjacent Land Use
−
−
Streaky Bay, Back Beach: boat, jetty and
shore fishing. Major species: King George
Whiting, Sand Flathead, Yelloweye Mullet,
Australian Salmon, Snapper, Mulloway,
Snook, Garfish, Greenback Flounder, Blue
Swimming Crab, Tommy Rough, Trevally,
Toothbrush Leatherjacket and Southern
Calamari.
National and Conservation Parks
−
Nuyts Archipelago Conservation Park (5483
ha): includes all remaining offshore islands
between Rocky Point and Point Brown, with
the exception of St Peters Island which is held
under a Pastoral Lease, and Evans Island
which is a lighthouse Reserve managed by the
Commonwealth Government.
−
Isles of St Francis Conservation Park (1,320
ha): comprises St Francis, Dog, Smooth, Egg,
West, Masillon, Fenelon and Hart Islands.
−
Wittelbee Conservation Park (153 ha).
−
Laura Bay Conservation Park (267 ha).
−
Acraman Creek Conservation Park (3,960ha).
−
Caratoola Recreation Park (53 ha).
−
Eba Island Conservation Park (121 ha).
−
Pigface Island Conservation Park (10 ha).
−
Olive Islands Conservation Park (21 ha).
There is an artificial reef located in Streaky
Bay (consisting of 100 rubber tyre modules).
Tourism
The many bays and spectacular coastal scenery of
this biounit are strong tourist attractions in this
region. Major activities include boating, fishing
and swimming.
−
Davenport Beach: swimming.
−
Ceduna: watersports, swimming, visiting
Oyster Farms. Fishing or touring trips run to
the local bays, as well as 4WD or helicopter
tours along the coast.
2.4 Scientific Research and Education
−
Researchers from the NPWS regularly
conduct surveys of Australian Sea Lion and
New Zealand Fur Seal colonies in the Nuyts
Archipelago region. Regular counts of the
Point Labatt colony have been made since
1966 (Robinson & Heard 1985).
Agriculture/Industry
Most of the adjacent land is used for agriculture.
There are no major industries along the coast.
The jetty at Thevenard is the principal port on the
West Coast for shipping grain, gypsum and salt.
The Yatala Channel provides access to the jetty and
is dredged and maintained by the Department of
Marine and Harbours. International ships frequent
this port.
Page 40
EYRE REGION – STREAKY AND NUYTS BIOUNIT
Urban Centres
−
Ceduna (population 2,877).
−
Streaky Bay (population 992).
2.6 Significant Cultural and Historical Features
Aboriginal
The region encompassed within the Murat
Bioregion (and Nuyts Biounit) represents one of
the most significant regions of Aboriginal heritage
along the whole of the Eyre Province (A.
Nicholson pers.comm.). The remoteness of the
region has resulted in many sites remaining
completely undisturbed by European activities.
Nicholson (1991), in a survey of cultural sites from
Fowlers Bay to Elliston, identified the following
occupation sites as being particularly significant:
−
−
Acraman Creek 4 (approximately 6,700 years
old): a discrete occupation site consisting of
four middens.
To be recommended for
National
Estate
listing
(Nicholson
pers.comm.).
−
Natural Aboriginal fish traps have been found
at Rocky Point (1), Tourville Bay (2), Murat
Bay (10), Halfway Camp, in Murat Bay (1),
Point Dillon-Cape Missiessy (1), Smoky Bay
(1), and Eba Island (1) (Martin 1988).
−
`Constructed' Aboriginal fishtraps, consisting
of woven wooden traps, have been recorded at
Duckponds Creek, in Murat Bay (1) and on
the north coast of St Peter Island (1) (Martin
1988).
The Murat Bay Aquaculture Management Plan
(Bond. T, 1991) reports the following areas of
Aboriginal significance in this region8:
−
The rocky coast of the Point James Zone has
Aboriginal sites of high sensitivity and
moderate significance, whilst the sandy coast
has Aboriginal sites considered to be of
moderate sensitivity and low significance
(Nicholson 1990).
−
The rocky coast occupied by Ceduna and
Thevenard probably had Aboriginal sites of
high sensitivity and moderate significance, but
unfortunately most of this area is now highly
developed and the sites disturbed (Nicholson
1990).
−
Aboriginal sites along Cape Beaufort are
considered to be of high sensitivity and
moderate significance (Nicholson 1990).
−
The rocky coast of the Waterwitch
Aquaculture Zone has Aboriginal sites of high
sensitivity and moderate significance; the
sandy coast has sites of high sensitivity and
low significance. The beach east of Wittlebee
Point and the southern part of Smoky Bay
have sites of moderate sensitivity and
significance.
Corvisart Bay 3, Granites (approximately 67,000 years old): a discrete occupation site
consisting of three middens.
To be
recommended for National Estate listing
(Nicholson pers.comm.).
In addition to these outstanding sites a number of
other occupation sites of cultural significance have
also been identified by Nicholson (1991):
−
The region between Fowler's Bay and Streaky Bay
is also culturally significant for the dominance of
`natural' Aboriginal fishtraps in this region (Martin
1988). These fishtraps used modified natural
features such as rock platform reef formations, tidal
pools and shellgrit ridges. None of these types of
traps have been recorded elsewhere along the west
coast of Eyre Peninsula.
Tourville Bay 7, Nadir Landing: a discrete
occupation site: an artefact or stone scatter.
One of the ten largest occupation sites in the
Eyre Province. Tourville Bay as a region is
considered to be of moderate Aboriginal
significance and sensitivity, however the
rocky coast within the bay is considered to be
of high sensitivity and moderate significance
(Nicholson 1990).
−
Perlubie 2, near Eba Island: a discrete
occupation site 20 m from MHWM: an
artefact or stone scatter. One of the ten largest
occupation sites in the Eyre Province.
−
Corvisart 7, Yanerbie sandpatch: a discrete
occupation site consisting of cultural, animal
bones.
8
"Sensitivity" refers to the quantity of sites in a particular region:
the more sites there are in a region, the more "sensitive" it is
thought to be. "Significance" refers to the quality or importance of
sites within a given region and is defined according to certain
criteria such as significance to the archaeological discipline or to
the Aboriginal community.
Page 41
EYRE REGION – STREAKY AND NUYTS BIOUNIT
−
The rocky coast of the Wittlebee Zone has
Aboriginal sites of high sensitivity and
moderate significance.
4
−
In Laura Bay, sites of high sensitivity and
moderate significance occur on rocky coast,
while sites of moderate sensitivity and
significance in sandy areas.
4.1 Streaky Biounit
Tourville Bay
−
European
−
The shipwreck of `Eleni K' (1966) lies in 10m
of water, 1.5 km north of Goat Island.
3
CURRENT CONSERVATION STATUS
OF THE STREAKY AND NUYTS
BIOUNITS
3.1 Streaky Biounit
−
Marine Reserves
None.
−
Marine Parks
None.
−
Netting Closures
Denial and Smoky Bays (all waters east of a
line from Point Brown to Point James)
Streaky Bay
−
−
3.2 Nuyts Biounit
Marine Reserves
None.
−
Marine Parks
None.
−
Netting Closures
None.
Prime
IUCN
Conservation
Values:
biodiversity, cultural, social values (IUCN
Category IA). IUCN IUCN Identification
Criteria: naturalness (not subject to humaninduced
change),
biogeographic
(representative
habitats),
ecological
(mangroves and wetlands at Tourville Baylargest stand on Eyre Peninsula, threatened
waterbirds – Hooded Plover, Eastern Curlew,
breeding sites – Pied Cormorants, Grey
Cormorant, White-faced Heron, ecological
integrity), economic (nursery area for
economic species-Western King Prawn,
marine scalefish, crustaceans), social
(aboriginal fish traps at Rocky Point,
Tourville Bay, aboriginal occupation site at
Tourville
Bay,
recreation,
tourism),
national/international (Wetland of National
Significance, international importance for
shorebirds),
practicality
(accessibility,
insulation).
Decres Bay
(all waters east of a line from Point de Mole to
Cape Bauer, Wandoma)
−
AREAS OF HIGH CONSERVATION
VALUE IN THE STREAKY AND NUYTS
BIOUNITS
Prime IUCN Conservation Values: social
values, biodiversity, (IUCN III).
IUCN
Identification Criteria: naturalness (not
subjected
to
human-induced
change),
biogeographic
(representative
habitats),
ecological (seagrass meadows), economic
(marine
scalefish
fisheries),
social
(recreation), national (Register of the National
Estate-Wittlebee
Conservation
Park),
practicality
(accessibility,
insulation,
compatibility-adjacent
to
Wittlebee
Conservation Park).
Laura Bay – Smoky Bay
−
Prime
IUCN
Conservation
Values:
biodiversity, cultural, social values (IUCN II).
IUCN Identification Criteria: naturalness
(not subjected to human-induced change),
biogeographic
(representative
habitats,
geological monuments-Laura Bay), ecological
(diversity of marine habitats, mangroves at
Laura Bay, extensive seagrass meadows in
Smoky Bay and Laura Bay, ecological
integrity), economic (key nursery areas for
Western King Prawn, marine scalefish
fisheries), social (aboriginal fish traps at
Point Dillon-Cape Missiessy, Smoky Bay,
aesthetic
values-Laura
Bay),
national
Page 42
EYRE REGION – STREAKY AND NUYTS BIOUNIT
(Register of the National Estate-Laura Bay
Conservation Park), practicality (accessibility,
insulation, compatibility-adjacent to Laura
Bay Conservation Park).
4.2 Nuyts Biounit
−
Acraman Creek-Streaky Bay
−
Prime
IUCN
Conservation
Values:
biodiversity, cultural, social values (IUCN II).
IUCN Identification Criteria: naturalness
(not subjected to human-induced change),
biogeographic (geological monuments at Point
Brown, Point Collison, Acraman Creek,
representative habitats), ecological (diversity
of marine habitats, extensive seagrass
meadows of Streaky Bay, samphire
communities at Acraman Creek, threatened
waterbirds – Hooded Plover, White-bellied
Sea Eagle, Osprey, Cape Barren Goose,
Eastern Curlew, ecological integrity),
economic (key nursery areas for Western King
Prawn, marine scalefish fisheries), social
(aboriginal occupation complex at Point
Brown,
Acraman
Creek,
recreation),
national/international (Wetland of National
Importance – Streaky Bay, including Acraman
Creek,
international
importance
for
shorebirds, aboriginal occupation complexes
at Point Brown and Acraman Creek),
practicality
(accessibility,
insulation,
compatibility-adjacent to Acraman Creek
Conservation Park).
Nuyts Archipelago
Prime IUCN Conservation Values: rare and
endangered species/habitats, biodiversity,
aesthetics, scientific research/monitoring
(IUCN Category IB). IUCN Identification
Criteria: naturalness (not subjected to humaninduced change), biogeographic (representative
habitats), ecological (ecological integrity,
diversity of marine habitats, mangroves on St
Peter Island, significant breeding colonies for
Australian Sea Lions – Purdie Rocks, Lounds
Island, West Island, Fenelon Island, NE
Franklin Island, Olive Islands and Jones,
significant breeding colonies for New Zealand
Fur Seals – Fenelon Island, breeding sites for
Short-tailed Shearwaters, Little Penguins-St
Francis Island, St Peter Island, nesting sites for
Ospreys, White-bellied Sea Eagle-St Peter
Island, Bandicoots, Carpet Python, Black Tiger
Snakes), economic (Greenlip and Blacklip
Abalone, Southern Rock Lobster), social
(aesthetic values, aboriginal fish trap-St Peter
Island, tourism, recreation), scientific (scientific
studies at St Francis Isles), national (Register of
the National Estate – Nuyts Archipelago
Conservation Park, St Francis Conservation
Park), practicality (insulation, compatibilityadjacent to Nuyts Archipelago Conservation
Park, Isles of St Francis Conservation Park).
Franklin Islands-Eyre Islands-Cape Missiessy
Eba Island
−
Prime IUCN Conservation Values: cultural
values, biodiversity (IUCN III).
IUCN
Identification Criteria: naturalness (not
subjected
to
human-induced
change),
ecological (extensive seagrass meadows,
sandflats, breeding colony of Silvergulls),
economic (marine scalefish fisheries, key
nursery area for Western King Prawn and
marine scalefish fisheries), social (aboriginal
fish trap-Eba Island, aboriginal occupation site
at Perlubie), national (Register of the National
Estate-Eba Island Conservation Park),
practicality (insulation, compatibility-adjacent
to Eba Island Conservation Park).
−
Prime IUCN Conservation Values: rare and
endangered species/habitats, biodiversity
(IUCN Category IA). IUCN Identification
Criteria: naturalness (not subjected to humaninduced change), biogeographic (geological
monument - Eyre Island, representative
habitats), ecological (mangroves/samphires on
Eyre Island and Cape Missiessy, seagrass
meadows, significant breeding colony of
Australian Sea Lions on NE Franklin Island,
Greater Stick Nest Rats – last remaining
population, Southern Brown Bandicoot, Black
Tiger Snakes), economic (key nursery area for
Western King Prawn, marine scalefish fisheries,
Greenlip and Blacklip Abalone, Southern Rock
Lobster), social (aboriginal fish traps at Point
Dillon-Cape Missiessy), national/international
(Register of the National Estate-Nuyts
Archipelago Conservation Park, Greater Stick
Nest Rats-Franklin Island), practicality
(insulation, compatibility-adjacent to Franklin
Islands Conservation Park, Eyre Islands
Conservation Park).
Page 43
EYRE REGION – STREAKY AND NUYTS BIOUNIT
Olive Islands
−
Prime IUCN Conservation Values: rare and
endangered species/habitats, biodiversity
(IUCN Category IA). IUCN Identification
Criteria: naturalness (not subject to humaninduced change), ecological (significant
breeding colony of rare Australian Sea Lions),
national (Register of the National Estate-Olive
Islands Conservation Park), practicality
(insulation, compatibility-adjacent to Olive
Islands Conservation Park).
Page 44
EYRE REGION - YANERBIE BIOUNIT
V
MARINE BIOGEOGRAPHY AND CONSERVATION VALUES OF THE YANERBIE BIOUNIT
This biounit extends from Cape Bauer to Talia Caves, just south of Venus Bay and covers an area of 82,854 ha.
MARINE BIOGEOGRAPHY
1
An estimated 57% of the average volume of bay is
exchanged each tidal cycle (Bye 1993).
OCEANOGRAPHY
This biounit experiences wave energies ranging from
very low in the coastal embayments (ie. Baird Bay,
Venus Bay, to very high wave swell conditions along
the mainland coast.
Open coast sea temperatures vary from a mean
summer sea surface temperature of 18oC to a mean
winter sea surface temperature of 14oC. The inshore
coastal regions are very productive and are
characterised by seasonal, nutrient-rich, coldwater
upwellings, which can result in an offshore sea
surface temperature gradient of 18oC to 11oC in
inshore areas during the summer months (Wenju et
al. 1990). There appears to be a relationship between
the upwellings and the pilchard numbers in these
areas (Ward & McLeay 1998).
Venus Bay is a shallow semi-enclosed bay linked to
the ocean via a narrow mouth. The depth at the
mouth of the bay is approximately 6m. The main
channel lies to the east of Germein Island. The bay
consists of two almost level basins of about 2.6m and
2.3m depth (Bye 1993). An extensive shallow region
occurs in the south-east of the bay, and a narrower
shallow region along the northern shore. The
restricted access to ocean (the entrance to Venus Bay
is 140m across) imposes a physical barrier to the
advection of King Western Prawn larvae into the
bays (Wallner 1985, Carrick 1993).
High net summer evaporation combined with long
water residence times within the bay produces large
salinity and temperature variability (Wallner 1985).
Salinity increases from the mouth of Venus Bay (at
36 psu) to the shallow inshore regions (which reach
salinities of 40 psu). Notable regions of high salinity
occur in the far southeast, and in the northwest of the
bay (Bye 1993).
2
GEOLOGY
AND
GEOMORPHOLOGY9
COASTAL
The majority of the coast within this biounit
comprises Pleistocene dune calcarenite cliffs
interspersed
with
Holocene
sediments.
Precambrian crystalline rock forms the bedrock of
all major peninsulas, thereby providing the primary
crenulations along the coast, and acting as a
basement for the multiple episodes of Pleistocene
marine - aeolian transgressions. Around the Westall
Peninsula the calcarenite mantles have been wave
eroded to form shore platforms (Twidale et al. 1977).
The shoreline consists of reefs and shore platforms,
as well as beach-surf zone and surf zone.
There are two large coastal embayments within this
biounit (Baird Bay, Venus Bay).
Venus Bay (73 km2) consists of areas of samphire
swamps and mangroves (0.40 km2) together with
intertidal sand/mudflats (14.74 km2). Germain Island
is a large mangrove and samphire swamp built by the
tidal currents in Venus Bay.
3
BIOLOGY
Major Inshore Habitats
−
Major intertidal habitats in the region include
bays and `estuaries’ (ie. saltmarshes,
mudflats), sandy beaches, rocky limestone
shores, and offshore islands.
−
Of the total inshore subtidal habitats mapped
in the biounit (21,977ha), sandy bottoms
comprise 9,573 ha (43.6%), seagrass meadows
comprise 6,602 ha (30.0%), and limestone
reefs comprise 5,802 ha (26.4%).
Venus Bay is a poorly flushed estuary, with an
estimated flushing time of 75 days (Bye 1993). The
flushing mechanism is primarily by tidal currents
flowing in and out of mouth of the bay.
9
From Eyre Coast Protection District Study Report.
Page 45
EYRE REGION - YANERBIE BIOUNIT
Point Labatt near Streaky Bay conserves one
of the largest mainland colony of Australian
Sea Lions (Neophoca cinerea) in Australia
(Gales et al. 1994).
Major Benthic Communities
•
Macroalgal
−
Along the exposed rocky shores and reefs in
this region (eg. Searcy Bay, Point Labatt,
Point Weyland), subtidal rocky shore
macroalgal communities are dominated by the
fucoids,
Cystophora
monoliformis,
C.siliquosa, and C.monolifera and the red
algae, Osmundaria and Haliptilon occur in
shallow waters (ie. 5m). In deeper waters,
rocky reef communities are dominated by
Ecklonia radiata and Acrocarpia paniculata
with Osmundaria prolifera with species of
Cystophora (C.platylobium, C.racemosa,
C.moniliformis) as sub-dominants, and also a
range of large understorey red algae (eg.
Plocamium, Phacelocarpus, Carpophyllis,
Carpopeltis, Peysonnelia, Sonderopelta) and
green algae (Caulerpa flexilis, C.obscura).
•
Seagrass
−
Seagrass communities within the region are
confined to Baird Bay and Venus Bay.
Shallow
water
seagrass
communities,
dominated by Heterozostera tasmanica and
Amphibolis antarctica, occur at the mouth of
Venus Bay.
Within the bay, seagrass
communities dominated by Zostera muelleria,
Posidonia australis and Ruppia occur (see
Figure 2).
−
Numbers of sea lions at the colony have varied
from 14 to 82 between 1966 and 1983
(Robinson & Heard 1985). A more recent
survey recorded 42 sea lions (Gales et al.
1994). Threatened species include the Whitebellied Sea Eagle, Haliaeetus leucogaster
(Sv), Osprey, Pandion haliaetus (Sv). An old
Osprey nest is present on the northern most
headland of the area. The most commonly
seen seabirds include cormorants, gulls and
terns. The park is on the Register of the
National Estate.
−
Baird Bay is a recognised wetland of national
importance (see ANCA 1996). Baird Bay is a
narrow, shallow, sheltered bay that opens into
Anxious Bay. The bay comprises extensive
areas of tidal sand flats, beach ridges and
coastal dunes and provides a drought refuge
and habitat for a wide variety of waterbirds on
the west coast of South Australia (ANCA
1996).
The bay supports the largest
concentration of Grey Plovers, Pluvialis
squatarola on the west coast. The islands in
the bay provide a roosting place for a large
number of seabirds.
Threatened species
include White-bellied Sea-Eagle, Haliaeetus
leucogaster (Sv), Osprey, Pandion haliaetus
(Sv), Fairy Tern, Sterna nereis (Sv). A total
of 19 species of waterbirds have been
recorded, 10 of which are listed under
international treaties (Fuhlbohm 1992). Baird
Bay has been identified as an area of
international importance for shorebirds by
Watkins (1993).
−
Jones Island (Baird Bay Islands Conservation
Park) has a small breeding colony of
Australian Sea Lions on its seaward slopes. A
colony of 33 sea lions was recorded in 1990
(Gales 1990). It is also a known breeding area
for Pelicans (Eckert et al. 1985). The park is
on the Register of the National Estate.
Coastal and Offshore Islands (or Reefs)
−
Venus Bay contains Germain, Garden and
Tank islands, and three other small islands.
MARINE CONSERVATION VALUES
1
SIGNIFICANT
BIOLOGICAL
PHYSICAL FEATURES
AND
1.1 Biological
Coastal and Marine Wetlands of National
Importance
−
Point Labatt is a recognised wetland of
national importance (see ANCA 1996) and
also, the site of the Point Labatt Conservation
Park and Aquatic Reserve.
Page 46
EYRE REGION - YANERBIE BIOUNIT
diversity of it's associated wetlands suggest
that it's contribution to the ecology of the local
area would be significant (Bucher & Saenger
1989). The reefs near the mouth of Venus
Bay support high densities of juvenile Roei
Abalone (Haliotis roei) (D.Mackie, PISA,
pers.comm.).
Other Areas of Conservation Significance
−
Venus Bay Conservation Park (1,460 ha)
consists of Venus Bay Peninsula (Cape
Weyland), Germain, Garden and Tank islands,
and three other small islands. The park has
small breeding populations of Pelicans
(Pelicanus conspicillatus), while one island
has been used as a `halfway house' to
reintroduce
captive-bred
Brush-tailed
Bettongs Bettongia penicillata to St Francis
Island. Colonies of Bettongs also occur on the
Venus Bay peninsula (P.Hone, SARDI,
pers.comm.). The park is on the Register of
the National Estate. Venus Bay is considered
an area of particular natural beauty with a
spectacular view of cliffs from Needle Eye
Lookout.
−
The foreshore areas from east of Venus Bay to
Port Kenny are considered to have some
significance as bird habitat due to the presence
of freshwater soaks. Common bird species in
the area include: Chestnut Teal, Fairy Tern
(rated `vulnerable', both for the State and
region), Greenshank, Pied Oystercatcher, Red
Neck Stint, Sharp-tailed Sandpiper and Sooty
Oystercatcher. The small islands within the
bay support nesting sites for Rock Parrots,
Terns, Silver Gull, Pacific Gull, and also the
Fairy Tern, while island `C' supports
approximately 30 breeding pairs of Pelicans.
The Caspian Tern also breeds on the islands
(Copley 1996). The cliffs of the Venus Bay
Conservation Park contain nests of the Osprey
and White-breasted Sea-eagle.
−
Venus Bay is a popular recreational fishing
locality (Starling 1986), supporting substantial
and diverse areas of wetland that would
provide habitat for estuarine and offshore fish
stocks (Bucher & Saenger 1989).
In
particular, Venus Bay is considered an
important nursery area for King George
Whiting (Sillaginodes punctatus) (Jones
1980). This is because of the close association
of juvenile fish with Zostera and Posidonia
seagrass beds and tidal creeks. Tagging
studies conducted by Jones (1980) in Venus,
Baird and Murat Bays, indicate that fish
tagged in these inshore bays remain in these
bays for up to 2 years (ie. about 32-33cm
length). From Venus Bay, the older fish may
move out of the bay as far as Waldegrave
Island (41km) and St Peter Island (153km)
(Jones 1980). Anectdotal evidence suggests
that the bay may also be a nursery area for
Gummy Shark because of the high numbers of
juveniles caught in the area (D.Mackie, PISA,
pers.comm.). Venus Bay is also a significant
nursery area for Australian Salmon (Cappo
1987). The size of the bay and the extent and
−
Venus Bay is also a significant nursery area
for the Western King Prawn (Penaeus
latisulcatus) (King 1977, Wallner 1985,
Carrick 1993). Venus Bay represents the most
significant nursery area for P.latisulcatus for
the west coast prawn fishery. As such, it
represents the principal nursery area for the
Venus Bay trawl grounds, which contribute
approximately 70% of the west coast prawn
catch (Carrick 1993). The Venus Bay trawl
grounds extend approximately 10 nautical
miles offshore and cover an area of
approximately 100 square nautical miles. A
feature unique in South Australia, is the role
of Venus Bay as a nursery area for both,
juvenile
and
sub-adult
P.latisulcatus
(N.Carrick, SARDI, pers.comm.). Juvenile
prawns occupy the intertidal regions of the
bay, with subadults moving into the deeper
parts of the bay.
Juveniles of Western King Prawn are found in
several shallow bays and tidal creeks in the
Elliston-Venus Bay. The waters of these
nursery areas are hypersaline, have high
summer temperatures and invariably contain
seagrass communities (mainly Posidonia
australis); many, but not all, are associated with
stands of mangroves (Avicennia marina) (King
1979). The substrate in these nursery areas
varies from silty to clean sand with some shell
grit. Substrates of soft mud or large quantities
of shell grit appear not be preferred by juvenile
Western King Prawn. Juvenile prawns utilise
only areas of shallow, bare sand substrate
(Wallner 1985).
−
Venus Bay consists of areas of samphire
swamps and mangroves (0.40 km2) together
with intertidal sand/mudflats (14.74 km2)
(Bucher & Saenger 1989). Germain Island is
a large mangrove and samphire swamp built
by the tidal currents in Venus Bay. Avicennia
marina on the south-eastern flank of Germein
Island was recorded by Butler et al. (1975).
Venus Bay has extensive areas of Zostera
seagrass beds, particularly by the Venus Bay
caravan park and also, in the north of the bay.
The seagrass, Ruppia is also found in the far
northern end of bay.
Page 47
EYRE REGION - YANERBIE BIOUNIT
Razorfish (Pinna sp.) used to occur near the
Port Kenny jetty and in the western end of
Venus Bay (D.Mackie, PISA, pers.comm.).
1.2 Physical
−
Geological Monuments
None.
2
OTHER VALUES
2.1 Commercial Fisheries
Major single species fisheries in this region include
Western King Prawn, Abalone and Southern Rock
Lobster. There is also a considerable marine
scalefish fishery targeting mainly King George
Whiting by hand line. Some netting occurs inside
parts of Venus Bay. Some of the Southern Bluefin
Tuna boats use Thevenard as their major port of
landing.
Major single species fisheries in Venus Bay include
Western King Prawn and Abalone (at the mouth of
Venus Bay). There is also a considerable marine
scalefish fishery targeting mainly King George
Whiting by hand line. There are 5 licensed netters
and 10 licensed hookers who work Venus Bay, plus a
number of part-timer operators (T.Whibley,
pers.comm.).
Southern Rock Lobster
This biounit represents a significant region for
lobster fishing in South Australia. In 1995/96 and
1996/97 a total of 41 and 34 licensed operators
fished in the Anxious Bay and inshore Investigator
Group region (ie. Fishing Zone 15), catching
approximately 168,235 and 161,534 kg of lobsters,
respectively (or 3.23% and 3.16% of the total catch
for Southern Rock Lobster in South Australian
waters).
Abalone
The Blacklip Abalone and Greenlip Abalone is a
significant fishery within the Yanerbie Biounit. In
1994/95 and 1995/96 a total of 30,222 and 33,657
kg of Greenlip was harvested within this region (ie.
MapCode 4A-H, 5A-F, 6A-D, Point Westall to
Venus Bay), and represented 13.3% and 14.9% of
the total Greenlip Western Zone catch (or 8.02%
and 8.99% of the total catch for Greenlip in South
Australian waters). In 1994/95 and 1995/96 a total
of 76707 and 77,934 kg of Blacklip was harvested
within this region, and represented 24.7% and
28.0% of the total Blacklip Western Zone catch (or
15.52% and 16.83% of the total catch for Blacklip
in South Australian waters).
Marine Scalefish Fisheries
During 1995/96 and 1996/97, 42 and 44
commercial licence holders (made up of Marine
Scalefish, Restricted Marine Scalefish and
Northern Zone Rock Lobster licence categories)
caught commercial marine scalefish species from
Baird Bay and Venus Bay (ie. Fishing Zones 16
and 17), respectively. License holders expended
approximately 2980 and 2,583 boat days effort
fishing these waters during 1995/96 and 1996/97,
respectively. The marine scalefish catch for this
region (ie. Fishing Zones 16 and 17) represented 78
928 kg in 1995/96 and 80 568 kg in 1996/97(or
0.76% and 0.79% of the total catch for the marine
scalefish fishery in South Australian waters).
Outside of Baird Bay and Venus Bay, during
1995/96 and 1996/97, 21 and 34 commercial
licence holders (made up of Marine Scalefish,
Restricted Marine Scalefish and Northern Zone
Rock Lobster licence categories) caught
commercial marine scalefish species from the
Anxious Bay and inshore Investigator Group
region (ie. Fishing Zone 15), respectively. License
holders expended approximately 570 and 899 boat
days effort fishing these waters during 1995/96 and
1996/97, respectively. The marine scalefish catch
for this region (ie. Fishing Zone 15) represented
133 221 kg in 1995/96 and 283 665 kg in
1996/97(or 1.28% and 2.79% of the total catch for
the marine scalefish fishery in South Australian
waters).
2.2 Aquaculture
Current aquaculture in this region is centred on
Waterloo Bay (Elliston) and the southern end of
Anxious Bay. The only oyster lease to be developed
in Venus Bay and the few other attempts at growing
oysters in the bay have all failed to demonstrate the
economic viability of Pacific Oyster farming (GroveJones 1986, Hone 1993). The Elliston Aquaculture
Management Plan (Ashman 1996) recommended the
following aquaculture development in the region:
Venus Bay Policy Area
−
Port Kenny Zone (waters of eastern side of
bay, from Port Kenny to Germein Island to
Venus Bay township) – zoned for aquaculture
development of native species. Licenses will
be considered for a maximum of 30ha of
aquaculture development within this zone,
excluding Pacific Oyster culture and species
which require supplementary feeding.
Page 48
EYRE REGION - YANERBIE BIOUNIT
−
Venus Bay Zone (remaining waters of Venus
Bay) – zoned to protect and maintain existing
values and uses. Licenses will not considered
for aquaculture development within this zone.
−
Elliston Policy Area
Elliston Zone (all waters of the Elliston Policy
Area, from mouth of Venus to south of Sheringa
Beach, excluding Venus Bay, but including Cap
Island, Waldegrave Islands and The Watchers) –
zoned to provide for aquaculture development.
Licenses will be considered for a maximum of
60ha of aquaculture development within this zone,
but not within Waterloo Bay and 1km of
Waldegrave Islands, Cap Island, Lake Newland,
Talia Caves and Venus Bay Conservation Parks.
2.3 Recreation and Tourism
Agriculture/Industry
−
Recreational boat, jetty, rocks and beach
fishing include King George Whiting, Sand
Flathead, Yelloweye Mullet, Australian
Salmon, Snook, Sweep, Garfish and
Greenback Flounder as major species.
−
−
SCUBA diving: Smooth Pool (south of
Streaky Bay) is a recognised dive spot and
listed in `Dive South Australia: The Best Dive
Sites in South Australia (Diving Industry
Association of South Australia). The dive is a
ideal shallow, sheltered dive suitable for
novice divers.
2.4 Scientific Research and Education
−
Significant scientific research and monitoring
studies has been conducted by SARDI into the
recruitment of Western King Prawn (Penaeus
latisulcatus) in Venus Bay (Carrick 1993).
2.5 Adjacent Land Use
National and Conservation Parks
−
Sceale Bay Conservation Reserve (485 ha).
−
Point Labatt Conservation Park (39 ha):
adjoins the Point Labatt Aquatic Reserve (no
access is permitted within 1 nautical mile)
(DELM 1993).
−
Baird Bay Islands Conservation Park (24 ha),
including Jones Island and an unnamed island
at the head of the bay.
Venus Bay.
Port Kenny.
2.6 Significant Cultural and Historical Values
Aboriginal
−
Tourism
−
Sealed and unsealed roads provide access to
the shore. Jetties are located at Port Kenny
and Venus Bay.
Urban Centres
Fishing
−
Venus Bay Conservation Park (1423 ha):
consists of Venus Bay Peninsula (Cape
Weyland), Germein Island and five other
small islands in Venus Bay (Garden, Tank, A,
B, C).
−
3
The Venus Bay region has significant
Aboriginal value. Nicholson (1991), in a
survey of cultural sites in the area, identified
seven occupation sites in Venus Bay.
Nicholson (1991) descibed the area as an
occupation site complex, consisting of seven
open coastal campsites, one midden and an
artefact or stone scatter. waterhole
European
Not known.
CURRENT CONSERVATION STATUS
OF THE YANERBIE BIOUNIT
−
Marine Reserves
None
−
Marine Parks
None
−
Netting Closures
Baird Bay (all waters of Baird Bay).
−
Venus Bay (all waters of the eastern section of
Venus Bay situated east of a straight line
extending southerly across Venus Bay from
the most westerly corner of section 72
hundred of Wright to the Trigonometrical
Station on Point Weyland).
Page 49
EYRE REGION - YANERBIE BIOUNIT
4
AREAS OF HIGH CONSERVATION IN
THE YANERBIE BIOUNIT
Sceale Bay-Smooth Pool
−
Prime
IUCN
Conservation
Values:
biodiversity, social values (IUCN Category
IA).
IUCN Identification Criteria:
naturalness (not subject to human-induced
change), biogeographic (representative marine
habitats), ecological (diversity of habitats, reefs,
sand habitats), economic (major Blacklip
Abalone fishing grounds), social (diving at
Smooth Pool, scenic amenities), scientific
(scientific monitoring), national/international,
practicality (compatibility-adjacent to Sceale
Bay Conservation Reserve).
Caspian Tern, Osprey, White-breasted Sea
Eagle, Silver Gull, Pacific Gull, Brush-tailed
Bettongs, ecological integrity), economic
(Western King Prawn, marine scalefish
fisheries,
tourism),
social
(aboriginal
occupation site complex, scenic amenities,
recreation), scientific (scientific monitoringWestern King Prawn), national (Register of the
National Estate-Venus Bay Conservation Park,
recognised estuary and wetland of importance),
practicality
(insulation,
accessibility,
compatibility-adjacent
to
Venus
Bay
Conservation Park and Conservation Reserve).
Point Labatt-Baird Bay (and islands)
−
Prime IUCN Conservation Values: rare and
endangered species/habitats, biodiversity
(IUCN Category IA). IUCN Identification
Criteria: naturalness (not subject to humaninduced
change,),
biogeographic
(representative habitats), ecological (diversity
of marine habitats, mangroves, seagrasses,
wetland habitats, significant breeding colony
of Australian Sea Lions at Point Labatt and
Jones Island, nursery function, marine and
wetland habitats, breeding population of
Australian Pelicans-Jones Island, threatened
waterbirds-Grey Plovers, White-bellied Sea
Eagle, Osprey, Fairy Tern, ecological
integrity), economic ((major Blacklip Abalone
fishing grounds, Western King Prawn,
scalefish
fisheries,
tourism),
social
(recreation, tourism, scenic amenities),
scientific (scientific monitoring), national
(international importance for shorebirdsBaird Bay, Wetland of National ImportancePoint Labatt, Baird Bay, Jones Island,
Register of the National Estate-Point Labatt,
Jones Island), practicality (accessibility,
insulation, compatibility-adjacent to Baird
Bay Islands Conservation Park).
Venus Bay Conservation Park
−
Prime IUCN Conservation Values: rare and
endangered species/habitats, biodiversity,
aesthetics, social values (IUCN Category II).
IUCN Identification Criteria: naturalness (not
subject
to
human-induced
change),
biogeographic (representative marine habitats),
ecological (diversity of marine habitats,
mangroves, seagrasses, wetland habitats, key
nursery function-Western King Prawn,
scalefish, marine and wetland habitats,
breeding population of Australian PelicansIsland C, seabirds-Rock Parrots, Fairy Tern,
Page 50
EYRE REGION – SHERINGA AND FLINDERS BIOUNITS
VI
MARINE BIOGEOGRAPHY AND CONSERVATION VALUES OF THE
NEWLAND BIOUNIT
This small biounit extends from Talia Caves to Cape Finniss on the Eyre Peninsula and covers an area of 45,238 ha
and a coastal distance of 38 km. It faces southwesterly into the Great Australian Bight.
MARINE BIOGEOGRAPHY
1
OCEANOGRAPHY
This biounit experiences wave energies ranging from
low near Cape Finniss and in Waterloo Bay, to high
around the offshore islands, cliffs and some sections
of the mainland coast.
Open coast sea temperatures vary from a mean
summer sea surface temperature of 18oC to a mean
winter sea surface temperture of 14oC. The inshore
coastal regions are very productive and are
influenced by seasonal, nutrient-rich, coldwater
upwellings (Wenju et al. 1990), which can result in
an offshore sea surface temperature gradient of 18oC
(in the Pearson Isles) to 11oC (off Waldegrave
Islands) during the summer months.
2
GEOLOGY
AND
GEOMORPHOLOGY10
COASTAL
This biounit is distinct because it is a continuous
Holocene barrier bounded at either end by the
extensive dune calcarenite cliffs of the Yanerbie
Biounit and the Sheringa Biounit. Between Cape
Finniss and Walkers Rocks, the 8km of shoreline is
low-energy, with reflective beaches backed by up to
1km of Holocene dune transgression. The main
barrier from Walkers Rock to Talia Monument is 26
km long and largely overlies Pleistocene deposits.
Long Pleiocene reefs run parallel to the shore,
approximately 1 km offshore.
The whole barrier is backed by saline 20 km long
Lake Newland which occupies the back barrier
depression. The lake has been partially transgressed
by the dunes throughout its length. In the southern
half, past and present dune transgression has nearly
filled the lake, reaching the eastern shore in places.
The entire biounit is very dynamic and unstable
(subject to both beach and dune instability).
10
There are two groups of offshore islands in the
biounit: the Waldegrave Islands and The Watchers.
Waldegrave Island is the largest of this group and
consists of a crystalline basement (covered by
calcareous aeolianite of varying thickness), which
outcrops at the base of the island. Small sandy bays
occur on the island, the largest on the northern side.
A smaller island occurs to the west of Waldegrave
Island and is similar, except there are no small
beaches or inlets. The Watchers are two isolated
outcrops of crystalline rocks.
3
BIOLOGY
Major Inshore Habitats
−
Major intertidal habitats in the region include
sandy beaches, limestone rocky shores, and
offshore islands.
−
Of the total inshore subtidal habitats mapped
in the biounit (7,549ha), sandy bottoms
comprise 4,318ha (57.2%), and limestone
reefs comprise 3,231 (42.8%). No seagrass
meadows have been mapped in the region.
Major Benthic Communities
•
Macroalgal
−
At Anxious Bay, subtidal offshore rocky reef
macroalgal communities (at 15m) dominated
by the fucoids, Cystophora monoliformis,
C.platylobium, and Ecklonia radiata and the
red algae, Osmundaria, Phacelocarpus and
Plocamium costatum.
In the shallow,
sheltered areas of Waldegrave Island (ie. 510m), the subtidal rocky shores are dominated
by the fucoids, Cystophora monoliformis,
C.pectinata, and C.monolifera and the red
algae, Osmundaria, and species of Caulerpa
(C.flexilis and C.cactoides). In Waterloo Bay,
rocky areas are dominated by species of
Cystophora, Ecklonia radiata and Scaberia
agardhii (Shepherd & Womersley 1981).
From Eyre Coast Protection District Study Report.
Page 51
EYRE REGION – SHERINGA AND FLINDERS BIOUNITS
•
Seagrass
−
At Waldegrave Island, deeper water seagrass
communities dominated by Posidonia and
Halophila occur.
Within Waterloo Bay,
seagrass communities occur dominated by
Heterozostera
tasmanica,
Amphibolus
antarctica and species of Posidonia
(P.sinuosa, P.angustifolia, P.australis and
P.ostenfeldii) (Shepherd & Womersley 1981).
Fish species in the coastal lake include the
Small-mouthed Hardyhead, Atherinosoma
microstoma.
Lake Newland Conservation
Park: in a state-wide survey of wetlands
conducted by Lloyd and Balla (1986), Lake
Newland was considered to be an area of
outstanding environmental value.
Other Areas of Conservation Significance
−
Coastal and Offshore Islands (or Reefs)
−
Waldegrave Islands.
−
The Watchers.
MARINE CONSERVATION VALUES
1
SIGNIFICANT
BIOLOGICAL
PHYSICAL FEATURES
AND
1.1 Biological
Peak catches occur during the winter months,
primarily due to calmer weather enabling more
fishing nights. Adults prawns spawn on the
trawl grounds during the summer months, with
a concentration of ripe females located inshore.
Prawns move out in a southerly direction in
Anxious Bay (from the entrance to Venus Bay)
along the 30m contour, dispersing into the
deeper waters of the Venus Bay trawl grounds
(Wallner 1985).
Coastal and Marine Wetlands of National
Importance
−
Lake Newland has been identified as a
wetland of national importance (see ANCA
1996).
Lake Newland is a relatively
permanent salt lake with freshwater springs,
which is fed by seasonally by freshwater
surface and groundwater sources, marine
seepages and by occasional direct marine
incursion. Lake Newland has been identified
as an area of international importance for
shorebirds by Watkins (1993). Lake Newland
is one of the few permanent saltlakes located
near the coast on Eyre Peninsula. The lake is
the largest and supports a variety of wetland
wildlife and serves as a drought refuge for
numerous waterbirds and is a significant
Hooded Plover, Thinornis rubricollis summer
feeding habitat. Lake Newland also holds
significant populations of several threatened
species, including the Hooded Plover (Nv,
Sv), Cape Barren Goose, Cereopsis
novaehollandiae (Sv), Fairy Tern, Sterna
nereis (Sv), Eastern Reef Egret, Egretta sacra
(Sr), and the Peregrine Falcon (Fuhlbohm
1991). Cape Barren Geese (350 recorded)
arrive in late spring, summer and autumn from
nearby Waldegrave Island to feed. At least 34
species of waterbird have been recorded, 5
listed under international treaties. It can be
assumed that the adjoining coastline is equally
important.
Anxious Bay produces approximately 80% of
the west coast prawn catch for South Australia
(Wallner 1985). The trawl grounds extend
approximately 10 nautical miles offshore from
Venus Bay and cover an area of
approximately 100 square nautical miles
(Carrick 1993). Larval P.latisulcatus migrate
from the offshore spawning areas in Anxious
Bay to the primary nursery area at Venus Bay
(Wallner 1985). Baird Bay is of lesser
importance as a nursery habitat because of the
very high summer salinities (in excess of 60
ppt), with prawns restricted to the southern
half of the bay (Wallner 1985).
−
Waldegrave Islands Conservation Park: these
islands have a spectacular coastline of cliffs
and sandy beaches, and also represent the
second most important breeding area for Cape
Barren Geese in South Australia. The birds
that breed on Waldegrave Island stay in the
Elliston area for the summer, feeding in
swamps around the margins of Lake Newland
and on grain in wheat paddocks. They roost
on the beach or fly back to the island for the
night.
It is important for the overall
conservation of this species in South Australia
that this apparently separate population is
disturbed as little as possible (Robinson &
Heard 1985). Goose Island is an important
Cape
Barren
Goose
breeding
area
(T.Fulbohm, NPWS, pers.comm.). Breeding
colonies of the Little Penguin are common on
Little Waldegrave Island, while 300 pairs have
been recorded on Waldegrave Island (Copley
1996).
Page 52
EYRE REGION – SHERINGA AND FLINDERS BIOUNITS
−
A small colony of Australian Sea Lions (38)
have been recorded on West Waldegrave
Island and are possibly breeding here.
(Gales 1990). The islands are on the Register
of the National Estate.
1.2 Physical
Geological Monuments
−
Talia Caves is of State significance: the
landforms developed in this area, particularly
the caves and the mobile dune field, are
spectacular.
The region is an unspoilt
wilderness.
2
OTHER VALUES
2.1 Commercial Fisheries
Major single species fisheries in this region include
Greenlip and Blacklip Abalone and Southern Rock
Lobster. There is also a considerable marine
scalefish fishery targeting mainly King George
Whiting by hand-line.
Abalone
The Western Zone for commercial abalone fishery is
all those waters west of the latitude 136o30' east and
includes all the waters of the management plan.
There are 23 license holders in this zone.
The Blacklip Abalone and Greenlip Abalone is a
significant fishery within the Newland Biounit. In
1994/95 and 1995/96 a total of 15,327 and 1,9119
kg of Greenlip was harvested within this region (ie.
MapCode 6E, 7A-B, 8A-E, 8Q, Anxious Bay,
Waldegrave Island, The Watchers), and represented
6.7% and 8.5% of the total Greenlip Western Zone
catch (or 4.07% and 5.11% of the total catch for
Greenlip in South Australian waters). In 1994/95
and 1995/96 a total of 20,556 and 17,217 kg of
Blacklip was harvested within this region, and
represented 6.6% and 6.2% of the total Blacklip
Western Zone catch (or 4.16% and 3.72% of the
total catch for Blacklip in South Australian waters).
The `Hot Spot' near Ward Island and Waterloo Bay
are very productive sites for commercial abalone
harvesting. Elsewhere, abalone reefs are scattered
throughout Anxious Bay, the offshore islands, the
Elliston Cliffs (where abalone are found in the top 2
metres down to 20-25 metres, where it ends in sandy
bottom), and the mouth of Venus Bay (S.Shepherd,
SARDI, pers.comm.).
There are 4 abalone divers for 4 licenses in the
Elliston region. In addition, a further 19 divers work
the waters off Elliston, occasionally diving in
Waterloo Bay, but most commonly working off
Anxious Bay and out to the offshore islands
(T.Whibey, pers.comm). Blacklip Abalone are taken
on calm seas from the shallower waters, while
Greenlip Abalone are taken from the deeper water
when there is a swell.
Western King Prawn
This biounit is located within the waters of the West
Coast prawn fishery, which comprises 3 license
holders (ie. Boats). All vessels fish within the waters
of this biounit (ie. Fishing Zones 15), the Nuyts
Biounit (ie. Fishing Zone 8) and the Douglas Biounit
(ie. Fishing Zone 27). In 1995/96 and 1996/97 a total
of 200,764 and 166,414 kg was caught for this
fishery, with a total effort of 3,144 and 2,778 hours,
respectively (or 8.84% and 8.22% of the total catch
for Western King Prawn in South Australian
waters).
Marine Scalefish
Outside of Baird Bay and Venus Bay, during
1995/96 and 1996/97, 21 and 34 commercial
licence holders (made up of Marine Scalefish,
Restricted Marine Scalefish and Northern Zone
Rock Lobster licence categories) caught
commercial marine scalefish species from the
Anxious Bay and inshore Investigator Group
region (ie. Fishing Zone 15), respectively. License
holders expended approximately 570 and 899 boat
days effort fishing these waters during 1995/96 and
1996/97, respectively. The marine scalefish catch
for this region (ie. Fishing Zone 15) represented
133,221 kg in 1995/96 and 283,665 kg in
1996/97(or 1.28% and 2.79% of the total catch for
the marine scalefish fishery in South Australian
waters).
There are 5 marine scalefish licenses in Elliston,
comprising 3 A class and 2 B class fishing licenses.
Operators fish mainly in the vicinity of Anixous Bay,
Waldegrave Island and Flinders Island (T.Whibley,
pers.comm.).
Southern Rock Lobster
This biounit represents a significant region for
lobster fishing in South Australia. In 1995/96 and
1996/97 a total of 41 and 34 licensed operators
fished in the Anxious Bay and inshore Investigator
Group region (ie. Fishing Zone 15), catching
approximately 168,235 and 161,534 kg of lobsters,
respectively (or 3.23% and 3.16% of the total catch
for Southern Rock Lobster in South Australian
waters).
Page 53
EYRE REGION – SHERINGA AND FLINDERS BIOUNITS
One lobster boat works from Elliston as far north as
Talia Caves, south to Tungketta Reef and out to
Flinders Island. In addition, another two or so boats
come from Port Lincoln to work the grounds
(T.Whibley, pers.comm.).
2.4 Scientific Research and Education
−
Beach litter surveys. Anxious Bay is the site
of the longest and only regular survey of
marine (or ship-based) litter in Australia (see
Wace 1995). The survey is a communitybased survey of beach litter, which is
coordinated by the SA Research and
Development Institute and undertaken with
the assistance of staff and students from the
Streaky Bay Area School, Elliston Primary
School and the Cavan Centre for Juvenile
Detention.
−
Researchers from the SA NPWS regularly
conduct ornithological surveys of the region,
particularly for Cape Barren Geese.
−
Fisheries research in this area includes, regular
catch and effort monitoring of the major
commercial fisheries in the region (Abalone,
Southern Rock Lobster, Western King Prawn,
and marine scalefish); regular research and
monitoring of larval fish stocks; regular
research and monitoring of Blacklip and
Greenlip Abalone field stocks; and regular
research and monitoring of South Rock
Lobster field stocks.
Other
There is one licensed shell collector in the Anxious
Bay region (T.Whibley, pers.comm.).
2.2 Mariculture
Current aquaculture in this region is centred on
Waterloo Bay (Elliston) and the southern end of
Anxious Bay. The Elliston Aquaculture Management
Plan (Ashman 1996) recommended the following
aquaculture development in the region:
Elliston Policy Area
−
Elliston Zone (all waters of the Elliston Policy
Area, from mouth of Venus to south of
Sheringa Beach, excluding Venus Bay, but
including Cap Island, Waldegrave Islands and
The Watchers) – zoned to provide for
aquaculture development. Licenses will be
considered for a maximum of 60ha of
aquaculture development within this zone, but
not within Waterloo Bay and 1km of
Waldegrave Islands, Cap Island, Lake
Newland, Talia Caves and Venus Bay
Conservation Parks.
2.3 Recreation and Tourism
−
Talia Caves and beach have great aesthetic
appeal because of their natural, pristine state.
−
Walker's Rock is a focal point for camping
and picnicking activities in the area.
−
SCUBA diving: Waldegrave Island and Little
Waldegrave (north of Elliston) is a recognised
dive spot and listed in `Dive South Australia:
The Best Dive Sites in South Australia (Diving
Industry Association of South Australia’).
The reefs which drop down to 24m are
honeycombed with holes, ledges, caves and
walls and are the home of sponges, ascidians,
gorgonians, crinoids and soft corals. Many
types of fish are recorded here including Blue
Devils, Red-banded Sea Perch and Scaly Fins.
Sea Lions inhabit the north western side of
Little Waldegrave.
2.5 Adjacent Land Use
National and Conservation Parks
−
Lake Newland Conservation Park (8,448 ha).
−
Waldegrave Islands Conservation Park (434
ha).
Agriculture/Industry
−
There is no significant development along this
biounit, and very limited access. Road access
to a boat ramp one kilometre north of Cape
Finniss and to Walkers Rocks. Along the
remaining section of coast, several 4WD
tracks exist, but access along these is difficult.
Urban Centres
−
None.
Page 54
EYRE REGION – SHERINGA AND FLINDERS BIOUNITS
2.6 Significant Cultural and Historical Features
−
−
3
Aboriginal
Newland Barrier, south of Talia Caves: an
occupation site consisting of an artefact
manufacturing site (Nicholson 1991).
European
None.
CURRENT CONSERVATION STATUS
OF THE NEWLAND BIOUNIT
−
Marine Reserves
None
−
Marine Parks
None
−
Netting Closures
None
4
The Watchers Conservation Park
−
Waldegrave
Islands
Prime IUCN Conservation Values: rare and
endangered species/habitats, biodiversity,
research (IUCN Category IA).
IUCN
Identification Criteria: naturalness (not subject
to human-induced change), biogeographic
(representative marine habitats), ecological
(breeding colonies of Cape Barren Goose, Little
Penguin, nesting site for Ospreys, breeding site
for Australian Sea Lion), economic (Blacklip
Abalone, Greenlip Abalone, Southern Rock
Lobster, marine scalefish fisheries, tourism),
social (scenic amenities, SCUBA diving,
recreation), scientific (scientific monitoringCape Barren Goose), national (Register of the
National
Estate-Waldegrave
Islands
Conservation Park), practicality (insulation,
compatibility-adjacent to Waldegrave Islands
Conservation Park).
AREAS OF HIGH CONSERVATION
VALUE IN THE NEWLAND BIOUNIT
Talia Caves - Lake Newland Conservation
Park
−
Prime IUCN Conservation Values: rare and
endangered species/habitats, biodiversity,
cultural, aesthetics, research (IUCN Category
II). IUCN Identification Criteria: naturalness
(not subject to human-induced change),
biogeographic (Talia Caves-unique geology,
representative marine habitats), ecological
(reef, sand habitats, wetland habitats,
threatened birds-Hooded Plover, Cape Barren
Goose, Fairy Tern, Eastern Reef Egret,
Peregrine Falcon, ecological integrity),
economic (Blacklip Abalone, Greenlip Abalone,
Southern Rock Lobster, marine scalefish
fisheries,
tourism),
social
(aboriginal
occupation site, recreation, scenic amenities),
scientific (scientific monitoring-beach litter
surveys), international/national (international
importance for shorebirds and Wetland of
National
Importance-Lake
Newland
Conservation Park), practicality (insulation,
accessibility, compatibility-adjacent to Lake
Newland Conservation Park).
Page 55
EYRE REGION – SHERINGA AND FLINDERS BIOUNITS
VII MARINE BIOGEOGRAPHY AND CONSERVATION VALUES OF THE
SHERINGA AND FLINDERS BIOUNITS
This coastal region comprises 2 biounits: the inshore coastal Sheringa Biounit, and the offshore Flinders Biounit,
which is defined by the 50 metre bathymetric contour. The Sheringa Biounit extends from Cape Finniss to
Drummond Point on the Eyre Peninsula and covers an area of 51,156 ha and a coastal distance of 81 km. The
Flinders Biounit encompasses the Investigator Group and covers an area of 125,957 ha. The region faces
southwesterly into the Great Australian Bight.
MARINE BIOGEOGRAPHY
1
OCEANOGRAPHY
This biounit experiences wave energies ranging
from low in Waterloo Bay, to very high around the
offshore islands and some sections of the mainland
coast.
Open coast sea temperatures vary from a mean
summer sea surface temperature of 18oC to a mean
winter sea surface temperture of 14oC. The inshore
coastal regions are under the influence of seasonal
coldwater, nutrient-rich coastal upwellings which
occur close to the coast, which can result in an
offshore sea surface temperature gradient of 18oC
(eg. in the Pearson Isles) to 11oC (eg. off Waldegrave
Islands) during the summer months. The major focus
of the coastal upwelling appears to extend from the
Coffin Bay Peninsula to Cape Borda (Kangaroo
Island) (Wenju et al. 1990) and in part, may be
responsible for the very high levels of productivity
and marine benthic biodiversity in the region. Recent
studies indicate that is a relationship between the
upwellings and the pilchard abundance in these areas
(Ward & McLeay 1998).
2
GEOLOGY
AND
GEOMORPHOLOGY11
This Flinders Biounit contains a number of offshore
islands. The most well known and most studied, is
the Investigator Group of islands. These islands are
true `inselbergs' (island mountains), and include:
−
Flinders Island is a low mass of granite, with
boulders on its flanks, but capped by
limestone. Small sandy bays and inlets occur
between basement headlands and on the
northern coast two lakes are separated from
the sea by a narrow strip of coastal dunes.
−
Pearsons Islands are high granite islands rising
abruptly 240m from the eastern section of the
Great Australian Bight. They take the form of
domes which are rounded and boulder strewn
on the upper slopes, with massive curvilinear
sheets on the lower levels. Flared slopes and
tafoni are well developed. The western
exposed shores are strongly cliffed.
−
Topgallant Islands consists of one main island
and a number of smaller islands. The smaller
islands appear to be entirely basement. The
larger island has a thick cover of calcareous
aeolianite with extremely steep sides. Beach
sand has been deposited in one small inlet.
−
Ward Island and Cap Island (together with the
nearby reefs and inlets), are crystalline
basement, with thin covers of calcareous
aeolianite.
COASTAL
The Sheringa Biounit consists of an almost straight
section of Pleistocene dune calcarenite cliffs
averaging 40-50 m high at the shoreline and climbing
to over 100 m along much of the coast. The cliffs are
breached only by two relatively small bays (Sheringa
and Waterloo Bay). At Point Drummond the
calcarenite mantles have been wave eroded to form
shore platforms (Twidale et al. 1977). The shoreline
consists of reefs and shore platforms, as well as
beach-surf zone and surf zone.
11
Holocene barrier dune transgression occurs at
Sheringa and a single foredune barrier within
Waterloo Bay occurs where the Pleistocene dune
calcarenite has been completely breached. However,
wave refraction into Waterloo Bay and attenuation
over shallow reefs which block much of the entrance,
has produced low waves at the shoreline.
Consequently, unlike the higher energy Sheringa, the
low wave conditions in the bay have resulted in a low
energy reflective beach backed by a single
moderately stable foredune barrier.
From the Eyre Coast Protection Distric Study Report.
Page 56
EYRE REGION – SHERINGA AND FLINDERS BIOUNITS
3
BIOLOGY
Major Inshore Habitats
−
−
Major intertidal habitats in the region include
mostly rocky limestone shores, offshore
islands, and some sandy beaches.
Of the total inshore subtidal habitats mapped
in the Sheringa Biounit (4,894 ha), limestone
reefs comprise 4,605 ha (94.1%), sandy
bottoms comprise 224 ha (4.6%), and seagrass
meadows comprise 65 ha (1.3%). Of the total
inshore subtidal habitats mapped in the
Flinders Biounit (4,194 ha), limestone reefs
comprise 4,194 ha (100%) of the habitats
mapped. No significant areas of seagrass were
mapped.
MARINE CONSERVATION VALUES
1
Macroalgal
−
At Ward Island, subtidal offshore rocky reef
macroalgal communities dominated by species
of
Cystophora
(C.
monoliformis,
C.monolifera, C.siliquosa, and C.pectinata),
and Ecklonia radiata and species of Caulerpa
(C.flexilis, C.longifolia), articulated corallines
and the red algae, Plocamium costatum. At
Pearson Island, on exposed subtidal rocky
shores, Cystophora is replaced by the
Acrocarpia paniculata, and Homeostrichus.
−
Macroalgal communities at Topgallant Island,
Hotspot, Ward Island are similar to Pearson
Island (Branden et al. 1986).
•
Seagrass
−
At Pearson Island and Ward Island, deepwater
(20-30m) communities of seagrasses occur,
dominated by Heterozostera tasmanica,
Halophila, Amphibolis and Posidonia
australis.
Coastal and Offshore Islands (or Reefs)
Coastal and Marine Wetlands of National
Importance
−
Lake Hamilton has been identified as a
wetland of national importance (see ANCA
1996). Lake Hamilton is a coastal gypsum
lake separated from the ocean by steep cliffs.
The lake and environs contains an excellent
range of habitat types which could be
important for bird breeding. There is no
recognised threatened fauna or flora within the
region. However, threatened waterbirds in the
area include possibly the Hooded Plover,
Thinornis rubricollis (Nv, Sv) on beaches, and
Osprey, Pandion haliaetus (Sv). Lake
Hamilton was considered by Lloyd and Balla
(1986) to be an area of outstanding
environmental value, which recommended
that the area be given status as a wetland
reserve.
−
Sheringa Lagoon was considered by Lloyd
and Balla (1986) to be an area of outstanding
environmental value, which recommended
that the area be given status as a wetland
reserve.
Inshore Islands of Conservation Value
−
Cap Island Conservation Park. The fauna of
this island is typically oceanic. It has a small
breeding colony of the White-faced Storm
Petrel (325 pairs) (Copley 1996) and the
westernmost record of the White-fronted Tern
(Sterna striata) in South Australia. The island
is on the Register of the National Estate.
Offshore Islands of Conservation Value
−
The Investigator Group of Islands (including
Flinders Island, Pearsons Islands, Topgallant
Islands and Ward Islands). Pearson Island has
been the site of a number of major scientific
research investigations. The subtidal flora is
characterised by a high species diversity and
an abundance of algae, while the island itself
is in a relatively pristine state, because of its
unsuitability for farming or grazing sheep (due
to the lack of permanent fresh water). There is
a colony of Pearson Island Rock Wallabies
(Petrogale pearsoni) on the island.
−
A total of 41 species of birds have been
recorded on Pearson Island, of which half are
The Investigator Group of Islands comprising
Flinders Island, Pearsons Islands (Pearson, North
Veteran, South Veteran, Dorothee), Topgallant
Islands and Ward Islands.
−
−
AND
1.1 Biological
Major Benthic Communities
•
SIGNIFICANT
BIOLOGICAL
PHYSICAL FEATURES
Cap Island (offshore from Sheringa).
Tungketta Reef.
Page 57
EYRE REGION – SHERINGA AND FLINDERS BIOUNITS
terrestrial species. This is unusually high for
an island of this nature.
−
−
−
The islands of the Investigator Group contain
significant breeding colonies of Australian Sea
Lions (Neophoca cinerea) and New Zealand
Fur Seals (Arctocephalus forsteri). Breeding
colonies of sea lions have been recorded on
Ward Island (43 pups, estimated population
206), and Pearson island (35 pups, estimated
population 168). While possible breeding
occurs on Dorothee Island (Gales 1990). Haul
out sites occur on SE Ward, North Veteran
and Top Gallant (Gales et al. 1994). Breeding
colonies of fur seals have been recorded on
Pearson and Ward (64 pups, estimated
population 314), while haul outs occur on
Pearson, North Veteran and Dorothee Islands
(Shaughnessy et al. 1994).
The Investigator Group contains significant
colonies of protected seabird species, such as
the Little Penguin, Short-tailed Shearwater
and the White-faced Storm Petrel (Eckert
1970). Two colonies of the `vulnerable' Fairy
Tern occur on Pearson Island. Colonies of the
Little Penguin occur on Dorothee Island and
Pearson Island (Copley 1996). Colonies of the
Short-tailed Shearwater occur on Dorothee
Island (1,896 pairs), North Veteran (474
pairs), Topgallant Island (474 pairs), and
Ward Island (1,896 pairs) (Copley 1996).
Colonies of the White-faced Storm Petrel
occur on Dorothee Island (5,200 pairs),
Topgallant Island (3,900 pairs) and Ward
Island (326 pairs) (Copley 1996). Breeding
colonies of the Pacific Gull occur on Pearson
and Dorothee Island. Caspian Terns breed on
Pearson Island, while the Red-tailed
Tropicbird has been recorded on Pearson and
Flinders Island. The Investigator Group of
Islands is on the Register of the National
Estate.
An expedition to Pearson Island in 1969
showed the waters surrounding the island
contained highly diverse and abundant flora,
extending beyond 40 m deep (Shepherd &
Womersley 1971). This deep algal growth has
been attributed to the clear oceanic water
allowing high light penetration and adequate
water movement. There were differences
found in species assemblages between rough
and sheltered sites around the island. A richer
flora of Chlorophyta and Rhododphyta was
developed at the rougher sites whereas the
Phaeophyta were more abundant at the
sheltered sites (Shepherd & Womersley 1971).
Few subtidal grazing animals were observed,
although the giant Turban Dinassovica
jourdani was observed occasionally at depths
below about 20m in roughwater localities
where it browses on red algae.
−
A comparison between the Pearson Island and
West Island (off the Fleurieu Peninsula) flora
showed several important differences.
Pearson Island flora is richer in Chlorophyta
and Phaeophyta, although similar in the
number of Rhodophyta (however, further
collecting at Pearson Island is likely to
increase the total number of species,
particularly the Rhododphyta). There was
also greater species diversity at Pearson
Island, especially in the Rhodophyta
(Shepherd & Womersley 1971).
−
Topgallant Islands have high aesthetic marine
topographic
features.
The
benthic
communities have one of the highest levels of
biodiversity for ascidians, and marine algae in
the world (S.Shepherd, SARDI, pers.comm.).
−
Fish fauna of the Investigator Group of islands
is diverse (Kuiter 1983, Branden et al. 1986).
A total of 20 species was recorded at
Topgallant Island, 13 species at Hotspot, 15
species at Ward Island, and 16 species at
Pearson Island. Of particular significance is
the abundance of large fishes, such as the Blue
Groper (Achoerodus gouldii) that were
recorded in 15 out of 18 transects. These reefs
are rarely visited by spear-fishermen and
consequently, reveal fish abundances in
virtually unexploited conditions (Branden et
al. 1986).
Other Areas of Recognised Conservation
Significance
−
Waterloo Bay is a highly favourable habitat
for abalone production (S.Shepherd, SARDI,
pers.comm.).
−
Waterloo Bay has a very high level of habitat
diversity. Within Waterloo Bay, a total of 7
benthic macroalgal communities have been
identified on rocky substratum (Shepherd &
Womersley 1981). These included a roughwater algal turf community (comprising
predominantly stunted brown fucoid algae), a
red algal shade community, two Ecklonia
radiata communities (with Cystophora
platylobium and Acrocarpia paniculata as codominants),
a
Cystophora-complex
community (dominated by 9 species of
Cystophora),
a
Cystophora-SargassumOsmundaria community, and a community
dominated by Scaberia agardhii. On sandy
substratum, 5 seagrass communities have been
identified, dominated by Heterozostera
tasmanica, Amphibolus antarctica, Posidonia
australis, P.sinuosa with P.angustifolia, and
P.ostenfeldii (Shepherd & Womersley 1981).
Page 58
EYRE REGION – SHERINGA AND FLINDERS BIOUNITS
1.2 Physical
Geological Monuments
−
2
Drummond Point is "geological monument" of
State significance. Features of geological and
geomorphological interest include: welldeveloped shore platforms; Archaean Kiana
Granite (amongst the oldest rocks in South
Australia); and a major mylonite zone.
OTHER VALUES
2.1 Commercial Fisheries
Major single species fisheries in this region include
Greenlip and Blacklip Abalone and Southern Rock
Lobster. There is also a considerable marine
scalefish fishery targeting mainly King George
Whiting by hand line.
Although license holders are not restricted to fishing
in this biounit, the following licenses are registered in
this area:
−
Elliston: 1 northern zone Rock Lobster
license, 1 restricted marine scalefish license, 3
unrestricted marine scalefish licenses.
In 1994/95 and 1995/96 a total of 64263 and 49302
kg of Blacklip was harvested within this region,
and represented 20.7% and 17.7% of the total
Blacklip Western Zone catch (or 13.00% and
10.65% of the total catch for Blacklip in South
Australian waters).
In contrast, the offshore Flinders Biounit is one of
the major abalone fishing grounds in South
Australia. In 1994/95 and 1995/96 a total of 52236
and 62819 kg of Greenlip was harvested within the
Flinders Biounit (ie. MapCode 9A-H, 8P, 10C,
Flinders Island, The Hotspot, Ward Islands,
Pearson Islands), and represented 23.0% and 27.8%
of the total Greenlip Western Zone catch (or
13.87% and 16.78% of the total catch for Greenlip
in South Australian waters). In 1994/95 and
1995/96 a total of 30,681 and 40,947 kg of Blacklip
was harvested within this region, and represented
9.9% and 14.7% of the total Blacklip Western Zone
catch (or 6.21% and 8.84% of the total catch for
Blacklip in South Australian waters).
The `Hot Spot' near Ward Island and Waterloo Bay
are very productive sites for commercial abalone
harvesting. Elsewhere, abalone reefs are scattered
throughout Anxious Bay, the offshore islands, the
Elliston Cliffs (where abalone are found in the top 2
metres down to 20-25 metres, where it ends in sandy
bottom), and the mouth of Venus Bay (S.Shepherd,
SARDI, pers.comm.).
Abalone
The Western Zone for commercial abalone fishery is
all those waters west of the latitude 136o30' east and
includes all the waters of the management plan.
There are 23 license holders in this zone.
Within this region, most of the Greenlip Abalone is
presently harvested within the offshore Flinders
Biounit, while the Blacklip Abalone fishery is
significant in both the offshore and also, the
inshore waters of the Sheringa Biounit. In 1994/95
and 1995/96 a total of 3309 and 2589 kg of
Greenlip was harvested within the Sheringa Biounit
(ie. MapCode 8F-H, 8J-N, 10A-B, 11A-C,
Waterloo Bay, Elliston Cliffs to Kiana Cliffs
region), and represented 1.5% and 1.1% of the total
Greenlip Western Zone catch (or 0.88% and 0.69%
of the total catch for Greenlip in South Australian
waters).
There are 4 abalone divers for 4 licenses in the
Elliston region. In addition, a further 19 divers work
the waters off Elliston, occasionally diving in
Waterloo Bay, but most commonly working off
Anxious Bay and out to the offshore islands
(T.Whibey, pers.comm). Blacklip Abalone are taken
on calm seas from the shallower waters, while
Greenlip Abalone are taken from the deeper water
when there is a swell.
Marine Scalefish
During 1995/96 and 1996/97, 21 and 34
commercial licence holders (made up of Marine
Scalefish, Restricted Marine Scalefish and
Northern Zone Rock Lobster licence categories)
caught commercial marine scalefish species from
the Anxious Bay and inshore Investigator Group
region (ie. Fishing Zone 15), respectively. License
holders expended approximately 570 and 899 boat
days effort fishing these waters during 1995/96 and
1996/97, respectively. The marine scalefish catch
for this region (ie. Fishing Zone 15) represented
133,221 kg in 1995/96 and 283,665 kg in
1996/97(or 1.28% and 2.79% of the total catch for
the marine scalefish fishery in South Australian
waters).
Page 59
EYRE REGION – SHERINGA AND FLINDERS BIOUNITS
Licenses will be considered for a maximum of
60ha of aquaculture development within this
zone, but not within Waterloo Bay and 1km of
Waldegrave Islands, Cap Island, Lake
Newland, Talia Caves and Venus Bay
Conservation Parks.
There are 5 marine scalefish licenses in Elliston,
comprising 3 A class and 2 B class fishing licenses.
Operators fish mainly in the vicinity of Anixous Bay,
Waldegrave Island and Flinders Island (T.Whibley,
pers.comm.).
Southern Rock Lobster
Drummond Point Policy Area
This biounit represents a significant region for
lobster fishing in South Australia. In 1995/96 and
1996/97 a total of 41 and 34 licensed operators
fished in the Anxious Bay and inshore Investigator
Group region (ie. Fishing Zone 15), catching
approximately 168,235 and 161,534 kg of lobsters,
respectively (or 3.23% and 3.16% of the total catch
for Southern Rock Lobster in South Australian
waters). During this same period, a total of 11 and
5 licensed operators fished in the offshore
Investigator Group region (ie. Fishing Zone 14),
catching approximately 6, 152 and 4,557 kg of
lobsters, respectively (or 0.12% and 0.09% of the
total catch for Southern Rock Lobster in South
Australian waters). In the inshore region, south of
Elliston, a total of 15 and 15 licensed operators
fished in the Sheringa Biounit region (ie. Fishing
Zone 18), catching approximately 15,342 and 10
878 kg of lobsters, respectively (or 0.30% and
0.21% of the total catch for Southern Rock Lobster
in South Australian waters).
One lobster boat works from Elliston as far north as
Talia Caves, south to Tungketta Reef and out to
Flinders Island. In addition, another two or so boats
come from Port Lincoln to work the grounds
(T.Whibley, pers.comm.).
2.2 Aquaculture
−
Flinders
No marine-based aquaculture current exists in this
region. The Elliston Aquaculture Management Plan
(Ashman 1996) recommends limited aquaculture
development in the region:
Investigator Group Policy Area
−
Investigator Group Zone (coastal waters,
within 3nm of the coast, surrounding Ward
Islands, Pearson Isles, Veteran Isles, Dorothee
Island, and Topgallant Island) – zoned to
maintain and protect current uses and values.
Licenses will not be considered for
aquaculture development within this zone.
−
Flinders Island Zone – zoned to provide for
aquaculture development. Licenses will be
considered for a maximum of 40ha of
aquaculture development within this zone.
Sheringa
Current aquaculture in this region is centred on
Waterloo Bay (Elliston) and the southern end of
Anxious Bay (Ashman 1996). No marine-based
aquaculture current exists in this region. The Lower
Eyre Peninsula Aquaculture Management Plan
(Aquaculture Group, PIRSA 1997) and the Elliston
Aquaculture Management Plan (Ashman 1996)
recommends aquaculture development in the
following areas:
2.3 Recreation and Tourism
Fishing
−
Anxious Bay: boat, beach, and rock fishing.
Major species: King George Whiting, Sand
Flathead, Yelloweye Mullet, Australian
Salmon, Snapper, Snook, Sweep, Garfish,
Tommy Rough, Trevally, Toothbrush
Leatherjacket, Silver Drummer and Southern
Calamari.
−
Flinders Island: boat, beach, and rock fishing.
Major species: King George Whiting, Sand
Flathead, Yelloweye Mullet, Australian
Salmon, Snapper, Snook, Sweep, Garfish,
Tommy Rough, Trevally, Toothbrush
Leatherjacket, Silver Drummer and Southern
Calamari.
Elliston Policy Area
−
Elliston Zone (all iwaters of the Elliston
Policy Area, within 3nm of coast, from mouth
of Venus to south of Sheringa Beach,
excluding Venus Bay, but including Cap
Island, Waldegrave Islands and The Watchers)
– zoned to provide for aquaculture
development.
Drummond Point Zone (ie. inshore waters
from Sheringa Beach south to Point Sir Isaac,
east to Frenchman Bluff) – zoned to protect
conservation values and existing fishing,
recreational and tourist use. Licenses will not
be considered for aquaculture development in
this zone.
Page 60
EYRE REGION – SHERINGA AND FLINDERS BIOUNITS
−
Elliston Waterloo Bay: boat, jetty, beach, and
rock fishing. Major species: King George
Whiting, Sand Flathead, Yelloweye Mullet,
Australian Salmon, Snook, Sweep, Garfish,
Tommy Rough, Trevally, Silver Drummer and
Southern Calamari.
−
Locks Well: beach fishing. Major species:
Sand Flathead, Yelloweye Mullet, Australian
Salmon and Tommy Rough.
−
Sheringa: beach and rock fishing. Major
species: King George Whiting, Sand Flathead,
Yelloweye Mullet, Australian Salmon and
Tommy Rough.
2.4 Scientific Research and Education
−
Islands in the Investigator Group have long
been the site of a number of marine and
terrestrial biological studies by both, fisheries
scientists and researchers from the SA
Museum and various research institutions
(Shepherd 1969, Specht 1969, Shepherd &
Womersley 1970, Twidale 1971, Branden et
al. 1986). The most well studied of these
islands is Pearson Island, where research dates
back to a scientific expedition to the island in
1923. In 1969, a comprehensive marine
biological survey of Pearson Island was
conducted jointly by the Department of
Fisheries and Fauna Consevation of South
Australia and the Royal Society of South
Australia (see Shepherd & Womersley 1970,
Burn 1973, Seed 1973, Watson 1973).
Because of its relatively undisturbed state, it is
probably the most scientifically important of
the State's offshore islands.
−
Researchers from the NPWS regularly
conduct surveys of Australian Sea Lion and
New Zealand Fur Seal colonies in this region.
−
Fisheries research in this area includes, regular
catch and effort monitoring of the major
commercial fisheries in the region (Abalone,
Southern Rock Lobster, Western King Prawn,
and marine scalefish); regular research and
monitoring of larval fish stocks; regular
research and monitoring of Blacklip and
Greenlip Abalone field stocks; and regular
research and monitoring of South Rock
Lobster field stocks.
Tourism
−
Elliston is a popular site on the shores of
Waterloo Bay.
Its rugged cliffs and
spectacular coastline have great aesthetic
appeal. The town itself is popular for its clear
and unspoilt beaches and fishing.
The
sheltered bays offer swimming, sailing, diving
or watersports. Elliston is a popular campsite
for recreational diving clubs.
−
`Blackfellows' at Anxious Bay is a popular
surfing spot and Sheringa Lagoon is a popular
camping spot.
−
The Investigator Group of Islands are popular
for charter boats (eg. Failie Charters) for
fishing, SCUBA diving, Southern Rock
Lobster, and shark spotting (especially at
Pearson Island).
−
Recreational divers target Waterloo Bay, Talia
Caves and Anxious Bay for Southern Rock
Lobster, Abalone and occasionally, Scallops.
−
SCUBA diving: Pearson Island is a recognised
dive spot and listed in `Dive South Australia:
The Best Dive Sites in South Australia’
(Diving Industry Association of South
Australia). The island is recognised for its
populations of seals and dolphins, fish
(particularly Blue Devils, Leafy Seadragons,
and giant Blue Groper) and also, giant
sponges, gorgonians and soft corals.
2.5 Adjacent Land Use
National and Conservation Parks
−
Investigator Group Conservation Park (117
ha). This park excludes the two largest islands
in the Investigator Group, Flinders and
Pearson Islands. Flinders Island is held as a
pastoral lease while Pearson Island is a
Lighthouse Reserve managed by the
Commonwealth Government.
−
Cap Island Conservation Park (8 ha).
Page 61
EYRE REGION – SHERINGA AND FLINDERS BIOUNITS
Agriculture/Industry
−
The remains of 3 shipwrecks are known to
occur in the region and are protected under
Commonwealth legislation: the schooner
`Vulcan’ which was wrecked at Flinders
Island in 1845, and the schooners
`Freebridge’ and `Fanny Wright’, which were
wrecked in Waterloo Bay in separate incidents
in 1877.
−
The cutter `Fire Fly’ was wrecked in 1866,
somewhere in Anxious Bay, near Elliston, but
has not been located. In addition 2 other
wrecks are of historical interest, but have not
been declared at this stage (Ashman 1996): the
ketch `Lady Flinders’ which was wrecked at
Flinders Island in 1937 and the screw steamer
`Kapara’ which was also wrecked at Flinders
Island in 1942.
3
CURRENT CONSERVATION STATUS
OF THE SHERINGA AND FLINDERS
BIOUNITS
Apart from the township of Elliston, there is little
urban development along this biounit. Most
adjacent coastal land in this biounit is used for
agriculture. There is a pastoral lease on Flinders
Island.
−
Urban Centres
Elliston (population 209).
2.6 Significant Cultural and Historical Features
Aboriginal
−
Blackfellows, near Cape Finniss: possible site
of a major massacre of indigenous inhabitants
(A. Nicholson, pers.comm.).
−
Hill Bay, Drummond Point (not dated): an
occupation complex consisting of middens
and artefact scatters.
Has potential for
National Estate listing (A. Nicholson,
pers.comm.).
3.1 Sheringa Biounit
European
A number of coastal structures and sites in
this region have recognised heritage value:
−
Marine Reserves
None
Sealing site at Flinders Island (registered on
the State Heritage Register).
−
Marine Parks
None
−
Elliston jetty and a cast iron navigation light
(both on the State Heritage Register).
−
−
Venus Bay and Port Kenny jetties (considered
to have local heritage value).
•
−
3.2 Flinders Biounit
Shipwrecks
−
A number of shipwrecks are located in this
region. The waters of Venus Bay and up to
the Anxious Bay closing line, are covered by
the (South Australian) Historic Shipwrecks
Act 1976. This allows for the protection of
shipwrecks through the declaration of
individual wrecks as historic. Waters outside
the Anxious Bay closing line fall under the
jurisdiction of the (Commonwealth) Historic
Shipwrecks Act 1976. Wrecks within these
waters that are in excess of 75 years old are
automatically protected under this act. Other
wrecks may be protected under this Act if of
significant value.
Netting Closure
Waterloo Bay (all of the waters inside of
Waterloo Bay, Elliston, situated north east of a
line from Wellington Point to Salmon Point).
−
Marine Reserves
None
−
Marine Parks
None
−
Netting Closure
None.
Page 62
EYRE REGION – SHERINGA AND FLINDERS BIOUNITS
4
AREAS OF HIGH CONSERVATION
VALUE IN THE SHERINGA AND
FLINDERS BIOUNITS
Cap Island Conservation Park
−
4.1 Sheringa Biounit
Waterloo Bay
−
Prime
IUCN
Conservation
Values:
biodiversity, research, cultural, social values
(IUCN Category II). IUCN Identification
Criteria: naturalness (not subject to humaninduced change), biogeographic (representative
marine habitats), ecological (ecological
integrity, diversity of marine habitat types, reefs,
seagrass meadows), economic (fisheries,
tourism),
social
(historic
shipwrecks`Freebridge’,
`Fanny
Wright’,
scenic
amenities), scientific (scientific research and
monitoring-abalone), practicality (accessibility).
Drummond Point
Prime IUCN Conservation Values: cultural
values, biodiversity (IUCN Category III).
IUCN Identification Criteria: naturalness (not
subject
to
human-induced
change),
biogeographic
(geological
monumentDrummond Point), ecological (White-faced
Storm Petrel, White-fronted Tern), economic
(Southern Rock Lobster, significant area for
Blacklip Abalone, tourism), social (aboriginal
occupation complex at Hill Bay, recreation,
scenic
amenities),
scientific
(scientific
monitoring), national (potential for listing on
the Register of the National Estate), practicality
(insulation).
Lake Hamilton
−
Prime IUCN Conservation Values: rare and
endangered species/habitats, biodiversity,
aesthetics, research (IUCN Category II).
IUCN Identification Criteria: naturalness (not
subject
to
human-induced
change),
biogeographic (representative marine habitats),
ecological (wetland habitats, threatened
waterbirds - Hooded Plover, Osprey, Cape
Barren Goose, ecological integrity), economic
(Southern Rock Lobster, fisheries, tourism),
social (scenic amenities), scientific (scientific
monitoring), national (Wetland of National
Importance-Lake
Newland),
practicality
(insulation, accessibility, compatibility-adjacent
to Lake Hamilton wetland,).
Sheringa Beach and Lagoon
−
Prime
IUCN
Conservation
Values:
biodiversity,
rare
and
endangered
species/habitats, research (IUCN Category
IA).
IUCN Identification Criteria:
naturalness (not subject to human-induced
change), biogeographic (representative marine
habitats), ecological (wetland habitats,
threatened birds particularly Hooded Plover,
Cape Barren Goose, ecological integrity),
economic (Southern Rock Lobster, significant
area for Blacklip Abalone, tourism), social
(recreation, scenic amenities), scientific
(scientific
monitoring-abalone),
national
(recognised wetland of importance), practicality
(insulation, accessibility, compatibility-adjacent
to Sheringa Lagoon wetland).
Prime
IUCN
Conservation
Values:
biodiversity, research (IUCN Category IA).
IUCN Identification Criteria: naturalness (not
subject
to
human-induced
change),
biogeographic (representative marine habitats),
ecological (breeding colonies of White-faced
Storm Petrel, White-fronted Tern), economic
(Southern Rock Lobster, Blacklip Abalone,
fisheries, tourism), social (scenic amenities,
recreation), scientific (scientific monitoring),
national (Register of the National Estate),
practicality (insulation, compatibility-adjacent
to Cap Island Conservation Park).
4.2 Flinders Biounit
Investigator Group
−
Prime
IUCN
Conservation
Values:
biodiversity, aesthetic values, rare and
endangered species/habitats, research (IUCN
Category IB). IUCN Identification Criteria:
naturalness (not subject to human-induced
change), biogeographic (representative marine
habitats, unique geology), ecological (benthic
biodiversity, Pearson Island Rock Wallabies,
Australian Sea Lions, breeding colonies and
haul out sites for New Zealand Fur Seals-Ward,
Veteran, Pearson, Dorothee Islands, breeding
colonies and haul out sites for Australian Sea
Lions-Ward, Pearson, Dorothee, Veteran,
Topgallant, breeding/nesting colonies of
seabirds - Little Penguin, Short-tailed
Shearwater, White-faced Storm Petrel, Fairy
Tern, Sooty Oystercatcher, Pacific Gull),
economic (significant area for Greenlip
Abalone, Blacklip Abalone, fisheries, tourism),
social (wilderness values, scenic amenities, past
historical studies, recreational use), scientific
(past and present scientific research – Pearson
Isles, Topgallant Islands), national (Register of
Page 63
EYRE REGION – SHERINGA AND FLINDERS BIOUNITS
the National Estate-Investigator Group
Conservation Park), practicality (extension of
Investigator Group Conservation Park,
compatibility).
Flinders Island
−
Prime
IUCN
Conservation
Values:
biodiversity, cultural values, rare and
endangered species/habitats, research (IUCN
Category II). IUCN Identification Criteria:
naturalness (scenic amenities), biogeographic
(representative marine habitats), ecological
(nesting sites for Ospreys, White-bellied Sea
Eagle, breeding sites for Little Penguins),
economic (significant area for Blacklip
Abalone, Greenlip Abalone, fisheries, tourism),
social (historic shipwrecks - `Vulcan’, `Lady
Flinders’, `Kapara’, recreation), scientific
(scientific monitoring), national (Register of the
National Estate), practicality (extension of
Investigator Group Conservation Park,
compatibility).
Page 64
EYRE REGION – DOUGLAS BIOUNIT
VIII MARINE BIOGEOGRAPHY AND CONSERVATION VALUES OF THE
DOUGLAS BIOUNIT
This biounit extends from Drummond Point to Point Sir Isaacs on the south-eastern tip of Eyre Peninsula, and
covers an area of 67,645 ha and a coastal distance of approximately 73 km. It is oriented in a generally southerly
direction into the Southern Ocean.
MARINE BIOGEOGRAPHY
1
OCEANOGRAPHY
This biounit has high energy coastline with low
energy bays. From Cape Catastrophe to Point Sir
Isaac (167 km) the south-west facing coast is exposed
to high energy and is one of the highest wave energy
shorelines in Australia, rivalling Canunda in the
South-East (Short & Hesp 1984).
Open coast sea temperatures vary from a mean
summer sea surface temperature of 18oC to a mean
winter sea surface temperture of 14oC. The inshore
coastal regions are under the influence of seasonal
coldwater, nutrient-rich coastal upwellings which
occur close to the coast, which can result in an
offshore sea surface temperature gradient of 18oC to
inshore temperatures of 11oC in inshore areas during
the summer months (Wenju et al. 1990). There
appears to be a relationship between the upwellings
and the pilchard numbers in these areas (Ward &
McLeay 1998).
2
GEOLOGY
AND
GEOMORPHOLOGY12
COASTAL
From Point Sir Isaac to Point Drummond (133 km,
including Port Douglas) there is 73 km of open coast
shoreline with highly variable orientation and
exposure, coupled with more than 60 km of highly
crenulate bay shoreline in Port Douglas (Coffin Bay).
The protection from the Southern Ocean swell
afforded by the Coffin Bay Peninsula has produced a
far lower energy coastline that the southern coast.
Consequently, while Holocene sedimentation has
been extensive, most is confined to intertidal and
subtidal sandflats and bay floor deposits, with beachbarrier-dune deposits only beginning to appear along
the northern section of coast, which is increasingly
exposed to the ocean wave conditions.
12
Port Douglas (including Kellidie and Mount Dutton
Bays) is the largest bay on the Eyre Peninsula, with
an overall area of 120 km2 and 60 km of shoreline.
Coffin Bay is a more protected bay with a low energy
open coast. The present shoreline of Port Douglas,
Mount Dutton and Kellidie Bays consists of three
types: (i) stable dune calcarenite cliffs, usually only a
few metres high and notched in the intertidal zone
dominate the northern shoreline, and are common on
southern promontories; (ii) low energy intertidal
deposits consisting of shelly sandflats backed by
supratidal samphire flats in very protected
environments, such as upper Mount Dutton Bay,
Kellidie Bay and Yangie Bay; (iii) low energy
reflective beaches, usually backed by small foredunes
and fronted by low gradient sandflats in the more
exposed locations, particularly along the southern
and western shores of Port Douglas and Point
Longnose.
A number of offshore islands occur in this biounit:
−
Rocky Island (North): entirely basement rock.
−
Mt Dutton Bay Islands (7 islands).
3
BIOLOGY
Major Inshore Habitats
−
Major intertidal habitats in the region include
bays, sandy beaches and some rocky shores
and islands.
−
Of the total inshore subtidal habitats mapped
in the biounit (37 151ha), sandy bottoms
comprise 18,619ha (50.1%), limestone reefs
comprise 9,965ha (26.8%), and seagrass
meadows comprise 8,567ha (23.1%).
From Eyre Coast Protection District Study Report.
Page 65
EYRE REGION – DOUGLAS BIOUNIT
Major Benthic Communities
•
Macroalgal
−
Along the exposed rocky granite shores and
reefs in this region (eg. Greenly Beach, Point
Drummond,
Rocky
Island),
subtidal
macroalgal communities are dominated by the
fucoids, Cystophora monoliformis, C.siliquosa,
and C.monolifera and Acrocarpia paniculata
and the red algae, Osmundaria prolifera and
Haliptilon, in shallow waters (ie. 5m). In deeper
waters, rocky reef communities are dominated
by Ecklonia radiata and Scytothalia dorycarpa,
with species of Cystophora (C.platylobium,
C.racemosa, C.moniliformis) as sub-dominants,
and also a range of large understorey red algae
(eg. Plocamium, Osmundaria, Phacelocarpus,
Carpophyllis), encrusting corallines, and green
algae (Caulerpa flexilis, C.obscura).
•
Seagrasses
−
There are extensive seagrass meadows in this
region, due to the dominance of sheltered
embayments.
Seagrass meadows are
dominated by Posidonia angustifolia,
Heterozostera tasmanica and Halophila
australis and the green alga, Caulerpa
cactoides (eg. Port Douglas, Dutton Bay).
Coastal and Offshore Islands (or Reefs)
−
Rocky Islands (North).
−
Mt Dutton Bay Islands (7 islands).
Rivers and Estuaries
−
Port Douglas (including Kellidie and Mount
Dutton Bays): 25-50% of the catchment has
been cleared of natural vegetation. This low
energy bay consists of intertidal sand/mudflats
(0.86 km2), patchy mangroves (3.10 km2) and
samphires.
MARINE CONSERVATION VALUES
1
SIGNIFICANT
BIOLOGICAL
PHYSICAL FEATURES
AND
1.1 Biological
Coastal and Marine Wetlands of National
Importance
−
The Coffin Bay coastal wetland system has
been identified as a wetland of national
importance (see ANCA 1996). The Coffin
Bay coastal system encompasses the coastline
of the Coffin Bay Peninsula, including Avoid
Bay and offshore islands, Gunyah Beach,
Seven Mile Beach and the waters of Port
Douglas (including Yangie, Kellidie and
Mount Dutton Bays). Coffin Bay is the
largest bay on the Eyre Peninsula, and the
second largest estuary in South Australia (after
the Coorong), with an overall area of 120 km2
and approximately 60 km of shoreline. The
estuary itself is highly significant at a State
level in that only 25-50% of its catchment area
has been cleared of native vegetation (Bucher
& Saenger 1989). All other estuaries in South
Australia (except Franklin Harbour) are
considerable `developed' with more than 75%
of their catchment areas modified.
The
Coffin Bay wetlands have been identified as
areas of international importance for
shorebirds by Watkins (1993).
The
availability of undisturbed coastal cliff habitat
and rocky offshore islands makes the area a
significant breeding refuge for the Osprey,
Pandion haliaetus and White-bellied SeaEagle, Haliaeetus leucogaster (ANCA 1996).
The islands support a diversity of wader
species and are major breeding sites for terns,
gulls and oyster catchers. The area is noted
for its breeding population of the Eastern Reef
Egret, Egretta sacra, while the beaches are
important summering sites for Sanderlings,
Calidris alba. Threatened waterbirds in the
area include the Hooded Plover, Thinornis
rubricollis (Nv, Sv), White-bellied Sea-Eagle
(Sv), Osprey (Sv), Cape Barren Goose,
Cereopsis novaehollandiae (Sv), Musk Duck,
Biziura lobata (Sv), Eastern Curlew,
Numenius madagascariensis (Sv), Fairy Tern,
Sterna nereis (Sv), and Eastern Reef Egret
(Sr). A total of 63 waterbird and seabirds
have been recorded in the region; 22 are listed
under international treaties. A total of 18
species breed in the region (see ANCA 1996).
Page 66
EYRE REGION – DOUGLAS BIOUNIT
−
−
The substantial areas of marine wetlands in
this estuary provide habitats and nursery areas
for both estuarine and offshore fish stocks,
particularly
King
George
Whiting,
Sillaginodes punctata. The size of the estuary
and the extent and diversity of its associated
wetlands suggest that its contribution to the
ecology of the local area would be significant
(Bucher & Saenger 1989). Leathery turtles
Dermochelys coriacea (Nv, Se) are seen
regularly in Port Douglas and Mt Dutton Bay
in late summer. A wide range of marine
mammals (seals, dolphins and 6 species of
whales) are regularly recorded along the
Coffin Bay Peninsula and offshore islands
between August and December (ANCA 1996).
Coffin Bay National Park (Port Douglas) is
regarded as one of the few areas of substantial
wilderness quality remaining in the settled,
more temperate areas of South Australia
(Lesslie & Taylor 1983).
The southern
coastline has striking sandstone cliffs, sandy
beaches and excellent views of the offshore
islands, while the northern coastline has
tranquil bays and the samphire (Sarcocornia
blackiana) swamps in Port Douglas. This
range of environments supports 148 species of
birds, 26 species of reptiles and two or three
species of terrestrial mammals although at
least eight more species are known to have
inhabited the area at the time of European
settlement (Preece 1985, Martin 1994). Birds
recorded on the cliffs include Rock Parrots,
White-bellied Sea Eagles and Ospreys. The
sandy beaches are breeding sites for Redcapped Plover (Charadrius ruficapillus), the
Pied
Oyster-catcher
(Haematopus
longirostris) and the Hooded Plover
(Thinornis rubricollis). The swamps attract
large numbers of migratory waders in spring
and summer from the Northern Hemisphere.
Mt Dutton Bay Islands Conservation Park
(Port Douglas) consists of seven small islands
in the bay. Although disturbed, they are still
areas of biological significance, especially as
breeding sites for birds. For instance, a total
of nine species of seabirds breed on Rabbit
Island, including Little Penguins (Eudyptula
minor), Eastern Reef Egrets (Ardea sacra),
Pied
Oystercatchers
(Haematopus
longirostris),
Sooty
Oystercatchers
(Haematopus fuliginosus), Silver Gulls (Larus
novaehollandiae), Pacific Gulls (Larus
pacificus), Caspian Terns (Hydroprogne
caspia), Fairy Terns (Sterna nereis) and
Crested Terns (Sterna bergii) (Gill 1985a).
Eastern Reef Egrets also breed on Goat Island
(Gill 1980) while Buff-banded Rails
(Rallus philippensis) breed on Rabbit Island.
The largest of the Brothers is a major breeding
site for Crested Terns, Caspian Terns and Rock
Parrots (Neophema petrophila) (Gill 1985b).
Single Sooty Terns (Sterna fuscata), which
normally breeds only on islands off the
Western Australian, Northern Territory and
Queensland coasts, have been recorded. The
islands are on the Register of the National
Estate.
−
Kellidie Bay Conservation Park has dense
thickets of Melaleuca neglecta which line the
swamps margin which is an increasingly rare
vegetation type on Eyre Peninsula (Preece
1985). The swamps attract several uncommon
birds such as the Wood Sandpiper (Tringa
glareola),
Latham's
Snipe
(Galinago
hardwickii), and the Buff-banded Rail (Rallus
phipippensis). The Marsh Harrier (Circus
aeruginosus) is also found in swampy areas.
−
Extensive seagrass meadows. The seagrasses
in the Port Douglast represent the second
largest areas of seagrass on the Eyre Coast.
The sheltered embayments of the Eyre Coast,
particularly Streaky and Smoky Bay (ie.
Streaky Biounit), and Port Douglas (ie.
Douglas Biounit), support extensive seagrass
meadows. These extensive seagrass meadows
flourish in shallow clear waters, generally in
waters less than 15m, and provide the basis for
the significant productivity of the coastal
regions in terms of fisheries and prawn
production. Seagrasses cover a total area of
approximately 86,163 ha in Streaky and Smoky
Bay, and 8 567 ha in Port Douglas. Together,
the seagrasses of the Eyre Coast represent
approximately 15% (ie. 1,407 km2) of the total
area of seagrasses recorded in South Australia
(ie. 9,612 km2).
Other Areas of Recognised Conservation
Significance
−
Rocky Island (North) Conservation Park: haul
out and basking sites of the New Zealand Fur
Seal (Arctocephalus forsteri) has been
recorded on Rocky (North) (Shaughnessy et
al. 1994). Haul out and possibly breeding
colonies of the rare Australian Sea Lions
(Neophoca cinerea) occur on the Rocky Island
(North) (Watts & Ling 1985, Gales 1990).
The park is on the Register of the National
Estate.
Page 67
EYRE REGION – DOUGLAS BIOUNIT
1.2 Physical
Geological Monuments
−
2
Drummond Point is a "geological monument"
of State significance. Features of geological
and geomorphological interest include: welldeveloped shore platforms; Archaean Kiana
Granite (amongst the oldest rocks in South
Australia); and a major mylonite zone.
OTHER VALUES
2.1 Commercial Fisheries
Major single species fisheries include Southern Rock
Lobster, Abalone and Western King Prawn. Marine
scalefish fisheries in this region primarily target King
George Whiting and is of major State importance.
Western King Prawn
This biounit is located within the waters of the West
Coast prawn fishery, which comprises 3 license
holders (ie. Boats). All vessels fish within the waters
of this biounit (ie. Fishing Zones 27), the Newland
Biounit (ie. Fishing Zone 15), and the Nuyts Biounit
(ie. Fishing Zone 8). In 1995/96 and 1996/97 a total
of 200,764 and 166,414 kg was caught for this
fishery, with a total effort of 3,144 and 2,778 hours,
respectively (or 8.84% and 8.22% of the total catch
for Western King Prawn in South Australian
waters).
Southern Rock Lobster
In 1995/96 and 1996/97 a total of 23 and 27
licensed operators fished in the Douglas Biounit
(ie. Fishing Zone 27), catching approximately
42,151 and 49,754 kg of lobsters, respectively (or
0.82% and 0.97% of the total catch for Southern
Rock Lobster in South Australian waters).
Abalone
Blacklip Abalone and some Greenlip Abalone is
presently commercially harvested within the
Douglas Biounit, (ie. MapCode 12A-C, 13A-C,
Drummond Point – Frenchman Bluff region), but
due to confidentiality constraints these figures are
not available.
In 1994/95 and 1995/96 a total of 28,620 and
20,285 kg of Blacklip was harvested within this
region, and represented 9.2% and 7.3% of the total
Blacklip Western Zone catch (or 5.79% and 4.38%
of the total catch for Blacklip in South Australian
waters).
Marine Scalefish Fisheries
This biounit represents one of the most significant
regions for the marine scalefish fishery in South
Australia. During 1995/96 and 1996/97, 63 and 59
commercial licence holders (made up of Marine
Scalefish, Restricted Marine Scalefish and
Northern Zone Rock Lobster licence categories)
caught commercial marine scalefish species from
the Douglas Biounit (ie. Fishing Zone 27),
respectively.
License holders expended
approximately 2028 and 1815 boat days effort
fishing these waters during 1995/96 and 1996/97,
respectively. The marine scalefish catch for this
region (ie. Fishing Zone 27) represented 2,438 618
kg in 1995/96 and 923,539 kg in 1996/97(or
23.45% and 9.11% of the total catch for the marine
scalefish fishery in South Australian waters).
Although license holders are not restricted to fishing
in this biounit, the following licenses are registered in
this area:
−
Coffin Bay: 7 unrestricted marine scalefish
licenses, 4 Southern Rock Lobster.
2.2 Aquaculture
Pacific Oyster farming is the only mariculture
industry in this coastal biounit. At present all activity
is concentrated in the Port Douglas region, which
represents one of the major regions for oyster
growing in South Australia. As such, significant
activity is present in western Mount Dutton Bay (11
approved leases) and Kellidie Bay (8 approved
leases). In addition to the approved leases, another 5
oyster lease applications are pending in this region,
all are located at the southern end of Horse Peninsula.
Yangie Bay, and sections of Mount Dutton Bay and
Port Douglas are presently not considered suitable for
aquaculture.
The
Lower
Eyre
Peninsula
Aquaculture
Management Plan (Aquaculture Group, PIRSA
1997) proposes the following level of aquaculture
development in this region:
Page 68
EYRE REGION – DOUGLAS BIOUNIT
Farm Beach Policy Area
−
Frenchman Management Zone (eastern waters
of Coffin Bay) – no existing aquaculture.
Licenses will considered for 50 ha of shellfish
aquaculture (5 R&D permits, 10 ha each). No
finfish aquaculture will be
considered in this area.
−
Coffin Bay Peninsula Management Zone
(western waters of Coffin Bay) – no existing
aquaculture. Licenses will not be considered
for aquaculture development within this zone.
−
−
−
−
−
Kellidie Bay Aquaculture Zone (central waters
of Kellidie Bay) – 40 ha of oyster culture
currently operating and is the maximum area
proposed for this zone. Lease areas must not
exceed 8 ha and a maximum of 2 ha from
existing leases can be relocated within this
zone.
−
Kellidie Bay Zone (remaining waters of
Kellidie Bay) - Licenses will not be
considered for aquaculture development
within this zone.
Farm Beach Zone (remaining waters of Coffin
Bay, not covered by above) – no existing
aquaculture. Licenses will not be considered
for aquaculture development within this zone.
Port Douglas Policy Area
−
Kellidie Bay Policy Area
Horse Peninsula Management Zone (waters of
Port Douglas, adjacent the Horse Peninsula) –
existing R&D shellfish aquaculture leases.
Licenses will be considered for a maximum of
15ha of oyster culture in this zone (and a
maximum of 5 leases will be considered).
Point Longnose Management Zone (waters of
Port Douglas, south of Point Longnose) – no
existing aquaculture.
Licenses will be
considered for a maximum of 20ha of oyster
culture within the zone, but no more than a
total area of 110ha of aquaculture
development will be considered in the Port
Douglas-Coffin Bay-Kellidie Bay-Dutton Bay
region.
Little Douglas Management Zone (central
waters of Port Douglas) – no existing
aquaculture. Licenses will be considered for a
maximum of 10 ha of oyster culture, but no
more than a total area of 110 ha of aquaculture
development will be considered in the Port
Douglas-Coffin Bay-Kellidie Bay-Dutton Bay
region.
Port Douglas Zone (remaining waters of Port
Douglas, not covered by above) – no existing
aquaculture. Licenses will not be considered
for aquaculture development within this zone.
Dutton Bay Policy Area
−
Dutton Bay Aquaculture Zone – 40 ha of
oyster culture currently operating and is the
maximum area proposed for this zone. One
lease may be considered for a nursery lease to
a maximum of 2 ha.
−
Lavender Bay Aquaculture Zone – no existing
aquaculture. Licenses will be considered for a
maximum of 8 ha of oyster culture within this
zone.
−
Bulldog Point Aquaculture Zone – no existing
aquaculture. Licenses will be considered for a
maximum of 8 ha of oyster culture within this
zone.
−
Dutton Bay North Aquaculture Zone – 4 ha of
oyster culture currently operating and is the
maximum are proposed for this zone. One
lease may be considered for a nursery lease to
a maximum of 2 ha.
−
Salt Creek Aquaculture Zone - 4 ha of oyster
culture currently operating and is the
maximum are proposed for this zone.
−
Mount Dutton Zone - Licenses will not be
considered for aquaculture development
within this zone.
Page 69
EYRE REGION – DOUGLAS BIOUNIT
Coffin Bay Policy Area
−
Coffin Bay Zone (waters of Yangie Bay,
Coffin Bay, south of Horse Peninsula) – 1
oyster lease currently operating. Licenses will
not
be
considered
for
aquaculture
development within this zone.
−
No marine-based aquaculture current exists in
the Point Sir Isaac to Frenchman Bluff to
Drummond Point to Point Sir Isaac region.
The Lower Eyre Peninsula Aquaculture
Management Plan (Aquaculture Group,
PIRSA 1997) proposes no aquaculture
development in this region:
−
2.4 Scientific Research and Education
−
Drummond Point Policy Area
−
Drummond Point Zone (ie. inshore waters
from Sheringa Beach south to Point Sir Isaac,
east to Frenchman Bluff) – licenses will not be
considered for aquaculture development in
this zone.
National and Conservation Parks
Fishing
−
−
Convention Beach: beach fishing. Major
species: Sand Flathead, Yelloweye Mullet,
Australian Salmon and Tommy Rough.
−
Farm Beach: boat fishing. Major species:
King George Whiting, Sand Flathead, Tommy
Rough and Garfish.
−
−
−
−
Coffin Bay, Kellidie Bay, Almonta: boat,
beach, jetty and rock fishing. Major species:
King George Whiting, Sand Flathead,
Yelloweye Mullet, Australian Salmon,
Garfish, Tommy Rough, Snapper and
Trevally.
Tourism
−
Coffin Bay: considered an unspoilt area for
fishing, watersports and family holidays. It is
considered an important wilderness area
(Lesslie & Taylor 1983). The `Oyster Walk'
at Coffin Bay is a 2.5 km guided tour through
native bushland.
Fisheries research in this area includes, regular
catch and effort monitoring of the major
commercial fisheries in the region (Abalone,
Southern Rock Lobster, Western King Prawn,
and marine scalefish); regular research and
monitoring of larval fish stocks; regular
research and monitoring of Blacklip and
Greenlip Abalone field stocks; and regular
research and monitoring of South Rock
Lobster field stocks.
2.5 Adjacent Land Use
2.3 Recreation and Tourism
−
SCUBA diving: Frenchman Bluff and Coles
Point are recognised reefs dives and listed in
`Dive South Australia: The Best Dive Sites in
South Australia’ (Diving Industry Association
of South Australia). The former is a shallow
shore dive (down to 12m) suitable for novices,
the latter dive (12-20m) via a gutter, is
suitable only for experienced divers and
perfect weather due to swell conditions.
Rocky Island (North) Conservation Park (9
ha).
Coffin Bay National Park (28,106 ha).
Coffin Bay Conservation Reserve (2,560 ha).
Kellidie Bay Conservation Park (1,780 ha).
Mt Dutton Bay Conservation Park (12 ha).
Agriculture/Industry
There is relatively little urban development
in this biounit. Most adjacent land not
protected as a national or conservation
park, is used for agriculture.
Urban Centres
−
Coffin Bay (population 341). This centre is a
major tourist destination and hence, its
transient population is considerably larger.
Coffin Bay also has a permanent coastal
mooring facility for 90 recreational craft.
Page 70
EYRE REGION – DOUGLAS BIOUNIT
2.6 Significant Cultural and Historical Features
4
AREAS OF HIGH CONSERVATION
VALUE IN THE DOUGLAS BIOUNIT
Aboriginal
Rocky Island (North)
−
−
−
3
Hill Bay, Drummond Point (not dated): an
occupation complex consisting of middens
and artefact scatters.
Has potential for
National Estate listing (A. Nicholson,
pers.comm.).
Although few archeological investigations
have been conducted at Coffin Bay, this
region has the potential to contain a rich and
diverse cultural record (A. Nicholson,
pers.comm.). Further, the relatively intact
character of the natural habitat significantly
increases the integrity of any potential cultural
sites. Coffin Bay is also known to contain
extensive, stone walled fishtraps (Martin
1988). As a result of its cultural significance,
the PALO is presently investigating the
possibility of joint management of this region.
European
Not known.
CURRENT CONSERVATION STATUS
OF THE DOUGLAS BIOUNIT
−
Marine Reserves
None
−
Marine Parks
None
−
−
Netting Closures
Coffin Bay (all waters south of a line from
Point Sir Isaac to Frenchmans Bluff).
Prime IUCN Conservation Values: rare and
endangered species/habitats, biodiversity (IUCN
Category IA). IUCN Identification Criteria:
naturalness (not subjected to human-induced
change, including not subject to human induced
change terrestrial vegetation), ecological
(significant breeding site for New Zealand Fur
Seals and haul out site for Australian Sea
Lions), economic (Southern Rock Lobster,
significant area for Blacklip Abalone), national
(Register of the National Estate-Rocky Island
North Conservation Park),
practicality
(insulation, compatibility-adjacent to Rocky
Island North Conservation Park).
Coffin Bay-Port Douglas-Yangie Bay
−
Prime
IUCN
Conservation
Values:
biodiversity, social, rare and endangered
species/habitats (IUCN Category II). IUCN
Identification Criteria:
naturalness (not
subjected to human-induced change, including
not subject to human induced change terrestrial
vegetation), ecological (significant nursery,
feeding habitat for economic species – eg. King
George Whiting, Western King Prawn, marine
scalefish, significant estuarine function,
ecological integrity, breeding sites for Rock
Parrots, White-bellied Sea Eagles, Ospreys, Red
Capped Plover, Pied Oyster Catcher, Hooded
Plover, Little Penguins, Eastern Reef Egrets,
Crested Terns, Caspian Terns, Fairy Terns,
Sooty Terns), economic (tourism, marine
scalefish fisheries), social (recreation, aesthetic
values), national/international (Wetland of
National Importance-Coffin Bay wetland
system, international importance for shorebirds,
Register of the National Estate-Mt Dutton Bay
Islands Conservation Park), practicality
(accessibility, insulation, compatibility-adjacent
to Coffin Bay National Park, Conservation
Reserve, Mt Dutton Bay Islands Conservation
Park, Kellidie Bay Conservation Park).
Page 71
EYRE REGION – WHIDBEY BIOUNIT
IX
MARINE BIOGEOGRAPHY AND CONSERVATION VALUES OF THE
WHIDBEY BIOUNIT
This biounit extends from Point Sir Isaacs to Cape Catastrophe on the southern tip of Eyre Peninsula, and covers an
area of 132,689 ha and a coastal distance of approximately 167 km. It is oriented in a generally southwesterly
direction into the Southern Ocean.
Gunyah Beach (20 km) is an excellent example of
transgressive Holocene dunes that extend up to 10
km inland. This beach is also the highest energy, and
most dynamic on the Eyre Peninsula.
MARINE BIOGEOGRAPHY
1
OCEANOGRAPHY
The coastline of this biounit faces mostly southwest
and is one of the highest wave energy shorelines in
Australia, rivalling Canunda in the South-East (Short
& Hesp 1984).
Open coast sea temperatures vary from a mean
summer sea surface temperature of 18oC to a mean
winter sea surface temperture of 14oC. The inshore
coastal regions are under the influence of seasonal
coldwater, nutrient-rich coastal upwellings which
occur close to the coast, which can result in an
offshore sea surface temperature gradient of 18oC to
inshore temperatures of 11oC in inshore areas during
the summer months. The major focus of the coastal
upwelling appears to extend from Point Sir Isaac
(Coffin Bay Peninsula) to Cape Borda (Kangaroo
Island) (Wenju et al. 1990) and in part, may be
responsible for the very high levels of productivity,
seabirds, marine mammals, and marine benthic
biodiversity in the region. Recent studies indicate that
is a relationship between the upwellings and the
pilchard abundance in these areas (Ward & McLeay
1998).
2
GEOLOGY
AND
GEOMORPHOLOGY13
COASTAL
This biounit consists of high Pleistocene dune
calcarenite cliffs capped by Holocene clifftop dunes
in places, and high energy intermediate-dissipative
beaches, backed by very unstable massive Holocene
dune transgression usually overlain by Pleistocene
dune calcarenite. Large amounts of marine sediment
have been blown inland by the west to south-west
winds to form some of the widest transgressive
Pleistocene dune calcarenite and Holocene dunes in
Australia.
13
Groper Bay (Sleaford Peninsula) is an excellent
example of the type of steep sand ramps that feed the
successive dune transgressions and cliff top dunes.
A number of offshore islands occur in this biounit:
−
Greenly Island and adjacent islets: composed
of a crystalline basement.
−
Four Hummocks: high domed outcrops of
crystalline basement of granitic composition.
−
Perforated Island: granitic headlands and steep
cliffs which protect small bays and inlets. The
island is composed of crystalline basement
with a thick cover of calcareous aeolianite.
−
Price Island and Liguanea Island: composed of
crystalline basement with a cover of
aeolianite.
−
Curta Rocks: two of the islands are crystalline
basement with a very flat cover of aeolianite.
The others have a very rounded relief.
−
Williams Island: crystalline basement covered
by a thick sequence of calcareous aeolianite.
The crystalline basement outcrops on all but
the eastern coast where near vertical cliffs of
aeolianite rise directly above sea level. There
is one embayment on the northern shore where
beach sand has been deposited.
−
Neptune Islands: North Neptune Island is
crystalline basement with a cover of
calcareous aeolianite with considerable
erosion on the southern and western sides
caused by heavy seas and strong winds. The
three other small islands to the northeast are
crystalline basement. The island nearest to
North Neptune has a thin cover of calcareous
aeolianite.
From Eyre Coast Protection District Study Report.
Page 72
EYRE REGION – WHIDBEY BIOUNIT
−
South Neptune Islands: comprise three islands,
all of which are crystalline basement. The
larger two have an aeolianite cover.
−
On the southwestern coasts of both,
considerable erosion of the aeolianite has
occurred.
−
−
−
−
North and Central Four Hummocks Island).
Rocky Island (South).
Liguanea Island (Cape Carnot).
Curta Rocks, Williams Island (southern
Jussieu Peninsula).
Neptune Islands: including the North Neptune
Islands (4) and the South Neptune Islands (3).
Rivers and Estuaries
3
BIOLOGY
−
Sleaford Mere.
Major Habitats
−
Major intertidal habitats in the region include
mostly offshore islands, sandy beaches and
rocky shores.
MARINE CONSERVATION VALUES
1
−
Of the total inshore subtidal habitats mapped
in the biounit (43,710ha), sandy bottoms
comprise 38,489 ha (88.1%), and reefs
comprise 5,221 ha (11.9%). No seagrass
habitats have been recorded in the region.
SIGNIFICANT BIOLOGICAL AND
PHYSICAL FEATURES
1.1 Biological
Coastal and Marine Wetlands of National
Importance
Major Benthic Communities
−
•
Macroalgal
−
Along the exposed rocky shores, reefs and
islands in this region (eg. Point Whidbey,
Sleaford Bay, Price Island, Four Hummocks,
Liguanea Island), subtidal rocky shore
macroalgal communities are dominated by the
fucoids,
Cystophora
monoliformis,
C.siliquosa, and C.monolifera and the red
algae, Osmundaria and Haliptilon occur in
shallow waters (ie. <5m). In deeper waters,
rocky reef communities are dominated by
Ecklonia radiata and Acrocarpia paniculata
with Osmundaria prolifera with species of
Cystophora (C.platylobium, C.racemosa,
C.moniliformis) as sub-dominants, and also a
wide range of large understorey red algae (eg.
Plocamium, Phacelocarpus, Carpophyllis,
Carpopeltis, Peysonnelia, Sonderopelta) and
green algae (Caulerpa flexilis, C.obscura ).
•
Seagrasses
−
There are no significant areas of seagrasses
within this region, due to the very exposed
nature of the coast.
Coastal and Offshore Islands (or Reefs)
−
−
−
Avoid Bay Islands (including Black Rocks).
Greenly Island and adjacent islets.
Whidbey Islands (Golden, Price, Perforated,
The Coffin Bay coastal wetland system has
been identified as a wetland of national
importance (see ANCA 1996). The Coffin
Bay coastal system encompasses the coastline
of the Coffin Bay Peninsula, including Avoid
Bay and offshore islands, Gunyah Beach,
Seven Mile Beach and the waters of Port
Douglas (including Yangie, Kellidie and
Mount Dutton Bays). See Douglas Biounit for
more information.
Offshore Islands of Recognised Conservation
Significance
−
The offshore islands in this region represent
some of the most significant breeding sites for
the New Zealand Fur Seal (Arctocephalus
forsteri) in Australia. The largest breeding
colonies of fur seals in South Australia occur
on the South and North Neptune Islands and
together have been recently estimated at
almost 16,800 individuals, or 61% of the total
SA population (27,616) or 49% of the
Australian population (34,700) (Shaughnessy
et al. 1994). In this biounit, breeding colonies
of fur seals have been recorded on South
Neptune (1974 pups, estimated population
9,673), North Neptune (1,472 pups, estimated
population 7,212), Liguanea Island (555 pups,
estimated population 2,719), Rocky (South)
Island (75 pups, estimated population 367),
Four Hummock Island (75 pups, estimated
population 367), Greenly Island (11 pups,
estimated population 54) and Little Hummock
Island (7 pups, estimated population 34). Haul
Page 73
EYRE REGION – WHIDBEY BIOUNIT
out and basking sites include South Neptune
Island (South), Low Rocks, Williams Island,
Curta Rocks, Cape Rock, Four Hummocks
(South, Mid, North), Rocky (North) Islands
(Shaughnessy et al. 1994).
−
Colonies of the rare Australian Sea Lions
(Neophoca cinerea) have also been recorded
on many offshore islands in this region.
Although breeding takes place at only some of
these sites there is considerable mobility
between haul out sites. Breeding colonies
have been recorded on Liguanea Island (30
pups, estimated population 144) and South
Neptune Island (North) (4 pups, estimated
population 19). While breeding possibly
occurs on Rocky Island (North and South),
Greenly Island, North Hummock, Price, East
Neptune Islands (Gales 1990). Haul out and
basking sites in this region include South
Hummock, Central Hummock, Little NE
Hummock, Golden, Cape Rock, Curta Rocks,
Williams, Low Rocks, West Neptune and
North and South Neptune Islands (Watts &
Ling 1985, Gales et al. 1994).
•
Avoid Bay Islands Conservation Park.
−
This is another important area for birdlife,
although only Black Rocks have been
surveyed by the National Parks and Wildlife
Service. Species include White-faced Storm
Petrels, Pelagodroma marina, Little Penguins,
and Short-tailed Shearwaters, Puffinus
tenuirostris. A pair of White-bellied Sea
Eagles, Haliaeetus leucogaster, nest regularly
on one of the rocky stacks off Black Rocks;
Rock Parrots (Neophema petrophila) are also
very common and probably breed here. The
islands are on the Register of the National
Estate.
•
Whidbey Islands Conservation Park
−
Is a group of spectacular and relatively
pristine islands. Small numbers of Cape
Barren Geese breed on these islands as well as
small breeding populations of Short-tailed
Shearwaters. Many of the islands are also
significant breeding and haul out sites for
Australian Sea Lions and New Zealand Fur
Seals (see above). Perforated Island, so
named by Matthew Flinders for the large hole
eroded through the middle of the island, has
aeolianite cliffs rising sheer from a water level
platform of granite.
There are dense
population of Southern Bush Rats and large
numbers of Short-tailed Shearwaters on the
island. The islands are on the Register of the
National Estate.
•
Greenly Island Conservation Park
−
Is a spectacular granite dome with steep sides
plunging straight into deep water. It is split by
two large crevasses which effectively break
the island up into three blocks.
There
populations of Bush Rats and Cape Barren
Geese on the island. There is also a breeding
colony of New Zealand Fur Seals
(Shaughnessy 1990) and a possible breeding
colony of Australian Sea Lions (Gales 1990).
The island is on the Register of the National
Estate.
•
−
Rocky Island (South) Conservation Park:
A small but significant breeding colony
(approximately 367 individuals) of the New
Zealand Fur Seal (Arctocephalus forsteri) has
been
recorded
on
Rocky
(South)
(Shaughnessy et al. 1994). Haul out and
possibly breeding colonies of the rare
Australian Sea Lions (Neophoca cinerea)
occur on Rocky Island (South) (Watts & Ling
1985, Gales 1990). The park is on the
Register of the National Estate.
Other Areas of Recognised Conservation
Significance
•
Lincoln National Park
−
This park includes most of the Jussieu
Peninsula, together with the following
offshore islands: Rabbit, Bickers, Owen,
Little, Lewis, Hopkins, Smith, Albatross,
Curta Rocks and Liguanea. All of the islands
support very large breeding populations of
Short-tailed
Shearwaters
(Puffinus
tenuirostris).
Smith Island supports a
breeding colony of the Flesh-footed
Shearwater (Puffinus carneipes), discovered
only recently in 1982. On Curta Rocks there
are large breeding colonies of the White-faced
Storm Petrel (Pelagadroma marina). Islands
and mainland coast support significant
breeding populations of the White-bellied Sea
Eagles (Haliaeetus leucogaster) and Ospreys
(Pandion haliaetus). Many of the islands in
this group support breeding or haul out sites
for New Zealand Fur Seals and rare Australian
Sea Lions (Neophoca cinerea) (see above).
Page 74
EYRE REGION – WHIDBEY BIOUNIT
•
Sleaford Mere Conservation Park
−
Is a shallow coastal brackish lake, which
contains several small islands. Of particular
biological significance is the occurrence of
stromatolites, up to one metre across, and also,
the existence of a land-locked population of
skates.
1.2 Physical
Geological Monuments
−
The coastal outcrops of old Precambrian rocks
on southern (and southeastern) Eyre Peninsula
are geologically of international significance.
Of particular significance is the region from
Whalers Way-Fishery Bay to Cape Carnot
which consists of spectacular calcreted
aeolianite
cliffs
on
a
Precambrian
metamorphic basement. Cape Carnot itself
has been recognised as a "geological
monument" of international significance and is
also on the Register of National Estate.
−
Cape Catastrophe: charnockitic rocks.
2
OTHER VALUES
2.1 Commercial Fisheries
Major single species fisheries include Southern Rock
Lobster and Abalone. Marine scalefish fisheries
target King George Whiting.
Southern Rock Lobster
This biounit represents a significant region for
lobster fishing in South Australia. In 1995/96 and
1996/97 a total of 47 and 40 licensed operators
fished in the inshore waters of the Whidbey Biounit
(ie. Fishing Zone 28), catching approximately
141,100 and 177,186 kg of lobsters,
respectively (or 2.76% and 3.46% of the total catch
for Southern Rock Lobster in South Australian
waters). In contrast, in the offshore southern
waters of this biounit (ie. Fishing Zone 38), there is
less activity and production. During 1995/96 and
1996/97, a total of 19 and 16 licensed operators
fished in the offshore waters of the Whidbey
Biounit (ie. Fishing Zone 38), catching
approximately 13 783 and 10 796 kg of lobsters,
respectively (or 0.27% and 0.21% of the total catch
for Southern Rock Lobster in South Australian
waters). In the offshore western waters of this
biounit (ie. Fishing Zone 26), there is a similar
level of fishing activity. During 1995/96 and
1996/97, a total of 20 and 20 licensed operators
fished in the offshore western waters of the biounit
(ie. Fishing Zone 26), catching approximately 11
751 and 16 699 kg of lobsters, respectively (or
0.23% and 0.33% of the total catch for Southern
Rock Lobster in South Australian waters).
Abalone
The Whidbey Biounit is a major region for both,
the Blacklip Abalone and Greenlip Abalone fishery
in South Australia. In 1994/95 and 1995/96 a total
of 32,064 and 36,168 kg of Greenlip was harvested
within this region (ie. MapCode 13D-F, 14A-F,
15A-B, 16A-C, 17A-B, 18A-B Point Sir Isaac to
Cape Catastrophe, including Whidbey Isles, Avoid
Bay Isles), and represented 14.1% and 16.0% of the
total Greenlip Western Zone catch (or 8.51% and
9.66% of the total catch for Greenlip in South
Australian waters). In 1994/95 and 1995/96 a total
of 51,828 and 38,563 kg of Blacklip was harvested
within this region, and represented 16.7% and
13.9% of the total Blacklip Western Zone catch (or
10.49% and 8.33% of the total catch for Blacklip in
South Australian waters).
Within this region, some abalone is also harvested
at the Neptune Islands. In 1994/95 and 1995/96 a
total of 7,317 and 687 kg of Greenlip was
harvested around the Neptune Islands (ie.
MapCode 17C), and represented 3.2% and 0.3% of
the total Greenlip Western Zone catch (or 1.94%
and 0.18% of the total catch for Greenlip in South
Australian waters). In 1994/95 and 1995/96 a total
of 1041 and 0 kg of Blacklip was harvested within
this region, and represented 0.3% of the total
Blacklip Western Zone catch in 1994/95 (or 0.21%
of the total catch for Blacklip in South Australian
waters).
Marine Scalefish Fisheries
This biounit, particularly the offshore waters (ie.
Fishing Zone 38), represents a significant region
for fin fishing in South Australia. During 1995/96
and 1996/97, 24 and 21 commercial licence holders
(made up of Marine Scalefish, Restricted Marine
Scalefish and Northern Zone Rock Lobster licence
categories) caught commercial marine scalefish
species from the inshore waters of the Whidbey
Biounit (ie. Fishing Zone 28), respectively.
License holders expended approximately 631 and
529 boat days effort fishing these waters during
1995/96 and 1996/97, respectively. The marine
scalefish catch for this region (ie. Fishing Zone 28)
represented 39,327 kg in 1995/96 and 78 148 kg in
1996/97(or 0.38% and 0.77% of the total catch for
the marine scalefish fishery in South Australian
waters).
Page 75
EYRE REGION – WHIDBEY BIOUNIT
In the offshore southern waters of this biounit (ie.
Fishing Zone 38), there is less activity and
production. During 1995/96 and 1996/97, a total of
12 and 16 licensed operators fished for 371 and 346
days in the offshore waters of the Whidbey Biounit
(ie. Fishing Zone 38), catching a total of 352,473
and 310,781 kg, respectively (or 3.39% and 3.07%
of the total catch for the marine scalefish fishery in
South Australian waters). In the offshore western
waters of this biounit (ie. Fishing Zone 26), there is
a significantly reduced level of fishing effort and
productivity. During 1995/96 and 1996/97, a total
of 9 and 13 licensed operators fished for 204 and
331 days in the offshore western waters of the
biounit (ie. Fishing Zone 26), catching a total of
150,812 and 196,324 kg, respectively (or 1.45%
and 1.94% of the total catch for the marine
scalefish fishery in South Australian waters).
−
Farm Beach: boat fishing. Major species:
King George Whiting, Sand Flathead, Tommy
Rough and Garfish.
Tourism
−
Neptune Islands: well known as an area for
filming and watching White Sharks. The
islands are generally reached by boat charter.
−
Offshore islands: popular sites for SCUBA
diving and fishing, including the collecting of
Abalone and Southern Rock Lobster.
−
Whalers Way: contains some of the most
accessible, dramatic and beautiful coastal
scenery in South Australia. The variety of
coastal scenery includes cliffs, caves,
crevasses, blowholes and beaches.
Although license holders are not restricted to fishing
in this biounit, the following licenses are registered in
this area:
2.4 Scientific Research and Education
−
Coffin Bay: 7 unrestricted marine scalefish
licenses, 4 Southern Rock Lobster.
−
Researchers from the NPWS regularly
conduct surveys of Australian Sea Lion and
New Zealand Fur Seal colonies in this region,
particularly on offshore islands such as the
Neptune Islands.
−
The Neptune Islands is becoming well-known,
both nationally and internationally as one of
the major sites in the world for research into
White Sharks (Carcharodon carcharias).
There is presently an ongoing tagging project
being conducted jointly by fisheries
researchers and researchers from the
international, Cousteau Society.
−
Fisheries research in this area includes, regular
catch and effort monitoring of the major
commercial fisheries in the region (Abalone,
Southern Rock Lobster, Western King Prawn,
and marine scalefish); regular research and
monitoring of larval fish stocks; regular
research and monitoring of Blacklip and
Greenlip Abalone field stocks; and regular
research and monitoring of South Rock
Lobster field stocks.
2.2 Aquaculture
No marine-based aquaculture current exists in the
Point Sir Isaac to Cape Catastrophe region. The
Lower Eyre Peninsula Aquaculture Management
Plan (Aquaculture Group, PIRSA 1997) proposes no
aquaculture development in this region:
Avoid Bay Policy Area
−
Avoid Bay Zone (Point Sir Isaac to Shoal
Point, including Avoid Bay Isles, Whidbey
Isles) – licenses will not be considered for
aquaculture development in this zone.
Cape Carnot Policy Area
−
Cape Carnot Zone (Shoal Point to Cape
Catastrophe, including Liguanea Island) licenses will not be considered for aquaculture
development in this zone.
2.3 Recreation and Tourism
Fishing
−
Convention Beach: beach fishing. Major
species: Sand Flathead, Yelloweye Mullet,
Australian Salmon and Tommy Rough.
2.5 Adjacent Land Use
National and Conservation Parks
−
Coffin Bay National Park (28,106 ha).
−
Avoid Bay Islands Conservation Park (16 ha).
Page 76
EYRE REGION – WHIDBEY BIOUNIT
−
−
Ellis’ (which has been located); the `Amelia’
which is located in Avoid Bay; the HMS
`Investigator’ cutter near Cape Catastrophe;
and possibly one or two whaler’s anchors in
Fishery Bay.
Whidbey Islands Conservation Park (271 ha):
includes, from the Coffin Bay Peninsula,
Golden, Price, Perforated, North and Central
Four Hummocks Island.
Greenly Island Conservation Park (190 ha).
−
Rocky Island (South) Conservation Park (4
ha).
−
Lincoln National Park (29,060 ha): includes
most of the Jussieu Peninsula, together with
the following offshore islands: Rabbit,
Bickers, Owen, Little, Lewis, Hopkins, Smith,
Albatross, Curta Rocks and Liguanea.
−
Lincoln Conservation Reserve (308 ha).
−
Sleaford Mere Conservation Park (697 ha).
Agriculture/Industry
3
−
Marine Reserves
None
−
Marine Parks
None
−
Netting Closures
None.
4
There is no urban development in this biounit.
Most adjacent land not protected as a national or
conservation park, is used for agriculture.
Urban Centres
None.
CURRENT CONSERVATION STATUS
OF THE WHIDBEY BIOUNIT
AREAS OF HIGH CONSERVATION
VALUE IN THE WHIDBEY BIOUNIT
Coffin Bay National Park-Avoid Bay-Avoid
Bay Isles
−
−
The Lincoln National Park is significant in the
history of South Australian exploration
through its association with the voyage of
Matthew Flinders in 1802. A memorial on
Stamford Hill in the park commemorates
Flinders' visit to the area while the Cape
Catastrophe, Memory Cove area was the scene
of the most tragic incident of Flinders'
circumnavigation of Australia.
−
An old whaling station is located at Sleaford
Bay.
Prime
IUCN
Conservation
Values:
biodiversity,
rare
and
endangered
species/habitats, aesthetics (IUCN Category IB).
IUCN Identification Criteria: naturalness (not
subjected to human-induced change, including
not subject to human induced change terrestrial
vegetation), ecological (ecological integrity,
significant breeding site for New Zealand Fur
Seals
and
Australian
Sea
Lions,
breeding/roosting sites for White-faced Storm
Petrels, Little Penguins,
Short-tailed
Shearwaters, White-bellied Sea Eagles,
Ospreys, Rock Parrots, Red Cap Plover, Pied
Oyster Catcher, Hooded Plover), economic
(Southern Rock Lobster, significant area for
Blacklip Abalone), social (aesthetic values,
historic shipwrecks-`Amelia’) national (Wetland
of National Importance-Coffin Bay wetland
system, international importance for shorebirds,
Register of the National Estate), practicality
(insulation, compatibility-adjacent to Coffin Bay
National Park, Conservation Reserve and Avoid
Bay Islands Conservation Park).
Shipwrecks
Whidbey Islands
−
2.6 Significant Cultural and Historical Features
−
Aboriginal
Not known.
European
−
As yet, no shipwrecks within the State waters
of southern Eyre Peninsula have been declared
historic (under the Historic Shipwrecks Act
1981). However, three shipwrecks and some
whaler’s anchors older than 75 years are
located in Commonwealth waters and are
protected under the Commonwealth legislation
(ie. Historic Shipwrecks Act 1976): the `Mary
−
Prime IUCN Conservation Values: rare and
endangered species/habitats, biodiversity (IUCN
Category 1A). IUCN Identification Criteria:
naturalness (not subjected to human-induced
change), ecological (breeding and haul out sites
for New Zealand Fur Seals-Rocky South, Four
Hummock, Little Hummock, breeding and haul
out sites for Australian Sea Lions-North
Page 77
EYRE REGION – WHIDBEY BIOUNIT
Hummock, South Hummock, Central Hummock,
Little NE Hummock, Price, Golden, Cape Rock,
breeding sites for Cape Barren Geese, Shorttailed Shearwaters, Southern Bush Rat),
economic (Southern Rock Lobster, Blacklip
Abalone), national (Register of the National
Estate-Whidbey Islands Conservation Park),
practicality (insulation, compatibility- adjacent
to Whidbey Islands Conservation Park).
Greenly Islands
−
Prime IUCN Conservation Values: rare and
endangered species/habitats, biodiversity (IUCN
Category 1A). IUCN Identification Criteria:
naturalness (not subjected to human-induced
change), ecological (breeding site for New
Zealand Fur Seals and Australian Sea Lions,
breeding sites for Little Penguins, Fairy Tern,
Short-tailed Shearwater, roosting sites for
White-bellied Sea Eagle, Cape Barren Geese,
Southern Bush Rat), economic (Southern Rock
Lobster), national (Register of the National
Estate), practicality (insulation, compatibilityadjacent to Greenly Islands Conservation
Park).
Rocky Island (South)
−
Prime IUCN Conservation Values: rare and
endangered species/habitats, biodiversity (IUCN
Category IA). IUCN Identification Criteria:
naturalness (not subjected to human-induced
change), ecological (significant breeding site for
New Zealand Fur Seals and haul out site for
Australian Sea Lions), economic (Southern
Rock Lobster, Blacklip Abalone), national
(Register of the National Estate), practicality
(insulation, compatibility-adjacent to Rocky
Island South Conservation Park).
Lincoln National Park-Thorny Passage
−
Prime IUCN Conservation Values: rare and
endangered
species/habitats,
aesthetics,
biodiversity, cultural values (IUCN Category
IB).
IUCN Identification Criteria:
naturalness (not subjected to human-induced
change), biogeographic (geological monument –
Cape Catastrophe, Memory Cove, Cape
Donington), ecological (significant breeding
and haul out sites for New Zealand Fur SealsLiguanea Island, Low Rocks, Albatross Island,
Williams Island, Curta Rocks, Cape Rock,
breeding and haul out sites for Australian Sea
Lions-Liguanea Island, Curta Rocks, Cape
Rock, Williams, Smith, Little, Hopkins, Lewis,
Thistle, Albatross Islands, White Shark
populations, breeding sites for Short-tailed
Shearwater, Flesh-footed Shearwater, Whitefaced Storm Petrel, White-bellied Sea Eagle,
Ospreys), economic (tourism-dive and fishing
charters, significant area for Greenlip Abalone,
Blacklip Abalone, Southern Rock Lobster),
social (recreation, aesthetic values, whaling
stations-Thistle Island, Sleaford Bay, Memory
Cove,
historic
shipwrecks-`Investigator’),
national (national importance of breeding
colonies of New Zealand Fur Seals and
Australian Sea Lions, Register of the National
Estate-Lincoln National Park), practicality
(accessibility, insulation, compatibility-adjacent
to Lincoln National Park, Sleaford Mere
Conservation Park).
Cape Carnot-Cape Wiles-Fishery Bay
−
Prime IUCN Conservation Values: social,
aesthetics, biodiversity (IUCN Category III).
IUCN Identification Criteria: naturalness (not
subjected
to
human-induced
change),
biogeographic
(geological
monument),
ecological economic (tourism, Southern Rock
Lobster), social (Whalers Way-very high
aesthetic
coastal
values,
recreation),
national/international (Register of the National
Estate, Geological Monument of International
Significance-Cape Carnot).
Page 78
SPENCER GULF REGION
MARINE BIOGEOGRAPHY AND CONSERVATION VALUES OF SPENCER GULF
MARINE BIOGEOGRAPHY
1.
2.
3.
4.
5.
Spencer Gulf
Oceanography
Climate
Coastal Geomorphology and Landforms
Biology
MARINE CONSERVATION VALUES
1.
2.
3.
Significant Biological and Physical Features
Significant Cultural and Historical Features
Current Conservation Status of Spencer Gulf
BIOUNITS
1.
2.
3.
4.
5.
6.
7.
8.
9.
Jussieu
Dutton
Franklin
Yonga
Winninowie
Tiparra
Wardang
Pondalowie
Gambier
Page 79
SPENCER GULF REGION
MARINE BIOGEOGRAPHY AND CONSERVATION VALUES OF SPENCER GULF
MARINE BIOGEOGRAPHY
1
SPENCER GULF
Spencer
Gulf
falls
within
the
coastal
geomorphological region known as the Gulfs
Province (Short et al. 1986). This region extends
from Cape Catastrophe, on the south eastern tip of
Eyre Peninsula, to Rapid Head on the Fleurieu
Peninsula, and includes South Australia's other large
sheltered gulf ecosystem; Gulf St Vincent. Within
these sheltered gulf waters occur some of the largest
temperate seagrass ecosystems in the world. The
sheltered waters also provide an ideal habitat for
extensive, intertidal forests of the Grey Mangrove,
most of which occur in this region. Together, these
coastal ecosystems are of immense ecological and
economic importance, providing the essential basis
for much of South Australia's commercial and
recreational fisheries. The coastal areas of the gulfs
however, also support the major urban and industrial
cities of South Australia. Historically, this province
is also of the greatest maritime significance,
reflecting essentially the early European settlement of
this region. However, present and future urban and
industrial activity in this province, also places this
region under the greatest threat from human activity.
1.1
Biogeography of Spencer Gulf
Along the southern coast of Australia, marine
biogeographers recognise a major biogeographic
region, known as the Flindersian Province, which
extends from south-west Western Australia to
southern New South Wales and includes the waters
of Victoria and Tasmania. Within this broad
region, the coastal waters of the Great Australian
Bight are recognised as warm to cool temperate (in
contrast to the cold temperate waters of the southeast of Australia, west of Robe).
A complete physical and ecological biogeographic
description of the Eyre, Spencer Gulf and Northern
Spencer Bioregions, including marine fauna and
flora, has been described by IMCRA (1997).
Based on coastal geology, wave climate, and
coastal orientation, (Short et al. 1986), identified
the following coastal geomorphological regions (or
subprovinces) for the Spencer Gulf region:
1
2
3
4.
5
6
Based on patterns of biogeography and marine
habitats
(and
also,
existing
coastal
geomorphological classifications), a total of 10
marine biounits have been recognised for the
Spencer Gulf region:
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
2
Within the Flindersian Province, the Spencer Gulf
region (including the Sir Joseph Banks, Gambier
and Neptune Isles) encompasses 3 well-defined,
finer-scale biogeographical regions: the Eyre
Bioregion (which extends from Point Labatt to
Arno Bay, and Cape Borda to West Cape); the
Spencer Gulf Bioregion (which extends from Arno
Bay to Corny Point, and Shoalwater Point to Point
Reilly); and the Northern Spencer Gulf Bioregion
(which extends from Shoalwater Point to Port
Augusta, to Point Reilly) (IMCRA 1997).
Southwest Spencer Gulf Subprovince (from
Cape Catastrophe to Salt Creek, Tumby Bay,
191 km).
Southern Spencer Gulf Subprovince (from Salt
Creek to Germein Point, 114 km).
Central Spencer Gulf Subprovince (Germein
Point to 40 km north of the Hd of Mcgregor
boundary, Whyalla, 61 km).
Northern Spencer Gulf Subprovince (from
Whyalla to Tickera).
Wardang Subprovince (from Tickera to Point
Turton, 170 km).
Formby Bay Subprovince (from Point Turton
to West Cape, 80 km).
2.1
Jussieu Biounit Dutton Biounit Franklin Biounit Yonga Biounit Wininnowie Biounit –
Tiparra Biounit Wardang Biounit –
Pondalowie Biounit
Banks Biounit –
Gambier Biounit
OCEANOGRAPHY
Wave Climate
Wave energy in Spencer Gulf ranges from
moderate at the mouth of the gulf, to very low in
the upper regions. Overall, the gulf is a very
sheltered ecosystem, subject to very low to low
wave energy regimes.
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SPENCER GULF REGION
Tides in Spencer Gulf are semi-diurnal with spring
ranges of 3.1 m at Whyalla, 3.5 m at Port Pirie and
3.9 m at Port Augusta. There are also considerable
changes in mean sea level caused by barometric
pressure variations and wind stress, with periods of
between 1 and 365 days. These mean sea-level
oscillations are relatively slow and can, therefore,
penetrate into the northern regions of Spencer Gulf,
potentially increasing astronomical tides by over 2
m.
Storm surges of up to 1 m are also possible due to
the effects of strong winds. These effects become
more pronounced in the upper gulf waters due to a
`funnelling effect'.
In both Spencer Gulf and Gulf St Vincent, a regular
period of minimal tidal movement occurs, called a
`dodge tide'.
In Spencer Gulf, this occurs
fortnightly (Gostin et al. 1984).
2.2
CLIMATE
The climate of Spencer Gulf is typically semi-arid
or `Mediterranean' and as such, is characterised by
hot, dry summers and cool, moist winters. It is
largely influenced by mid-latitude anticyclones or
high pressure systems which pass from west to east
across the continent. Winter generally brings
southerly to southeasterly winds and low pressure
systems which travel across the Southern Ocean
between 40 and 50oS, bringing frontal activity and
rain. Summer brings northerly to northwesterly
winds. Spencer Gulf itself has an ameliorating
effect on the coastal regions, producing more
temperate weather. The prevailing wind patterns
are also influenced by the gulf.
Most rainfall falls during winter, however it varies
considerably with latitude, from approximately 500
mm in the south to less than 300 mm in the north.
Water Temperature and Salinity
Spencer Gulf is a hypersaline-high water
temperature ecosystem, also referred to as a
`reverse estuary', because waters of highest
salinities and temperatures occur at the `head' or
upper reaches of the gulf, rather than near the open
ocean.
Salinity and temperature ranges increase from 42.044.8%. and 11.0-240C, at Point Lowly, to 43.248.6%. and 260C, respectively, near Port Augusta
(Johnson 1981).
This salinity increase is
essentially a result of evaporative and mixing
processes. Across the entrance of the gulf, salinity
and temperature values also vary annually and
seasonally, between 35.7 and 37.3%. and 13.00C
and 18.00C, respectively. This results in an
increase in salinity and temperature from west to
east across the entrance of Spencer Gulf (Bullock
1975, Bye & Whitehead 1975).
2.3
3
Currents
In Spencer Gulf, a northward flowing current
originating from the Bight region enters the
western side of the gulf.
Branches of this
northward flowing current are deflected southward
in the Tiparra Reef area, forming a southward
flowing counter current along the opposite shore.
This counter current generally has higher salinities,
resulting in the salinity gradient found at the
entrance of the gulf.
4
COASTAL GEOMORPHOLOGY
LANDFORMS
AND
The east coast of Eyre Peninsula is considerably
different to the west, being lower and sheltered
within Spencer Gulf (see Short et al. 1996, for
review). The coast is backed by plains underlain
by alluvium and alluvial fans, with the same
alternations of headland and bay that occurs on the
west coast. The rocky headlands typically consist
of exposed Precambrian crystalline rocks, while the
beaches have coastal dunes developing behind
them. The lower or southern sections of Spencer
Gulf, in particular, is highly variable in coastal
morphology, and is subdivided by 5 large
embayments (Boston, Proper, Porter, Louth, Peake)
and 2 large peninsulas (Bolingbroke, Jussieu).
Within Spencer Gulf waters there are 31 offshore
islands, half of which occur in the Sir Joseph Banks
Group near Port Lincoln. The remainder are
located between Thistle Island, the largest of the
Eyre Peninsula islands (40 km2), and the mainland.
In many places shell beds and typical sandy beach
deposits are found well above present day high
water mark, indicating a period when sea level was
higher than it is today. On the west coast of Yorke
Peninsula a well marked raised beach is found at
Point Brown.
In both gulfs, the major tidal currents carry fine,
suspended sediment which settle out in the upper
reaches, effectively creating very large sedimentary
basins.
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SPENCER GULF REGION
The west coast of Yorke Peninsula is more
irregular than the east, and consequently a few
more bays have developed at Moonta Bay, Port
Victoria and Hardwicke Bay. Cliffs are not
common, although resistant headlands composed of
hard granitic rocks do occur at Pearce Point and
along the west coast of Wardang Island. A series
of beach dune ridges built up during former high
still stands of the sea are particularly well
developed east of Point Turton and also near Port
Victoria and Cape Elizabeth. There are even more
extensive ridges on the northern coast of the foot.
The coasts along the `foot' of Yorke Peninsula
show strong evidence that vigorous erosion is
occurring, due primarily to strong prevailing winds
and associated storm waves coming from the
Southern Ocean. The influence of bedrock on
landscape development can be clearly seen, and all
the prominent headlands are formed of hard
resistant granitic rocks eg. Corny Point, Daly Head
and Point Yorke.
5
5.1
BIOLOGY
General Marine Ecology
The large, sheltered, tidal, reverse estuary of Spencer
Gulf , supports some of the most extensive seagrass,
mangrove and tidal saltmarsh communities in South
Australia (Edyvane 1995). A diverse range of coastal
and habitats are represented within Spencer Gulf,
including: extensive forests of the grey mangrove and
their associated samphire and mudflat habitats in
sheltered locations; seagrass meadows; estuaries;
intertidal rocky reefs; sandy beaches, subtidal sand
patches and “megaripples”; offshore islands; subtidal
reefs; and benthic faunal beds on muddy substrates
(Edyvane 1995). The major assemblages and
communities are broadly distributed according to
depth, wave exposure and tidal currents, although
local variations occur.
Spencer Gulf, particularly the northern reaches,
support the most extensive seagrass meadows in
South Australia. Approximately 5512 km2 of the
seagrass (or 57% of the total area of seagrasses
recorded in South Australia), have been recorded in
Spencer Gulf region, making it one of the largest
areas of temperate seagrass meadows in Australia.
These extensive seagrass meadows flourish in the
shallow waters of the gulf, generally in waters less
than 10m, and provide the basis for the significant
productivity of the gulf in terms of fisheries
production. The seagrass meadows also support a
prolific skeletal biota as infauna and epiphytes, which
in turn, provides the carbonate basis for the sediments
in the region.
The Spencer Gulf region also contains the most
extensive areas of mangrove forests in South
Australia (Edyvane 1995). Forests occur north of
Point Lowly, Port Pirie to Port Broughton, Franklin
Harbour, and to a lesser extent at Tumby Bay.
Associated with the mangrove habitats are extensive
biologically rich mud flats, samphires and seagrasses.
5.2 Intertidal Ecology
The intertidal ecology of Spencer Gulf has been
summarised in general accounts of the marine
intertidal ecology of South Australia, by Womersley
and Edmond (1958), and more recently be
Womersley (1990). On coasts of moderate wave
energy, such as the southern coasts of Spencer Gulf,
the intertidal and subtidal fringe of rocky shores is
dominated by the brown algae Hormosira banksii
and Cystophora spp. On rocky coasts with some
wave action, the upper sublittoral zone is dominated
by large brown algae, especially Ecklonia radiata,
Cystophora subfarcinata, C.retorta, C.polycystidea,
C.moniliformis and other species; Caulocystis
cephalornithos; Cystoseira trinodis; and Sargassum
spp. (such as S.decipiens and S.lacerifolium), with an
understorey of coralline algae (e.g. Amphiroa anceps,
Cheilosporum elegans), Cladostephus spongiosus
and species of Caulerpa. On sandy bottom, below
rock areas, the seagrasses Amphibolis and Posidonia
often cover very extensive areas as dense, and
usually pure, communities.
On coasts of slight wave action, with sandy or muddy
flats or beaches (ie. the northern parts of Spencer
Gulf, excluding rocky outcrops, and several almost
land-locked bays, eg. Franklin Harbour), the
intertidal and sublittoral fringe is dominated by
samphires, the grey mangrove Avicennia marina, the
brown alga Hormosira banksii, Pinna razor fish and
the filamentous red algae Hypnea and Spyridia.
Common algae which occur just below low tide level
include Hypnea sp., Spyridia filamentosa, and the
green algae Ulva sp., Enteromorpha, Cladophora
and Polyphysa peniculus, the latter of which grows
epiphytically on old cockle shells.
The intertidal forests of the grey mangrove
(Avicennia marina) in northern and central Spencer
Gulf are the most extensive in South Australia.
Mangrove forests occur north of Point Lowly, Port
Pirie to Port Broughton, Franklin Harbour, and to a
lesser degree near Tumby Bay in Spencer Gulf.
Associated with the mangrove habitats are the
biologically rich mud flats, samphires and seagrasses.
At Redcliff, monospecific stands of Avicennia
marina form a low woodland forest extending from
mean sea level to spring high-tide level.
Progressively higher vegetated zones are a
Halosarcia-Sarcocornia (samphire) association, a
Sclerostegia-Halosarcia (samphire) association and
an Atriplex (saltbush) association (Chinnock 1980).
Conspicuous algal mats, which form as a result of
sediment trapping by filamentous blue-green algae
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SPENCER GULF REGION
are associated with both the mangrove and samphire
flora. A variety of marine organisms, mostly
gastropods, bivalves, polychaetes and crustaceans,
live in and on the mangrove mud, including a newly
described species of barnacle (Bayliss 1994).
5.3
Subtidal Ecology1
Spencer Gulf has a wide variety of subtidal benthic
habitats, from the invertebrate-dominated muddy
benthic environments (fringed with extensive
mangrove ecosystems) in much of the far northern
gulf, to the seagrass meadows of various densities,
sand patches, and algal-dominated platform reefs
scattered throughout the central and southern parts
of the gulf. Much of southern Spencer Gulf, such as
the foot of Yorke Peninsula, comprises strong
seasonal currents, which support great abundance
and diversity of reef floral species (Edyvane and
Baker 1996).
Mixed substrates of calcareous reef and sand are
found in some areas, supporting both seagrass
meadows and algal forests, such as Daly Head
(south-eastern Spencer Gulf -Yorke Peninsula) and
Port Neill (middle western Spencer Gulf).
Calcareous reef is also a dominant benthic feature
at Wardang Island and Point Riley, in the upper
middle part of eastern Spencer Gulf. Small patches
of flat platform reef with overlying sand occur
from Shoalwater Point to Arno Bay (middle
western Spencer Gulf). Heavy calcareous reef also
outcrops off Warbuton Point (north of Moonta Bay,
eastern Spencer Gulf), and from the Reef
Point/Point Pearce area, out to, and including,
Wardang Island. South of Wardang Island,
platform reef occurs from the coast westwards, and
southwards to the eastern end of Hardwicke Bay.
Much of the “foot” of Yorke Peninsula comprises
heavy calcareous reef (eg. from Daly Head around
to Stenhouse Bay).
Sandy areas (colonised by seagrass) include much
of northern Spencer Gulf (eg. sandy channels off
Middle Bank and Two Hummock Point) and the
large sheltered embayments of Hardwicke Bay and
Port Minlacowie in south eastern Spencer Gulf; and
Tiparra Bay.
Northern Spencer Gulf
The subtidal benthic habitats of northern Spencer
Gulf have been the subject of several surveys, the
most notable including Shepherd and Branden
(1973), Shepherd (1974) and Shepherd (1983a,b).
These studies examined the benthic assemblages of
the Middle Bank area (Shepherd & Branden 1973),
Crag Point (Shepherd 1974), and the Middle Bank Douglas Bank region (Shepherd 1983a, b). The
surveys recorded the presence of dense,
1
From Edyvane KS & JL Baker (1996). Marine Biogeography of
Spencer Gulf.
monospecific stands of seagrasses in the region,
including,
Amphibolis
antarctica,
Posidonia australis and P. sinuosa as the
main floral components of the benthos,
with scattered stands of Heterozostera
tasmanica, Halophila ovalis and Caulerpa
cactoides between 7 and 10m depth.
Several animal assemblages dominated the
benthos
including
a
mixed
sponge/cnidarian/echinoderm assemblage
on rocky and consolidated shelly substrate;
a bryozoan/ascidian/sea pen (Lanceopora,
Scyozoa, Polycarpa) assemblage in the
troughs of sand waves or “megaripples”
(Shepherd
1983b),
and
molluscan
aggregations comprising hammer oysters
(Malleus) and razorfish (Pinna bicolor),
which occurred over a broad depth range
(between the intertidal and 16m depth).
The benthic flora and fauna of northern Spencer gulf
is characterised by a significant and very distinctive
relict tropical element (Shepherd 1983, Edyvane
1995). For this reason it has been identified as a
distinctive biogeographical region, known as the
Northern Spencer Gulf Bioregion (Edyvane & Baker
1995, IMCRA in press). Although most of the algal
species recorded in northern Spencer Gulf have
intermediate warm to cool temperate affinities
(occurring throughout the southern Australian
region), some algal species, such as the brown
macroalgae Hormophysa triqueta and Sargassum
decurrens, are distinctly tropical and sub-tropical in
distribution (Shepherd 1983). Notwithstanding, other
algal species, such as Asparagopsis taxiformis and
Platysiphonis mutabilis, appear to have distinct warm
temperate affinities, occurring only westward of the
South Australian Gulfs. In addition to these species,
Beanland & Woelkerling (1982) recorded a further
four algal species, with tropical affinities, on
mangrove pneumatophores. Shepherd (1983), in his
survey of northern Spencer Gulf, also recorded a
number of coelenterates of special interest. These
included: Echinogorgia sp. and Scytalium sp. which
appear to be endemic in upper Spencer Gulf
(Grasshoff 1982, Shepherd 1983);
Virgularia
mirabilis, a cosmopolitan species, known in South
Australia only from this region (Utinomi & Shepherd
1982, Shepherd 1983); and Telest multiflora, a
tropical species, which has been recorded only from
mid and upper Spencer Gulf in southern Australia
(Verseveldt 1982, Shepherd 1983). In addition, the
ascidian, Sucozoa pedunculata is known in southern
Australian only from upper Spencer Gulf and
Investigator Strait (Kott 1972, 1975). These last four
species except for V.mirabilis, appear to have tropical
affinities suggesting that isolated populations are
confined to Gulf waters (Shepherd 1983). In
addition, Shepherd (1983) recorded a number of
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SPENCER GULF REGION
species in other phyla newly or not yet described,
which are known only from upper Spencer Gulf
region. They include the bryozoan, Bugula sp., a
flatworm, Ancoratheca australiaensis and an
opisthobranch, Discodoris. Further, the ophiuroid,
Amphiura trisacantha is apparently rare elsewhere
(Baker & Devaney 1981). Recent discoveries of
other rare fauna of essentially tropical affinity
include the first Australian records of Pisione and
Hesionura polychaetes in Spencer Gulf (HartmannSchroeder and Parker 1990a and b).
Northern Spencer Gulf also supports the most
extensive seagrass meadows in South Australia
(Edyvane 1995).
Approximately 4140 km2 of
seagrass have been recorded in northern Spencer
Gulf (north of Point Reilly), which represent 75% of
the total area of seagrass recorded in South Australia,
and 43% of the total area of seagrass recorded in
South Australia. These seagrass meadows flourish in
the shallow waters of the gulf (often less than 10m
deep in the northern part of the gulf), and provide the
basis for significant fish and shellfish production,
including the bulk of the state’s snapper, western
king prawn and blue crab catches. Growth of
Posidonia species is particularly vigorous, with high
leaf blade production and turnover rates (West &
Larkum 1979). Shepherd (1983) estimates an annual
leaf blade productivity in excess of 9 kg/m2 in
shallow water.
It is clear that habitats in the sheltered northern part
of Spencer Gulf are quite dissimilar in species
composition to those in the south. Northern areas
comprise mainly sandy and muddy substrates,
dominated by the seagrasses Posidonia sinuosa and
P.angustifolia,
Amphibolis
antarctica
and
Heterozostera
tasmanica;
and
benthic
invertebrates, such as razor fish (Pinna bicolor),
hammer oysters, sponges and ascidians. Very few
large brown algal dominated reefs occur in this
northern area.
Central and Southern Spencer Gulf
In contrast to northern Spencer Gulf, very few
systematic subtidal studies have been conducted in
the central and southern Spencer Gulf region, apart
from a recent survey by SARDI (Edyvane & Baker
1996). However, abalone stock assessment studies
carried out by the former SA Department of Fisheries
(Branden & Shepherd 1982a, b) provide some habitat
notes on the substrate, common algae and principle
grazing invertebrates for sites in south western
Spencer Gulf, from Port Lincoln to Franklin Harbour,
including Thorny Passage.
The mixed sand and rock substrates of the central
gulf are mainly covered with mixed Sargassum
species
(such
as
S.
linearifolium,
S.
heteromorphum, S. lacerifolium), and mixed
Cystophora species (such as Cystophora expansa,
C. brownii, C. monilifera and C. grevillei), with
Lobophora variegata as a dominant understorey
covering species.
In contrast to northern Spencer Gulf, the reef s in
the wave exposed southern and south-eastern areas
of Spencer Gulf, such as the foot of Yorke
Peninsula, are dominated by a variety of large brown
macroalgae, such as Carpoglossum confluens,
Seirococcus axilaris, Acrocarpia paniculata, and
mixed Sargassum and Cystophora species, as well as
an abundant and diverse understorey of green
algae; and diverse red algal assemblages comprising,
coralline, filamentous, succulent and membranous
red algal species. On a bioregional scale, southern
Spencer Gulf and the Gambier Isles south of the gulf,
are particularly diverse in their floral species
composition. A total of 52 red algal species
(including 6 species of coralline algae) occur as
dominants forming part of the benthic cover at sites
in south western Yorke Peninsula, at the base of
Spencer Gulf - this diversity of Rhodophyta is
greater than that recorded from most other survey
locations, apart from macroalgal-rich sites in the
south east of South Australia. Similarly, diversity
of Sargassum species is high on reefs in southern
Spencer Gulf.
The south-eastern part of Spencer Gulf, including
the coastal reef and islands around the base of Eyre
Peninsula (excluding the Sir Joseph Banks Group)
is particularly rich in brown and green macroalgae,
with a total of 33 and 11 species respectively
forming the benthic cover of sampled locations.
This diversity of brown and green algae occurring
as dominants in southern Eyre Peninsula region, is
comparable with that recorded for the south east of
South Australia, one of the most phycologically
diverse areas of South Australia. Clearly, the
southern Eyre Peninsula and the southern Yorke
Peninsula have close floral affinities, with a similar
number of dominant taxa (95 and 94 respectively)
and more than 60% of the percentage cover species
in common, including almost all of the dominant
Cystophora and Sargassum species found in both
regions.
A detailed account of the subtidal marine ecology of
Spencer Gulf has recently been prepared by Edyvane
& Baker (1996).
5.4
Seagrass Ecology
Seagrass beds are well developed in Spencer Gulf
colonising sandy-muddy areas of tidal flats, and
extending several metres deep. Heterozostera
tasmanica forms dense and pure masses in thick,
firm mud from low tide level down for 3-4 m, with
occasional plants as deep as 20 m. Posidonia
(tapeweed) extends large distances from about
0.5m below low tide to 20m or so deep. The
Posidonia leaves often carry a wealth of epiphytes
but only few macroalgae (for eg. Caulerpa
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SPENCER GULF REGION
cactoides, C.remotifolia) occur in or adjacent to the
beds.
Posidonia australis, the most widespread species,
grows sympatrically with P.sinuosa and
P.angustifolia in the shallower part of their range.
P.sinuosa is widely distributed to a depth of 15m in
sheltered bays and inlets, either in pure stands or
growing sympatrically with P.australis or
P.angustifolia. In more exposed areas it may form
meadows with Amphibolis spp. P.angustifolia
grows subtidally from 2-35 m deep. It frequently
grows in deeper water than P.australis. In it's
deeper range it is often found in association with
Heterozostera tasmanica or Halophila australis
and in sheltered positions in it's shallower range in
association
with
Amphibolis
antarctica.
Amphibolis antarctica grows in moderate to fairly
strong water movement, from the uppermost
sublittoral zone to 23m. Is an earlier coloniser in
denuded areas in Posidonia australis meadows,
where rhizomes still remain.
Other seagrasses of note in Spencer Gulf include:
Halophila australis which grows on sand and mud,
from low tide level to 23m deep; Ruppi spp.
(R.megacarpa, R.tuberosa); Lepilaena marina
which forms extensive low turfs in mid and lower
eulittoral zones on sandy mud tidal flats, often
growing in association with Ruppia tuberosa and
Zostera mucronata; and Amphibolis griffithii which
forms pure stands or mixed communities with
A.antarctica from low tide to depth of 5m.
A.griffithii generally extends into rougher localities
and tolerates lower light intensities than
A.antarctica.
Sedimentologically, the seagrass meadow of the gulf
(particularly in the northern reaches) act as a major
subtidal carbonate "factory", with high rates of in-situ
carbonate production and post-mortem skeletal
accumulation (Davies 1970, Patriquin 1972, Gostin
et al. 1984). Also trapped are terrigenous and aeolian
detrital grains, as well as both terrigenous and
calcareous muds. The Corallinaceae are important
carbonate producers, particularly Lithothamnium,
Jania and Corallina species. Benthic and epiphytic
foraminifers are also important contributors to the
sediment. Other sessile and vagile epifauna which
contribute to bed sediment are encrusting bryozoa,
gastropods, hydroids, echinoderms and ascidians.
5.5
Fish
While a full description of fish species in Spencer
Gulf is not available, the fish species of Eyre
Peninsula is relatively well documented (see
Glover & Olsen 1985).
The marine fish fauna found in the waters
surrounding Eyre Peninsula is typical of the
Flindersian Province of southern Australian coastal
waters (Glover & Olsen 1985). As such, many of
the species recorded in South Australian waters,
have also been recorded in southern and southwestern Western Australian waters, and to a lesser
extent, in the waters of western Victoria and northwest Tasmania. There are some 300 species of
known marine fish recorded off Eyre Peninsula
down to the base of the continental slope, which
represents approximately 67% of the species
recorded from all South Australian marine waters
(Glover 1982).
Most of the species along the Eyre coast tend to be
inshore with fairly permanent resident populations.
However, there are some regular migratory visitors
such as the Australian Salmon and occasional
oceanic vagrants such as oceanic Sunfish (Mola
sp.), Basking Shark (Cetorhinus maximus), Black
Marlin (Makaira indica), and the Lizardfish
(Saurida undosquamis). Their presence in these
waters can be attributed to the easterly flowing
Leeuwin Current (Glover & Olsen 1985).
Many sea-connected waterways occur along the
east coast of Eyre Peninsula. Marine and primarily
marine species, such as the Congolli (Pseudaphritis
urvillii), may enter and frequent the estuaries and
lower reaches of these and other coastal waterways.
Among the native freshwater species, which spend
part of their life cycle at sea - the Common
Galaxias (Galaxias maculatus) and the Black
Bream (Acanthopagrus butcheri), have been
recorded in the Tod River. The Common Galaxias
has also been recorded in the North Shield Creek,
Lake Wangary and a tributary of Little Swamp.
Small-Mouthed
Hardyhead
(Atherinasoma
microstoma) have been recorded in the permanent
spring-fed saline waters of Lakes Hamilton and
Newland, on the west coast south of Venus Bay,
while eleven normally marine species of fish have
been recorded in Lake Wangary, which has a
connection with the sea via Minniribbie Creek.
The waters of Spencer Gulf are among some of the
most commercially productive in South Australia.
The most valuable single species fishery in Spencer
Gulf is the Western King Prawn (Penaeus
latisulcatus), which accounted for 80.87% of the
State's total catch in 1996/97.
The marine recreational fishery is renowned for the
variety of species which provide abundant and
excellent sport for line, spear and big-game fishers.
Page 85
SPENCER GULF REGION
5.6
Marine Mammals
The offshore islands in southern Spencer Gulf,
represent important breeding sites for both, the
Australian Sea Lion (Neophoca cinerea) and the
New Zealand Fur Seal (Arctocephalus forsteri) in
South Australia. Important breeding sites for
Australian Sea Lions in this region occur at
Dangerous Reef and to a lesser extent, English
Island (Sir Joseph Banks Groups), while the
Neptune Islands has the largest breeding colonies
of New Zealand Fur Seals in South Australia,
comprising approximately 51% of the total
Australian population.
Other islands off the
southern Eyre Peninsula have smaller but
nevertheless important colonies of Sea Lions and
Fur Seals, and breeding also takes place at some of
these sites (Watt & Ling 1985).
Some 18 species of whales have been recorded in
South Australian coastal waters (Aitken 1971).
Pilot Whales (Globicephala melaena) enter Gulf St
Vincent occasionally and have gone aground on
local beaches. The largest recorded mass stranding
of whales occurred in 1944 when almost 300 False
Killer Whales (Pseudorca crassidens) went
aground at Port Prime in Gulf St Vincent (Glover
& Ling 1976).
Both, the Bottlenose Dolphin (Tursiops truncatus)
and the Common Dolphin (Delphinus delphis) are
common in Spencer Gulf.
5.7
Seabirds
The islands of Spencer Gulf are also home to
breeding populations of several species of seabirds
protected under the South Australian National
Parks and Wildlife Act. These include the Little
Penguin, White-faced Storm Petrel, Black-faced
Cormorant, Pied Cormorant, Crested Tern, Caspian
Tern, Silver Gull, Pacific Gull. Little Penguins
breed on Pondalowie Islands (Royston and Middle
Islands), Wardang Group (Goose and Green
Islands), Wedge Island, Sir Joseph Banks Group
(Kirkeby, English, Duffield, Hareby, Roxby,
Blythe, Reevesby, Lusby, Partney, and Winceby
Islands), and Round Island (Lipson Cove) (Copley
1996). White-faced Storm Petrels have been
recorded breeding on Wedge Island and the Sir
Joseph Banks Group of islands (ie. Kirkby, Sibsey,
Hareby, Langton, Blythe, Dalby, Reevesby, Lusby,
Partney, Winceby Islands and almost certainly,
Spilsby Island) (Copely 1996).
Black-faced Cormorants breed on the Wardang
Group (Rocky Islet, White Rocks), Sir Joseph
Banks Group (Winceby, Sibsey, English Islands),
Dangerous Reef, and Lipson Island (Copley 1996).
Pied Cormorants breed on Little Goose Island, Bird
Islands Conservation Park, Shag Island (Port
Broughton), Fishermans Creek, mangrove creeks of
Port Pirie, Weerona Island, Chinaman's Creek,
Winceby Island, Franklin Harbour. Silver Gull
breeding locations include Pondalowie Islands,
Wardang Group (Daly Head Island), Bird Islands,
Sir Joseph Banks Group (Marum, Blythe, Duffield,
Stickney, Sibsey), Dangerous Reef, Lipson Cove,
Tumby Island, Round Island and Cape Donington.
Pacific Gull breeding populations have been
recorded on Little Goose Island, Bird Island and
the Sir Joseph Banks Group (Marum, Reevesby,
Langton, Roxby, Duffield, Stickney, Sibsey,
English, Kirkeby) and Dangerous Reef.
A rare visitor to South Australian waters, the Redtailed Tropic-Birds has also been recorded breeding
on South Neptune Island (Copley 1996). Species
listed as `vulnerable' under the South Australian
National Parks and Wildlife Act, such as the Little
Tern and Fairy Tern also breed on the offshore
islands and coastal regions of Spencer Gulf. The
Little Tern has been recorded at Ward Spit (Point
Germein). Recent studies indicate that the Little
Tern may realistically be regarded as endangered
within South Australia (Copley 1996). Breeding
populations of Fairy Terns have been recorded at
Lipson Cove, Sir Joseph Banks Group (Kirkby,
Langton and Stickney Islands), South Neptune
Island and the Islet of North Neptunes.
Crested Terns have been recorded breeding on the
Wardang Group (Goose, Daly Head and Rocky
Islands, Seal Rocks), Bird Islands, Ward Spit, Sir
Joseph Banks Group (Kirkby, Winceby, Lipson
Island), and the Neptune Islands (Lighthouse
Island, South Neptune). Caspian Terns breed on
Wardang Island, Bird Island, Ward Spit, Franklin
Harbour (Entrance Island), Sir Joseph Banks Group
(Kirkby, Blythe, Lusby, Roxby, Partney Islands)
and the South Neptune Islands (Copley 1996).
Page 86
SPENCER GULF REGION
MARINE CONSERVATION VALUES
1
SIGNIFICANT
BIOLOGICAL
PHYSICAL FEATURES
AND
coastal erosion (Scoffin 1971). Seagrass meadows
also support a prolific skeletal biota as infauna and
epiphytes, which in turn, provides the carbonate
basis for sediments in the region.
Mangroves
1.1 Biological
Relic Tropical Fauna and Flora of Northern
Spencer Gulf
The benthic flora and fauna of Northern Spencer
Gulf is characterised by a significant and very
distinctive, relict tropical element (Shepherd 1983)
and is nationally recognised as a distinct
biogeographical region, known as the `Northern
Spencer Gulf Bioregion' (IMCRA 1997). Although
most of the algal species recorded in Northern
Spencer Gulf have intermediate warm to cool
temperate affinities (occurring throughout the
southern Australian region), some algal species,
such as Sargassum decurrens and Hormophysa
triquetra, are nowadays only distributed in tropical
and subtropical regions. Northern Spencer Gulf
appears to be impoverished in terms of overall
species richness, but relatively rich in species
which are either endemic or have tropical affinities
Extensive Seagrass Meadows
Spencer Gulf, particularly the northern reaches,
support the most extensive seagrass meadows in
South Australia, some of the largest in Australia
(Edyvane 1996).
These extensive seagrass
meadows flourish in the shallow waters of the gulf,
generally in waters less than 15m, and provide the
basis for the significant productivity of the gulf in
terms of fisheries and prawn production.
Seagrasses cover a total area of approximately
5,512 km2 in Spencer Gulf, of which 4,138 km2 is
located in northern Spencer Gulf (ie. north of Point
Riley). Together, the seagrasses of Spencer Gulf
represent 57% of the total area of seagrasses
recorded in South Australia (ie. 9,612 km2).
Most of the seagrasses in the gulf are located in the
central northern reaches of the gulf (ie. Yonga
Biounit, 248,596 ha), in the Tiparra Reef region (ie.
Tiparra Biounit, 83,912 ha) and the Port Lincoln
region (ie. Jussieu Biounit, 56,956 ha).
Seagrass meadows are particularly important for a
number of reasons: as primary producers they
occupy the base of the food chain; they provide
important or “critical” habitats such as nursery,
breeding or feeding areas for the juveniles and
adults of many fish, crustaceans and other marine
animals, including a large number of commercial
species (Bell & Pollard 1989, Howard et al. 1989);
and their extensive root and rhizome systems
stabilise nearshore sediments and sand banks,
enhancing coastal water clarity and reducing
The Spencer Gulf region contains the most
extensive areas of mangrove forests and tidal
wetlands in South Australia (and the largest areas
of temperate mangroves in Australia) (Edyvane
1996). Associated with the mangrove habitats are
the biologically rich mud flats, coastal saltmarshes
and seagrasses. Together, mangrove and saltmarsh
communities along the South Australian coast total
approximately 82,000 ha, with the largest
communities occurring in Spencer Gulf (46,000 ha)
and Gulf St Vincent (20,000 ha). Other substantial
communities occur in lower Spencer Gulf (6,000
ha), on the west coast of Eyre Peninsula (9,000 ha)
and on Kangaroo Island (7,000 ha) (DELM 1993).
In Spencer Gulf, mangrove forests occur north of
Point Lowly, from Port Pirie to Port Broughton, in
Franklin Harbour, and to a lesser degree near
Tumby Bay.
Mangrove forests comprise a single species, the
Grey Mangrove, Avicennia marina, which forms a
low woodland forest extending from mean sea level
to spring high-tide level. Progressively higher
vegetated zones are a Halosarcia-Sarcocornia
(saltmarsh) association, a Sclerostegia-Halosarcia
(saltmarsh) association and an Atriplex (saltbush)
association (Chinnock 1980). These tidal wetlands
are areas of considerable productivity and represent
significant feeding habitats for waterfowl and
waders, and also represent key nursery, feeding and
breeding areas for many economically important
species of fish and crustaceans (eg. Western King
Prawn, King George Whiting, Southern Sea
Garfish).
Conspicuous algal mats, which form as a result of
sediment trapping by filamentous blue-green algae
are associated with both, the mangrove and
saltmarsh flora. A variety of marine organisms,
mostly gastropods, bivalves, polychaetes and
crustaceans, also live in and on the mangrove mud,
and are a key food source.
Productivity
The extensive mangrove and seagrass areas of
Spencer Gulf, particularly Northern Spencer Gulf,
are also areas of very high fisheries production for
several commercial fish and crustacean species. In
terms of overall fisheries production, the northern
reaches of Spencer Gulf (south of Point Lowly)
supports the largest Western King Prawn (Penaeus
latisulcatus) fishery in the Australia. Some 1500
tonnes of prawns, valued at $20 million, are caught
annually in the region, which represents
Page 87
SPENCER GULF REGION
approximately 75% of the State's total prawn
harvest. Northern Spencer Gulf itself provides
approximately 45% of the State's marine scalefish
catch and more than 45% of the State's blue crab
catch, although the bulk of the these catches occurs
between Moonta and Ward Spit.
The mangrove and seagrass areas of Spencer Gulf,
particularly Northern Spencer Gulf, also constitute
important nursery areas for several commercial fish
and crustacean species caught both locally and in
the southern areas of Spencer Gulf. The upper
regions of Spencer Gulf are important as spawning
or nursery areas for the Western King Prawn as
well as for numerous species of scale fish of
commercial interest. The size of the estuary and its
extent and diversity of its associated wetlands
suggest that its contribution to the ecology of
Spencer Gulf would be significant (Bucher &
Saenger 1989).
Coastal Wetlands of National Importance
A Directory of Important Wetlands in Australia
(ANCA 1996) list the following coastal wetlands of
national importance in Spencer Gulf:
−
−
−
−
Tod River Wetland System
Tumby Bay
Franklin Harbor
Upper Spencer Gulf Mangrove System
Shorebirds
The Spencer Gulf region has been identified as an
area of international importance for shorebirds by
Watkins (1993).
Australian Sea Lions (Neophoca cinerea) and
the New Zealand Fur Seal (Arctocephalus
forsteri)
The offshore islands in this region represent
significant breeding sites for the rare Australian
Sea Lions (Neophoca cinerea) and the New
Zealand Fur Seal (Arctocephalus forsteri) in South
Australia.
Breeding colonies of the rare Australian Sea Lion
have been recorded on Dangerous Reef (East Rock
and West Reef), Albatross, English, and North
Islands and Peaked Rocks, while breeding possibly
occurs on Neptune (East), Price, Lewis, Smith
Rock and Buffalo Reef (Gales 1990, Gales et al.
1994). Haul out and basking sites also occur on
Williams, Thistle, Hopkins, Smith, Little, Langton,
Low Rocks, Neptune (West), Neptune (North),
Neptune (South), and South West Rock (Watts &
Ling 1985, Gales 1990). Of particular significance
is Dangerous Reef which supports the third largest
breeding population of sea lions in the world
(SANPWS 1990, Gales 1990, Gales et al. 1994).
The largest breeding colonies of fur seals in South
Australia and Australia occurs on the Neptune
Islands (see Eyre Province).
Smaller but
nevertheless important breeding colonies however
have been recorded on Liguanea, Little Hummock,
Four Hummocks, Rocky (South) and Greenly
Islands (Shaughnessy 1990). Haul out and basking
sites include Cape Rock, Rocky (North) Islands,
Curta Rocks, Williams Island, Low Rocks and
Albatross Island (Shaughnessy 1990, Shaughnessy
et al. 1994).
Sir Joseph Banks Group
The Sir Joseph Banks group of islands represent a
relatively pristine environment and has unique
molluscs, important bird colonies and breeding
colonies of the Australian Sea Lion. The islands
are particularly significant as the most important
breeding area for Cape Barren Geese in South
Australia.
Dangerous Reef
Dangerous Reef is one of the three major sites for
breeding of the rare Australian Sea Lions in South
Australia (along with the Pages and Seal Bay,
Kangaroo Island). Sea lions numbers on East,
Main and West Reefs vary from a total of 530
recorded in 1982 (Watts & Ling 1985) to 424 sea
lions in 1990 (Gales 1990). As such, this area
represents the third largest breeding colony in
South Australia (after the colonies on the North and
South Pages), with an estimated 236 pups produced
in 1990 (Gales 1990).
Dangerous Reef is also significant as a major
research and filming site for the White Shark
(Carcharodon carcharias).
Tiparra Reef
Tiparra Reef is an extensive seagrass-reef shoal
system in Moonta Bay, that extends along the
western coastline of Yorke Peninsula, from Cape
Elizabeth to Warbuto Point and Bird Islands. Like
the seagrass-reef shoal system of Orontes Shelf in
Gulf St Vincent, the calcreted Pleistocene shell bed
forms extensive flat rocky surfaces, or low
erosional escarpments and provides excellent
habitat for a diversity of marine life, including
sponges, ascidians, and reef molluscs, and is also
an outstanding mixed fishing ground.
The
diversity and productivity of the area, particularly
on the reefs, is enhanced by the tidal currents of the
northern gulf. Tiparra Reef is presently the major
commercial fishing ground for Greenlip Abalone
(Haliotis laevigata) in South Australia, with
catches in the area representing approximately 25Page 88
SPENCER GULF REGION
30% of the total South Australian catch for this
species (or 65-80% of the total catch for the Central
Zone). A conservation reserve was proposed for
the reefs at Cape Elizabeth by the former SA
Department of Fisheries in 1980.
Offshore Islands
All the offshore islands in Spencer Gulf
(particularly southern Spencer Gulf) could be
considered as biologically significant as they
support a rich diversity of flora and fauna,
particularly birds and Australian Sea Lions.
Other Recognised
Significance
Areas
of
Biological
In early 1974, the former Department of Fisheries
advised the Yorke Coast Protection District Board
of six significant areas which were under
consideration for declaration as Aquatic Reserves.
Areas in the Spencer Gulf region included:
(i) Gleesons Landing to Daly Head (for education
purposes)
(ii) The islands and surrounding waters of
Althorpe and neighbouring islands (as a
conservation reserve to protect the Blue
Groper population)
(iii) The reefs at Cape Elizabeth (for conservation
purposes)
None of these areas has since been declared as
Aquatic Reserves. However, Gleesons Landing is
now a recognised sanctuary for Southern Rock
Lobster.
1.2
Physical
Northern Spencer Gulf
All of the northern Spencer Gulf can be considered
as physically significant owing primarily to its
nature as inverse estuary which contributes to the
physical properties of the region. The area is also
recognised at a global level as a being one of the
most significant areas of temperate carbonate
production in the world.
"Geological Monuments"
There are 14 areas of geological significance in
Spencer Gulf which are associated with the
coastline or offshore waters. These areas have
been identified and recognised as "geological
monuments" by the South Australian Museum and
the Geological Society of Australia and include the
following sites:
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
Memory Cove
Kirton Point (Port Lincoln)
Cape Donington
Arno Bay
"Glensea" (10 km north of Shoalwater Point)
Port Hughes - Port Moonta
Wardang Island
Wardang Island, Cliff Point
Port Victoria
Point Turton
Corny Point
Browns Beach
Meteor Bay
Giles Point
Further details of these areas are supplied in the
relevant regional biounit descriptions below.
2 SIGNIFICANT CULTURAL AND
HISTORICAL FEATURES
The following description of Aboriginal and
european history in the Gulfs province is
necessarily brief and selective. The aim is to give
the province a historical perspective with emphasis
on coastal and maritime history. Only details of
Aboriginal historical and cultural sites that have
been published in the available literature are
described. Aboriginal sites, objects and remains
are protected under the South Australian
Aboriginal Heritage Act (1988), and a register of
such sites, objects and remains is kept with the
Aboriginal Heritage Branch of the South Australian
Department of Environment and Planning.
2.1
Aboriginal
According to Tindale (1974), the Nauo people
probably occupied the southern Eyre Peninsula
from Venus Bay, south to Port Lincoln and west to
Franklin Harbour.
It has been suggested
(Schurmann 1879) that the Nauo in the south were
closely linked linguistically to the Banggala people.
Banggala pressures had caused the Nauo to
contract to the southwest - on the northeastern side
of the Peninsula, the Banggala were being forced
southward to take over Nauo land.
Page 89
SPENCER GULF REGION
However, the Nauo land of the dead was on islands
in Spencer Gulf, while the Banggala located theirs
on islands to the west, probably out from Coffin
Bay (Angus 1847), implying considerable
movement and displacement of local groups must
have taken place prior to European contact. It is
not known whether the Nauo originally occupied
the western area of the peninsula or were forced in
that direction by the Banggala.
The Yorke Peninsula coast was, in the past,
intensively occupied by Aboriginals of the
Narungga tribe and important evidence of this
occupation is to be found at many places. Most
evidence of Aboriginal occupation is to be found in
the sand dunes along the west coast of the
Peninsula. Amongst the most important areas are
in the Cape Elizabeth/Tiparra Springs dunes and in
the dunes north of Moonta Bay. Other west coast
areas where evidence is know to exist are in the
dunes between Port Hughes and Cape Elizabeth
and in those south of Port Victoria. Other known
areas are at Point Yorke on the South Coast and at
Black Point and Tiddy Widdy on the east coast.
The latter two areas are of considerable
importance, though the Tiddy Widdy dunes have
been looted.
2.2
European
Early Discoverers
The first explorer to touch the South Australian
coast was the Dutchman, Francors Thyssen in the
`Gulden Zeepard' in 1627. He sailed eastwards
across the Bight as far as the Nuyts group of
islands, but turned back because of the inhospitable
coast. It was more than 150 years later when the
Frenchman D'Entrecasteaux sailed eastwards to the
Nuyts Archipelago and then to Van Diemen's Land.
The exploration and mapping of the coast of Eyre
Peninsula began with the Englishman Flinders and
his crew who arrived aboard the `Investigator' at
Fowlers Bay on 28 January 1802.
He proceeded in an easterly direction charting the
outline of the Peninsula and naming features after
places in his native Lincolnshire, after supporters
of the voyage, and from the way the features
appeared to him (eg. Smoky Bay). He also named
islands after his crew, such as at Cape Catastrophe
where the Master of the `Investigator' (Thistle), and
seven crewmen were drowned. Memory Cove was
so named to commemorate those lost.
Following the initial discoverers came whalers and
sealers, and before settlement had begun, there was
a thriving whaling, sealing and fishing industry.
The remains of early sealers' huts and whaling
stations may still be seen on some of the beaches
and offshore islands.
The South Australian
Company, in addition to its operations at Encounter
Bay on Fleurieu Peninsula, established whaling
stations on Thistle Island at the foot of Spencer
Gulf and at Sleaford Bay on the tip of Eyre
Peninsula.
Port Lincoln was founded in March of 1839, and
increased settlement and agriculture began on a
broader scale in the region. Gulf St Vincent was
discovered in March 1802 after Flinders discovered
the Yorke Peninsula when he sailed down the
western side of it after turning back from the head
of Spencer Gulf.
Flinders named Spencer Gulf after Earl Spencer,
Yorke Peninsula after Charles Philip Yorke, and
Gulf St Vincent after Earl St Vincent. All three
men were at some stage acting as the First Lord of
the Admiralty.
Following Flinders, sealers, whalers and land
speculators soon settled the coastal areas of the
Gulfs.
Coastal Ports
The chief method of communication between
Adelaide and the coastal settlements was by sea.
Port Clinton, established in 1863 to supply the
mining towns of Moonta and Kadina, was the first
of the ports on the Gulf St Vincent coast of Yorke
Peninsula. At the minor Gulf St Vincent ports of
Port Price, Port Julia, Pine Point, Wool Bay and
Coobowie, townships grew up at the landward ends
of the jetties constructed for the ketch trade, which
dwindled away until the last of the old time vessels
ceased crossing the Gulf in the mid 1960s. These
jetties are now important reminders of that time
and those that remain are now used by tourists,
divers and fishers.
Port Victoria, in the lee of Wardang Island, became
one of the last windjammer ports in the world. It
was still being used by sailing ships to load grain
right up until the Second World War.
Shipwrecks
There are a number of shipwrecks located within
the Spencer Gulf region. Within the waters of
Spencer Gulf, designated wrecks are protected by
the (South Australian) Historic Shipwrecks Act
1981. Ten shipwrecks in the gulf have been
protected via declarations under this Act.
In
contrast, wrecks in the waters around Neptune and
Gambier
Islands
are
protected
under
Commonwealth legislation, under the Historic
Shipwrecks Act 1976. Under this Act, all wrecks
older than 75 years old are granted automatic
protection under the Commonwealth legislation,
whether designated or not.
Page 90
SPENCER GULF REGION
Along the Yorke Peninsula coast, nearly a hundred
shipping accidents have been recorded from cutters
to clippers and steamers. The number of deaths in
the accidents has been relatively small. Half of
these incidents occurred on the south coast of
Yorke Peninsula, from Cape Spencer to Troubridge
Shoal. Another three dozen occurred on the west
coast from Reef Head to Cape Elizabeth and half of
these occurred near Wardang Island and in the
harbour of Port Victoria.
Port Victoria and Wardang Island are significant
for both European heritage with its numerous
shipwrecks, and for Aboriginal heritage. It is also
important for the contemporary Aboriginal
population living in the area as Wardang is owned
by the Aboriginal Lands Trust and is leased to the
Point Pearce Community Council.
Heritage Sites
Several European heritage sites in Spencer Gulf are
formally listed on State Heritage Register:
−
−
−
−
3
Port Germein jetty.
Former Point Pearce Aboriginal mission.
Lighthouse complex and other structures on
South Neptune Island.
Lighthouse at Corny Point (also listed on the
National Heritage Register).
Marine Sanctuaries
−
Gleesons Landing (350 ha)
−
Marine Parks
None
−
−
−
−
−
−
−
−
−
−
−
−
−
Netting Closures
Port Lincoln (Proper, Boston, Louth, Peake
Bays)
Tod River
Tumby Bay
Port Neill
Arno Bay
Franklin Harbour
Northern Spencer Gulf (Douglas Bank)
Germein Bay
Fisherman Bay
Port Victoria
Brown's Beach
Pondalowie Bay
Wedge Island
CURRENT CONSERVATION STATUS
OF SPENCER GULF
Spencer Gulf is one of most well represented in
terms of Marine Protected Areas of all the coastal
regions in South Australia. As such, 4 of the 13
Aquatic Reserves which have been declared in
South Australia, occur in this region. No large,
multiple use Marine Parks have been declared in
this region. As with other coastal regions in South
Australia, the majority of MPAs in Spencer Gulf
comprise `netting closures', many of which have
generally not been formally recognised as MPAs
(see Ivanovici 1985, McNeill 1991). Only one
Marine Sanctuary has been declared along this
coast (ie. Gleeson’s Landing).
This was
established for the protection of the Southern Rock
Lobster.
−
−
−
−
Marine Reserves
Whyalla-Cowleds Landing (3,230 ha)
Blanche Harbour-Douglas Bank (3,160 ha)
Yatala Harbour (1,426 ha)
Goose Island (54 ha)
Page 91
SPENCER GULF REGION – JUSSIEU BIOUNIT
X
MARINE BIOGEOGRAPHY AND CONSERVATION VALUES OF THE
JUSSIEU BIOUNIT
This biounit extends from Cape Catastrophe on the Eyre Peninsula, north to Salt Creek (Tumby Bay), and
covers an area of 240,439ha and a coastal distance of approximately 191 km (including Boston Island, but
excluding other offshore islands).
The biounit includes the offshore islands of Thorny Passage (Thistle, Albatross, Hopkins, Smith, Lewis, Little,
Grindal, Taylor, Owen), Port Lincoln (Bickers, Boston, Donington, Grantham, Louth, Rabbit), Dangerous Reef,
the Sir Joseph Banks Group, Spilsby Island and Tumby Island. 16
(16 Although this biounit is included in the Eyre Coast Protection District by Coast Protection Board, it has not
been included in this region in this report. This is primarily because the oceanography of this region is more
aligned with that of the Spencer Gulf than the west coast of Eyre Peninsual.)
MARINE BIOGEOGRAPHY
1
OCEANOGRAPHY
This biounit forms the southwestern arm of
Spencer Gulf and has an overall easterly
orientation. Consequently, it is a zone of low wave
energy with prevailing offshore winds.
2
GEOLOGY
AND
GEOMORPHOLOGY17
COASTAL
In summary, the coast of this biounit consists of
highly variable morphology controlled generally by
the bedrock geology.
There is some minor
Holocene barrier and sandflat sedimentation along
the more exposed sections and embayments, whilst
in other areas cliffs and shore platforms form the
shoreline. Five large bays (Boston, Proper, Porter,
Louth, Peake) and two peninsulas (Bolingbroke,
Jussieu) help create a highly crenulate and variable
coast.
The first coastal region is the East Jussieu
Peninsula shoreline which runs north-south for 34
km from Cape Catastrophe to Cape Donington.
The shoreline is dominated by the bedrock
geology, with predominantly cliffs and shore
platforms. Low energy carbonate rich beaches,
backed by stable foredunes and rock embankments
and fronted by 100-200 m wide sandflats, occur in
slight embayments, particularly north of Shag
Cove. At Memory Cove a fine grained reflective
beach is backed by a single stable foredune
underlain by a shingle ridge.
17
The region from Cape Donington to Point Boston
is highly crenulate and dominated by Boston Bay
and Proper Bay. Proper Bay is a large bedrock
controlled embayment with 53 km of shoreline
from Cape Donington to Kirton Point and facing
northeast. Northerly generated wind waves have
induced sparse Holocene sedimentation around the
bay shoreline and marginal erosion of the coarse
outwash deposits has produced rocky strandflats.
Both Tulka Well and Spalding cove act as sinks for
the generally southerly longshore drift along the
bay shores. Along the southern shore, low energy
sandflats front relatively stable beaches which are
backed by low stable foredunes. North of Proper
Bay is Porter Bay which is fronted by several
hundred metres of intertidal sandflats with minimal
beach activity.
The Boston Bay shoreline extends 22 km
(including Boston Island) and its very low wave
energy conditions in the southern portion has
permitted the development of Port Lincoln. In the
higher energy northern end of the bay, occasional
swell and wind waves have built a series of shingle
ridges, capped by a foredune ridge barrier. There is
a Holocene barrier backed by a low Pleistocene
barrier which is significant as it is apparently the
first Pleistocene barrier deposit south of Whyalla.
At North Shields the narrow foredune ridge barrier
gives way to a low energy, low cliffed coast.
These cliffs composed of unconsolidated outwash
material, are actively eroding with up to 10 m of
cliff being eroded during the past 30 years. It is
likely that a higher energy window exists between
Point Boston and Point Maria on Boston Island
which concentrates wave energy on North Shields
during high wave events.
From Eyre Peninsula Coast Protection District Study Report.
Page 92
SPENCER GULF REGION – JUSSIEU BIOUNIT
Louth Bay is a carbonate rich bay with beach and
dune sediments approaching 100% carbonate. The
northern portions are more exposed to occasional
ocean swell and southerly winds, whilst in the
southern region occasional beach ridges are fronted
by wide sandflats. Louth Island is scarped with
seacliffs and shore platforms on the south side, and
a 1km long sand spit extends off the northern side.
are common on the north-western portion of
some islands. Winceby and Reevesby Islands
are particularly noted for the presence of
abundant
amphibolite,
a
dark-green
metamorphic rock, rich in iron and magnesium
silicate minerals.
−
Thistle Island (Thorny Passage): crystalline
basement overlain by calcareous aeolianite.
Steep cliffs of calcareous aeolianite rise
directly above sea level. On the leeward
(eastern) side, recent beach sands have been
deposited. Several small lakes exist separated
from the sea by a narrow strip of coastal dunes.
−
Albatross Island, Hopkins Island, Smith Island
and Grindal Island: predominantly crystalline
basement with a thin layer of calcareous
aeolianite.
−
Lewis Island and Little Island: both aeolianite
on crystalline basement.
2
Peake Bay (10 km ) contains small stable barriers
that increase in width and elevation to the east and
are fronted by wider, deeper sandflats. Their
formation is likely to be caused by the increasing
exposure to wave and onshore wind energy.
The 22 km of coast from around Bolingbroke
Peninsula to Cape Eiler is dominated by the
Precambrian bedrock which forms the peninsula.
Low energy beaches fronted by seagrass covered
reefs and sandflats surround most of the coast. In
several small embayments reflective beaches are
backed by usually single stable foredune barriers
and minor backbarrier deposits. Point Bolingbroke
is joined to the mainland via a double sided
'tombolo like' barrier. The west-facing barrier is
exposed to wind generated waves from Louth Bay
and is consequently higher energy with wider,
deeper sandflats and minor dune transgression.
3
BIOLOGY
Major Inshore Habitats
The final region from Cape Eiler to Salt Creek is
dominated by Holocene barrier-backbarrier
deposits with a cuspate foreland in lee of Tumby
Bay. The 15 km long northern barrier consists of a
foreland focused on Salt Creek mouth comprising a
foredune ridge barrier backed by tidal flats. The
low energy southern section is the site of Tumby
Bay township which terminates at an inlet fronted
by an intertidal ebb tide delta which has been
dredged for marina access. South of Tumby,
extensive supratidal and intertidal flats (the latter
covered by mangrove) back onto two beach ridgeforedune ridge barriers which join as a cuspate
foreland.
−
Major intertidal habitats in the biounit include
bays and estuaries (ie. intertidal mudflats),
sand beaches and rocky shores.
−
Of the total inshore subtidal habitats mapped
in this biounit (153,526 ha), sandy bottoms
comprise 65,921 ha (42.9%), seagrass
meadows comprise 56,956 ha (37.1%) and
reefs comprise 30,649 ha (20.0%).
This biounit is characterised by numerous offshore
islands. The following are of geological interest:
−
−
The Sir Joseph Banks Group of islands lie
eastward of Louth Bay and include; Winceby,
Reevesby, Marum, Partney, Lusby, Kirkby,
Blyth, Hareby, Roxby, Langton, Boucaut,
Duffield, Stickney, English and Sibsey island.
These are low lying islands covered with a
marsh-saltbush shrubland. All islands consist
essentially of a basement of crystalline rock
(ie. granite), overlain by calcareous aeolianite
(ie. limestone) and capped, in part, by
consolidated dune limestone and recent
unconsolidated sand dunes. Many of the islands
have well developed beaches, while sand dunes
Major Benthic Communities
•
Macroalgal
There is a wide variety of reef communities in
this region, due to the wide range of wave
exposure and current conditions. Along the
exposed rocky granite shores, reefs and
islands in this region (eg. Hopkins Island,
Taylor Island), subtidal rocky shore
macroalgal communities are typically
dominated by the fucoids, Cystophora
monoliformis, C.siliquosa, and C.monolifera
and the red algae, Osmundaria and Haliptilon
occur in shallow waters (ie. <5m). In deeper
waters, rocky reef communities are dominated
by Ecklonia radiata, Seirococcus axillaris and
Acrocarpia paniculata with species of
Cystophora (C.platylobium, C.racemosa,
C.moniliformis) as sub-dominants, and also a
Page 93
SPENCER GULF REGION – JUSSIEU BIOUNIT
wide range of large understorey red algae (eg.
Osmundaria
prolifera,
Plocamium,
Phacelocarpus, Carpophyllis, Carpopeltis,
Peysonnelia, Sonderopelta) and green algae
(Caulerpa flexilis, C.obscura, C.brownii,
C.simpliuscula ).
−
−
•
−
Along moderate and sheltered coasts (eg.
Point Bolingbroke, Louth Island, Taylor
Island) rocky reefs are commonly dominated
by species of Cystophora
(C.expansa,
C.brownii, C.monilifera, C.moniliformis),
Scaberia agardhii, and species of Sargassum
(S.decipiens,
S.heteromorphum,
S.verruculosum) and understorey species of
Dictyotales (eg. Lobophora, Zonaria).
Within the Sir Joseph Banks Group, on
moderately exposed rocky coasts (ie. Stickney
Island), sutidal communities dominated by
Ecklonia radiata and mixed fucoids,
comprising
Sargassum
linearfolium,
S.paradoxum, S.spinuligerum, S.lacerifolium)
with species of Cystophora (C. siliquosa,
C.monoliformis, and C.monilifera) as subdominants. The understorey is dominated by
Osmundaria prolifera, encrusting and
articulated coralline algae (eg. Amphiroa) and
the prostrate brown alga, Lobophora
variegata. On sheltered coasts, rocky reefs
are commonly dominated by species of
Cystophora
(C.expansa,
C.brownii,
C.monilifera,
C.moniliformis),
Scaberia
agardhii, Caulocystis ulvifera, and species of
Sargassum (S.decipiens, S.heteromorphum,
S.verruculosum) and understorey species of
Dictyotales (eg. Lobophora, Zonaria) and
Botrycladia obovata. Reefs within the island
group, typically occur in shallow waters,
generally occurring down to 10-12m depth.
Seagrasses
There are extensive areas of seagrass within
this region, due to the large number of
sheltered sandy embayments (Proper, Lincoln,
Boston, Louth, Peake and Tumby bays).
These bays are commonly dominated by
Posidonia australis to shallow waters (down
to approximately 4m) and are dominated by
P.sinuosa and P.angustifolia in deeper waters.
Sparse meadows of Halophila australis occur
as deep as 23m in the offshore gulf waters.
−
Seagrass meadows occur throughout the Sir
Joseph Banks Group, generally in the lee of
islands and in deeper waters (>10m). Sandy
sediments dominated by Posidonia sinuosa,
P.angustifolia and Amphibolis antarctica in
shallow areas.
Coastal and Offshore Islands (or Reefs)
−
Thorny Passage (ie. Thistle, Smith, Hopkins,
Albatross, Lewis, Little, Grindal, Taylor, and
Owen Islands).
−
−
Bickers, Grantham Islands (Proper Bay).
Boston Island (Boston Bay).
−
Louth Island, Rabbit Island (Louth Bay).
−
Sir Joseph Banks Group of Islands (including
Blyth, Boucaut, Dalby, Dangerous Reef,
Duffield, English, Hareby, Kirkby, Langton,
Lusby, Marum, Partney, Reevesby, Roxby,
Seal Rock, Sibsey, Spilsby, Stickney, and
Winceby Islands, and Buffalo Reef, and
Buffalo and Smith Rocks).
−
Tumby Island.
Rivers/Estuaries
−
−
Tod River (Louth Bay).
First and Second Creek (Tumby Bay).
MARINE CONSERVATION VALUES
1
1.1
SIGNIFICANT
BIOLOGICAL
PHYSICAL FEATURES
AND
Biological
Coastal and Marine Wetlands of Recognised
National Importance
−
The Tod River Wetland System (Louth Bay)
has been identified as a wetland of national
importance (see ANCA 1996). The area
consists of a series of permanent rivers and
creeks that act as tributaries for the Tod River,
and a tidal estuary associated with wide mud
flats and sand flats where the Tod River meets
the sea. The Tod Estuary is significant as it is
one of the few, true estuarine environments on
the Eyre Peninsula (Lloyd and Balla 1986).
The rivers provide an important drought
refuge for waterbirds and breeding habitat for
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SPENCER GULF REGION – JUSSIEU BIOUNIT
other aquatic fauna, while the estuary is a
nursery area for a variety of fish species.
Some of its fish freshwater native species
spend at least part of their life cycle at sea: the
Common Galaxias (Galaxias maculatus) and
Black Bream (Acanthopagrus butcheri).
−
−
The area is also a drought refuge for local
waterbirds and a stop-over point for migratory
shorebirds. Threatened species of waterbirds
recorded in the area include the Cape Barren
Goose, Cereopsis novaehollandiae (Sv) and
Musk Duck, Biziura lobata (Sv). A total of 10
species of waterbirds have been recorded in
the area. Lloyd and Balla (1986) considered
this an area of outstanding environmental
value and recommended that it be given status
as a wetland reserve. The Spencer Gulf region
has been identified as an area of international
importance for shorebirds by Watkins (1993).
Tumby Bay (Salt Creek) has been identified as
a wetland of national importance (see ANCA
1996). Tumby Bay is a large intertidal wetland
of extensive saltmarsh and high quality
mangrove areas with two main tidal inlet
channels (First and Second Creeks).
Numerous small drainage channels extend
from these creeks throughout the extensive
samphire flats. The area provides a good
example coastal habitat, which has been
considerably reduced in many parts of Eyre
Peninsula (ANCA 1996). The area comprises
a wide range of habitats including estuarine,
supratidal (particularly mangroves and
samphires)
and
marine
environments
(intertidal and subtidal).
The wetland
provides large areas of mangrove (12 ha),
algae and seagrass habitats where various fish
species feed and spawn. Coastal vegetation
includes chenopod communities on the sand
dunes, mangrove and samphire flats fringing
the channels and tidal inlets, with Halosarcia
sp. and saltbush in less damp areas. The
subtidal region is dominated by dense seagrass
meadows, comprising Posidonia australis,
P.sinuosa, Halophila ovata and the brown
alga, Scaberia agardhii. Threatened species
of waterbird include the Eastern Curlew,
Numenius madagascariensis (Sv) and the
Fairy Tern, Sterna nereis (Sv). A total of 22
waterbird species have been recorded, 5 listed
under international treaties. Common bird
species include: Black Swan, Australian
Pelican, White-faced Heron, and cormorants.
Migration stopovers include 5 species of
migrant shorebirds. A total of 10 species of
fish have been recorded, including an
extremely large number of juvenile fish. The
Spencer Gulf region has been identified as an
area of international importance for shorebirds
by Watkins (1993).
−
Tumby Island Conservation Park: on the
Register of the National Estate.
Islands of Recognised Conservation Value
−
The offshore islands in this region represent
significant breeding sites for the rare
Australian Sea Lions (Neophoca cinerea) in
South Australia. Breeding colonies of the rare
Australian Sea Lion have been recorded on
Dangerous Reef (East Rock and West Reef)
(275 pups, estimated population 1,323),
Albatross (12 pups, estimated population 58),
English (40 pups, estimated population 192),
and also, the Gambier Isles (see Gambier
Biounit).
−
Breeding possibly occurs on Lewis, Smith
Rock and Buffalo Reef and the Neptune Isles
(Gales et al. 1994). Haul out and basking sites
also occur on Williams, Thistle, Hopkins,
Smith, Little, and Langton Islands, and the
Neptune and Gambier Isles (see Gambier
Biounit) (Watts & Ling 1985, Gales et al.
1994).
Of particular significance is
Dangerous Reef which supports the third
largest breeding population of sea lions in the
world, after the North and South Pages
(SANPWS 1990, Gales 1990).
−
While the largest breeding colonies of New
Zealand Fur Seals (Arctocephalus forsteri in
South Australia and Australia occurs in this
region (eg. Neptune Islands), within this
biounit, only haul out and basking sites have
been
recorded
(Albatross
Island)
(Shaughnessy et al. 1994).
−
Lincoln National Park. This park includes
most of the Jussieu Peninsula, together with
the following offshore islands - Rabbit,
Bickers, Owen, Little, Lewis, Hopkins, Smith,
Albatross, Curta Rocks and Liguanea. All the
offshore islands support very large breeding
populations of Short-tailed Shearwaters
(Puffinus tenuirostris). Smith Island also has
a breeding colony of the Flesh-footed
Shearwater (Puffinus carneipes), which was
first discovered in 1982 (Robinson & Heard
1985). On Curta Rocks there are large
breeding colonies of the Little White-faced
Storm Petrel (Pelagadroma marina). The
islands and the mainland coast also support
significant breeding populations of the Whitebellied Sea Eagles (Haliaeetus leucogaster)
Page 95
SPENCER GULF REGION – JUSSIEU BIOUNIT
and Ospreys (Pandion haliaetus). Many of
the islands in this group support breeding or
haul out sites for New Zealand Fur Seals and
rare Australian Sea Lions (Neophoca cinerea).
−
Sir Joseph Banks Group Conservation Park.
The islands of this park are particularly noted
for their bird populations. The islands form an
important refuge for the 76 recorded species,
of which 22 are known to breed on the islands.
They are considered the most important
breeding area in winter in South Australia for
the Cape Barren Goose (Cereopsis
novaehollandiae), supporting a stable
breeding population of approximately 1500,
out of a State population of 3,500-4,000
(Robinson et al. 1982, Robinson & Delroy
1986). White-faced Storm Petrels breed in
their burrows on many of the islands while
large breeding colonies of Black-faced Shags
(Leucocarbo fuscescens) occur on Winceby
and English Islands. The islands are also
reknown for significant colonies of rare
Australian Sea Lions. Dangerous Reef and
English Island are of particular significance as
breeding sites, however many of the other
islands are used as haul out and basking sites
(see above). In order to minimise disturbance
to breeding colonies of sea lions and shags,
public access is restricted to English Island,
Winceby Island, Dangerous Reef, Buffalo
Rock, Seal Rock, Buffalo Rocks and Smith
Rock (SANPWS 1990).
Several species of protected seabirds breed on
the islands, including Little Penguins
(Kirkeby, English, Duffield, Hareby, Roxby,
Blythe, Reevesby, Lusby, Partney and
Winceby Islands); White-faced Storm Petrels,
which breed in their burrows on many of the
islands (Kirkby, Sibsey, Hareby, Langton,
Blythe, Dalby, Reevesby, Lusby, Partney,
Winceby and Spilsby Islands); Black-faced
Cormorants
(Leucocarbo
fuscescens)
(Winceby, Sibsey and English Islands; the
`vulnerable' Fairy Terns (Kirkby, Langton and
Stickney Islands); Crested Terns (Kirkby,
Winceby Islands); Caspian Terns (Kirkby,
Blythe, Lusby, Roxby, and Partney Islands);
Silver Gulls (Marum, Blythe, Duffield,
Stickney, Sibsey Island); and Pacific Gulls
(Marum, Reevesby, Langton, Roxby, Duffield,
Stickney, Sibsey, English, Kirkeby Islands)
(Copley 1996).
−
Black Tiger Snakes (Notechis ater) are found
on Hareby, Roxby and Reevesby Islands.
While Reevesby Island sand flats at Moreton
Bay contain a variety of seagrasses, molluscs,
polychaetes, crustaceans. A variety of birds
feed in the shallows of these sand flats such as
the Sooty Oyster-Catcher.
Zeidler and
Gowlett
(1985)
described
seventeen
interesting and rare species of marine
Mollusca from the Sir Joseph Banks Islands.
Some of these include:
−
Brechites (Foegia) veitchi (a bivalve of the
family Clavagellidae) found in sand amongst
sparse seagrass and rubble. Commonly found
just north of Marum Island and between
Winceby Island and Reevesby Island in depths
of 6-12m.
−
Rare species of Myadora pervalida (bivalve of
the family Myochamidae).
−
An uncommon species found in sand patches
amongst seagrass Posidonia just north of
Marum Island and southeast of Winceby
Island is Semele monilis (bivalve of the family
Semelidae).
−
Very rare species of Phalium adcocki found in
sand pockets adjacent to reefs (gastropod of
the family Cassidae).
−
Undescribed species of octopus including a
very large gelatinous specimen with a 2 m arm
span.
In addition to the wildlife, one of the greatest
assets of the Sir Joseph Banks Group of islands
is considered to be its pristine, natural beauty
(Robinson et al. 1982). The park is on the
Register of the National Estate.
−
Dangerous Island and Reef. This system of
reefs lies approximately 25 km offshore and is
one of the three major sites for breeding of the
rare Australian Sea Lions in South Australia
(along with the Pages and Seal Bay, Kangaroo
Island). Surveys since 1975 have revealed a
population on these reefs ranging between 10
and 600 animals (SANPWS 1990). In 1990, a
total of 424 animals, including 236 pups were
recorded on East, Main and West Reefs (Gales
1990).This makes Dangerous Reef the third
largest breeding colony for this species in
South Australia (after the colonies on North
and South Pages). This area is also nationally
and internationally recognised for the
occurrence of White Sharks (Carcharodon
carcharias). Black-faced Cormorants, Pacific
Gulls, Silver Gulls breed on Dangerous Island
(Copley 1996).
Page 96
SPENCER GULF REGION – JUSSIEU BIOUNIT
−
1.2
Seagrass Meadows
2
The seagrass meadows of this biounit represent
the third largest areas in Spencer Gulf. These
extensive seagrass meadows flourish in the
shallow waters, generally in waters less than
15m, and provide the basis for the significant
productivity of the region in terms of fisheries
and prawn production. Seagrasses cover a total
area of approximately 5,512 km2 in Spencer
Gulf, of which 4138 km2 is located in northern
Spencer Gulf (ie. north of Point Riley).
Together, the seagrasses of Spencer Gulf
represent 57% of the total area of seagrasses
recorded in South Australia (ie. 9,612 km2).
Most of the seagrasses in the gulf are located in
the central northern reaches of the gulf (ie.
Yonga Biounit, 248,596 ha), in the Tiparra Reef
region (ie. Tiparra Biounit, 83,912 ha) and the
Port Lincoln region (ie. Jussieu Biounit, 56,956
ha).
2.1
Physical
Geological Monuments
−
Memory Cove: charnockitic rocks.
Register of the National Estate.
−
Kirton Point (Port Lincoln): coastal outcrops.
On the Register of National Estate as part of
Lincoln National Park.
−
Cape Donington: palaeodunes and coastal
basement platform. On the Register of the
National Estate.
On the
Sir Joseph Banks Group
The presence of abundant amphibolite, a darkgreen metamorphic rock, rich in iron and
magnesium silicate minerals particularly in
Winceby and Reevesby Islands.
OTHER VALUES
Commercial Fisheries
Port Lincoln is the major centre for commercial
fishing in Spencer Gulf. Major single species
fisheries which operate out from Port Lincoln
include: Western King Prawn, Abalone, Southern
Bluefin Tuna and the Southern Rock Lobster.
There is also an extensive marine scalefish fishery
in this region which targets, among other species,
Snapper, King George Whiting and Shark.
Western King Prawn
This biounit is located within the waters of the
Spencer Gulf prawn fishery, which comprises 39
license holders (ie. Boats). All vessels fish within
the waters of Spencer Gulf biounits (ie. Jussieu,
Dutton, Franklin, Yonga, Tiparra, Wardang,
Pondalowie, Spencer). In 1995/96 and 1996/97 a
total of 1811598 and 1,646,799 kg was caught for
this fishery, with a total effort of 27,025 and 25,369
hours, respectively (or 79.78% and 81.37% of the
total catch for Western King Prawn in South
Australian waters).
Southern Rock Lobster
In 1995/96 and 1996/97 a total of 11 and 12
licensed operators fished in the Jussieu Biounit (ie.
Fishing Zone 30), catching approximately 7,671
and 3,673 kg of lobsters, respectively (or 0.15%
and 0.07% of the total catch for Southern Rock
Lobster in South Australian waters). No lobsters
were caught during this same period for inshore
regions of this biounit, ie. Proper, Boston, Louth
and Peake bays, from Cape Donington to Point
Bolingbroke (ie. Fishing Zone 31).
Abalone
The Jussieu Biounit is a major region for both, the
Blacklip Abalone and Greenlip Abalone fishery in
South Australia. In 1994/95 and 1995/96 a total of
74,076 and 59,262 kg of Greenlip was harvested
within this region (ie. MapCode 18C-H, J-L, 19AE, Thorny Passage, Thistle Island, Dangerous
Reef), and represented 32.6% and 26.3% of the
total Greenlip Western Zone catch (or 19.66% and
15.83% of the total catch for Greenlip in South
Australian waters). In 1994/95 and 1995/96 a total
of 15,120 and 16,336 kg of Blacklip was harvested
within this region, and represented 4.9% and 5.9%
of the total Blacklip Western Zone catch (or 3.06%
and 3.53% of the total catch for Blacklip in South
Australian waters).
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SPENCER GULF REGION – JUSSIEU BIOUNIT
The Sir Joseph Banks Group is not a major area for
commercial abalone harvesting, (ie. MapCode
20B). No Blacklip Abalone were harvested from
this region (ie. MapCode 20B) during 1994/95 and
1995/96.
Greenlip Abalone figures are not
available due to confidentiality constraints.
Marine Scalefish Fisheries
This biounit represents one of the major regions for
the marine scalefish industry in South Australia.
During 1995/96 and 1996/97, 72 and 69
commercial licence holders (made up of Marine
Scalefish, Restricted Marine Scalefish and
Northern Zone Rock Lobster licence categories)
caught commercial marine scalefish species from
the offshore waters of the Jussieu Biounit (ie.
Fishing Zone 30), respectively. License holders
expended approximately 2,122 and 2,148 boat days
effort fishing these waters during 1995/96 and
1996/97, respectively. The marine scalefish catch
for this region (ie. Fishing Zone 30) represented
931,386 kg in 1995/96 and 1 716,478 kg in
1996/97(or 8.96% and 16.93% of the total catch for
the marine scalefish fishery in South Australian
waters).
Similarly, fishing activity in the inshore waters of
this biounit, ie. Proper, Boston, Louth and Peake
bays, from Cape Donington to Point Bolingbroke
(ie. Fishing Zone 31) is also high. During 1995/96
and 1996/97, 66 and 50 commercial licence holders
(made up of Marine Scalefish, Restricted Marine
Scalefish and Northern Zone Rock Lobster licence
categories) caught commercial marine scalefish
species from the inshore waters of the Jussieu
Biounit (ie. Fishing Zone 31), respectively. License
holders expended approximately 1,687 and 1,753
boat days effort fishing these waters during
1995/96 and 1996/97, respectively. The marine
scalefish catch for this region (ie. Fishing Zone 31)
represented 697,608 kg in 1995/96 and 1 195,206
kg in 1996/97(or 6.71% and 11.79% of the total
catch for the marine scalefish fishery in South
Australian waters).
−
2.2
Port Lincoln: 17 Abalone, 26 Western King
Prawn, 35 Southern Rock Lobster (working
west of Eyre Peninsula, 18 restricted marine
scalefish, 71 unrestricted marine scalefish, 5
miscellaneous.
−
Tumby Bay: 4 restricted marine scalefish, 9
unrestricted marine scalefish.
Aquaculture
This coastal biounit is a major region of sea-based
aquaculture activity in South Australia. At present,
this region is the only place in South Australia
where commercial Southern Bluefin Tuna farming
occurs. In this type of fish "farming" wild-caught
juvenile tuna are grown out or fattened to maturity
in sea-based cages. There are currently 6 approved
20 hectare lease sites for caged farms in Boston
Bay (Port Lincoln), one of which is a tourist farm.
Each lease site accommodates a maximum of 6
individual cages. However, there is currently a
proposal to increase the number of lease sites in
this region to 9 (ie. a maximum of 54 cages).
In addition to fish farming, there are presently 2
Pacific Oyster leases in southern Louth Bay, and 2
land-based Abalone farms in Louth Bay which
remove waters from Louth Bay. An oyster lease
application is currently pending for Proper Bay.
The
Lower
Eyre
Peninsula
Aquaculture
Management Plan (Aquaculture Group, PIRSA
1997) proposes the following level of aquaculture
development in this region:
Louth Bay Policy Area
−
Louth Bay Management Zone (Point Boston to
Peake Point) - licenses will not be considered
for intertidal, oyster, mussels or finfish
aquaculture development in this zone.
Licenses will be considered for a maximum of
50 ha of aquaculture (abalone, finfish) in this
zone.
−
Tod River Management Zone (coastal waters
adjacent Tod River estuary) – Licenses will be
considered for a maximum of 35 ha of
shellfish culture in this zone.
−
Peake Bay Management Zone (Peake Point to
Point Bolingbroke) – Licenses will be
considered for a maximum of 30 ha of
aquaculture (excluding finfish, oyster or
mussel culture).
−
Rabbit Island Tuna Farming Zone (defined
waters west of Rabbit Island) - Licenses will
be considered for a maximum of 120 ha of
tuna culture within this zone.
Although license holders are not restricted to
fishing in this biounit, the following licenses are
registered in this area:
−
Louth Bay: 1 unrestricted marine scalefish.
Page 98
SPENCER GULF REGION – JUSSIEU BIOUNIT
−
Rabbit Island Management Zone (remaining
offshore waters from Cape Donington, to Point
Boston to Point Bolingbroke) – tuna farming is
currently being trialed in this area. Licenses
will be considered for a maximum of 80 ha of
aquaculture development within this zone.
Port Lincoln Policy Area
−
Bickers Islands Aquaculture Zone – 60 ha of
aquaculture (tuna, mussels) leases currently
operating in this zone. Licenses will be
considered for a maximum of 40 ha of tuna
culture and 20 ha of R&D shellfish culture
within this zone.
−
Proper Bay Management Zone – oyster hatchery
at Louth Bay. Licenses will be considered for a
maximum of 50 ha of R&D shellfish culture
and 2 ha of R&D oyster culture within this
zone.
−
Rotten Bay Aquaculture Zone – 28 ha of tuna
culture currently operating within this zone.
Licenses will be considered for a maximum of
20 ha of tuna culture and 8 ha for a singlecage finfish site for tourism.
−
Boston Bay Aquaculture Zone – 150 ha of
leases (mostly shellfish) currently approved in
this zone. Licenses will be considered for a
maximum of 150 ha of aquaculture
development within this zone, comprising 60
ha of R&D mussel culture, 5 ha of R&D rock
lobster, 20 ha for R&D aquaculture, 15 ha
tuna farming research, and 50 ha of
aquaculture other than rock lobster or mussel
culture.
−
Boston Island East Tuna Farming Zone – 80
ha of leases currently approved in this zone.
Licenses will be considered for a maximum of
80 ha of aquaculture development within this
zone, comprising 60 ha of tuna culture, and 20
ha of finfish culture.
−
Boston Island West Aquaculture Zone – 120
ha of tuna culture currently approved in this
zone. Licenses will be considered for a
maximum of 264 ha of aquaculture
development within this zone, comprising 240
ha of tuna culture, 20 ha of finfish culture, and
4 ha of R&D rock lobster culture.
−
Lincoln National Park Zone – Licenses will
not
be
considered
for
aquaculture
development within this zone.
−
Port Lincoln Navigation Zone (remaining
waters within Port Lincoln) - Licenses will not
be considered for aquaculture development
within this zone.
No marine-based aquaculture current exists in the
Thorny Passage region (ie. Cape Catastrophe to
Cape Donington). The Lower Eyre Peninsula
Aquaculture Management Plan (Aquaculture Group,
PIRSA 1997) proposes minimal aquaculture
development in this region:
Thorny Passage Policy Area
−
Grindal Island Management Zone (waters of
northern Grindal Island and western Taylor
Island) – licenses will not be considered for
abalone aquaculture development in this zone.
A total of R&D permits (maximum area of 2
ha) will be considered for a maximum of 6ha
of rock lobster aquaculture in this zone.
−
Thorny Passage Management Zone (remaining
waters of Thorny Passage, from Cape
Catastrophe to Cape Donington) - licenses will
not be considered for abalone aquaculture
development in this zone. One R&D permit
(maximum of 3 tuna farm sites) will be
considered to investigate the impacts of tuna
farming in this zone.
There is presently no aquaculture activity in the Sir
Joseph Banks region.
The Spencer Gulf
Aquaculture Management Plan (PIRSA 1996)
recommends no aquaculture development in this
region:
Sir Joseph Banks Policy Area
Sir Joseph Banks Zone (waters surrounding
the Sir Joseph Banks Group of islands) –
zoned to preserve existing values and uses,
particularly conservation values. Licenses
will not be considered for aquaculture
development within this zone.
2.3
Recreation and Tourism
Fishing
−
Port Lincoln - Sleaford Bay: boat, jetty and
shore fishing. Major species: King George
Whiting, Sand Flathead, Yelloweye Mullet,
Australian Salmon, Snapper, Snook, Garfish,
Blue Swimming Crab, Tommy Rough and
Southern Calamari.
Page 99
SPENCER GULF REGION – JUSSIEU BIOUNIT
−
Tumby Bay: boat, jetty and shore fishing.
Major species: King George Whiting, Sand
Flathead, Yelloweye Mullet, Australian
Salmon, Snook, Garfish, Blue Swimming
Crab, Tommy Rough and Southern Calamari.
−
There is an artificial reef near Port Lincoln (a
sunken tug vessel, `Bronze Wing').
the colony is out of synchronisation with the
Seal Bay (Kangaroo Island) population
(SANPWS 1990).
Both populations are
presently being studied by researchers from
SANPWS.
−
Dangerous Reef is also becoming recognised,
both nationally and internationally, as one of
the major sites in the world for research into
White Sharks (Carcharodon carcharias).
There is presently an ongoing tagging project
being conducted jointly by fisheries
researchers and researchers from the
international, Cousteau Society.
−
In addition to Dangerous Reef, researchers
from the SANPWS regularly conduct surveys
of Australian Sea Lion and New Zealand Fur
Seal colonies in this region, particularly on the
offshore islands.
−
Port Lincoln Marine Science Centre is a
cooperative research centre, located on the
shore of Kirton Point, Port Lincoln. The
Centre is administered by Flinders University
of South Australia, and contains research
laboratories and facilities for staff and students
of the university and also, for lease. The
centre currently contains research staff and
postgraduate students from the South
Australian Research and Development
Institute (SARDI) and Flinders University.
The Centre at present is currently utilised for
research and monitoring of commercial
fisheries (such as Abalone, Southern Rock
Lobster), and also, sea-based aquaculture
(such as the farming of Southern Blue Fin
Tuna in Boston Bay).
−
Other fisheries research in this area includes,
regular catch and effort monitoring of the
major commercial fisheries in the region
(Western King Prawn and marine scalefish);
regular research and monitoring of larval fish
stocks; regular research and monitoring of
Blacklip and Greenlip Abalone field stocks.
Tourism
−
Offshore islands: the following areas are
popular for SCUBA diving and recreational
fishing (including Abalone and Southern Rock
Lobster) - Hopkins and Thistle Islands, West
Bay, Gambier Islands (Wedge Island), Sir
Joseph Banks Group of Islands, and the
Althorpe Islands. Access to these islands is
through charter companies such as Failie
Charters, as well as by private vessels.
−
SCUBA diving: Mittlers Cove (north western
corner of Thistle Island), Taylors and Hopkins
Island (Thorny Passage), Redbanks Spot 2
(Whalers Way), Wanna (south of Port
Lincoln),
Snowman
(Memory
Cove),
Donnington Rocks, the shipwreck `Degei’
(northern side of Donnington Island), Tumby
Bay jetty are all recognised dive spots in this
region and listed in `Dive South Australia: The
Best Dive Sites in South Australia’ (Diving
Industry Association of South Australia).
−
Dangerous Reef: this reef which lies
approximately 25 km offshore, is home to
Australia's largest Australian Sea Lion colony
and famous for its Great White Sharks.
Cruises to the reef depart from the Lincoln
Cove Marina.
−
Lincoln National Park: scenic qualities,
wilderness areas, historical areas, camping,
fishing, SCUBA diving.
−
Tumby Bay: camping, fishing.
2.4
−
Scientific Research and Education
Dangerous Reef is home to the third largest
breeding population of Australian Sea Lions in
the world (after the colonies on North and
South Pages). Surveys since 1975 have
revealed a population ranging between 10 and
600 animals. In a 1989 census, a total of 470
animals, including 141 pups were recorded
(SANPWS 1990). In 1990, a total of 424
animals, including 236 pups were recorded
(Gales 1990). The 18 month breeding cycle of
2.5
Adjacent Land Use
National and Conservation Parks
−
Sir Joseph Banks Group Conservation Park
(2,033 ha): all the islands of the Sir Joseph
Banks Group, with the exception of Spilsby
Island, fall within the park (SANPWS 1990).
Reevesby Island, the largest within the park
was the centre of agricultural pursuits in the
island group prior to their acquisition.
Page 100
SPENCER GULF REGION – JUSSIEU BIOUNIT
−
Tumby Island Conservation Park (35 ha).
−
Gambier Islands Conservation Park (64 ha):
comprises three islands and islets of the
Gambier Group, North Island, SW Rocks and
Peaked Rocks. Wedge Island, the main island
of the Gambier Group is held in freehold title
and is run as a tourist resort.
−
Lincoln National Park (29 060 ha): includes
most of the Jussieu Peninsula, together with
the following offshore islands - Rabbit,
Bickers, Owen, Little, Lewis, Hopkins, Smith,
Albatross, Curta Rocks and Liguanea.
Agriculture/Industry
Apart from land reserved as National or
Conservation Parks, most adjacent coastal land in
this biounit is developed for agricultural purposes.
Of particular note however, are the large shipping
facilities which occur off Port Lincoln; the 2 landbased Abalone farms in Louth Bay; and the
passenger launch to Boston Island, which is a fullyoperational sheep station.
−
Memory Cove-West Point and the Lincoln
National Park is significant in the history of
South Australian exploration through its
association with the voyage of Matthew
Flinders in 1802. A memorial on Stamford
Hill in the park commemorates Flinders' visit
to the area while the Cape Catastrophe,
Memory Cove area was the scene of the most
tragic incident of Flinders' circumnavigation
of Australia.
−
An old whaling station is located on Thistle
Island.
Shipwrecks
−
`City of Adelaide' (1854-1954): a Historic
Shipwreck declared under the South
Australian Historic Shipwrecks Act 1981.
The vessel, a steel, hydraulically propelled
lifeboat, beached at Porter Bay, Port Lincoln
in 1954. In 1985 the hull was removed from
Porter Bay and placed within the Axel
Stenross Maritime Museum at Port Lincoln.
Urban Centres
−
Port Lincoln (population 11,552).
Port
Lincoln has a permanent coastal mooring
facility for recreational and commercial craft.
−
Tumby Bay (population 996).
2.6
Features
Significant Cultural and Historical
Aboriginal
−
In the Port Lincoln region both, woven
wooden fishtraps, located in tidal channels, as
well as stone walled traps, have been recorded
(Martin 1988).
−
Point Bolingbroke: Aboriginal fish traps and
campsites (Martin 1988).
−
Billy Light Point: Aboriginal fish trap (Martin
1988).
European
Page 101
SPENCER GULF REGION – JUSSIEU BIOUNIT
3
−
Marine Reserves
None
−
Marine Parks
None
−
breeding colonies of New Zealand Fur Seals
and Australian Sea Lions, Register of the
National Estate-Lincoln National Park),
practicality
(accessibility,
insulation,
compatibility-adjacent to Lincoln National
Park, Sleaford Mere Conservation Park).
CURRENT CONSERVATION STATUS
OF THE JUSSIEU BIOUNIT
Netting Closures
Port Lincoln (all waters west of a line from
Point Bolingbroke to Cape Donnington).
−
Tod River (all waters of the Tod River and
Spencer Gulf within a radius of 200 m of the
mouth).
−
Tumby Bay (waters within a line drawn from
a point on the mainland adjacent to Tumby
Island to the southern tip of Tumby Island
then following the high water mark on the
eastern coast to a point on the north eastern
side to a point on the mainland 2.5km north of
the jetty, also all waters within a 500 m radius
of the mouth of Second Creek, south of
Tumby Bay).
4
AREAS OF HIGH CONSERVATION
VALUE IN THE JUSSIEU BIOUNIT
Sir Joseph Banks Group and Dangerous Reef
−
Prime IUCN Conservation Values: rare and
endangered species/habitats, aesthetic values,
biodiversity, social values (IUCN Category IB).
IUCN Identification Criteria: naturalness (not
subjected to human-induced change), ecological
(ecological integrity, diversity of marine
habitats, key breeding sites for Cape Barren
Goose, White-faced Storm Petrels, Black-faced
Shags, significant breeding and haul out sites
for Australian Sea Lions-Dangerous Reef,
English Island, Langton Island, Buffalo Reef,
Smith Rock, haul out sites for New Zealand Fur
Seals-Albatross
Island,
White
Shark
populations), economic (tourism-dive and
fishing charters, marine scalefish fisheries),
social (recreation, aesthetic values), scientific
(Dangerous Reef-key research site for
monitoring of White Shark populations,
Australian Sea Lions), national (national
importance for breeding colonies of Australian
Sea Lions, Register of the National Estate-Sir
Joseph Banks Group), practicality (insulation,
compatibility-adjacent to Sir Joseph Banks
Conservation Park).
Lincoln National Park-Thorny Passage
−
Peake Bay - Point Bolingbroke
Prime IUCN Conservation Values: rare and
endangered
species/habitats,
aesthetics,
biodiversity, cultural values (IUCN Category
IB).
IUCN Identification Criteria:
naturalness (not subjected to human-induced
change), biogeographic (geological monument –
Cape Catastrophe, Memory Cove, Cape
Donington), ecological (significant breeding
and haul out sites for New Zealand Fur SealsLiguanea Island, Low Rocks, Albatross Island,
Williams Island, Curta Rocks, Cape Rock,
breeding and haul out sites for Australian Sea
Lions-Liguanea Island, Curta Rocks, Cape
Rock, Williams, Smith, Little, Hopkins, Lewis,
Thistle, Albatross Islands, White Shark
populations, breeding sites for Short-tailed
Shearwater, Flesh-footed Shearwater, Little
White-faced Storm Petrel, White-bellied Sea
Eagle, Ospreys), economic (tourism-dive and
fishing charters, significant area for Greenlip
Abalone, Blacklip Abalone, Southern Rock
Lobster), social (recreation, aesthetic values,
whaling stations-Thistle Island, Sleaford Bay,
Memory
Cove,
historic
shipwrecks`Investigator’), national (national importance of
−
Prime IUCN Conservation Values: cultural
values, biodiversity, social values (IUCN
Category III). IUCN Identification Criteria:
naturalness, (not subjected to human-induced
change), ecological (ecological integrity,
diversity of marine habitats, extensive seagrass
meadows, reefs, nursery, feeding areas for
economic species-marine scalefish), economic
(marine scalefish fisheries, tourism), social
(Point Bolingbroke-aboriginal fish trap complex
and campsites, recreation), practicality
(accessibility).
Salt Creek-Tumby Bay-Tumby Island
−
Prime IUCN Conservation Values: education,
biodiversity,
rare
and
endangered
species/habitats, social, cultural values (IUCN
Category II). IUCN Identification Criteria:
naturalness (not subjected to human-induced
change), biogeographic (representative marine
habitats), ecological (diversity of coastal and
marine habitats, mangroves, samphires,
Page 102
SPENCER GULF REGION – JUSSIEU BIOUNIT
seagrass meadows, estuarine function, nursery,
feeding areas for economic species-Western
King Prawn, marine scalefish, threatened
waterbird species - Eastern Curlew, Fairy Tern,
seabirds - Black Swan, Australian Pelican,
White-faced
Heron,
and
Cormorants),
economic (marine scalefish fisheries, tourism),
social (aboriginal fish trap complex, recreation,
education, mangrove board walk-Tumby Bay),
national (Wetland of National ImportanceTumby Bay, Register of the National EstateTumby Island Conservation Park), practicality
(insulation, accessibility, compatibility-adjacent
to Tumby Island Conservation Park).
Proper Bay-Porter Bay-Spalding Cove
−
Prime
IUCN
Conservation
Values:
biodiversity, social, cultural values (IUCN
Category II). IUCN Identification Criteria:
biogeographic (representative marine habitats),
ecological (diversity of marine habitats,
extensive seagrass meadows, estuarine function,
nursery, feeding areas for economic speciesmarine scalefish, threatened waterbird species –
Cape Barren Goose, Musk Duck), economic
(marine scalefish fisheries, tourism), social
(aboriginal fish traps, recreation), national
(potential for listing on the Register of the
National Estate), practicality (accessibility,
compatibility-adjacent to Lincoln National
Park).
Tod Estuary (Louth Bay)
Prime
IUCN
Conservation
Values:
biodiversity, social, cultural values (IUCN
Category II). IUCN Identification Criteria:
biogeographic (representative marine &
estuarine habitats, one of the few true estuaries
on the Eyre Peninsula), ecological (diversity of
coastal and marine habitats, mangroves,
samphires, seagrass meadows, estuarine
function, nursery, feeding areas for economic
species-marine scalefish, threatened waterbird
species – Cape Barren Goose, Musk Duck),
economic (marine scalefish fisheries, tourism),
social (aboriginal fish traps, recreation),
national (Wetland of National Importance-Tod
River wetland system, potential for listing on
the Register of the National Estate), practicality
(accessibility, compatibility-adjacent to Tod
River wetland system).
Page 103
SPENCER GULF REGION – DUTTON BIOUNIT
XI
MARINE BIOGEOGRAPHY AND CONSERVATION VALUES OF THE
DUTTON BIOUNIT
This biounit extends from Salt Creek (near Tumby Bay) to Cape Driver (Arno Bay) on the western side of
central Spencer Gulf and covers an area of 255,443 ha. The biounit faces southeasterly into Spencer Gulf.
subdominants. Rock surface dominated by the
encrusting and articulated coralline algae (eg.
Amphiroa) and the prostrate brown alga,
Lobophora variegata.
MARINE BIOGEOGRAPHY
1
OCEANOGRAPHY
This region forms the central western section of
Spencer Gulf and has an overall easterly
orientation. Consequently, it is a zone of low wave
energy with prevailing offshore winds.
2
GEOLOGY
AND
GEOMORPHOLOGY 18
•
Seagrass
−
On sandy substrates, subtidal communities
dominated by Amphibolis antarctica in
shallow waters (6m) and Posidonia sinuosa in
deeper waters. Extensive meadows occur
south of Port Neill, and north of Lipson Island.
COASTAL
Lipson Cove shingle ridge is backed by minor dune
transgression and fronted by an 80m wide beach. A
barrier-cum-tombolo backed by a single shingle ridge
has developed in the lee of Lipson island.
−
Port Neill consists of a narrow transgressive barrier
backed by tidal flats.
MARINE CONSERVATION VALUES
3
BIOLOGY
Major Inshore Habitats
−
Major intertidal habitats in the region include
mostly low rocky shores and sandy beaches.
−
Of the total inshore subtidal habitats mapped
in this biounit (26,093 ha), seagrass meadows
comprise 25,706 ha (98.5%), reefs comprise
197 ha (0.8%), and sandy bottoms comprise
190 ha (0.7%).
Coastal and Offshore Islands (or Reefs)
1 SIGNIFICANT
BIOLOGICAL/PHYSICAL
FEATURES
1.1
−
Major Benthic Communities
•
Macroalgal
−
18
On moderately exposed rocky coasts (ie. Port
Neill), sutidal communities dominated by
Ecklonia radiata and mixed fucoids,
comprising
Sargassum
linearfolium,
S.paradoxum, S.spinuligerum, S.lacerifolium)
with species of Cystophora (C. expansa,
C.monoliformis, and C.brownii) as
Lipson Island (Lipson Cove).
1.2
−
Biological
Lipson Island Conservation Park is a breeding
site for protected seabirds, including Little
Penguins, Black Faced Cormorants, Crested
Terns and the `vulnerable' Fairy Tern (Copley
1996). The park is on the Register of the
National Estate. Silver Gull breeding sites are
also located on Tumby Island, Lipson Cove,
and Lipson Island.
Physical
Not known.
From Eyre Peninsula Coast Protection District Study Report.
Page 104
SPENCER GULF REGION – DUTTON BIOUNIT
2
OTHER VALUES
2.1
Commercial Fisheries
Major single species fisheries which operate in this
region include: Western King Prawn. There is also
a marine scalefish fishery in this region which
targets, among other species, Snapper, King
George Whiting and Shark. No Southern Rock
Lobster and very little abalone is commercially
harvested in this region.
Western King Prawn
This biounit is located within the waters of the
Spencer Gulf prawn fishery, which comprises 39
license holders (ie. Boats). All vessels fish within
the waters of Spencer Gulf biounits (ie. Jussieu,
Dutton, Franklin, Yonga, Tiparra, Wardang,
Pondalowie, Spencer). In 1995/96 and 1996/97 a
total of 1,811,598 and 1,646,799 kg was caught for
this fishery, with a total effort of 27,025 and 25,369
hours, respectively (or 79.78% and 81.37% of the
total catch for Western King Prawn in South
Australian waters).
Abalone
Although license holders are not restricted to fishing
in this biounit, the following licenses are registered in
this area:
−
Tumby Bay: 4 restricted marine scalefish, 9
unrestricted marine scalefish.
−
Port Neill: 1 restricted marine scalefish, 3
unrestricted marine scalefish
2.2
No aquaculture development or activities current
occur in this region. However, the Spencer Gulf
Aquaculture Management Plan (PIRSA 1996)
recommends
the
following
aquaculture
development in the region:
Tumby Bay Policy Area
−
Offshore Tumby Management Zone (waters
offshore from Massena Bay) – zoned for
aquaculture development. Licenses will be
considered for a maximum of 60ha of finfish
culture within this zone.
−
Tumby Management Zone (inshore coastal
waters, within 1km of the coast, from Salt
Creek to south of Cape Driver, excluding
waters adjacent to Lipson Island Conservation
Park and waters surrounding Port Neill) –
zoned for future aquaculture development.
Licenses will be considered for a maximum of
30ha of aquaculture development within this
zone.
−
Port Neill Zone (all remaining waters, out to
3nm from coast, from Salt Creek to south of
Cape Driver) – zoned to preserve existing
values and uses.
Licenses will not be
considered for aquaculture development
within this zone.
Very little abalone is presently commercially
harvested within this biounit. (ie. MapCode 20A,
20C, Cape Donnington to Port Neill region). No
Greenlip Abalone was harvested in 1994/95. No
Blacklip Abalone was harvested within this region
during 1994/95 and 1995/96.
Marine Scalefish Fisheries
During 1995/96 and 1996/97, 25 and 30
commercial licence holders (made up of Marine
Scalefish, Restricted Marine Scalefish and
Northern Zone Rock Lobster licence categories)
caught commercial marine scalefish species from
the Dutton Biounit (ie. Fishing Zone 29),
respectively.
License holders expended
approximately 1249 and 1262 boat days effort
fishing these waters during 1995/96 and 1996/97,
respectively. The marine scalefish catch for this
region (ie. Fishing Zone 29) represented 35,347 kg
in 1995/96 and 52,710 kg in 1996/97(or 0.34% and
0.52% of the total catch for the marine scalefish
fishery in South Australian waters).
Aquaculture
2.3
Recreation and Tourism
Fishing
−
Tumby Bay: boat, jetty and shore fishing.
Major species: King George Whiting, Sand
Flathead, Yelloweye Mullet, Australian
Salmon, Snook, Garfish, Blue Swimming
Crab, Tommy Rough and Southern Calamari.
Tumby Bay is unique in the fishing world as
the `Gateway to the Group', the Sir Joseph
Banks Group of islands, which provide some
of the best cruising and fishing in South
Australia. First Creek is used frequently by
boat fishermen as an outlet channel to gain
access to the sea.
Page 105
SPENCER GULF REGION – DUTTON BIOUNIT
−
Port Neill: boat, jetty, and shore fishing.
Major species: King George Whiting, Sand
Flathead, Yelloweye Mullet, Australian
Salmon, Snapper, Snook, Garfish, Blue
Swimming Crab, Tommy Rough, Trevally and
Southern Calamari.
Tourism
−
Urban Centres
−
2.6
Features
SCUBA diving: Tumby Bay jetty, Lipson
Cove and Lipson Island (particularly the
northern side of the island) are all recognised
dive spots and are listed in `Dive South
Australia: The Best Dive Sites in South
Australia’ (Diving Industry Association of
South Australia).
Lipson Cove is also
suitable for snorkelling.
Aboriginal
Point Bolingbroke: Aboriginal fish traps and
campsites (Martin 1988).
−
Salt Creek: Aboriginal fishtrap complex.
European
Not known.
Tumby Bay: camping, fishing.
−
−
Port Neill: popular and safe swimming beach,
boating, holiday flats and shacks.
3
2.5
Research in this area includes, regular catch
and effort monitoring of the major commercial
fisheries in the region (Western King Prawn
and marine scalefish); regular research and
monitoring of larval fish stocks; regular
research and monitoring of Blacklip and
Greenlip Abalone field stocks.
Adjacent Land Use
National and Conservation Parks
−
Lipson Island Conservation Park (1 ha).
Agriculture/Industry
−
CURRENT CONSERVATION STATUS
OF THE DUTTON BIOUNIT
Scientific Research and Education
Tumby Bay mangrove boardwalk and
interpretation centre, is a key destination for
tourists and students (from local and regional
centres) interested in estuaries and the
mangrove environment. The boardwalk and
interpretation centre is located on First Creek
(in the township of Tumby Bay), and was
designed and established by local community
and LandCare groups within the Tumby Bay
region.
−
Significant Cultural and Historical
−
−
2.4
Tumby Bay (population 996). A boat harbour
channel was dredged in 1978 to connect the
township with First Creek, and serves as an
area to moor or launch boats.
Apart from land reserved as Conservation
Park, most adjacent coastal land in this biounit
is developed for agricultural purposes.
−
Marine Reserves
None
−
Marine Parks
None
−
4
Netting Closures
Port Neill (all waters west of a line from Cape
Burr to a point on the mainland 1.5km north of
the jetty).
AREAS OF HIGH CONSERVATION
VALUE IN THE DUTTON BIOUNIT
Lipson Cove-Lipson Island
−
Prime IUCN Conservation Values: rare and
endangered species/habitats, biodiversity (IUCN
Category IA). IUCN Identification Criteria:
naturalness (not subjected to human-induced
change), biogeographic (representative marine
habitats), ecological (diversity of marine
habitats, breeding sites for seabirds-Little
Penguins, Black Faced Cormorants, Silver
Gulls, Crested Terns and the `vulnerable'
Fairy Tern), economic (marine scalefish
fisheries, tourism), social (recreation),
national (Register of the National EstateLipson Island Conservation Park), practicality
(insulation, compatibility-adjacent to Lipson
Island Conservation Park).
Page 106
SPENCER GULF REGION – FRANKLIN BIOUNIT
XII
MARINE BIOGEOGRAPHY AND CONSERVATION VALUES OF THE
FRANKLIN BIOUNIT
This biounit extends from Cape Driver (Arno Bay) on the western side of central Spencer Gulf to Victoria Point,
near the mouth of Franklin Harbour and covers an area of 198,588 ha. The biounit faces southeast into Spencer
Gulf.
Port Gibbon is dominated by a beach fronted
stranded cliff. At Dutton River mouth, fluvial
deposits have been reworked into a 200m wide
foredune ridge plain.
MARINE BIOGEOGRAPHY
1
OCEANOGRAPHY
The coast experiences a slightly higher wave
energy with some sections also exposed to higher
velocity onshore (west to south westerly) winds.
2
GEOLOGY
AND
GEOMORPHOLOGY19
COASTAL
In summary, the coastal morphology is dominated
by low energy reflective beaches, backed by single
stable to semi-stable foredunes and fronted by
relatively narrow sandflats. In addition, rocky
coast with low cliffs occur along most of the coast,
often with beaches forming in small crenulations
and/or fronting the low cliffs. Some of the cliffs
are unprotected by beaches and are eroding. In
places they have irregular rocky strandflats up to
100m wide. This area represents the largest single
Holocene sediment sink on the Spencer Gulf coast.
Longitudinal Pleistocene dunes fronted by barrier
samphire flats intersect the coast south of Mokami.
The more protected Arno Bay contains extensive
backbarrier tidal flat deposits fronted by a beach to
foredune ridge transition. The bay entrance contains
ebb and flood tide delta deposits and a moderately
dynamic entrance.
Mills Beach, south of Point Gibbon is a higher
energy system, with a beach ridge to barrier
sequence underlain by shingle ridges and backed
by scarped conglomerates. The barrier is capped
by the most extensive dune transgression
encountered in the western Gulf, with some dunes
reaching up to 500m inland. Drifting over the last
40 years has resulted in some dunes moving up to
100m.
19
Franklin Harbour (80 km2) is a typical southern
Australian enclosed bay (after Roy 1984). It is a
barrier estuary type, the beach embayment being
blocked by a barrier to the north to Germein Point
and a barrier to the west from Lucky Bay. Both
barrier consist of foredune ridges with extensive
recurved spits extending well into the bay. At the
bay entrance, extensive ebb tide delta deposits (7
km2) occur with even more extensive deposits
within the bay itself. These delta deposits have
filled 50% of the bay and are composed of both
subaerial and subaqueous marine deposits, cut by
three major tidal channels.
Intertidal sandy-mud flats partially covered by
mangroves surround the bay shore, creeks and the lee
of the barrier and recurved spits of the harbour. In
places the mangroves are continuing to prograde into
the bay.
The major contributions to bay
sedimentation are the wave and tide induced ebb and
flood tide delta deposits, the wave and wind formed
barriers, and the intertidal mud and mangrove flat
deposits. Only one minor creek, Poodra Creek,
drains into the bay.
There is a continuous foredune ridge barrier
extending from Point Germein to The Knob. A steep
reflective beach indicates that waves rarely exceed
0.5m. South of Franklin Harbour, embayments of
varying size have acted as the main Holocene
sediment sinks, leading to the development of
barrier/back barrier deposits.
From Eyre Peninsula Coast Protection District Study Report.
Page 107
SPENCER GULF REGION – FRANKLIN BIOUNIT
3
BIOLOGY
Major Inshore Habitats
−
−
−
estuarine and mangrove area with associated
samphire flats and mudflats (Franklin Harbor);
sandy beaches; rocky shores; seagrasses.
Major intertidal habitats in the region include
bays (ie. mangroves, saltmarshes, intertidal
mudflats), sandy beaches and rocky shores.
Of the total inshore subtidal habitats mapped
in this biounit (142,066 ha), sandy bottoms
comprise 87,258 ha (61.4%), reefs comprise
39 361 ha (27.7%), and seagrass meadows
comprise 15,447 ha (10.9%).
Major Benthic Communities
•
−
•
−
Macroalgal
On moderately exposed rocky shores (eg.
Cape Driver, Arno Bay), subtidal macroalgal
communities are dominated by Ecklonia
radiata and mixed fucoids (eg. Sargassum
linearifolium, S.spinuligerum, S.lacerifolium
and S.distichum), with species of Cystophora
(C.expansa, C.moniliformis, C.brownii) as
sub-dominants. Rock surfaces are commonly
dominated by the prostrate understorey brown
algae, Lobophora variegata and encrusting
and articulated coralline algae (eg. Amphiroa
sp.).
Seagrass
Sandy sediments in this region are colonised
by Posidonia sinuosa and Amphibolis
antarctica in shallower waters. Extensive
meadows in Franklin Harbor and off Arno
Bay, south to Dutton Bay.
−
Coastal and Offshore Islands (or Reefs)
None.
−
Rivers/Estuaries
Franklin Harbour estuary.
MARINE CONSERVATION VALUES
1
1.1
SIGNIFICANT BIOLOGICAL/PHYSICAL
FEATURES
Biological
Coastal and Marine Wetlands of National
Importance
−
Franklin Harbour (and the Franklin Harbour
Conservation Park) has been recognised as a
wetland of national importance (see ANCA
1996). The harbour is a shallow almost totally
landlocked embayment with two entrance
points to the harbour and a long narrow sandy
peninsula, protecting the mouth of Franklin
Harbour, with four inner bay islands. The bay
provides habitat for migratory waders, and the
islands provide a safe roosting and feeding site
for seabirds. Threatened species include the
White-bellied
Sea
Eagle,
Haliaeetus
leucogaster (Sv) and the Musk Duck, Biziura
lobata (Sv). A total of 14 waterbird species
has been recorded; 4 listed under treaties.
Breeding colonies of Pied Cormorants,
Phalacrocorax varius and Black-faced
Cormorants, P.fuscescens occur with the bay,
and also, a breeding pair of the White-bellied
Sea Eagle. Caspian Terns breed on Entrance
Island (Copley 1996). White-faced Herons
and large flocks of Grey Teal feed in the tidal
shallows. The islands and the sheltered waters
on the harbour side of the Peninsula have a
low woodland of mangroves (Avicennia
marina) and a tidal saltmarsh. Dense beds of
seagrass meadows (ie. Posidonia sinuosa) are
widespread throughout the bay and are
important sites for spawning, breeding or
shelter for numerous fish species. The brown
alga, Scaberia agardhii, dominates rocky
areas within the bay. The estuary supports
substantial and diverse areas of wetland that
would provide habitat for estuarine and
offshore fish stocks. A total of 13 species of
fish have been recorded, including juvenile
King George Whiting, Garfish, Tommy
Rough, Snapper, Snook and Squid. The size
of the estuary and the extent and diversity of
its associated wetlands suggest that its
contribution to the ecology of Spencer Gulf
would be significant (Bucher & Saenger
1989). The park is on the Register of the
National Estate. The Spencer Gulf region has
been identified as an area of international
importance for shorebirds by Watkins (1993).
Page 108
SPENCER GULF REGION – FRANKLIN BIOUNIT
regions, due to the long history of trawling
activities in the gulf. The species is widely
distributed throughout the tropical IndoPacific, and occurs along the southern
Australian coast, most commonly in bays and
gulfs to a depth of about 25m.
Other Areas of Recognised Conservation
Significance
Arno Bay (Salt Creek). The mangrove
and tidal saltmarsh communities of Salt Creek
represent a significant and poorly represented
coastal landform in the eastern region of
lower Spencer Gulf. The tidal communities
which extend approximately 400 ha, are of
considerable ecological and economic
significance providing important nursery,
feeding and breeding areas for many
commercially and recreationally important
species of fish and crustacea, including King
George
Whiting,
Yellowfin
Whiting,
Southern Sea Garfish, and the Blue
Swimming Crab.
The geomorphological
significance of the extensive tidal flat and
dune structures have been recognised with the
nomination of this area as a `geological
monument’ (see below), while the presence of
an Aboriginal fishtrap complex provides
cultural significance to the region.
The
conservation significance of this ecosystem
was recognised with the purchase of this land
(with contains the majority of the creek and
entrance) by the Coast Management Branch
and Coast Protection Board, which purchased
the land to ensure the environmental integrity
of the area was protected against
inappropriate development.
While the
mangroves at present are generally healthy
along the tidal creek system, the lower section
of the creek appears to be under stress from
the effects of recreational activities (Burton
1984).
−
−
About half way along the Point Germein
Peninsula are mud flats covered by the bluegreen alga, Oscillatoria sp. forming
stromatolite-like mounds of sediment.
Although not as spectacular as the
stromatolites of Shark Bay, Western Australia,
they are nevertheless significant (Butler et al.
1975).
Old colonies of the coral, Plesiastrea
versipora is known to occur on reefs in some
areas of the central and northern Spencer Gulf
region. On a biological survey of Spencer
Gulf in 1995 by the South Australian Research
and Development Institute (SARDI), large
coral colonies up to 1.5 m high were located in
the Shoalwater Point to Arno Bay region.
Colonies of P.versipora, typically have polyps
usually coloured green to brown. While
colonies may be small and encrusting, massive
old colonies up to 3m in diameter are
occasionally found in deeper water or dredged
up by trawlers. In Spencer Gulf, there are
historical records of large colonies dredged up
by trawlers, and it is probable that old massive
colonies are rare and isolated in the gulf
1.2
Physical
Geological Monuments
−
2
Arno Bay: coastal landforms.
OTHER VALUES
2.1
Commercial Fisheries
Major single species fisheries which operate in this
region include: Western King Prawn. There is also
an extensive marine scalefish fishery in this region
which targets, among other species, Snapper, King
George Whiting and Shark. Trawling for Western
King Prawn occurs further away from the coast.
Western King Prawn
This biounit is located within the waters of the
Spencer Gulf prawn fishery, which comprises 39
license holders (ie. Boats). All vessels fish within
the waters of Spencer Gulf biounits (ie. Jussieu,
Dutton, Franklin, Yonga, Tiparra, Wardang,
Pondalowie, Spencer). In 1995/96 and 1996/97 a
total of 1,811,598 and 1,646,799 kg was caught for
this fishery, with a total effort of 27,025 and 25,369
hours, respectively (or 79.78% and 81.37% of the
total catch for Western King Prawn in South
Australian waters).
Abalone
Limited abalone is presently commercially
harvested within this biounit. (ie. MapCode 21J,
Arno Bay to Cowell region), but due to
confidentiality constraints these figures are not
available.
Marine Scalefish Fisheries
This biounit encompasses 2 fishing zones: Fishing
Zone 19 and Fishing Zone 20 (Franklin Harbour).
During 1995/96 and 1996/97, 10 and 7 commercial
licence holders (made up of Marine Scalefish, and
Restricted Marine Scalefish licence categories)
caught commercial marine scalefish species from
the waters of Franklin Harbour (ie. Fishing Zone
20), respectively.
License holders expended
approximately 447 and 322 boat days effort fishing
these waters during 1995/96 and 1996/97,
respectively. The marine scalefish catch for this
region (ie. Fishing Zone 20) represented 52,098 kg
in 1995/96 and 30,230 kg in 1996/97(or 0.50% and
Page 109
SPENCER GULF REGION – FRANKLIN BIOUNIT
0.30% of the total catch for the marine scalefish
fishery in South Australian waters). In the waters
outside Franklin Harbour (ie. Fishing Zone 19), 13
and 10 commercial licence holders fished during
1995/96 and 1996/97. License holders expended
approximately 608 and 468 boat days effort fishing
these waters during 1995/96 and 1996/97, with a
total catch of 17,709 kg and 15,119 kg, respectively
(or 0.17% and 0.15% of the total catch for the
marine scalefish fishery in South Australian
waters).
Although license holders are not restricted to fishing
in this biounit, the following licenses are registered in
this area:
−
−
−
2.2
Franklin Policy Area
−
Cleve Management Zone (coastal waters, out
to 3nm from the coast, from south of Cape
Driver to south of Point Gibbon, excluding the
waters of Arno Bay) – zoned for potential
aquaculture development. Licenses will be
considered for a maximum of 60ha of
aquaculture development within this zone,
following the successful completion of an
R&D program.
−
Port Gibbon Management Zone (coastal
waters, out to 3nm from the coast, from
Poverty Bay to Germein Point, excluding 1km
zone of coastal waters from Point Gibbon to
Germein Point) – zoned for potential
aquaculture development. Licenses will be
considered for a maximum of 40ha of
aquaculture development within this zone,
excluding 1km seaward of .
−
Shoalwater Point Management Zone (coastal
waters, out to 3nm from the coast, from
Germein Point to northern boundary of
Munyaroo Conservation Park) – zoned for
potential aquaculture development. Licenses
will be considered for a maximum of 40ha of
aquaculture development within this zone.
Arno Bay: 2 restricted marine scalefish
Mt Dutton Bay: 1 restricted marine scalefish
Cowell: 1 restricted marine scalefish, 12
unrestricted marine scalefish.
Aquaculture
Franklin Harbour is a major site for intertidal
oyster culture in South Australia. There are
currently 114.5 ha of approved commercial oyster
leases and one R&D finfish lease within the bay.
The bay has been divided into 2 aquaculture
management zones: the North Eastern Basin (2 400
ha) and the South Western Basin (approximately
2,200 ha). The majority of approved leases are in
the South Western Basin, which has a virtual
complete cover of seagrass. The Franklin Harbour
Aquaculture Management Plan (1995) recommends
the following aquaculture development within the
harbour:
2.3
Fishing
−
Cowell, Lucky Bay, Franklin Harbor: boat,
jetty, and beach fishing. Major species: King
George Whiting, Yellowfin Whiting, Sand
Flathead, Yelloweye Mullet, Australian
Salmon, Snapper, Snook, Garfish, Blue
Swimming Crab, Tommy Rough, Trevally,
Toothbrush Leatherjacket and Southern
Calamari.
−
Arno Bay: boat, jetty, and shore fishing.
Major species: King George Whiting,
Yellowfin Whiting, Sand Flathead, Yelloweye
Mullet, Australian Salmon, Snapper, Snook,
Garfish, Blue Swimming Crab, Tommy
Rough, Trevally and Southern Calamari.
−
There is an artificial reef near Port Neill
(sunken vessel).
Franklin Harbour Zone
−
Licenses will be considered for a maximum of
119.5 ha of oyster culture within this zone.
−
Applications for relocation of leases within a
subzone or from the South Western Basin to
the North Eastern Basin will be considered.
No applications for relocation to the South
Western Basin will be considered.
−
Licenses will be considered for a maximum of
5ha of culture of non-filter feeding species,
upon successful completion of an R&D
program.
No aquaculture development or activities currently
occur in this region outside Franklin Harbour.
However, the Spencer Gulf Aquaculture
Management Plan (PIRSA 1996) recommends the
following aquaculture development in the region:
Recreation and Tourism
Page 110
SPENCER GULF REGION – FRANKLIN BIOUNIT
Tourism
−
−
2.4
−
−
2.5
2.6
Features
SCUBA diving: Redbanks (north of Arno
Bay) is a recognised reef dive and listed in
`Dive South Australia: The Best Dive Sites in
South Australia’ (Diving Industry Association
of South Australia). Redbanks consists of a
reef running from shore out to two reefs
running parallel to the coast. The dive (down
to 9m), suitable in most weather conditions,
consists of swim throughs, bommies and
undercuts with many varieties of fish life
inhabiting the reef.
Arno Bay: boating.
Scientific Research and Education
Arno Bay (Salt Creek) is the site of a proposed
coastal wetland interpretative trail, to be
established with funding assistance from
CoastCare and local council. The mangrove
forests and extensive coastal saltmarshes
adjacent to Salt Creek, and also the nearshore
reefs of Arno Bay, are presently the site of
significant recreational activity, including
canoeing, swimming and fishing. The lower
sections of the creek appear to be under stress
from the effects of recreational activity
(Burton 1984).
Fisheries research in this area includes, regular
catch and effort monitoring of the major
commercial fisheries in the region (Western
King Prawn and marine scalefish); regular
research and monitoring of larval fish stocks;
regular research and monitoring of Blacklip
and Greenlip Abalone field stocks.
Adjacent Land Use
Aboriginal
−
Mills Beach by Point Gibbon: Aboriginal
fishtrap.
−
Franklin Harbor & Searle Hill: only 2
outstanding examples of stone barrier fishtraps
in the Mid Eyre Peninsula region.
−
3
Franklin Harbour Conservation Park (1,334
ha).
Agriculture/Industry
−
Most adjacent land in this biounit is used for
agriculture.
Urban Centres
−
−
Cowell (population 692).
Port Neill (population 510).
European
Not known.
CURRENT CONSERVATION STATUS
OF THE FRANKLIN BIOUNIT
−
Marine Reserves
None
−
Marine Parks
None
−
Netting Closures
Arno Bay (all waters west of a line from the
land 200 m north of the end of the jetty due
south to a point known as South Point on Cape
Driver).
−
Cowell, Franklin Harbour (all the waters of
Franklin Harbour situated north west of a line
from Victoria Point to Germein Point).
4
AREAS OF HIGH CONSERVATION
VALUE IN THE FRANKLIN BIOUNIT
National and Conservation Parks
−
Significant Cultural and Historical
Arno Bay
−
Prime IUCN Conservation Values: education,
social values, biodiversity (IUCN Category III).
IUCN Identification Criteria: naturalness (not
subjected
to
human-induced
change),
biogeographic (geological monument-Arno Bay,
representative marine habitats), ecological
(range of marine habitats, mangroves,
saltmarshes, estuarine function, significant
nursery, feeding area for economic speciesWestern King Prawn, marine scalefish),
economic (marine scalefish fisheries, tourism),
social
(recreation-kayaking,
education),
practicality (insulation, accessibility).
Page 111
SPENCER GULF REGION – FRANKLIN BIOUNIT
Mills Beach-Franklin Harbor
−
Prime
IUCN
Conservation
Values:
biodiversity, social values, rare and endangered
species/habitats, cultural values, (IUCN
Category II). IUCN Identification Criteria:
naturalness (not subjected to human-induced
change, adjacent to intact terrestrial
catchment), biogeographic (representative
marine habitats), ecological (diversity of
marine habitats, mangroves, seagrasses,
nursery, feeding areas for economic species –
Western King Prawn, marine scalefish,
stromatolites, threatened seabirds - Whitebellied Sea Eagle, breeding colonies of Pied
Cormorants,
Black-faced
Cormorants,
Caspian
Terns,
ecological
integrity),
economic
(marine
scalefish
fisheries,
tourism), social (aboriginal fish traps,
recreation), national (Register of the National
Estate-Franklin
Harbour),
practicality
(insulation,
accessibility,
compatibilityadjacent to Franklin Harbour Conservation
Park).
Page 112
SPENCER GULF REGION – YONGA BIOUNIT
XIII
MARINE BIOGEOGRAPHY AND CONSERVATION VALUES OF THE YONGA BIOUNIT
This biounit extends from Victoria Point (near the mouth of Franklin Harbor) to Point Lowly on the western
side of Spencer Gulf to, Ward Point and Point Riley on the eastern side of the gulf, and covers an area of
423,556 ha. The biounit occupies the central northern waters of Spencer Gulf.
MARINE BIOGEOGRAPHY
Lucky Bay has a foredune ridge backed by a saline
flat that becomes flooded during storm surges.
1
In the vicinity of Lowly Point (and also, in the
northern, more estuarine part of the Gulf), strong
tidal currents have scoured the channel floor and
produced 200-500m wide belts of megaripples
orientated parallel to the channel margins.
OCEANOGRAPHY
Predominantly low wave energy. Slightly higher
wave energy occurs south of Shoalwater Point,
where the coast faces the strong south to southwesterly winds and waves as well as occasional
ocean swell.
3
The northern reaches of Spencer Gulf is an area of
low to very low wave energy.
BIOLOGY
Major Inshore Habitats
The extreme tidal range at Port Pirie is 3.1m with a
maximum range over a single tidal cycle of 2.9m.
−
Major intertidal habitats in the region include
mangroves, low rocky shores, and some sandy
beaches.
2
−
Of the total inshore subtidal habitats mapped
in this biounit (420,365 ha), seagrass meadows
comprise 248,596 ha (59.1%), sandy bottoms
comprise 161,715 ha (38.5%), and reefs
comprise 10,054 ha (2.4%).
GEOLOGY
AND
GEOMORPHOLOGY20
COASTAL
This section of coast has a uniform orientation and
exposure to the predominantly low wave energy
gulf, coupled with a low gradient Pleistocene
calcareous surface mantled by east-west trending
stable longitudinal dunes.
Coastal geomorphology is dominated by beach
ridge plains averaging 730 m in width, fronted by
wide inter- to subtidal sand flats. The beaches are
capped with low vegetated dunes and backed by
wide, low inter to supratidal flats covered by
samphire vegetation. Mangroves grow in the tidal
creeks and occasionally on the open coast.
South of Shoalwater Point, the coast faces strong
south to southwesterly winds and waves as well as
occasional ocean swell, producing a higher energy
shoreline with foredune ridges. The shoreline
consists of a wide intertidal sandflat which grades
into seagrass meadows. Steeper gradients occur as
the shoreline progrades seaward into deeper water.
20
Major Benthic Communities
•
Macroalgal
−
On rocky shores (ie. Shoalwater Point),
subtidal
communities
are
commonly
dominated by a mixed red algal assemblage,
dominated by Osmundaria and to a lesser
extent, Cladurus elatus, Dictymenia sonderi,
Botrycladia and also, the brown algae,
Caulocystis and Sargassum spinuligerum. At
Point Lowly, subtidal community dominated
by Hammer Oysters, Scaberia agardhii,
mixed-Cystophora species (ie. C.botyroides,
C.expansa,
C.polycystidea),
Lobophora,
Caulocystis and Sargassum linearifolium.
From Eyre Peninsula Coast Protection District Study Report.
Page 113
SPENCER GULF REGION – YONGA BIOUNIT
•
−
Extensive Mangrove and Tidal Wetlands
Seagrass
Extensive areas of seagrass occur in this
region, and comprise some of largest seagrass
meadows recorded in South Australia
(representing 29.2% of the total area of
seagrass recorded in the State).
Sandy
sediments in this region (eg Middle Bank) are
commonly dominated by Posidonia sinuosa
and P.angustifolia in deeper waters and
Amphibolis antarctica in shallower waters.
−
Coastal and Offshore Islands (or Reefs)
Weerona Island (Port Pirie).
−
−
−
Rivers/Estuaries
First - Seventh Creek (Port Pirie).
Port Davis Creek (south of Port Pirie).
Fisherman Creek (Port Broughton).
−
This biounit contains some of the largest areas
of temperate tidal wetlands and mangroves in
South Australia (and Australia). Spencer Gulf
(along with Gulf St Vincent) contains some of
the most extensive areas of mangrove forests
and tidal wetlands in South Australia (and the
largest areas of temperate mangroves in
Australia) (Edyvane 1996). Associated with
the mangrove habitats are the biologically rich
mud flats, coastal saltmarshes and seagrasses.
Together, these communities provide key
habitats for waterfowl and waders, and
important feeding, breeding and nursery areas
for economically important species of fish and
crustaceans (eg. Western King Prawn, King
George Whiting, Southern Sea Garfish).
Mangrove and saltmarsh communities along
the South Australian coast total approximately
82,000 ha, with the largest communities
occurring in Spencer Gulf (46,000 ha) and
Gulf St Vincent (20,000 ha). Other substantial
communities occur in lower Spencer Gulf
(6,000ha), on the west coast of Eyre Peninsula
(9 000 ha) and on Kangaroo Island (7 000 ha)
(DELM 1993). In Spencer Gulf, mangrove
forests occur north of Point Lowly, from Port
Pirie to Port Broughton, in Franklin Harbour,
and to a lesser degree near Tumby Bay.
−
The size of the Northern Spencer Gulf estuary
and its extent and diversity of its associated
wetlands suggest that its contribution to the
ecology of Spencer Gulf would be significant
(Bucher & Saenger 1989). This region
contains extensive areas of ecologically
significant wetland habitat comprising
mangroves, seagrass and tidal saltmarsh
communities, together comprising one of the
largest coastal wetland ecosystems in South
Australia:
−
Port Davis Creek - greater than 75% of the
catchment has been cleared of natural
vegetation. 12.07 km2 of intertidal sand/mud
flats; 16.59 km2 of mangroves; 13.41 km2 of
salt flats/salt marsh.
−
Third Creek (Port Pirie) - greater than 75%
of the catchment has been cleared of natural
vegetation. 0.89 km2 of intertidal sand/mud
flats; 1.93 km2 of mangroves; 9.80 km2 of salt
flats/salt marsh.
MARINE CONSERVATION VALUES
1
1.1
SIGNIFICANT
BIOLOGICAL
PHYSICAL FEATURES
AND
Biological
Seagrass Meadows
−
The seagrass meadows of this biounit represent
the largest areas in Spencer Gulf and also, South
Australia. These extensive seagrass meadows
flourish in the shallow waters, generally in
waters less than 15m, and provide the basis for
the significant productivity of the region in
terms of fisheries and prawn production. .
Seagrasses cover a total area of approximately
5,512 km2 in Spencer Gulf, of which 4138 km2
is located in northern Spencer Gulf (ie. north of
Point Riley). Together, the seagrasses of
Spencer Gulf represent 57% of the total area of
seagrasses recorded in South Australia (ie. 9,612
km2). Most of the seagrasses in the gulf are
located in the central northern reaches of the
gulf (ie. Yonga Biounit, 248,596 ha), in the
Tiparra Reef region (ie. Tiparra Biounit, 83,912
ha) and the Port Lincoln region (ie. Jussieu
Biounit, 56,956 ha).
Page 114
SPENCER GULF REGION – YONGA BIOUNIT
−
−
−
−
Second Creek (Port Pirie) - greater than 75%
of the catchment has been cleared of natural
vegetation. A sewage treatment works is
located on the coastal flats associated with the
estuary and could be a source of pollutants and
nutrients. 2.30 km2 of intertidal sand/mud
flats; 6.03 km2 of mangroves; 11.76 km2 of
salt flats/salt marsh.
First Creek (Port Pirie) - greater than 75% of
the catchment has been cleared of natural
vegetation. 8.04 km2 of intertidal sand/mud
flats; 11.59 km2 of mangroves; 9.93 km2 of
salt flats/salt marsh.
Whyalla-Cowleds Landing Aquatic Reserve
−
Munyaroo Conservation Park
−
Fisherman Creek (Port Broughton) - greater
than 75% of the catchment has been cleared of
natural vegetation. 6.75 km2 of intertidal
sand/mud flats; 8.42 km2 of mangroves; 13.25
km2 of salt flats/salt marsh.
The size of the wetland habitat in the WhyallaPirie Region and the extent and diversity of its
associated wetlands suggest that its
contribution to the ecology and fisheries
productivity of Spencer Gulf would be
significant (Bucher & Saenger 1989).
−
The mangrove and seagrass areas of Northern
Spencer Gulf constitute important nursery
areas for several commercial fish and
crustacean species caught both locally and in
the southern areas of Spencer Gulf.
In terms of overall fisheries production, the
northern reaches of Spencer Gulf (south of
Point Lowly) supports the largest Western
King Prawn (Penaeus latisulcatus) fishery in
the Australia. Some 1,500 tonnes of prawns,
valued at $20 million, are caught annually in
the region, which represents approximately
75% of the State's total prawn harvest.
Northern Spencer Gulf itself provides
approximately 45% of the State's marine
scalefish catch and more than 45% of the
State's blue crab catch, although the bulk of
the these catches occurs between Moonta and
Ward Spit.
Possible remnant South Australian population
of Brush-tailed Bettongs. It has a beach and
coastal dune system backed by samphire flats
and claypans. The park is on the Register of
the National Estate.
Seabirds
−
Nursery Areas for Economic Species
−
Major habitat types include samphire flats
which are flushed by extremely high spring
tides; intertidal mangrove area; intertidal sand
and mudflats; and subtidal seagrass meadows.
Outstanding features include the extensive
mangrove and seagrass areas which constitute
important nursery areas for several
commercial fish and crustacean species.
Several protected seabirds breed in the region,
including Pied Cormorants at Fisherman's
Creek, Shag Island (Port Broughton), the
mangrove creeks of Port Pirie, and Weerona
Island (Port Pirie); Caspian Terns at Ward Spit
(Point Germein); and the `vulnerable' Little
Tern at Ward Spit. Recent studies indicate
that the Little Tern may realistically be
regarded as endangered within South Australia
(Copley 1996).
Giant Cuttlefish
−
The reefs off Point Lowly have recently been
recognised as an area of major significance for
the spawning aggregations of the Giant
Cuttlefish (Sepia apama).
The Giant
Cuttlefish is the largest cuttlefish in the world
and is only found in southern Australian
waters. Females migrate to rocky areas to
mate and lay a few (<100) large eggs for one
season, and then die. The paucity of reef areas
in the Northern Spencer Gulf region probably
explain the unique aggregation of cuttlefish at
Point Lowly, which represents one of the few
rocky reef areas in the area. Cuttlefish require
hard surfaces on which eggs can be laid and
Cuttlefish probably migrate from wide area of
the gulf to Point Lowly (Mark Norman,
University of Melbourne, pers.comm.).
Page 115
SPENCER GULF REGION – YONGA BIOUNIT
Coral Colonies
−
1.2
Old colonies of the coral, Plesiastrea
versipora is known to occur on reefs in some
areas of the central and northern Spencer Gulf
region. On a recent biological survey of
Spencer Gulf by the South Australian
Research and Development Institute (SARDI),
large coral colonies up to 1.5 m high were
located in the Shoalwater Point to Arno Bay
region. Colonies of P.versipora, typically
have polyps usually coloured green to brown.
While colonies may be small and encrusting,
massive old colonies up to 3m in diameter are
occasionally found in deeper water or dredged
up by trawlers. In Spencer Gulf, there are
historical records of large colonies dredged up
by trawlers, and it is probable that old massive
colonies are rare and isolated in the gulf
regions, due to the long history of trawling
activities in the gulf. The species is widely
distributed throughout the tropical IndoPacific, and occurs along the southern
Australian coast, most commonly in bays and
gulfs to a depth of about 25m.
Physical
Geological Monuments
−
2
2.1
"Glensea" (10 km north of Shoalwater Point):
beach ridge plain. Its sequence is typical of
central Spencer Gulf. There are 8 ridges of
varying height and spacing extending 1,200m
inland from HWM. The sequence provides a
useful record of both Holocene sedimentation
and sea-level change in the central Spencer
Gulf region. It is well preserved and readily
accessible by vehicle.
OTHER VALUES
Commercial Fisheries
Western King Prawn is the major single species
fisheries in this region. There is also an extensive
marine scalefish fishery in this region which
targets, among other species, Snapper, King
George Whiting, Blue Swimmer Crab and Shark.
The region is of major importance for the marine
scalefish fishery, representing one of the most
significant fishing grounds in South Australia.
Trawling for Western King Prawn occurs further
away from the coast. No abalone is commercially
harvested within this region.
Western King Prawn
This biounit is located within the waters of the
Spencer Gulf prawn fishery, which comprises 39
license holders (ie. Boats). All vessels fish within
the waters of the Spencer Gulf biounits (ie. Jussieu,
Dutton, Franklin, Yonga, Tiparra, Wardang,
Pondalowie, Spencer). In 1995/96 and 1996/97 a
total of 1,811,598 and 1,646,799 kg was caught for
this fishery, with a total effort of 27,025 and 25,369
hours, respectively (or 79.78% and 81.37% of the
total catch for Western King Prawn in South
Australian waters).
Marine Scalefish Fisheries
This biounit encompasses one of the most
significant fishing grounds in South Australia for
the marine scalefish industry.
The biounit
encompasses 3 fishing zones: Fishing Zone 21, 22
and 23. During 1995/96 and 1996/97, 89 and 90
commercial licence holders (made up of Marine
Scalefish, and Restricted Marine Scalefish licence
categories) caught commercial marine scalefish
species from the southern waters of this biounit,
south of Wood Point, including Fishery Bay (ie.
Fishing Zone 22 and 23), respectively.
License holders expended approximately 5644 and
5496 boat days effort fishing these waters during
1995/96 and 1996/97, respectively. The marine
scalefish catch for this region (ie. Fishing Zones 22
and 23) represented 604,011 kg in 1995/96 and
599,758 kg in 1996/97(or 5.81% and 5.92% of the
total catch for the marine scalefish fishery in South
Australian waters).
In the northern waters of this biounit, from Wood
Point north to Point Douglas, including Germein
Bay and False Bay (ie. Fishing Zone 21), 57 and 61
commercial licence holders fished during 1995/96
and 1996/97. License holders expended
approximately 4,624 and 4,791 boat days effort
fishing these waters during 1995/96 and 1996/97,
with a total catch of 660,899 kg and 869,656 kg,
respectively (or 6.36% and 8.58% of the total catch
for the marine scalefish fishery in South Australian
waters). In total the marine scalefish catch for the
Yonga Biounit during 1995/96 and 1996/97
represented approximately 12.16% and 14.49% of
the total catch for the marine scalefish fishery in
South Australian waters.
Page 116
SPENCER GULF REGION – YONGA BIOUNIT
Although license holders are not restricted to fishing
in this biounit, the following licenses are registered in
this area:
−
Port Pirie: 2 Spencer Gulf Prawn, 6 restricted
marine scalefish, 20 unrestricted marine
scalefish, 1 experimental crab
−
Merninnie Landing: one unrestricted marine
scalefish
Whyalla: 5 restricted marine
unrestricted marine scalefish
2.2
scalefish,
22
−
Offshore Tickera Management Zone
(offshore waters, from 1km to 3nm
offshore, from Webling Point south to
Point Riley) – zoned for potential
aquaculture development. Licenses
will be considered for a total of 60ha
of aquaculture development within this
zone, excluding the culture of non-native
oyster species.
−
Aquaculture
Wallaroo Zone (remaining coastal waters,
from just north of Fisherman Bay, south to
Cape Elizabeth) – zoned to preserve existing
values and uses.
Licenses will not be
considered for aquaculture development
within this zone.
Present aquaculture activities in this region include:
the commercial culture of microalgae in extensive
pond systems to the north of Whyalla and a R&D
lease for the culture of finfish in sea cages in the
BHP marina.
2.3
The Spencer Gulf Aquaculture Management Plan
(PIRSA 1996) recommends the following
aquaculture development in the region:
−
Lucky Bay: boat and beach fishing. Major
species: King George Whiting, Yellowfin
Whiting, Sand Flathead, Yelloweye Mullet,
Australian Salmon, Snapper, Snook, Sweep,
Garfish, Blue Swimming Crab, Tommy
Rough, Trevally, Toothbrush Leatherjacket,
Silver Drummer and Southern Calamari.
−
Point Lowly (Whyalla): boat, shore and jetty
fishing. Major species: King George Whiting,
Sand Flathead, Yelloweye Mullet, Australian
Salmon, Snapper, Snook, Garfish, Blue
Swimming Crab, Tommy Rough, Trevally and
Southern Calamari.
−
There are artificial reefs located near Port
Pirie (tyre modules) and Port Germein (sunken
pipes). There are three artificial reefs near
Whyalla (tyre modules).
−
Port Pirie: boat, jetty and shore fishing. Major
species: King George Whiting, Yellowfin
Whiting, Black Bream, Sand Flathead,
Yelloweye Mullet, Australian Salmon,
Snapper, Mulloway, Snook, Garfish, Blue
Swimming Crab, Tommy Rough, Trevally and
Southern Calamari.
−
Port Broughton: boat, jetty and shore fishing.
Major species: King George Whiting,
Yellowfin Whiting, Sand Flathead, Yelloweye
Mullet, Australian Salmon, Snapper, Snook,
Garfish, Blue Swimming Crab, Tommy
Rough, Trevally and Southern Calamari.
Fishing
Whyalla-Pirie Policy Area
Murninnie Management Zone (waters 1km
offshore from Murninnie Beach) – zoned for
aquaculture development.
Licenses will be
considered for a maximum of 40ha of aquaculture
within this zone.
−
Northern Spencer Gulf Zone (all remaining
central northern gulf waters, from Murninnie
Beach east to south of Wood Point, and Point
Lowly to Ward Spit) – zoned to preserve
existing values and uses. Licenses will not be
considered for aquaculture development
within this zone.
Northern Yorke Peninsula Policy Area
−
Broughton Management Zone (3 areas, in the
waters of Port Broughton) – zoned for R&D
aquaculture development. Licenses will be
considered for a maximum of 10ha of
aquaculture development within this zone,
following the successful completion of a R&D
program.
Recreation and Tourism
Page 117
SPENCER GULF REGION – YONGA BIOUNIT
Tourism
−
−
−
−
−
2.4
−
−
2.5
Urban Centres
Lucky Bay: boating, holiday shacks.
Point Lowly (Whyalla): boating.
Whyalla, Point Lowly: boating.
Port Pirie: boating.
SCUBA diving: Point Lowly tyre reef is
recognised dive spot and listed in `Dive South
Australia: The Best Dive Sites in South
Australia’ (Diving Industry Association of
South Australia). The tyre reef is close to
shore and can be accessed via shore or via a
boat dive, and attracts Snapper and Long
Snouted Boarfish and other marine life.
−
−
−
2.6
Features
Significant Cultural and Historical
−
Not known.
3
CURRENT CONSERVATION STATUS
OF THE YONGA BIOUNIT
Scientific Research and Education
Port Pirie and the associated mangrove creeks,
tidal flats and nearshore seagrass meadows in
the region (from First Creek to Port Davis
Creek) have been the site of a major scientific
studies into the effects of heavy metals on
marine ecosystems (Ward et al. 1982, 1986,
Edyvane & Boxall 1996), and more recently
the effect of the `Era’ oil spill (Wardrop et al.
1993, Connolly & Jones 1996).
Fisheries research in this area includes, regular
catch and effort monitoring of the major
commercial fisheries in the region (Western
King Prawn and marine scalefish); and regular
research and monitoring of larval fish stocks.
−
Marine Reserves
Whyalla-Cowleds Landing (3,230 ha)
−
Marine Parks
None
−
Netting Closures
Germein Bay (all waters of Germein Bay
within a line from the mouth of Second Creek
northwards to a point in the bay, then north
westerly to Ward Spit light and east north east
to Ward Point).
−
Port Broughton, Fisherman Bay (all waters of
Fisherman Bay and Spencer Gulf east of a line
from the northern point of Fisherman Bay to
Shag Island then south to Webling Point)
4
AREAS OF HIGH CONSERVATION
VALUE IN THE YONGA BIOUNIT
Adjacent Land Use
National and Conservation Parks
−
−
Whyalla (population 26,900).
Port Pirie (population 15,114).
Both centres have permanent coastal moorings
for recreational and commercial craft.
Munyaroo Conservation Park (12,334 ha).
Munyaroo Conservation Reserve (7,200 ha).
Agriculture/Industry
−
Most adjacent land in this biounit is used for
agriculture, except for the predominantly
industrial cities of Whyalla and Port Pirie.
−
Algal culture industry situated near the
saltpans of Whyalla. It uses the waste water
from BHP steel factory.
−
Major port facilities occur at Whyalla and Port
Pirie.
Whyalla-Cowleds Landing
−
Prime
IUCN
Conservation
Values:
biodiversity, social, cultural values (IUCN
Category II). IUCN Identification Criteria:
biogeographic (representative marine habitats),
ecological (range of marine habitats, mangrove
forests, seagrass meadows, saltmarshes, nursery
areas, feeding areas for economic speciesWestern King Prawn, marine scalefish),
economic (marine scalefish fisheries, tourism),
social (recreation), scientific (prawn, marine
scalefish research and monitoring) national
(Register of the National Estate-Munyaroo
Conservation Park), practicality (insulation,
accessibility,
compatibility-adjacent
to
Munyaroo Conservation Park).
Page 118
SPENCER GULF REGION – YONGA BIOUNIT
Point Lowly
Prime
IUCN
Conservation
Values:
biodiversity, social values (IUCN Category II).
IUCN Identification Criteria: biogeographic
(rare habitats-reef habitats within a seagrass
dominated ecosystem), ecological (site of Giant
Cuttlefish spawning aggregations, nursery,
feeding and breeding areas for economic
species-Western King Prawn, marine scalefish),
economic (marine scalefish fisheries, tourism),
social (recreation, diving), scientific (prawn,
marine scalefish, research and monitoring),
national (potential for Register of the National
Estate).
Germein Bay–Port Davis-Fisherman Bay
−
Prime
IUCN
Conservation
Values:
biodiversity,
rare
and
endangered
species/habitats, social values (IUCN Category
IB).
IUCN Identification Criteria:
biogeographic (representative marine habitats,
largest areas of coastal and marine wetlands in
SA), ecological (range of marine habitats, large
areas of mangroves, seagrasses, saltmarshes,
numerous tidal estuaries – First, Second, Third,
Fourth, Fifth, Sixth, Seventh Creek, Port Davis
Creek, Fisherman Creek, key nursery, feeding
areas for economic species – Western King
Prawn, marine scalefish, breeding sites for
`vulnerable’ Little Tern, Caspian Tern, Pied
Cormorants), economic (marine scalefish
fisheries, tourism), social (recreation), scientific
(prawn, marine scalefish, mangrove, seagrass
research and monitoring), national/international
(international importance for shorebirds and
Wetland of National Importance-upper Spencer
Gulf wetlands, potential for RAMSAR listing),
practicality
(insulation,
accessibility,
compatibility-adjacent to Point Jarrold
Sanctuary).
Page 119
SPENCER GULF REGION – WINNINOWIE BIOUNIT
XIV
MARINE BIOGEOGRAPHY AND CONSERVATION VALUES OF THE WINNINOWIE
BIOUNIT
This biounit extends from Point Lowly (on the western side of Spencer Gulf) to Ward Point (on the eastern side
of Spencer Gulf), to Port Augusta, and covers an area of 55,266 ha. The biounit occupies the far northern
waters of Spencer Gulf.
MARINE BIOGEOGRAPHY
1
OCEANOGRAPHY
The far northern reaches of Spencer Gulf is an area
of very low wave energy.
The extreme tidal range at Port Augusta is 2.7 m
with a mean spring tidal range of 2.0 m.
High evaporation and limited freshwater inflow
produce salinities in excess of 40%.. Evaporation
results in the formation of ephemeral salt crusts on
supratidal flats. Temporal and spatial gradients
also exist in the water temperature which increases
about 200C from Lowly Point to Port Augusta, and
varies annually between 100C and 290C.
2
GEOLOGY
AND
GEOMORPHOLOGY21
The supratidal zone of the northern Gulf consists
mainly of bare carbonate flats which are
occasionally inundated by high spring or storm
tides (Gostin et al. 1984). They cover about 138
km2 or 7% of the total area. A few stranded beach
ridges and coastal dunes delineate the position of
former shorelines.
In water deeper than 10 m, over most of the Gulf,
the seafloor is smooth and is underlain by a thin
0.5-2m sheet of mud and shell. Two algal and three
animal assemblages in deeper water have been
described.
In the vicinity of Lowly Point and in the northern,
more estuarine part of the Gulf, strong tidal
currents have scoured the channel floor and
produced 200-500m wide belts of megaripples
orientated parallel to the channel margins.
COASTAL
Northern Spencer Gulf is the apex of an elongate
marine protrusion into arid continental Australia,
bordered by the industrial towns of Whyalla, Port
Pirie and Port Augusta. Shallow depths (less than
25 m) and a semi-arid environment have resulted in
a warm, saline body of water often referred to as an
`inverse estuary'.
Northern Spencer Gulf lies along a hinge zone
between two major geological provinces of Late
Precambrian age, the Adelaide Geosyncline to the
east, and the Stuart Shelf to the west.
3
Major Inshore Habitats
−
Major intertidal habitats in the region include
mangroves, saltmarshes, intertidal mudflats
and sandy shores.
−
Of the total inshore subtidal habitats mapped
in this biounit (54,211 ha), sandy bottoms
comprise 37,727 ha (69.6%), and seagrass
meadows comprise 16,484 ha (30.4%). No
significant reef areas are recorded in this
region.
The coastal geomorphology is that of wide
intertidal and supratidal areas, consisting of
mudflats, mangroves and samphire flats.
In the vicinity of Lowly Point and in the northern,
more estuarine part of the Gulf, strong tidal
currents have scoured the channel floor and
produced 200-500m wide belts of megaripples
orientated parallel to the channel margins.
21
BIOLOGY
Major Benthic Communities
•
−
Macroalgal
Limited rocky substrate is recorded in this
region.
From Eyre Coast Protection District Study Report.
Page 120
SPENCER GULF REGION – WINNINOWIE BIOUNIT
•
−
Seagrass
The shallow sublittoral zone of northern
Spencer Gulf is dominated by stands of
Posidonia australis and P.sinuosa with
subordinate
growth
of
Heterozostera
tasmanica, Amphibolis antarctica and
Halophila ovalis (Johnson 1982, Shepherd
1983, Gostin et al. 1984). The seagrass stands
occupy broad shallow platforms, particularly
along the eastern margin of the gulf, as well as
on and around discrete offshore banks. The
distribution of seagrass species with depth
varies considerably between locations.
Although P.australis may grow within the
intertidal zone to almost mean sea level,
massive growth predominates from between
spring low water level to about 4m depth.
Thereafter, P.sinuosa dominates to between 8
and 10 m depth (Shepherd 1983).
MARINE CONSERVATION VALUES
1 SIGNIFICANT
BIOLOGICAL
PHYSICAL FEATURES
1.1
−
Extensive mangrove and tidal wetlands. This
biounit contains the largest areas of temperate
tidal wetlands and mangroves in South
Australia (and Australia).
Spencer Gulf
(along with Gulf St Vincent) contains some of
the most extensive areas of mangrove forests
and tidal wetlands in South Australia (and the
largest areas of temperate mangroves in
Australia) (Edyvane 1996). Associated with
the mangrove habitats are the biologically rich
mud flats, coastal saltmarshes and seagrasses.
Together, these communities provide key
habitats for waterfowl and waders, and
important feeding, breeding and nursery areas
for economically important species of fish and
crustaceans (eg. Western King Prawn, King
George Whiting, Southern Sea Garfish).
Mangrove and saltmarsh communities along
the South Australian coast total approximately
82,000 ha, with the largest communities
occurring in Spencer Gulf (46,000 ha) and
Gulf St Vincent (20,000 ha). Other substantial
communities occur in lower Spencer Gulf
(6,000ha), on the west coast of Eyre Peninsula
(9,000 ha) and on Kangaroo Island (7,000 ha)
(DELM 1993). In Spencer Gulf, mangrove
forests occur north of Point Lowly, from Port
Pirie to Port Broughton, in Franklin Harbour,
and to a lesser degree near Tumby Bay.
−
The marine and coastal wetlands of upper
Spencer Gulf have been identified as a
wetland of national importance (see ANCA
1996). The upper Spencer Gulf region is an
inverse estuary containing shallow, saline
waters, and characterised by intertidal
mangrove forests, tidal sand and mudflats
(with some areas of shingle and sandy
beaches), dissected by a network of tidal
channels and creeks (eg. Chinaman Creek,
First-Seventh Creek, Port Davis Creek,
Fisherman Creek).
The seagrasses support a rich and diverse epibiota
characterised by red algae (King 1981).
Epibenthos and infauna found amongst seagrasses
in northern Spencer Gulf include crustaceans, the
large bivalves Pinna, Pecten, Ostrea and Katelysia
and numerous other molluscs (Shepherd 1983).
In the Point Lowly channel (at 20m), which
experiences strong tidal currents, the subtidal
community is animal-dominated, particularly
by Pinna, bryozoans, and sponges.
Rivers/Estuaries
−
(Far) Northern Spencer Gulf, an
`inverse' estuary that supports
extensive seagrass growths in waters
less than 10m.
−
Mambray Creek.
Biological
Coastal and Marine Wetlands of National
Importance
On the southern flank of the Yatala Harbour
channel several crescentic scours have been
observed. These are approximately 20-30 m wide
and have a depth of some 2m. They appear similar
to the "blowouts" reported by Shepherd and Sprigg
(1976) in the seagrass meadows of the adjacent
Gulf St Vincent.
−
AND
Page 121
SPENCER GULF REGION – WINNINOWIE BIOUNIT
The region includes the far northern reaches of
the gulf from Whyalla (on the eastern side of
Eyre Peninsula) to Port Broughton (on the
western side of Yorke Peninsula), and includes
the mangrove and coastal saltmarsh
communities of Whyalla, Blanche Harbour,
Port Augusta, Redcliff Point, Yalata Harbour,
Port Germein, Port Pirie south to Point Jarrold,
Fisherman’s Bay and Port Broughton. Below
sea level, the habitats are dominated by
extensive seagrass meadows in shallow waters
and silty habitats in deeper waters (Shepherd
1974, 1983). The region contains the largest
undisturbed stand of mangroves remaining in
South Australia (particularly at Redcliff and
Chinaman Creek) and the region is considered
to be one of the finest examples of a
subtropical marine and coastal ecosystem in
the southern hemisphere, containing the richest
and most diversified coastal flora in South
Australia (ANCA 1996). Large sand waves or
`megaripples’ characterise the deeper, channel
areas of the upper gulf (Shepherd 1983,
Shepherd & Hails 1984). The area has also
been identified as an area of international and
national importance for shorebirds by Watkins
(1993). Threatened species of waterbirds
include the Orange-bellied Parrot, Neophema
chrysogaster (Ne, Se), Hooded Plover,
Thinornis rubricollis (Nv, Sv), White-bellied
Sea-Eagle, Haliaeetus leucogaster (Sv),
Osprey, Pandion haliaetus (Sv), Little Egret,
Egretta garzetta (Sv), Eastern Curlew,
Numenius madagascariensis (Sv), Fairy Tern,
Sterna nereis (Sv), Slender-billed Thornbill,
Acanthiza iredalei rosinae (Sv), Eastern Reef
Egret, Egretta sacra (Sr), Spotted Crake,
Porzana tabuensis (Sr) and Australasian
Shoveler, Anas rhynchotis (Sr) (ANCA 1996).
A total of 67 species of waterbirds have been
recorded for the region: 19 are listed under
international treaties. A total of 20 species
have been recorded in the region, including the
only specimen of the Broadbill Swordfish,
Xiphias gladius, known to be caught in South
Australian waters.
Other notable fauna
recorded in the region include the Hawksbill
Turtle, Eretmochelys imbricata, dolphins and
occasional sightings of sea lions, and whales.
Seagrass Meadows
−
In upper Spencer Gulf, Johnson (1982)
recorded 48 "erect" species of Rhodophyta and
Phaeophyta epiphytic on Posidonia sinuosa
leaves. Shepherd (1983) recorded 4 species of
Chlorohpyta, 18 species of Phaeophyta and 62
species of Rhodophyta in the same area. The
extensive seagrass meadows in turn support a
prolific skeletal biota as infauna and epiphytes.
In addition, numerous bacteria, diatoms and
other micro-organisms are known to form thin
coatings over leaf blades (Kuo 1978).
Nursery Areas for Economic Species
−
The mangrove and seagrass areas of upper
Spencer Gulf constitute important nursery
areas for several commercial fish and
crustacean species caught both locally and in
the southern areas of Spencer Gulf. The size
of the estuary and its extent and diversity of its
associated wetlands suggest that its
contribution to the ecology of Spencer Gulf
would be significant (Bucher & Saenger
1989). The principal commercial species in
the region include the Southern Sea Garfish,
Hyporhamphus melanochir, King George
Whiting, Sillaginodes punctata, Snapper,
Chrysophrys auratus, Western Sand Whiting,
Sillago schomburgkii, Tommy Ruff, Arripis
georgiana,
Snook,
Sphyraena
novaehollandiae and Australian Salmon,
Arripis truttacea. A total of 11 species of
crustaceans have been recorded in the region;
the most common include the the Western
King Prawn, Penaeus latisulcaus, Blue
Swimmer Crab, Portunus pelagicus and Mud
Crabs, Helice haswellianus.
In terms of
overall fisheries production, the northern
reaches of Spencer Gulf (south of Point
Lowly) supports the largest Western King
Prawn (Penaeus latisulcatus) fishery in the
Australia. Some 1500 tonnes of prawns,
valued at $20 million, are caught annually in
the region, which represents approximately
75% of the State's total prawn harvest. Upper
Spencer Gulf itself provides approximately
45% of the State's marine scalefish catch and
more than 45% of the State's blue crab catch,
although the bulk of the these catches occurs
between Moonta and Ward Spit.
Upper Spencer Gulf is an inverse estuary that
supports extensive seagrass meadows in
waters less than 10m. Growth of Posidonia
species is particularly vigorous, with high leaf
blade production and turnover rates (West &
Larkum 1979). Shepherd (1983) estimates an
annual leaf blade productivity in excess of 9
kg/m2 in shallow water. The seagrasses
support a rich and diverse epibiota
characterised by red algae (King 1981).
Page 122
SPENCER GULF REGION – WINNINOWIE BIOUNIT
Relict Tropical Element in Marine Biota
−
The benthic flora and fauna of the northern
reaches of upper Spencer Gulf is characterised
by a significant and very distinctive, relict
tropical element (Shepherd 1983) and is
recognised as a distinctive biogeographical
region known as the `Northern Spencer Gulf
Bioregion' (IMCRA 1997). Although most of
the algal species recorded in Northern Spencer
Gulf have intermediate warm to cool
temperate affinities (occurring throughout the
southern Australian region), some algal
species, such as Sargassum decurrens and
Hormophysa triquetra, are nowadays only
distributed in tropical and subtropical regions.
Notwithstanding, other algal species, such as
Asparagopsis taxiformis and Platysiphonis
mutabilis, appear to have distinct warm
temperate affinities, occurring only westward
of the South Australian Gulfs. In addition to
these species, Beanland & Woelkerling (1982)
recorded a further four algal species, with
tropical
affinities,
on
mangrove
pneumatophores.
−
The presence of some coelenterates in upper
Spencer Gulf is also of special interest.
Echinogorgia sp. and Scytalium sp. appear to
be endemic in upper Spencer Gulf (Grasshoff
1982). Virgularia mirabilis, a cosmopolitan
species, is known in South Australia only from
this region (Utinomi & Shepherd 1982) and
Telest multiflora, a tropical species, is
recorded in southern Australia only in mid
and upper Spencer Gulf (Verseveldt 1982). In
addition, the ascidian, Sucozoa pedunculata is
known in southern Australian only from upper
Spencer Gulf and Investigator Strait (Kott
1972, 1975). These last four species except
for V.mirabilis, appear to have tropical
affinities suggesting that isolated populations
are confined to Gulf waters. In addition, a
number of species in other phyla newly or not
yet described are known only from upper
Spencer Gulf. They include the bryozoan,
Bugula sp., a flatworm, Ancoratheca
australiaensis
and
an
opisthobranch,
Discodoris. Further, the ophiuroid, Amphiura
trisacantha is apparently rare elsewhere
(Baker & Devaney 1981).
−
The benthic environment and the fauna of
upper Spencer Gulf differ markedly from
those of upper Gulf St Vincent, a region with
similar temperature and salinity extremes.
The latter region is generally shallow with
deeper, silty bottom dominated by a Pinnaholothurian assemblage whereas upper
Spencer Gulf has deeper channels, stronger
water currents and generally well sorted
medium to coarse shelly sands. Nowhere in
upper Spencer Gulf does Pinna bicolor
support the rich epizoic fauna described for
upper Gulf St Vincent. Of the 32 species
considered to be occasional to common in
upper Gulf St Vincent by Shepherd and Sprigg
(1976), only one echinoderm Goniocidaris
tubaria, two molluscs, Pinna bicolor and
Malleus meridianus, and one ascidian,
Polycarpa pedunculata occur in comparable
abundance in upper Spencer Gulf; the
remainder appear to be rare or absent. On the
basis of present knowledge of the fauna of the
Gulfs, Northern Spencer Gulf is impoverished
in terms of overall species richness but
relatively rich in species which are either
endemic or have tropical affinities.
Other Areas of Significance
−
Yatala Harbour Aquatic Reserve (1,426
hectares).
Samphire flats, flushed by
extremely high spring rides, intertidal sand
and mudflats; subtidal seagrass meadows;
coarse sand and shell channel areas.
−
Blanche Harbour-Douglas Bank Aquatic
Reserve (3,160 hectares). Intertidal mangrove
area; intertidal sand and mudflats; subtidal
seagrass meadows; coarse sand and shell
channel areas.
−
Winninowie Conservation Park (Chinamans
Creek). Pied Cormorants breed at Chinamans
Creek.
1.2
−
Physical
All of the far Northern Spencer Gulf region
can be considered as physically significant
owing primarily to its nature as an inverse
estuary which contributes to the biological
properties of the region.
Page 123
SPENCER GULF REGION – WINNINOWIE BIOUNIT
−
2
2.1
Sedimentologically, the seagrass meadow acts
as a major subtidal carbonate "factory", with
high rates of in-situ carbonate production and
post-mortem skeletal accumulation (Davies
1970, Patriquin 1972, Gostin et al. 1984).
Also trapped are terrigenous and aeolian
detrital grains, as well as both terrigenous and
calcareous muds. The Corallinaceae are
important carbonate producers, particularly
Lithothamnium, Jania and Corallina species.
Benthic and epiphytic foraminifers are also
important contributors to the sediment. Other
sessile and vagile epifauna which contribute to
bed sediment are encrusting bryozoa,
gastropods, hydroids, echinoderms and
ascidians.
OTHER VALUES
Commercial Fisheries
Major single species fisheries which operate in this
region include the Western King Prawn fishery.
There is also an extensive marine scalefish fishery
in this region which targets, among other species,
Snapper, King George Whiting and Shark.
Trawling for Western King Prawn occurs further
away from the coast. No abalone is commercially
harvested within this region.
Western King Prawn
This biounit is located within the waters of the
Spencer Gulf prawn fishery, which comprises 39
license holders (ie. Boats). All vessels fish within
the waters of the Spencer Gulf biounits (ie. Jussieu,
Dutton, Franklin, Yonga, Tiparra, Wardang,
Pondalowie, Spencer). In 1995/96 and 1996/97 a
total of 1,811,598 and 1,646,799 kg was caught for
this fishery, with a total effort of 27,025 and 25,369
hours, respectively (or 79.78% and 81.37% of the
total catch for Western King Prawn in South
Australian waters).
Marine Scalefish Fisheries
This biounit encompasses 2 fishing zones: Fishing
Zone 21 and 11. In the southern waters of this
biounit, from Wood Point north to Point Douglas,
including Germein Bay and False Bay (ie. Fishing
Zone 21), 57 and 61 commercial licence holders
fished during 1995/96 and 1996/97. License
holders expended approximately 4,624 and 4,791
boat days effort fishing these waters during
1995/96 and 1996/97, with a total catch of 660899
kg and 869,656 kg, respectively (or 6.36% and
8.58% of the total catch for the marine scalefish
fishery in South Australian waters). In the northern
waters of this biounit, north of Point Douglas (ie.
Fishing Zone 11), fishing effort is significantly
lower. A total of 7 and 6 commercial licence
holders fished approximately 209 and 130 boat
days effort fishing these waters during 1995/96 and
1996/97, with a total catch of 10829 kg and 11,730
kg, respectively (or 0.10% and 0.12% of the total
catch for the marine scalefish fishery in South
Australian waters.
Although license holders are not restricted to fishing
in this biounit, the following licenses are registered in
this area:
−
2.2
Port Augusta: 9 restricted marine scalefish, 5
unrestricted marine scalefish
Aquaculture
Present aquaculture activities in this region include:
R&D lease (30ha) for the culture of finfish in sea
cages at Fitzgerald Bay and in the outflow channel
of the Port Augusta power station, as well as on the
land adjacent to this. A single 792 ha lease
application in Fitzgerald Bay has recently been
lodged by the NSGAE.
The Spencer Gulf Aquaculture Management Plan
(PIRSA 1996) recommends the following
aquaculture development in the region:
Far Northern Spencer Gulf Policy Area
−
Fitzgerald Bay Management Zone (waters
within Fitzgerald Bay) – zoned for sustainable
aquaculture development. Licenses will be
considered for a maximum of 100ha of
aquaculture within development within this
zone.
−
Douglas Management Zone (coastal waters
north of Douglas Point, north to just south of
Douglas Bank Aquatic Reserve) – zoned for
R&D intertidal shellfish culture. Licenses will
be considered for a maximum of 10ha of
intertidal oyster culture within this zone, upon
successful completion of an R&D program.
−
Patterson Management Zone (coastal waters
of Port Patterson) – zoned for R&D
aquaculture development. Licenses will be
considered for a maximum of 16ha of R&D
aquaculture development. Aquaculture will be
restricted to Pacific Oyster culture within the
inlet channel of the Port Augusta Power
Station
and
aquaculture
requiring
supplementary feeding within the inlet and
outlet channel of the power station.
Page 124
SPENCER GULF REGION – WINNINOWIE BIOUNIT
−
Augusta Zone (all remaining waters, from
Point Lowly to Ward Spit, to Port Augusta, not
covered by above zones) – zoned to preserve
existing uses and values. Licenses will not be
considered for aquaculture development within
this zone.
−
Fisheries research in this area includes, regular
catch and effort monitoring of the major
commercial fisheries in the region (Western
King Prawn and marine scalefish); and regular
research and monitoring of larval fish stocks.
2.5
2.3
Adjacent Land Use
Recreation and Tourism
National and Conservation Parks
Fishing
−
−
−
2.4
−
−
−
Port Augusta: boat, jetty and shore fishing.
Major species: King George Whiting, Sand
Flathead, Yelloweye Mullet, Australian
Salmon, Snapper, Snook, Garfish, Blue
Swimming Crab, Tommy Rough, Trevally,
Southern Calamari, Mulloway and Yellowtail
Kingfish.
There are artificial reefs located near Port
Augusta (tyre modules), Port Pirie (tyre
modules), Port Germein (sunken pipes) and
Port Broughton (car bodies). There are three
artificial reefs near Whyalla (tyre modules).
−
Winninowie Conservation Park (Chinamans
Creek) (7,847 ha) (SANPWS 1996).
Point Jarrold Sanctuary.
Agriculture/Industry
−
Much of the adjacent land in this biounit is
used for agriculture.
−
Port Augusta is a major industrial centre with
port facilities.
Urban Centres
Tourrism
−
Port Augusta (population 15,291).
Port Augusta: boating.
−
Port Augusta has permanent coastal moorings
for recreational and commercial craft.
Scientific Research and Education
Chinaman’s Creek Research Station is situated
on the shores of Spencer Gulf, in the
Winninowie Conservation Park. The field
station encompasses both research facilities
and accommodation.
The field research
station was a major focus for marine studies in
northern Spencer Gulf, particularly in the
1970s, for a range of oceanographic,
geomorphological and marine ecological and
benthic studies. During the 1980s the field
station was utilised for ongoing climatological
and oceanographic monitoring, and also,
fisheries research into benthic infauna, Blue
Swimming Crabs, and a range of commercial
marine scalefish species. In recent years,
research activity at the station has declined,
however, ongoing meteorological and
oceanographic monitoring is still conducted.
Northern Spencer Gulf has been the subject of
major research and scientific investigations,
both geoscientific and biological, over several
decades.
−
Other Uses
Army Training Area (Fitzgerald Bay to Port
Augusta).
2.6
Features
Significant Cultural and Historical
−
Aboriginal
Fitzgerald Bay: Aboriginal fish trap.
−
European
Not known.
3
CURRENT CONSERVATION STATUS
OF THE WINNINOWIE BIOUNIT
−
−
Marine Reserves
Blanche Harbour-Douglas Bank (3,160 ha)
Yatala Harbour (1,426 ha)
−
Marine Parks
None
−
Netting Closures
Douglas Bank (all waters of Spencer Gulf
north of a line east west through the Douglas
Bank beacon).
Page 125
SPENCER GULF REGION – WINNINOWIE BIOUNIT
4
AREAS OF HIGH CONSERVATION
VALUE IN THE WINNINOWIE BIOUNIT
Far Northern Spencer Gulf
−
Prime IUCN Conservation Values: rare and
endangered
species/habitats,
aesthetics,
biodiversity, social values (IUCN Category IB).
IUCN Identification Criteria: naturalness (not
subjected
to
human-induced
change),
biogeographic (rare biogeographic qualitiessubtropical element in marine fauna and flora,
largest area of coastal and marine wetlands in
SA), ecological (essential ecological processes,
range of wetland habitats, large areas of
mangroves, seagrasses, saltmarshes, numerous
tidal estuaries, key nursery, feeding areas for
economic species – Western King Prawn,
marine scalefish, threatened waterbirdsOrange-bellied Parrot, Hooded Plover, Whitebellied Sea-Eagle, Osprey, Little Egret, Eastern
Curlew, Fairy Tern, Eastern Reef Egret, Spotted
Crake), economic (fisheries, tourism), social
(aesthetic values, recreation), scientific
(Chinaman’s
Creek
research
station,
ecological,
fisheries,
geomorphological
research and monitoring), national/international
(international importance for shorebirds and
Wetland of National Importance-upper Spencer
Gulf wetlands, potential for RAMSAR listing),
practicality (insulation, compatibility-adjacent
to Winninowie Conservation Park and Army
Training Area).
Page 126
SPENCER GULF REGION – TIPARRA BIOUNIT
XV
MARINE BIOGEOGRAPHY AND CONSERVATION VALUES OF THE
TIPARRA BIOUNIT
This biounit extends from Point Riley on the eastern side of central Spencer Gulf, to Island Point (near Port
Victoria) and covers an area of 243,228 ha. The biounit faces westerly into Spencer Gulf.
MARINE BIOGEOGRAPHY
1
−
OCEANOGRAPHY
This is a predominantly low to moderate wave
energy area.
Major Benthic Communities
•
2
GEOLOGY
AND
GEOMORPHOLOGY22
COASTAL
The west coast of Yorke Peninsula in Spencer Gulf
is more exposed than the east coast. Much of the
coast is comprised of long sandy beaches and shore
platforms associated with these, with a single dune
or narrow belt of dunes behind. Notable exceptions
are the limestone cliffs in the Pt Turton/Point
Souttar area; the rocky coastlines at Port Victoria,
Point Pearce and north of Point Riley; the clay
cliffs at Balgowan and Moonta Bay; the shallow
deeply indented bay at Port Broughton; and the low
calcrete cliffs to be found at various locations.
From Tickera to Point Riley there are stable clay or
limestone cliff slopes. At Wallaroo and North
Beach there is a wide dune belt followed by
aelonite and limestone cliffs from Wallaroo to the
northern end of Moonta Bay. Some tidal swamps
with mangroves and samphire flats occur at
Warburto Point.
Moonta Bay consists of a wide dune belt and
limestone cliffs.
3
BIOLOGY
Of the total inshore subtidal habitats mapped
in this biounit (103,185 ha), seagrass meadows
comprise 83,912 ha (81.3%), sandy bottoms
comprise 14,782 ha (14.3%), and reefs
comprise 4,491ha (4.4%).
−
•
−
Macroalgal
Subtidal rocky shore communities in this
region (eg. Point Riley) are dominated by
species of Sargassum (S.linearifolium,
S.podacanthum), with Scaberia agardhii as a
sub-dominant. The understorey is dominated
by the prostrate Lobophora variegata, and a
mixed-red algal community (Botrycladia,
Rhabdonia, Echinothamnion, Jeanneretia).
Seagrasses
Extensive seagrass meadows occur in
Wallaroo and Moonta Bay (eg. Tiparra reef).
Sandy sediments in this region are commonly
dominated by Posidonia sinuosa, Amphibolis
antarctica and Heterozostera tasmanica.
Coastal and Offshore Islands (or Reefs)
−
−
−
Riley Shoal, Moonta Shoal.
Tiparra Reef.
Bird Islands (Green Island).
−
Rivers/Estuaries
None.
Major Inshore Habitats
−
Major intertidal habitats in the region include
mostly low rocky shores, bays and sandy
beaches.
22
From Yorke Coast Protection District Study Report (Wynne
1980).
Page 127
SPENCER GULF REGION – TIPARRA BIOUNIT
MARINE CONSERVATION VALUES
1 SIGNIFICANT
BIOLOGICAL
PHYSICAL FEATURES
1.1
AND
Warburto Point
−
Biological
Tiparra Reef
Tiparra Reef is an extensive seagrass-reef
shoal system in Moonta Bay, that extends
along the western coastline of Yorke
Peninsula, from Cape Elizabeth to Warbuto
Point and Bird Islands. Like the seagrass-reef
shoal system of Orontes Shelf in Gulf St
Vincent, the calcreted Pleistocene shell bed
forms extensive flat rocky surfaces, or low
erosional escarpments and provides excellent
habitat for a diversity of marine life, including
sponges, ascidians, and reef molluscs, and is
also an outstanding mixed fishing ground.
The diversity and productivity of the area,
particularly on the reefs, is enhanced by the
tidal currents of the northern gulf. Tiparra
Reef is presently the major commercial
fishing ground for Greenlip Abalone (Haliotis
laevigata) in South Australia, with catches in
the area representing approximately 25-30%
of the total South Australian catch for this
species (or 65-80% of the total catch for the
Central Zone). A conservation reserve was
proposed for the reefs at Cape Elizabeth by
the former SA Department of Fisheries in
1980.
Bird Islands Conservation Park
−
−
The seagrass meadows of this biounit represent
the second largest areas in Spencer Gulf. These
extensive seagrass meadows flourish in the
shallow waters, generally in waters less than
15m, and provide the basis for the significant
productivity of the region in terms of fisheries
and prawn production. Seagrasses cover a total
area of approximately 5,512 km2 in Spencer
Gulf, of which 4,138 km2 is located in northern
Spencer Gulf (ie. north of Point Riley).
Together, the seagrasses of Spencer Gulf
represent 57% of the total area of seagrasses
recorded in South Australia (ie. 9,612 km2).
Most of the seagrasses in the gulf are located in
the central northern reaches of the gulf (ie.
Yonga Biounit, 248,596 ha), in the Tiparra Reef
region (ie. Tiparra Biounit, 83,912 ha) and the
Port Lincoln region (ie. Jussieu Biounit, 56,956
ha).
Consists of two small islands that provide an
important breeding and feeding ground for
bird life, particularly Pied Cormorants,
Crested Terns, Caspian Terns, Pacific Gulls
and Silver Gulls.
Tiparra and Cape Elizabeth
−
1.2
Reefs are known for their great diversity of
fish. A conservation reserve was proposed for
Cape Elizabeth in 1980.
Physical
Geological Monuments
−
2
2.1
Seagrass Meadows
Contains samphire flats and some mangroves
and supports a diverse bird population. It is an
important breeding and feeding ground for
bird life, particularly Pied Cormorants and
Caspian Terns.
Port Hughes-Port Moonta: basement rocks on
the foreshore of Moonta Bay. It is on the
Register of the National Estate.
OTHER VALUES
Commercial Fisheries
A wide variety of commercial fishing occurs in the
coastal and offshore waters of this biounit. Single
species fisheries include Western King Prawn, and
Abalone.
There is a large marine scalefish
industry.
Western King Prawn
This biounit is located within the waters of the
Spencer Gulf prawn fishery, which comprises 39
license holders (ie. Boats). All vessels fish within
the waters of the Spencer Gulf biounits (ie. Jussieu,
Dutton, Franklin, Yonga, Tiparra, Wardang,
Pondalowie, Spencer). In 1995/96 and 1996/97 a
total of 1,811,598 and 1,646,799 kg was caught for
this fishery, with a total effort of 27025 and 25369
hours, respectively (or 79.78% and 81.37% of the
total catch for Western King Prawn in South
Australian waters).
Page 128
SPENCER GULF REGION – TIPARRA BIOUNIT
2.2
Abalone
The Tiparra Biounit, particularly Tiparra Reef, is
the major fishing ground for Greenlip Abalone in
South Australia. In 1994/95 and 1995/96 a total of
96,324 and 117,924 kg of Greenlip was harvested
within this region (ie. MapCode 21H, 21A-G,
Moonta Bay, Tiparra Reef), and represented 67.1%
and 82.5% of the total Greenlip Central Zone catch
(or 25.57% and 31.50% of the total catch for
Greenlip in South Australian waters). In contrast,
limited amounts of Blacklip was harvested within
this region.
Aquaculture
An intertidal oyster farm operated at Bird Island for
a number of years but has since closed. A large
pond based prawn farm also operated during the
mid to late 1970s adjacent to Port Broughton.
There is an approved 10ha oyster lease in Port
Victoria Bay.
The Spencer Gulf Aquaculture Management Plan
(PIRSA 1996) recommends the following
aquaculture development in the region:
Northern Yorke Peninsula Policy Area
Marine Scalefish Fisheries
During 1995/96 and 1996/97, 42 and 41
commercial licence holders (made up of Marine
Scalefish, Restricted Marine Scalefish) caught
commercial marine scalefish species from the
Tiparra Biounit (ie. Fishing Zone 32), respectively.
License holders expended approximately 2547 and
2,272 boat days effort fishing these waters during
1995/96 and 1996/97, respectively. The marine
scalefish catch for this region (ie. Fishing Zone 32)
represented 145,970 kg in 1995/96 and 144,878 kg
in 1996/97(or 1.40% and 1.43% of the total catch
for the marine scalefish fishery in South Australian
waters).
Although license holders are not restricted to fishing
in this biounit, the following licenses are registered in
this area:
−
Port Broughton: 1 restricted marine scalefish,
15 unrestricted marine scalefish, 1 Spencer
Gulf Prawn, 2 experimental crab
−
Moonta Bay: 2 Abalone, 2 Rock Lobster, 2
abalone, 7 unrestricted marine scalefish
−
Port Hughes: 1 Abalone, 1 abalone, 3
restricted marine scalefish, 8 unrestricted
marine scalefish
−
Wallaroo: 5 restricted marine scalefish, 20
unrestricted marine scalefish, 2 Prawn
(Spencer Gulf)
−
Balgowan: 2 unrestricted marine scalefish
−
Tickera: 3 unrestricted marine scalefish
−
Chinaman
scalefish
Wells:
1
unrestricted
−
Wallaroo Zone (coastal waters, from just north
of Fisherman Bay, south to Cape Elizabeth,
excluding Offshore Tickera Management
Zone and Broughton Management Zone) –
zoned to preserve existing values and uses.
Licenses will not be considered for
aquaculture development within this zone.
Central Yorke Peninsula Policy Area
−
Hardwicke Bay Zone (waters of Hardwicke
Bay, from Cape Elizabeth to Corny Point, and
excluding the Port Victoria Management
Zone) – zoned to preserve existing uses and
values. Licenses will not be considered for
aquaculture development within this zone.
−
Port Victoria Management Zone (coastal
waters of eastern Wardang Island to Point
Pearce) – zoned to facilitate an intertidal
oyster culture industry. Licenses will be
considered for an additional 40ha of intertidal
oyster culture within this zone.
2.3
Recreation and Tourism
Fishing
−
Wallaroo and Port Hughes: boat, jetty and
rock fishing. Major species: King George
Whiting, Yellowfin Whiting, Sand Flathead,
Yelloweye Mullet, Australian Salmon,
Snapper,
Mulloway,
Snook,
Garfish,
Greenback Flounder, Blue Swimming Crab,
Tommy Rough, Trevally, Silver Drummer and
Southern Calamari.
−
There is an artificial reef near Port Broughton
(car bodies) and Wallaroo (tyre modules).
marine
Page 129
SPENCER GULF REGION – TIPARRA BIOUNIT
2.6
Tourism
Significant Cultural and Historical
Features
−
Wallaroo and Port Hughes: fishing, boating,
camping, swimming.
−
The Bamboos camping Reserve.
−
Tiparra Rocks: camping reserve.
−
SCUBA diving: Port Hughes and Wallaroo
jetties are recognised dive spots and are listed
in `Dive South Australia: The Best Dive Sites
in South Australia’ (Diving Industry
Association of South Australia). The pylons
are covered in marine life and are of great site
for underwater photography.
2.4
−
Scientific Research and Education
Fisheries research in this area includes, regular
catch and effort monitoring of the major
commercial fisheries in the region (Western
King Prawn and marine scalefish); regular
research and monitoring of larval fish stocks;
regular research and monitoring of Blacklip
and Greenlip Abalone field stocks.
Aboriginal
−
European
Shipwrecks
−
`San Miguel’ (1864-1865): a three-masted iron
barque which ran on to the Tiparra Reef near
Wallaroo.
3
CURRENT CONSERVATION STATUS
OF THE TIPARRA BIOUNIT
−
Marine Reserves
None
Marine Parks
None
−
Netting Closures
None
−
2.5
Adjacent Land Use
National and Conservation Parks
−
Bird Islands Conservation Park, north of
Warbuto Point (8 ha).
Agriculture/Industry
−
4
Most adjacent land in this biounit is used for
agriculture.
Urban Centres
−
Wallaroo (population 2,300). Wallaroo is the
economic epicentre for the copper triangle
towns.
−
Moonta (population 2,500).
−
Both centres have a permanent coastal
mooring facility for commercial and
recreational craft, as does Point Turton.
The most important areas of cultural
significance
include
the
Cape
Elizabeth/Tiparra Springs dunes and in the
dunes north of Moonta Bay. Other west coast
areas of occupation, where evidence is know
to exist, include the dunes between Port
Hughes and Cape Elizabeth and in the dunes
south of Port Victoria.
AREAS OF HIGH CONSERVATION
VALUE IN THE TIPARRA BIOUNIT
Tiparra Reef-Tiparra Bay-Cape Elizabeth
−
Prime
IUCN
Conservation
Values:
biodiversity, social, cultural values (IUCN
Category II). IUCN Identification Criteria:
naturalness (not subjected to human-induced
change), biogeographic (representative marine
habitats, geological monument-Port Hughes),
ecological (diversity of marine habitatsmangroves, seagrass meadows, reefs, nursery
and feeding areas for economic species-marine
scalefish, breeding sites for Pied Cormorants,
Crested Terns, Caspian Terns, Pacific Gulls
and Silver Gulls), economic (Greenlip Abalonemajor fishing ground in SA, marine scale
fisheries, tourism), social (aboriginal cultural
sites,
historic
shipwreck-`San
Miguel’,
recreation), scientific (abalone, marine
scalefish research and monitoring), national
(Register of the National Estate-Port Hughes),
practicality
(insulation,
accessibility,
compatibility – adjacent to Bird Islands
Conservation Park).
Page 130
SPENCER GULF REGION – TIPARRA BIOUNIT
Moonta Bay-Bird
Tiparra Bay23
−
Islands-Tiparra
Reef-
Prime
IUCN
Conservation
Values:
biodiversity, social, cultural values (IUCN
Category II). IUCN Identification Criteria:
naturalness (not subjected to human-induced
change), biogeographic (representative marine
habitats, geological monument-Port Hughes),
ecological (diversity of marine habitatsmangroves, seagrass meadows, reefs, nursery
and feeding areas for economic species-marine
scalefish, breeding sites for Pied Cormorants,
Crested Terns, Caspian Terns, Pacific Gulls
and Silver Gulls), economic (Greenlip Abalonemajor fishing ground in SA, marine scale
fisheries, tourism), social (aboriginal cultural
sites,
historic
shipwreck-`San
Miguel’,
recreation), scientific (abalone, marine
scalefish research and monitoring), national
(Register of the National Estate-Port Hughes),
practicality
(insulation,
accessibility,
compatibility – adjacent to Bird Islands
Conservation Park).
23
The reefs at Cape Elizabeth were nominated for establishment
as an Aquatic Reserve by the former South Australian Department
of Fisheries in 1974, for conservation purposes (Wynne 1980).
Page 131
SPENCER GULF REGION – WARDANG BIOUNIT
XVI
MARINE BIOGEOGRAPHY AND CONSERVATION VALUES OF THE WARDANG
BIOUNIT
This biounit extends from Island Point (near Port Victoria) on the eastern side of central Spencer Gulf to Corny
Point, on the southwestern tip of Yorke Peninsula and covers an area of 285,583ha. The biounit faces westerly
into Spencer Gulf.
mangrove trees, and shallow sand and mud flats
offshore. Goose Island lies off the north coast.
MARINE BIOGEOGRAPHY
1
OCEANOGRAPHY
3
This is a predominantly low to moderate wave
energy area, with Wardang Island also being
exposed to high wave energies. Wave energy
ranges from low near Point Turton, to moderate
from Point Souttar to Corny Point.
2
GEOLOGY
AND
GEOMORPHOLOGY24
COASTAL
The coastal geomorphology is dominated by
limestone cliffs alternating with wide dune belts.
From Cape Elizabeth to Balgowan there is a wide
dune belt followed by eroding clay cliffs. From
Balgowan to Point Pearce there is a wide dune belt
and small section of limestone cliff.
Small tidal swamps occur north of Port Victoria,
followed by small dunes and wide sandy beaches to
Point Turton, extending into a larger dune belt in
Hardwicke Bay. At Port Rickaby, the dunes are
well vegetated between The Bluff and Port Rickaby
and include a fine development of open-heath and
also an unusually large range of vegetation types
for such a narrow strip of land (7 km long and
averaging 300 metres wide).
From Point Turton to Point Souttar there are
aelonite and limestone cliffs followed by wide
dunes to Corny Point.
At Leven Beach
Conservation Park there is a unique parallel dune
formation with dense natural vegetation.
Wardang Island has a medium to high energy coast
on its west side, and a low energy coast on its
eastern, lee side. It contains the wide variety of
coastal types to be expected with the different wave
energy levels, and this makes it an invaluable
miniature of the Yorke Coast. The western coast
contains several pocket beaches separated by rocky
headlands, and there are some large sand drifts
behind these. The low lying and swampy east
coast has samphire areas and a few scattered
BIOLOGY
Major Inshore Habitats
−
Major intertidal habitats in the region include
mostly low rocky shores and sandy beaches.
−
Of the total inshore subtidal habitats mapped
in this biounit (146,919 ha), sandy bottoms
comprise 65,722 ha (44.7%), reefs comprise
54,739 ha (37.3%), and seagrass meadows
comprise 26,458 ha (18.0%).
Major Benthic Communities
•
−
Macroalgal
On
exposed
rocky
shores,
subtidal
communities (ie. west coast Wardang Island)
are dominated by a mixed-Cystophora (ie.
Cystophora
expansa,
C.monolifera,
C.monoliformis) and Sargassum community
(ie. Sargassum sonderi, S.spinuligerum,
S.heteromorphum) and the prostrate brown
alga, Lobophora variegata. On moderately
exposed coasts (ie. east coast Wardang Island,
Port Minlacowie), subtidal communities are
dominated by Scaberia agardhii, species of
Cystophora
(C.botryoides,
C.expansa),
Osmundaria prolifera, mixed-Sargassum
species
(S.linearifolium,
S.lacerifolium,
S.spinuligerum, S.heteromorphum), Cladurus
elatus and Cladostephus.
24
From Yorke Coast Protection District Study Report (Wynne
1980).
Page 132
SPENCER GULF REGION – WARDANG BIOUNIT
•
−
Seagrasses
−
Several species of protected seabirds breed on
islands of the Wardang Group, including Little
Penguins (on Goose and Green Island), Blackfaced Cormorants (on Rocky Islet, White
Rocks), Pied Cormorants, Silver Gulls and
Pacific Gulls (on Little Goose Island), Crested
Terns (on Goose, Rocky and Seal Rocks) and
Caspian Terns (on Wardang Island) (Copley
1996).
−
The intertidal reef areas at Barkers rocks
contain a wide variety of intertidal life and are
popular with educational groups.
Extensive seagrass meadows occur in
Hardwicke Bay and Port Victoria. Sandy
sediments are commonly dominated by
Posidonia sinuosa, P.angustifolia and
Amphibolis antarctica in shallower waters.
Coastal and Offshore Islands (or Reefs)
−
Wardang Island, Goose Island and Green
Island.
1.2
MARINE CONSERVATION VALUES
Physical
Geological Monuments
1
1.1
−
−
−
SIGNIFICANT
BIOLOGICAL
PHYSICAL FEATURES
AND
−
Wardang Island: volcanics, Precambrian,
Permian glacials and Cainozoic sediments.
The island is also on the Register of the
National Estate.
−
Cliff Point (Wardang Island): cliff section
unconformities.
−
Port Victoria: foreshore of Proterozoic rocks.
−
Point Turton: coastal cliffs. Features of
significance include an unconformity and
Permian glacial sediments with the type
locality for Point Turton Limestone.
Biological
White Rocks (Wardang Island and Goose
Island Conservation Park) is a haul out site for
Australian Sea Lions. Colony numbers have
fluctuated from 35 sea lions, recorded in 1978
(Robinson & Dennis (1988), to 24, recorded in
1990 (Gales 1990).
The subtidal areas of Wardang Island have
considerably large and diverse communities of
algae, seagrasses, benthic communities and
fish. The shipwrecks appear to provide refuge
for a wide variety of fish species. Wardang
Island Conservation Park is on the register of
the National Estate.
2
2.1
Goose Island Aquatic Reserve off the northern
end of Wardang Island (54 hectares) has a
submerged reef connecting it with Wardang
Island. The waters surrounding Goose Island
support dense beds of seagrasses Posidonia
and Amphibolis. The rocky areas to the west
and northwest of the island support a brown
algal community dominated by Cystophora
and Sargassum species. The islets of the
reserve can offer shelter from the wind in any
direction and this feature is reflected in the
distribution of the benthic marine organisms
around the reserve. Fishing in the reserve is
not permitted but line fishing near the reserve
can be rewarding and many species of fish are
reported to have been caught in the area
including Snook, Salmon, King George
Whiting, Garfish, Squid, Bronze Whaler
Shark, Tommy Ruff, Sweep, Trevally and
Leatherjackets.
OTHER VALUES
Commercial Fisheries
A wide variety of commercial fishing occurs in the
coastal and offshore waters of this biounit. Single
species fisheries include Western King Prawn,
Southern Rock Lobster and Greenlip Abalone.
There is also a large marine scalefish industry in
the region.
Western King Prawn
This biounit is located within the waters of the
Spencer Gulf prawn fishery, which comprises 39
license holders (ie. Boats). All vessels fish within
the waters of the Spencer Gulf biounits (ie. Jussieu,
Dutton, Franklin, Yonga, Tiparra, Wardang,
Pondalowie, Spencer). In 1995/96 and 1996/97 a
total of 1,811,598 and 1,646,799 kg was caught for
this fishery, with a total effort of 27,025 and 25,369
hours, respectively (or 79.78% and 81.37% of the
total catch for Western King Prawn in South
Australian waters).
Page 133
SPENCER GULF REGION – WARDANG BIOUNIT
Southern Rock Lobster
In 1995/96 and 1996/97 a total of 3 and 2 licensed
operators fished in the Wardang Biounit (ie.
Fishing Zone 33).
Abalone
Only Greenlip Abalone is presently commercially
harvested within this biounit. In 1994/95 and
1995/96 a total of 34,719 and 7,059 kg of Greenlip
was harvested within this region (ie. MapCode
22A, 24A, Port Victoria, Hardwicke Bay region),
and represented 24.2% and 4.9% of the total
Greenlip Central Zone catch (or 9.22% and 1.89%
of the total catch for Greenlip in South Australian
waters).
2.2
At present 3 intertidal Pacific oyster leases have
been approved in the Port Victoria - Wardang
Island area. One onshore abalone farm has also
been approved in this region and others may well
follow given the suitability of large areas of land
adjacent to the coast.
The Spencer Gulf Aquaculture Management Plan
(PIRSA 1996) recommends the following
aquaculture development in the region:
Central Yorke Peninsula Policy Area
−
Port Victoria Management Zone (coastal
waters of eastern Wardang Island to Point
Pearce) – zoned to facilitate an intertidal
oyster culture industry. Licenses will be
considered for an additional 40ha of intertidal
oyster culture within this zone.
−
Hardwicke Bay Zone (waters of Hardwicke
Bay, from Cape Elizabeth to Corny Point, and
excluding the Port Victoria Management
Zone) – zoned to preserve existing uses and
values. Licenses will not be considered for
aquaculture development within this zone.
Marine Scalefish Fisheries
During 1995/96 and 1996/97, 88 and 74
commercial licence holders (made up of Marine
Scalefish, Restricted Marine Scalefish categories)
caught commercial marine scalefish species from
the Wardang Biounit (ie. Fishing Zone 33),
respectively.
License holders expended
approximately 4,024 and 3,660 boat days effort
fishing these waters during 1995/96 and 1996/97,
respectively. The marine scalefish catch for this
region (ie. Fishing Zone 33) represented 172,023
kg in 1995/96 and 218,560 kg in 1996/97(or 1.65%
and 2.16% of the total catch for the marine
scalefish fishery in South Australian waters).
Although license holders are not restricted to fishing
in this biounit, the following licenses are registered in
this area:
−
Point Turton: 1 Abalone, 2 Rock Lobster 1
abalone, 1 restricted marine scalefish, 9
unrestricted marine scalefish
−
Port Victoria: 1 Rock Lobster, 6 restricted
marine scalefish, 13 unrestricted marine
scalefish
−
Hardwicke Bay: 1 restricted marine scalefish,
6 unrestricted marine scalefish
−
Port Minlacowie: 4 restricted marine scalefish
3 unrestricted marine scalefish
−
Aquaculture
2.3
Recreation and Tourism
Fishing
−
Port Victoria and Wardang Island: boat, jetty
and shore fishing.
Major species: King
George Whiting, Sand Flathead, Yelloweye
Mullet, Australian Salmon, Snapper, Snook,
Garfish, Blue Swimming Crab, Tommy
Rough, Trevally, Toothbrush Leatherjacket,
Silver Drummer and Southern Calamari.
−
Hardwicke Bay, Point Turton and Point
Souttar: boat and jetty (Point Turton) fishing.
Major species: King George Whiting, Sand
Flathead, Yelloweye Mullet, Snapper, Snook,
Garfish, Tommy Rough and Southern
Calamari.
Tourism
Port Rickaby: 2 unrestricted marine scalefish,
3 restricted marine scalefish
−
Port Victoria and Wardang Island: fishing,
boating, camping, historic area, including
shipwrecks (underwater trail on Wardang
island), and SCUBA diving and snorkelling
off Wardang Island. Charter boats operate to
Wardang Island.
Page 134
SPENCER GULF REGION – WARDANG BIOUNIT
−
Port Rickaby: fishing, boating, camping.
−
Bluff Beach and Parsons Beach: fishing,
boating, camping.
−
Hardwicke Bay, Point Turton, Point Souttar:
fishing, boating, swimming, camping.
−
2.4
−
−
SCUBA diving: Wardand Island and Point
Turton jetty are recognised dive spots and are
listed in `Dive South Australia: The Best Dive
Sites in South Australia’ (Diving Industry
Association of South Australia). Wardang
Island is recognised for wreck diving and has
nine shipwrecks around the island, eight of
which form the Wardang Island Maritime
Heritage Trail (see below). White Rocks at
the northern end of Wardang Island is a
popular site for diving with sea lions. Point
Turton jetty, like Port Hughes and Wallaroo
jetties, contains abundant marine life and is
popular and accessible spot for underwater
photography.
Scientific Research and Education
Wardang Island is used extensively for
educational purposes by various schools,
institutions and clubs. In particular, Goose
Island Conservation Park and Aquatic
Reserve, off Wardang Island's north coast, is
used on a regular basis by Scotch College as
an educational field station. The College has
an annual licence to use the island and is
required to conserve the flora and fauna. The
surrounding waters were proclaimed an
Aquatic Reserve at the school's request. The
park also includes White Rocks Island.
2.5
National and Conservation Parks
−
Goose Island Conservation Park (20 ha) and
Aquatic Reserve (54 ha).
−
Leven Beach Conservation Park (494 ha).
Agriculture/Industry
−
A beach and wave cut platform at Barker
Rocks, south of Port Rickaby, is regularly
used by educational and school groups.
−
Fisheries research in this area includes, regular
catch and effort monitoring of the major
commercial fisheries in the region (Western
King Prawn and marine scalefish); regular
research and monitoring of larval fish stocks;
regular research and monitoring of Blacklip
and Greenlip Abalone field stocks.
Most adjacent land in this biounit is used for
agriculture.
Urban Centres
−
Port Victoria (population 250).
−
This centre has a permanent coastal mooring
facility for commercial and recreational craft,
as does Point Turton.
2.6
Features
Significant Cultural and Historical
Aboriginal
−
Wardang Island is owned by the Aboriginal
Lands Trust and is leased to the Point Pearce
Community Council.
The council has
considered a sub-lease to the Minister of
Education, and the Department of Further
Education has established an outdoor
education based camp on the island.
−
The most important areas of cultural
significance
include
the
Cape
Elizabeth/Tiparra Springs dunes and in the
dunes north of Moonta Bay. Other west coast
areas of occupation, where evidence is know
to exist, include the dunes between Port
Hughes and Cape Elizabeth and in the dunes
south of Port Victoria.
The waters surrounding Wardang Island
comprise one of the most significant areas of
maritime heritage in South Australia. The
wrecks along the recently established
underwater heritage trail are both significant
educational site as well as sites for ongoing
maritime research.
−
Adjacent Land Use
European
−
Port Victoria is the last of the windjammer
ports.
Page 135
SPENCER GULF REGION – WARDANG BIOUNIT
Shipwrecks
−
The Wardang Island Maritime Heritage Trail
consists of 8 shipwrecks (with underwater
interpretative plaques):
−
`Songvaar’ (1884-1912): a three-masted iron
ship whose own anchor pierced its hull.
−
`Moorara’ (1909-1975): a three-masted
schooner which sank during a "blow" while at
anchorage off the island.
−
`S.S. Australian’ (1879-1912): a schoonerrigged iron screw steamer which struck the
south-eastern corner of the island.
−
`MacIntyre’ (1877-1927): a three-masted iron
schooner which struck a rock off the southern
end of the island.
−
`Monarch’ (1871-1909): a three-masted
wooden schooner which struck rocks on the
southern end of the island.
−
`Notre Dame D'Arvor’ (1902-1920): a threemasted steel barque which grounded on rocks
on the south-western corner of the island.
`S.S. Investigator’ (1882-1918): a schoonerrigged iron screw steamer, which grounded on
rocks to the south-west of the island.
−
`Aagot’ (1882-1907): a three-masted iron
barque which ran aground on rocks on the
western side of the island.
3
CURRENT CONSERVATION STATUS
OF THE WARDANG BIOUNIT
−
Marine Reserves
Goose Island (54 ha).
−
Marine Parks
None.
AREAS OF HIGH CONSERVATION
VALUE IN THE WARDANG BIOUNIT
Wardang Island- Port Victoria
−
−
−
4
Prime IUCN Conservation Values: education,
biodiversity, social, cultural values (IUCN
Category II). IUCN Identification Criteria:
naturalness (not subjected to human-induced
change), biogeographic (representative marine
habitats, geological monuments-Wardang
Island, Cliff Point, Port Victoria), ecological
(diversity of marine habitats, seagrass
meadows, reefs, nursery and feeding areas for
economic species – marine scalefish, haul out
site for Australian Sea Lions, breeding areas for
Little Penguins, Black-faced Cormorants, Pied
Cormorants, Silver Gulls, Pacific Gulls, Crested
Terns and Caspian Terns, Australian Sea
Lions), economic (Greenlip Abalone, marine
scale fisheries, tourism), social (shipwrecks –
Maritime Heritage Trail, recreation, educationGoose Island field station), scientific (marine
scalefish research and monitoring), national
(Register of the National Estate), practicality
(insulation, compatibility-adjacent to Wardang
Island Conservation Park, accessibility).
Point Turton-Leven Beach
−
Prime IUCN Conservation Values: social
values, biodiversity (IUCN Category III). IUCN
Identification Criteria: naturalness (not
subjected
to
human-induced
change),
biogeographic (representative marine habitats,
geological monument-Point Turton), ecological
(nursery and feeding areas for economic
species-marine scalefish), economic (prawn,
marine scale fisheries, tourism), social
(recreation), scientific (prawn, marine scalefish
research
and
monitoring),
practicality
(insulation, compatibility -Leven Beach
Conservation Park, accessibility).
Netting Closures
Port Victoria (in those waters that exceed 5 m
in depth contained within a line from Point
Gawler to the north west point on Goose
Island, then to Reef Point).
Page 136
SPENCER GULF REGION – PONDALOWIE BIOUNIT
XVII
MARINE BIOGEOGRAPHY AND CONSERVATION VALUES OF THE
PONDALOWIE BIOUNIT
This biounit extends from Corny Point to West Point (on the southwestern tip of Yorke Peninsula) and covers an
area of 22,130 ha. The biounit faces west into lower Spencer Gulf.
MARINE BIOGEOGRAPHY
1
−
OCEANOGRAPHY
Wave energy range is high from Corny Point to
Cape Spencer.
2
GEOLOGY
AND
GEOMORPHOLOGY 25
COASTAL
The coastal geomorphology is dominated by
limestone cliffs alternating with wide dune belts.
Corny Point is an area of aelonite and limestone
cliffs. From Daly Head to Formby Bay there is a
wide dune belt and limestone cliff slopes.
Dunes located between Daly Head and Little
Lizard Bay are by far the most extensive parabolic
dunes in the region. The seaward portion consists
of unvegetated mobile sand in the form of a sheet
drift approximately 7km long by 1km wide. This
partly overlies and is backed by an almost equal
area of stable vegetated parabolic dunes containing
a diverse flora.
Brown's Beach and Pondalowie Bay are also areas
with wide dune belts.
At Cape Spencer there are aelonite and limestone
cliffs, followed by a wide dune belt at Marion Bay.
3
BIOLOGY
Major Inshore Habitats
−
Of the total inshore subtidal habitats mapped
in this biounit (179,964 ha), sandy bottoms
comprise 15,077 ha (83.9%), reefs comprise 2
862 ha (15.9%), and seagrass meadows
comprise 25 ha (0.1%).
Major Benthic Communities
•
Macroalgal
−
On exposed rocky shores (eg. Berry Bay,
Formby Bay), subtidal communities are
dominated by Ecklonia radiata, Scytothalia
dorycarpa and a understorey of red algae
(Plocamium, Peysonnelia, Phacelocarpus)
and crustose corallines. On less exposed
shores (eg Daly Head), the deeper subtidal
communities are dominated by Carpoglossum
confluens,
Homeostrichus
sinclairii,
Cystophora grevillea, C.platylobium and
mixed reds (Phacelocarpus, Cladurus elatus,
Gracilaria). In shallower areas, reefs are
dominated by Ecklonia radiata, Acrocarpia
paniculata, Cystophora monoliformis and
mixed coralline algae (Lithothamnion,
Haliptilon, Metagoniolithon, Cheilosporum,
Jania). In sheltered areas (eg. Royston Head)
reefs are dominated by species of Cystophora
(C.monilifera, C. moniliformis), Ecklonia
radiata, Caulerpa cactoides, Scytothalia
dorycarpa, and Sargassum verruculosum in
shallow areas. In deep areas, reefs are
dominated by species of Sargassum (S.fallax,
S.sonderi, S.linearifolium), Ecklonia radiata,
and mixed fucoids (Cystophora moniliformis,
Myriodesma
integrifolium,
Micropeuce,
Areschougia).
Major intertidal habitats in the region include
mostly exposed rocky shores and sandy
beaches.
25
From Yorke Coast Protection District Study Report (Wynne
1980).
Page 137
SPENCER GULF REGION – PONDALOWIE BIOUNIT
•
−
1.2
Seagrass
Seagrass meadows occur in Formby Bay and
West Bay. Sandy sediments (ie. Dunn Point,
West Bay) dominated by Amphibolis
antarctica (to 13m) and Posidonia sinuosa,
and also, Heterozostera tasmanica, Halophila
australis and the green alga, Caulerpa
scapelliformis.
Physical
Geological Monuments
−
Corny
Point:
unconformity
sediments.
−
Browns Beach: Proterozoic basement rocks.
Proterozoic
underlying
basement
Cainozoic
Coastal and Offshore Islands (or Reefs)
−
2
Daly Head Island, Pondalowie Islands
(Royston, Middle Islands - part of Innes
National Park).
MARINE CONSERVATION VALUES
1
1.1
SIGNIFICANT
BIOLOGICAL
PHYSICAL FEATURES
AND
Biological
−
The intertidal reef areas at Gleesons Landing
near Daly Head contains a wide variety of
intertidal life.
−
Innes National Park preserves the largest area
of natural bushland remaining on the Yorke
Peninsula, and preserves the habitat of the
Western Whipbird. It is characterised by a
sandy undulating plain with dunes and salt
lakes, or low cliffs along the coastline. The
magnificent and spectacular coastal scenery is
one of the major attractions of this park, which
includes cliffs, wave cut platforms, rocky
headlands and sandy beaches. Typical coastal
dune and cliff-top vegetation is backed by
mallee and teatree scrub. It is still possible to
see the remains of the shipwreck `Ethel' near
Reef Head. Daly Head, Royston, Middle
Islands are included in the national park.
Little Penguins and Silver Gulls breed on
Royston and Middle Islands (Pondalowie Bay)
(Copley 1996).
2.1
OTHER VALUES
Commercial Fisheries
A wide variety of commercial fishing occurs in the
coastal and offshore waters of this biounit. Single
species fisheries include Western King Prawn,
Southern Rock Lobster and Abalone. There is also
a significant marine scalefish industry within this
region.
Western King Prawn
This biounit is located within the waters of the
Spencer Gulf prawn fishery, which comprises 39
license holders (ie. Boats). All vessels fish within
the waters of the Spencer Gulf biounits (ie. Jussieu,
Dutton, Franklin, Yonga, Tiparra, Wardang,
Pondalowie, Spencer). In 1995/96 and 1996/97 a
total of 1,811,598 and 1,646,799 kg was caught for
this fishery, with a total effort of 27,025 and 25,369
hours, respectively (or 79.78% and 81.37% of the
total catch for Western King Prawn in South
Australian waters).
Southern Rock Lobster
In 1995/96 and 1996/97 a total of 19 and 19
licensed operators fished in the south western and
southern Yorke Peninsula (and Investigator Strait)
region (ie. Fishing Zone 40), catching
approximately 71,795 and 64,785 kg of lobsters,
respectively (or 1.40% and 1.27% of the total catch
for Southern Rock Lobster in South Australian
waters).
Page 138
SPENCER GULF REGION – PONDALOWIE BIOUNIT
Abalone
Warooka Policy Area
Blacklip Abalone and some Greenlip Abalone is
presently commercially harvested within this
biounit (ie. MapCode 23A-D, Corny Point to Foul
Bay region). In 1994/95 and 1995/96 a total of
4,656 and 3,504 kg of Blacklip was harvested
within this region, and represented 11.8% and 8.3%
of the total Blacklip Central Zone catch (or 0.94%
and 0.76% of the total catch for Blacklip in South
Australian waters). Greenlip Abalone figures are
unavailable due to confidentiality constraints.
−
2.3
−
Corny Point and Berry Bay: boat, beach and
rock fishing. Major species: King George
Whiting, Sand Flathead, Yelloweye Mullet,
Australian Salmon, Snapper, Mulloway,
Snook, Garfish, Tommy Rough, Trevally,
Toothbrush, Leatherjacket, Silver Drummer
and Southern Calamari.
−
Daly Head: beach and rock fishing. Major
species: King George Whiting, Sand Flathead,
Yelloweye Mullet, Australian Salmon,
Mulloway, Sweep, Tommy Rough. Trevally,
Toothbrush Leatherjacket, Silver Drummer
and Southern Calamari.
−
Browns Beach: beach fishing. Major species:
Black Bream, Yelloweye Mullet, Australian
Salmon and Tommy Rough.
−
Pondalowie Bay: boat, rock and beach fishing.
Major species: King George Whiting, Sand
Flathead, Yelloweye Mullet, Australian
Salmon, Snapper, Snook, Garfish, Southern
Rock Lobster, Tommy Rough, Trevally,
Toothbrush Leatherjacket, Silver Drummer
and Southern Calamari.
−
West Cape: beach and rock fishing. Major
species: Sand Flathead, Yelloweye Mullet,
Australian Salmon, Sweep, Tommy Rough
and Toothbrush Leatherjacket.
−
Cape Spencer: beach and rock fishing. Major
species: Sand Flathead, Yelloweye Mullet,
Australian Salmon, Sweep, Garfish, Tommy
Rough, Toothbrush Leatherjacket and Silver
Drummer.
Although license holders are not restricted to fishing
in this biounit, the following licenses are registered in
this area:
−
Pondalowie: 2 Rock Lobster
−
Corny Point: 3 Rock Lobster, 11 unrestricted
marine scalefish
2.2
Aquaculture
There is currently no aquaculture development
within this region. The coastline south of Corny
Point is exposed to waves and swell, and is boarded
by high cliffs, extensive dunal systems and/or
National Park.
Because of this aquaculture
development is unlikely through most of this
region.
The Spencer Gulf Aquaculture
Management Plan (PIRSA 1996) recommends no
aquaculture development within the region:
Recreation and Tourism
Fishing
Marine Scalefish Fisheries
During 1995/96 and 1996/97, 54 and 51
commercial licence holders (made up of Marine
Scalefish, Restricted Marine Scalefish licence
categories) caught commercial marine scalefish
species from the in the south western and southern
Yorke Peninsula (and Investigator Strait) region
(ie. Fishing Zone 40), respectively.
License
holders expended approximately 1,742 and 1,668
boat days effort fishing these waters during
1995/96 and 1996/97, respectively. The marine
scalefish catch for this region (ie. Fishing Zone 40)
represented 200,171 kg in 1995/96 and 211,150 kg
in 1996/97(or 1.93% and 2.08% of the total catch
for the marine scalefish fishery in South Australian
waters).
Warooka Zone (coastal waters, within 3nm of
the coast, from Corny Point to Cape Spencer)
– zoned to preserve existing values (ie.
conservation) and uses (ie. fisheries,
recreation, tourism). Licenses will not be
considered for aquaculture development
within this zone.
Page 139
SPENCER GULF REGION – PONDALOWIE BIOUNIT
Tourism
Agriculture/Industry
−
Corny Point: spectacular coastal scenery and a
historic lighthouse.
−
Innes National Park: popular camping area,
spectacular coastal scenery and SCUBA
diving. Large Blue Gropers and Southern
Rock Lobster are particular attractions for
SCUBA divers. The small holiday and fishing
village of Pondalowie Bay, and South Island
are popular camping sites and are excluded
from the national park.
−
Browns Beach: camping area, fishing.
−
Pondalowie
fishing.
−
SCUBA diving: Corny Point, Browns Beach,
Pondalowie Bay, are all recognised reefs dives
and are listed in `Dive South Australia: The
Best Dive Sites in South Australia’ (Diving
Industry Association of South Australia).
Most of these dives are recommended for
experienced divers only.
2.4
−
−
2.5
Bay:
camping
and
−
Most of the adjacent land in this biounit is
predominantly agricultural.
Urban Centres
−
There are no major urban centres, although
there are a number of areas with holiday shack
development.
2.6
Values
Significant Cultural and Historical
Aboriginal
surfing,
−
European
−
The coast from Gleesons Landing to Daly
Head has an extensive intertidal and shallow
sublittoral platform which is used by schools
for teaching purposes. This area was proposed
as an educational reserve by the Department
of Fisheries in 1974. 26
−
`Ethel’: an iron barque of 700 tons that went
ashore in January 1904 near Reef Head.
Retrieval attempts were unsuccessful, and
today one of her boilers can still be seen
protruding out of the sand near Reef Head.
3
CURRENT CONSERVATION STATUS
OF THE PONDALOWIE BIOUNIT
−
Marine Reserves
None
−
Marine Parks
None
−
Adjacent Land Use
National and Conservation Parks
Innes National Park (9,232 ha): includes Royston,
Middle and Chinamans Hat islands.
Lighthouse at Corny Point.
Shipwrecks
Scientific Research and Education
Fisheries research in this area includes, regular
catch and effort monitoring of the major
commercial fisheries in the region (Western
King Prawn, Abalone and marine scalefish);
regular research and monitoring of larval fish
stocks; regular research and monitoring of
Blacklip and Greenlip Abalone field stocks.
Not known.
−
Netting Closures
Brown's Beach (all waters adjacent to Brown's
Beach within 1/4 mile of high water mark).
Pondalowie Bay (waters contained within a
line from Roysten Head through the North,
Middle and South Islets to southern shore of
Pondalowie Bay).
26
From Yorke Coast Protection District Study Report (Wynne
1980).
Page 140
SPENCER GULF REGION – PONDALOWIE BIOUNIT
4
AREAS OF HIGH CONSERVATION
VALUE
IN
THE
PONDALOWIE
BIOUNIT
Corny Point
−
Prime IUCN Conservation Values: social
values, biodiversity, cultural values (IUCN
Category III). IUCN Identification Criteria:
naturalness (not subjected to human-induced
change), biogeographic (representative marine
habitats, geological monuments-Corny Point),
ecological (range of marine habitats, seagrass
meadows, reef), economic (abalone, rock
lobster, marine scale fisheries, tourism), social
(shipwrecks, recreation, diving, Corny Point
lighthouse), scientific (abalone, rock lobster,
marine scalefish research and monitoring),
national (potential for Register of the National
Estate), practicality (insulation, accessibility,
compatibility-adjacent to lighthouse reserve).
Formby Bay-Innes National Park27
−
Prime
IUCN
Conservation
Values:
biodiversity, education, social, cultural values
(IUCN Category II). IUCN Identification
Criteria: naturalness (not subjected to humaninduced change), biogeographic (representative
marine habitats, geological monuments-Browns
Beach), ecological (diversity of marine habitats,
high marine biodiversity, reef fish populations Blue Groper, breeding populations-Little
Penguins, Silver Gulls, seabirds-Black-faced
Cormorants, Pied Cormorant, Reef Heron, Pied
Oyster Catcher, Sooty Oyster Catcher, Grey
Plover, Hooded Dotterel, Red Neck Stint, Black
Winged Stint, Pacific Gull, Caspian Tern,
Crested Tern, Silver Gull, Shy Albatross, Little
Pied Cormorant, Banded Plover, Banded Stilt,
Little Tern), economic (tourism, Greenlip
Abalone, Southern Rock Lobster, marine
scalefish fisheries), social (`Ethel' shipwreck,
recreation,
diving,
education-Gleesons
Landing-Daly Head), national significance
(potential for listing on Register of National
Estate), practicality (insulation, accessibility,
compatibility-adjacent to Innes National Park).
27
Gleesons Landing to Daly Head was nominated for
establishment as an Aquatic Reserve by the former South
Australian Department of Fisheries in 1974, for educational
purposes (Wynne 1980).
Page 141
SPENCER GULF REGION – GAMBIER BIOUNIT
XVIII MARINE BIOGEOGRAPHY AND CONSERVATION VALUES OF THE
GAMBIER BIOUNIT
This biounit comprises the Gambier Isles and Neptune Islands.
MARINE BIOGEOGRAPHY
1
OCEANOGRAPHY
This region forms the southwestern arm of Spencer
Gulf and has an overall easterly orientation.
Consequently, it is a zone of low wave energy with
prevailing offshore winds.
2
GEOLOGY
AND
GEOMORPHOLOGY
COASTAL
The Gambier Islands include Wedge Island, North
Island and several rocky islets and reefs. All are
crystalline basement. Wedge Island has a thick
"wedge shaped" cover of calcareous aeolianite. The
outcrop of crystalline basement is continuous except
along the east coast where beach sands have been
deposited. Young beach sands have been blown
inland on all but the eastern side of the island, and are
now covered by sparse vegetation. In the northern
portion of the island small lakes occur separated from
the ocean by older coastal dunes. North Island has
only a thin cover of aeolianite which is substantially
covered by recent sand dunes.
3
•
The moderate-water areas of North Island are
dominated mainly by mixed Cystophora species,
such as C. moniliformis, C. siliquosa and C.
retorta, in the shallows (5m), whilst seagrass
species dominate deeper sites (see below).
•
−
Seagrass species are not dominant at most
depths around Wedge Island, although
Posidonia and Heterozostera species are
common at 10m. Posidonia is dominant at
10-15m around North Island.
−
Gambier Islands (North Island, South West
Rocks and Peaked Rocks and Wedge Island).
−
Neptune Islands (South Neptunes, North
Neptunes).
Rocky shore, sandy beaches, intertidal sand
flats, subtidal rocky reefs and boulders,
seagrass meadows and algae assemblages.
MARINE CONSERVATION VALUES
Major Benthic Communities
1
Macroalgal
1.1
−
Seagrasses
Coastal and Offshore Islands (or Reefs)
BIOLOGY
Major Inshore Habitats
−
Sheltered shallow-water (5m) areas around Wedge
are dominated by the Cystophora species C.
subfarcinata and C. moniliformis, and Sargassum
species S. fallax and S. spinuligerum. Xiphophora
and Osmundaria are also found here, as are various
Caulerpa species. Ecklonia and mixed Cystophora
(C. siliquosa, C. retorta) and Sargassum (S. fallax,
S. verruculosum) species are the algal dominants of
waters 10 to 15m deep.
Areas of moderate water movement around
Wedge Island are dominated by Ecklonia,
Scytothalia, Seirococcus and Sargassum fallax
at 10 to 20m. Small brown algal species such
as Homeostrichus and Chlanidophora are also
common. Red algal dominants include
Phacelocarpus and Plocamium species.
−
SIGNIFICANT
BIOLOGICAL
PHYSICAL FEATURES
AND
Biological
Neptune Islands Conservation Park. The park
consists of all islands in the North and South
Neptunes with the exception of the southernmost island, which is one of South Australia's
last few manned Lighthouse Reserves. The
Neptune Islands are of national significance,
containing the largest breeding colonies of
Page 142
SPENCER GULF REGION – GAMBIER BIOUNIT
New Zealand Fur Seal (Arctocephalus
forsteri) in South Australia (and Australia).
Together, colonies on the Neptune Islands
have been recently estimated at almost 16 800
individuals, or 61% of the total SA population
(27,616) or 49% of the Australian population
(34,700) (Shaughnessy et al. 1994). Breeding
colonies of fur seals have been recorded on
South Neptune (1,974 pups, estimated
population 9,673) and North Neptune (1,472
pups, estimated population 7,212). Haul out
and basking sites have been recorded on South
Neptune Island (South), Low Rocks
(Shaughnessy et al. 1994).
−
−
Colonies of the rare Australian Sea Lions
(Neophoca cinerea) have also been recorded
on the Neptune Islands. Breeding colonies
occur on South Neptune Island (North) (4
pups, estimated population 19), while
breeding possibly occurs on Rocky Island
(North and South), East Neptune Islands
(Gales 1990). Haul out and basking sites in
this region include Low Rocks, West Neptune
and North and South Neptune Islands (Watts
& Ling 1985, Gales et al. 1994).
More recently, the Neptune Islands is
becoming well-known, both nationally and
internationally as one of the major sites in the
world for research and filming of White
Sharks (Carcharodon carcharias).
Grasslands on the islands support 2-4 breeding
pairs of Cape Barren Geese annually in the
winter months (Robinson et al. 1982) while the
whole island supports dense populations of the
Southern Bush Rat (Rattus fuscipes). The
islands also have significant breeding colonies
of seabirds. The `vulnerable' Fairy Terns
breeds on South Neptune Island and the Islet
of North Neptunes; Crested Terns breed on
Lighthouse Island, South Neptune; and
Caspian Terns breed on South Neptune Islands
(Copley 1996).
−
Gambier Islands Conservation Park. North
Island and Peaked Rock are known breeding
sites for rare Australian Sea Lions, while
South West Rock is possibly a haul out site
only (Gales 1990). New Zealand Fur Seals
have been recorded on Wedge Island, Peaked
Rock (West), North Island and South West
Rock (Shaughnessy 1990). However these
sites are not known breeding areas. The open
habitat of North Island supports an extremely
large population of Southern Bush Rats and
these formed part of a recent genetic analysis
of island populations of these species (Schmitt
1978; Schmitt & White 1979).
−
Breeding colonies of Little Penguins, Whitefaced Storm Petrels, common on Wedge
Island (Copley 1996).
1.2
−
2
Physical
None.
OTHER VALUES
2.1
Commercial Fisheries
Southern Rock Lobster
The offshore islands in this region (Gambier
Islands, Neptune Islands, and Thistle Island), and
also, north western Kangaroo Island, represent a
major region for lobster production in South
Australia. In 1995/96 and 1996/97, a total of 51
and 47 licensed operators fished in the area (ie.
Fishing Zone 39), catching approximately 108,867
and 136,826 kg of lobsters, respectively (or 2.13%
and 2.68% of the total catch for Southern Rock
Lobster in South Australian waters).
Abalone
Within this region, Greenlip and Blacklip Abalone
is harvested at the Neptune Islands and the
Gambier Isles. In 1994/95 a total of 7,317 kg of
Greenlip was harvested around the Neptune Islands
(ie. MapCode 17C), and represented 3.2% of the
total Greenlip Western Zone catch (or 1.94% of the
total catch for Greenlip in South Australian
waters). Blacklip Abalone figures are unavailable
due to confidentiality constraints. In the Gambier
Isles (ie. MapCode 19F), a total of 7,230 and 6,312
kg was harvested during 1994/95 and 1995/96,
which represented 3.2% and 2.8% of the total
Greenlip Western Zone catch (or 1.92% and 1.69%
of the total catch for Greenlip in South Australian
waters). Blacklip Abalone figures are unavailable
due to confidentiality constraints
Marine Scalefish Fisheries
Fishing is limited within the Gambier Islands,
Neptune Islands, and Thistle Island (and also, along
the north western coast of the Kangaroo Island) (ie.
Fishing Zone 39). In 1995/96 and 1996/97, a total
of 21 and 31 licensed operators fished in the area
(ie. Fishing Zone 39), catching a total of 66,188
and 86,753 kg, respectively (or 0.64% and 0.86%
of the total catch for the marine scalefish fishery in
South Australian waters).
Page 143
SPENCER GULF REGION – GAMBIER BIOUNIT
2.2
Aquaculture
Within the Gambier Region, the remoteness of this
region and its general exposure to waves and swell
suggest that aquaculture development is unlikely,
even in the lee of islands.
Within the offshore Spencer Gulf region, aquaculture
development is unlikely in the near future. While sea
cages have now been developed which can withstand
the physical forces that might arise in this region
during storm conditions, their costs are exceedingly
high. This cost factor, the need for automating feed
delivery so as to reduce shore based servicing
frequency, the present availability of nearer shore
sites, and the preliminary nature of finfish culture in
South Australia, all suggest that aquaculture
development within this region is unlikely in the near
future.
2.3
−
−
2.4
−
−
Recreation and Tourism
Researchers from the SANPWS regularly
conduct surveys of Australian Sea Lion and
New Zealand Fur Seal colonies on the islands.
Offshore islands: the following areas are
popular for SCUBA diving and recreational
fishing (including Abalone and Southern Rock
Lobster) - Hopkins and Thistle Islands, West
Bay, Gambier Islands (Wedge Island), Sir
Joseph Banks Group of Islands, and the
Althorpe Islands. Access to these islands is
through charter companies such as Failie
Charters, as well as by private vessels.
2.5
National and Conservation Parks
−
Gambier Islands Conservation Park (64 ha):
comprises three islands and islets of the
Gambier Group, North Island, SW Rocks and
Peaked Rocks. Wedge Island, the main island
of the Gambier Group is held in freehold title
and is run as a tourist resort.
−
Neptune Islands Conservation Park (318 ha):
includes all islands in the North and South
Neptunes with the exception of the southernmost island which is one of South Australia's
last few manned Lighthouse Reserves.
−
Agriculture/Industry
None.
−
Urban Centres
None.
2.6
Features
−
Other research in this area includes, regular
catch and effort monitoring of the major
commercial fisheries in the region (Western
King Prawn and marine scalefish); regular
research and monitoring of larval fish stocks;
regular research and monitoring of Blacklip
and Greenlip Abalone field stocks.
Significant Cultural and Historical
Aboriginal
Not known.
European
Shipwrecks
−
`Glenpark' (1897-1901): a Historic Relic
declared under the South Australian Historic
Shipwrecks Act 1981 (the only one in South
Australia). The vessel, a three-masted steel
ship, ran ashore on a rock off Wedge Island.
3
CURRENT CONSERVATION STATUS
OF THE GAMBIER BIOUNIT
Scientific Research and Education
Gambier Islands Conservation Park: the open
habitat of North Island supports an extremely
large population of Southern Bush Rats and
these formed part of a genetic analysis of
island populations of these species (Schmitt
1978; Schmitt & White 1979).
Adjacent Land Use
−
Marine Reserves
None
−
Marine Parks
None
−
Netting Closures
Wedge Island (all waters between Wedge
Island and North Islet contained by two lines;
one from the western point of Wedge Island to
the western point of North Islet and the other
from the eastern tips of both islands).
Page 144
SPENCER GULF REGION – GAMBIER BIOUNIT
4
AREAS OF HIGH CONSERVATION
VALUE IN THE GAMBIER BIOUNIT
Gambier Isles
−
Prime IUCN Conservation Values: rare and
endangered species/habitats, biodiversity (IUCN
Category IA). IUCN Identification Criteria:
naturalness (not subjected to human-induced
change), biogeographic (representative habitats,
unique geology), ecological (range of habitats,
nursery areas, breeding areas for rare
Australian Sea Lions, haul out sites for New
Zealand Fur Seals, breeding colonies of Little
Penguins,
White-faced
Storm
Petrels),
economic (abalone, rock lobster, marine scale
fisheries, dive tourism and fishing charters),
social
(historic
shipwrecks-`Glenpark’,
recreation, education), scientific (marine
mammals, abalone, rock lobster research and
monitoring), national (potential for Register of
the National Estate), practicality (insulation,
compatibility-adjacent to Gambier Isles
Conservation Park).
Neptune Isles
−
Prime IUCN Conservation Values: rare and
endangered species/habitats, biodiversity (IUCN
Category IA). IUCN Identification Criteria:
naturalness(not subjected to human-induced
change), biogeographic (representative habitats,
largest breeding colonies of New Zealand Fur
Seals in Australia, unique geology), ecological
(range of habitats, nursery areas, breeding
areas for New Zealand Fur Seals, haul out sites
for Australian Sea Lions, breeding sites for
seabirds-`vulnerable' Fairy Terns, Crested
Terns, Caspian Terns, White Shark populations,
roosting sites for Cape Barren Geese, Southern
Bush Rat), economic (Blacklip Abalone,
Southern Rock Lobster, marine scale fisheries,
tourism),
social
(education),
scientific
(monitoring and research sites for New Zealand
Fur Seals, White Shark populations, abalone,
rock lobster research and monitoring), national
(Register of the National Estate, national
importance of breeding colonies of New
Zealand Fur Seals), practicality (insulation,
compatibility-adjacent to Neptune Islands
Conservation Park).
Page 145
GULF OF ST VINCENT – FLEURIEU PENINSULA REGION
MARINE BIOGEOGRAPHY AND CONSERVATION VALUES OF GULF ST
VINCENT - FLEURIEU PENINSULA REGION
MARINE BIOGEOGRAPHY
1
2.
3.
4.
5.
Gulf St Vincent – Fleurieu Peninsula
Oceanography
Climate
Coastal Geomorphology and Landforms
Biology
MARINE CONSERVATION VALUES
1.
2.
3.
Significant Biological and Physical Features
Significant Cultural or Historical Features
Current Conservation Status of Gulf St Vincent
BIOUNITS
1.
2.
3.
4.
5.
6.
Sturt
Investigator
Orontes
Clinton
Yankalilla
Encounter
Page 146
GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – STURT AND INVESTIGATOR BIOUNITS
MARINE BIOGEOGRAPHY AND CONSERVATION VALUES OF GULF ST
VINCENT - FLEURIEU PENINSULA REGION
MARINE BIOGEOGRAPHY
1 GULF ST VINCENT – FLEURIEU
PENINSULA
Gulf St Vincent falls within the coastal
geomorphological region known as the Gulfs
Province (Short et al. 1986). This region extends
from Cape Catastrophe, on the south eastern tip of
Eyre Peninsula, to Rapid Head on the Fleurieu
Peninsula, and includes South Australia's other
large sheltered gulf ecosystem; Gulf St Vincent.
Within these sheltered gulf waters occur some of
the largest temperate seagrass ecosystems in the
world. The sheltered waters also provide an ideal
habitat for extensive, intertidal forests of the Grey
Mangrove, most of which occur in this region.
Together, these coastal ecosystems are of immense
ecological and economic importance, providing the
essential basis for much of South Australia's
commercial and recreational fisheries. The coastal
areas of the gulfs however, also support the major
urban and industrial cities of South Australia.
Historically, this province is also of the greatest
maritime significance, reflecting essentially the
early European settlement of this region. However,
present and future urban and industrial activity in
this province, also places this region under the
greatest threat from human activity.
The Fleurieu Peninsula, from Rapid Head to the
Murray Mouth falls within the broad coastal
geomorphological region known as the Coorong
Province, which is dominated by the large, beach
dune barrier lagoon complex known as the
Coorong Lagoon.
1.1 Biogeography of Gulf St Vincent - Fleurieu
Peninsula
Within the Flindersian Province, the Gulf St
Vincent ecosystem encompasses a well-defined
biogeographical region known as the Gulf St
Vincent Bioregion, which extends from West Cape
to Cape Borda (Kangaroo Island), and from Cape
Jervis to Cape Willoughby (IMCRA 1997).
However, the southern coast of the Fleurieu
Peninsula, from Cape Jervis to the mouth of the
Murray River, falls within another marine
biogeographic known as the Coorong Bioregion,
which extends Cape Jervis east to Cape Jaffa, to
Cape Borda (Kangaroo Island) (IMCRA 1997). A
complete physical and ecological biogeographic
description of the Gulf St Vincent Bioregion and
also, the Coorong Bioregion, including marine
fauna and flora, has been described by IMCRA
(1997).
Based on coastal geology, wave climate, and
coastal orientation, Short and Fotheringham (1986),
identified six coastal geomorphological regions (or
subprovinces) for the Kangaroo Island coast:
1
2
3
4
5
6
Southern Yorke Peninsula Subprovince
Central Gulf St Vincent Subprovince
Northern Gulf St Vincent Subprovince
Adelaide Metropolitan Subprovince
Rapid Bay Subprovince
Encounter Bay Subprovince
Based on patterns of biogeography and marine
habitats
(and
also,
existing
coastal
geomorphological classifications), a total of 6
marine biounits have been recognised for the Gulf
St Vincent – Fleurieu Peninsula region:
1.
2.
3.
4.
5.
6.
Sturt Biounit Investigator Biounit Orontes Biounit Clinton Biounit Yankalilla Biounit Encounter Biounit –
Along the southern coast of Australia, marine
biogeographers recognise a major biogeographic
region, known as the Flindersian Province, which
extends from south-west Western Australia to
southern New South Wales and includes the waters
of Victoria and Tasmania. Within this broad
region, the coastal waters of the Great Australian
Bight (west of Robe) are recognised as warm to
cool temperate (in contrast to the cold temperate
waters of the south-east of Australia, east of Robe).
Page 147
GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – STURT AND INVESTIGATOR BIOUNITS
2
2.1
OCEANOGRAPHY
Wave Climate
Wave energy in the Gulfs Province ranges from
moderate at the mouths of both, Spencer Gulf and
Gulf St Vincent, to very low in the upper regions.
Overall, the gulfs are very sheltered ecosystems,
subject to very low to low wave energy regimes.
In Gulf St Vincent, tides are also semi-diurnal but
there is a marked difference in their tidal
amplitudes throughout the gulf. The tidal range
varies from a minimum of approximately 1 m
(spring low water to spring high water) at the south
western tip of Yorke Peninsula, through
approximately 2 m in the lower and mid gulf
waters, to 3 to 3.5 m at the head of the gulfs (de
Silva Samarasinghe & Lennon 1987). Storm
surges of up to 1 m are also possible due to the
effects of strong winds. These effects become
more pronounced in the upper gulf waters due to a
`funnelling effect'. Backstairs Passage is subject to
strong tidal races, and water movement through the
passage is influenced throughout much of the year
by the anti-cyclonic circulation of the Myponga
Eddy, adjacent to the southern Fleurieu Peninsula
(Bye 1976).
In both gulfs, a regular period of minimal tidal
movement occurs, called a `dodge tide' (Gostin et
al. 1984).
2.2
Water Temperature and Salinity
Both Spencer Gulf and to a lesser extent, Gulf St
Vincent, are basically hypersaline-high water
temperature ecosystems. They are also referred to
as `reverse estuaries', because waters of highest
salinities and temperatures occur at the `head' or
upper reaches of the gulfs, rather than near the
open ocean (de Silva Samarasinghe & Lennon
1987). Seasonal surface water temperatures vary
from 12°C to 25.9, while salinities vary from 35.5
ppt to 42.0 ppt (de Silva Samarasinghe & Lennon
1987).
The cooler waters off the southern Fleurieu
Peninsula, are more typical of the Coorong
Bioregion (ie. mean sea surface temperatures
varying from 14°C in winter to 18°C in summer).
The salinity of the waters in Encounter Bay and
Backstairs Passage is also relatively uniform (ie.
35.5 ppt to 36 ppt).
2.3
Currents
In Gulf St Vincent, the coastal water currents are
predominantly in a clockwise direction, affecting
the Yorke Peninsula coast (Bye 1976). Waveinduced littoral currents move in a northerly
direction, affecting both the Yorke and Fleurieu
Peninsula coasts.
Along the southern coast of Yorke Peninsula, tidal
and littoral currents move in a predominantly
easterly direction. On the west coast of the Yorke
Peninsula, littoral currents move predominantly
north.
In both gulfs, the major tidal currents carry fine,
suspended sediment which settle out in the upper
reaches, effectively creating very large sedimentary
basins.
The main process modifying the eastern Yorke
Peninsula coast appears to be windwaves rather
than currents. Exceptions to this occur at only a
few locations, such as at Sultana Point where the
presence of the Troubridge Shoal causes strong
tidal currents across shallow, mobile sandpits.
However, even here, the main erosional force is
still windwaves.
The bottom of Investigator Strait is swept by strong
tidal currents of 50-200 cm/sec; currents are
weakest near the coast of Yorke Peninsula and
Kangaroo Island and increase with increasing
distance from shore, becoming strongest in the
middle of the Strait (Shepherd & Sprigg 1976).
3
CLIMATE
The climate of the Gulfs Province is typically semiarid or `Mediterranean' and as such, is
characterised by hot, dry summers and cool, moist
winters. It is largely influenced by mid-latitude
anticyclones or high pressure systems which pass
from west to east across the continent. Winter
generally brings southerly to southeasterly winds
and low pressure systems which travel across the
Southern Ocean between 40 and 50oS, bringing
frontal activity and rain. Summer brings northerly
to northwesterly winds. The gulfs themselves have
an ameliorating effect on the coastal regions,
producing more temperate weather. The prevailing
wind patterns are also influenced by the gulfs.
Page 148
GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – STURT AND INVESTIGATOR BIOUNITS
Most rainfall falls during winter, however it varies
considerably with latitude, from approximately 500
mm in the south to less than 300 mm in the north.
The climate of the Fleurieu Peninsula, particularly
the south coast, is typically mesothermal or `cool
temperate’, with a distinct winter-spring maximum,
cool winters and warm, dry summers.
4
COASTAL GEOMORPHOLOGY
LANDFORMS
AND
Coastal Geology
Gulf St Vincent, like Spencer Gulf, is a large, semiarid, tidal plain coast, characterised by sedimentary
processes, and an almost complete lack of
significant quantities terrestrial and fluvial
erosional inputs into the gulf waters.
Consolidated Cambrian and Precambrian rocks
form most of the rocky cliffs that line the southerly
and south-easterly margins of Gulf St Vincent and
approaches, and also, the western gulf region, south
of Ardrossan on Yorke Peninsula. Most of the
remainder of the coast of the gulf comprises soft,
sandy and clayey outwash sediments of Permian,
Tertiary of Quaternary age (Shepherd & Sprigg
1976). Tertiary uplift, and former interglacial high
sea-levels, have left a succession of stranded cliffs,
raised shore platforms, and prominent erosional
points, around most of the coastline from the
western extreme of Kangaroo Island, via Cape
Jervis, to Marino near Adelaide. Along this coast,
boulder and cobble littoral beach deposits occur
submerged (eg. Yankalilla Bay, Hallet Cove south),
at, or above, modern beach level at the bases of
many of the cliffs. The most southern of the
Glenelg relict ,sand-covered, submerged shorelines
overlie ancient mangrove swamps with heavy roots
still in situ. Tertiary limestone sediments form
submerged marine outcrops off Ochre Point,
Willunga, Christies Beach (ie. Horseshoe Reef) and
off Noarlunga, however the linear offshore Port
Noarlunga reef is probably a remnant of a
consolidated river deposit (and not a marine
deposit).
Submarine basement rock outcrops are rare in the
gulf, other than granite pedestals at the western
entrance to Investigator Strait, and a submerged
reef (of Proterozoic origin) south west of
Normanville (Shepherd & Sprigg 1976). Permian
shales also outcrop in the 71m deep channel of
Backstairs Passage.
Consolidated and calcrete cemented shell beds
floor much of Investigator Strait and extend onto
the Orontes Shelf (Shepherd & Sprigg 1976). In
Investigator Strait, extensive areas of this broad,
low profile platform reef carry a thin veneer of
coarse shelly sand (and where undermined, forms
ideal habitat and shelter for the Southern Rock
Lobster). Along the north coast of Kangaroo
Island, particularly north of Snug Cove, and over
much of Eastern Cove (Nepean Bay), consolidated
calcareous sand (ie. aeolianite) dunes form
prominent sea floor eminences and rough bottom
topography, which support a rich diversity of
marine life (including algae, sponges, crinoids,
reef-molluscs, lobster, and fish populations).
Along the 10-20 km wide Orontes Shelf,
particularly east of Troubridge Island, the calcreted
Pleistocene shell bed forms extensive flat rocky
surfaces, or low erosional escarpments (5m or more
high). Once again, these provide excellent habitat
for a diversity of marine life. Between Troubridge
Island and Sultana Point, an array of tidally
exposed reefs represent remnants of consolidated
Quaternary sand dunes.
Sand bars or “spits”, caused by strong tidal currents
(and which extend up to 2-4 km offshore, in a
northeast direction), are a dominant feature of the
east and south coast of Yorke Peninsula (eg.
Stansbury, Port Vincent, Sheoak Flat and Black
Point), and represent extensions of stranded
Quaternary beach deposits.
Coastal Geomorphology
In contrast to Spencer Gulf, the coast of Gulf St
Vincent is relatively free of coastal embayments
(with the exception of Salt Creek Bay, near
Edithburgh).
Towards the top end of the Gulf waters are
shallow, and the low coast is backed by mangrove
forests and there are no rock outcrops.
At Ardrossan, a cliff has been excavated in soft
sands and clays, but these cliffs rapidly diminish in
height both, north and south of the town. South of
Rogue Point, the cliffs begin again and from Port
Julia to south of Wool Bay there is an almost
unbroken cliff line between 6-18 metres high, cut
in horizontally layered sandstone and limestone.
Page 149
GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – STURT AND INVESTIGATOR BIOUNITS
There is evidence along the east coast that erosion
is at a minimum at the present time and the
dominant factor in the present cycle of coastline
evolution is deposition, not erosion. Sand is being
transported by currents along the shore longshore
drift. The triangular forelands on which Stansbury
and Port Vincent are built, indicate that sand is
being carried from the south in a northerly
direction and beginning to form a ridge or sandspit.
Black Point and Sultana Point show similar
features although the history of their formation is
rather more complex.
In many places shell beds and typical sandy beach
deposits are found well above present day high
water mark, indicating a period when sea level was
higher than it is today. On the east coast, such
raised beaches are found at Parara Point and
Ardrossan, whilst on the west coast a well marked
raised beach is found at Point Brown.
The west coast of Yorke Peninsula is more
irregular than the east, and consequently a few
more bays have developed at Moonta Bay, Port
Victoria and Hardwicke Bay. Cliffs are not
common, although resistant headlands composed of
hard granitic rocks do occur at Port Gawler, Pearce
Point and along the west coast of Wardang Island.
A series of beach dune ridges built up during
former high still stands of the sea are particularly
well developed east of Point Turton and also near
Port Victoria and Cape Elizabeth. There are even
more extensive ridges on the northern coast of the
foot.
The coasts along the `foot' of Yorke Peninsula
show strong evidence that vigorous erosion is
occurring, due primarily to strong prevailing winds
and associated storm waves coming from the
Southern Ocean. The influence of bedrock on
landscape development can be clearly seen, and all
the prominent headlands are formed of hard
resistant granitic rocks eg. Corny Point, Daly Head
and Point Yorke.
South of the Fleurieu Peninsula (and Kangaroo
Island), the flow of the Murray River has resulted
in the formation of deep and extensive submarine
Murray Canyons which transect the continental
shelf down to the abyssal plains (von der Borch
1979). Shallow sections of these extremely deep
(ie. 4,600 metres) canyons occur in Backstairs
Passage and south of Encounter Bay and the
Murray Mouth.
5
Biology
5.1
General Ecology
A diverse range of major habitats are represented
within Gulf St Vincent. These include: mangrove
forest and their associated samphire and mudflat
habitats; rocky reefs; sandy beaches; estuaries;
subtidal reefs; seagrass meadows and bottom fauna.
It is possible to summarise the major assemblages
and communities present according to the wave
regime experienced in the area. This is by no
means definitive, however, as local variations will
occur.
The more sheltered conditions in Gulf St Vincent
allow extensive stands of mangrove forests,
together with their associated tidal mud flats and
samphire communities.
The general marine intertidal biology of the Gulf St
Vincent has been summarised by Womersley &
Edmonds (1958), and more recently by Womersley
(1990). On coasts of moderate wave energy within
Gulf St Vincent Bioregion (ie. southern coasts of
Gulf St Vincent), the intertidal and sublittoral
fringe of rocky shores are dominated by the brown
algae: Hormosira banksii and Cystophora sp. On
rocky coasts with some wave action, the upper
sublittoral zone is dominated by larger brown
algae, especially Ecklonia radiata, Cystophora
subfarcinata,
C.retorta,
C.polycystidea,
C.moniliformis and other species, Caulocystis
cephalornithos, Cystophyllum onustum and
Sargassum
spp.
(such
as
S.decipiens,
S.lacerifolium), with an understorey of coralline
algae (for eg. Amphiroa anceps, Cheilosporum
elegans), Cladostephus spongiosus and often
species of Caulerpa. On sandy bottom below
rocky areas the seagrasses, Amphibolis and
Posidonia often cover very extensive areas as
dense, often pure, communities.
On coasts of slight wave action, with sandy or
muddy flats or beaches (eg. northern parts of Gulf
St Vincent, excluding rocky outcrops, and reverse
estuaries ie. Barker Inlet), the intertidal and
sublittoral fringe is dominated by samphires, the
Grey Mangrove, Avicennia marina, Hormosira
banksii, Pinna bicolor and the algae Hypnea, and
Spyridia in the sublittoral fringe.
According to von der Borch (1979), the canyons
are probably an important source of nutrient
upwelling, contributing to the significant coastal
productivity in the region.
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GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – STURT AND INVESTIGATOR BIOUNITS
5.2
Subtidal Ecology
Gulf St Vincent has a wide variety of subtidal
benthic habitats. These habitats range from the
deep water invertebrate-dominated benthic
environments of the central gulf and Backstairs
Passage, to the extensive seagrass meadows (and
intertidal mangrove and saltmarsh communities) of
the northern Gulf, and the extensive seagrass-reef
shoal system of the Orontes Bank, to the algaldominated platform reefs scattered throughout
Investigator Strait and the south-eastern region of
the gulf (ie. metropolitan and Fleurieu coast).
Reefs in southern Gulf St Vincent, such as the
“heel” of Yorke Peninsula and Backstairs Passage,
also experience strong tidal currents, and support
great abundance and diversity of reef floral species
(Edyvane and Baker 1996).
Sandy areas (colonised by seagrass), like Spencer
Gulf, dominate much of northern reaches of the
gulf and also include large southern embayments
(ie. Yankalilla Bay and Nepean Bay). Seagrasses
in Gulf St Vincent cover a total area of 2436 km2 ,
which represents approximately 25% of the total
area of seagrass recorded in South Australia.
Seagrass meadows in Gulf St Vincent and
Investigator Strait, like Spencer Gulf, act as key
“carbonate factories”, trapping and also providing
the carbonate basis for sediments in the gulf, ie.
from the destruction of molluscs in shallower,
wave-agitated waters, and bryozoa, calcareous
algae and foraminifera in deeper waters (Shepherd
& Sprigg 1976),.
The subtidal ecology of Gulf St Vincent, Backstairs
Passage and Investigator Strait has been detailed at
length by Shepherd and Sprigg (1976).
Algal communities are prominent on the subtidal
cliffs and rocky shores bordering lower Gulf St
Vincent and Investigator Strait, from low water
mark to a depth of 5-15m (according to locality),
until the rock becomes buried by sand. As in other
parts of South Australia, the nature of the algal
vegetation on subtidal rocky reefs varies
significantly with wave exposure, depth and
substrate geology. Three depth-related zones are
recognised on rocky reefs:
1.
Upper Sublittoral Zone (3-5m) – algal turf
zone - dominated by Cystophora intermedia,
Megabalanus barnacles and short, dense
turfing coralline algae (Haliptilon, Corallina),
and Pterocladia capillacea under (low wave
energy conditions).
2.
3.
Mid Sublittoral Zone (5-15m) – large brown
algae, canopy-forming zone - dominated by
Ecklonia radiata and other large brown algae
(species of Cystophora and Sargassum) and
also, Melanthalia.
Lower Sublittoral Zone (17-29m) – mixed-red
algal zone – dominated by a dense cover of red
algae, including species of Plocamium, and
other small delicate species.
Similarly, algal vegetation also varies significantly
with wave exposure. As in other areas of South
Australia, macroalgal species are commonly
replaced by better adapted species as wave
exposure and water movement varies. This is
particularly the case in the genera Cystophora and
Sargassum, which show a `replacement series’
along a wave exposure gradient. Under conditions
of high wave exposure, rocky reefs are typically
dominated by large brown algae (30-100cm in
height), such as Scytothalia dorycarpa, Ecklonia
radiata, Seirococcus axillaris and species of
Sargassum
(S.bracteolosum,
S.lacerifolium,
S.varians,
S.distichum,
S.linearifolium),
Cystophora (C.moniliformis) and species of
Myriodesma (M.quercifolium, M.integrifolium).
Under moderate wave conditions, reefs are
commonly colonised by species of Cystophora
(C.retorta, C.subfarcinata, C.monilifera) and
Sargassum (S.sonderi, S.paradoxum, S.biforme)
and Sporochnus comosus, Caulocysis uvifera, and
Encyothalia cliftoni. Under conditions of low
wave energy, reefs are dominated by species of
Cystophora botryocystis, C.polycystidea) and
species of Sargassum (S.decipiens, S.spinuligerum,
S.halitrichum) and Scaberia agardhii. Common
grazing animals in algal communities on rocky
reefs
include
sea
urchins
(Heliocidaris
erthrogramma, Phllacanthus parvispinus and
Goniocidaris tubaria), abalone (Haliotis laevigata,
H.ruber, H.scalaris) and the gastropod, Subninella
undulata (Shepherd & Sprigg 1976).
The distribution of bottom dwelling animals within
Gulf St Vincent is influenced by substrate type,
depth, light and hydrological conditions. A total of
6 distinct animal assemblages have been identified
by Shepherd and Sprigg (1976) within Gulf St
Vincent and Investigator Strait:
(1) Pinna-holothurian assemblage – dominant in
the muddy, silty substrates of the upper
reaches of the gulf.
The community is
characterised by the razorfish, Pinna bicolor,
which supports a rich epizoic assemblage of
small sponges, ascidians and bryozoans. The
“milk bottom ascidian”, Phallusia, is also
common.
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GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – STURT AND INVESTIGATOR BIOUNITS
(2) ascidian-scallop assemblage – dominant in
depth of 15-30m, under conditions of low to
moderate water current. Ascidians commonly
occur (attached to shell fragments), together
with scallops and other bivalves, and their
predators, the seastars, Coscinasterias and
Luida are common.
Red algae and the
seagrass, Halophila ovalis , are also common.
(3) bryozoan assemblage – dominant in the
deepest reaches of the gulf. The community is
characterised by large, erect bryozoans (such
as the “basket” bryozoan, Adeona grisea and
others), and massive sponges. Ophiuroids and
crinoids are commonly epizoic on the
bryozoans and sponges.
(4) Malleus/Pinna assemblage – dominant in the
lower eastern part of the gulf, around Rapid
Bay, where the water depths are greatest and
the water current is slightest. The silty muddy
bottom is characterised by the hammer oyster,
Malleus meridianus, the razorfish, Pinna
bicolor and the scallop, Pecten meridionalis,
and small sponges and erect bryozoans.
(5) Heterozostera/Lunulites
assemblage
–
dominant in the sandy, strong tidal flow areas
of Investigator Strait, at depths of 25-35m.
Areas are colonised by sparse Heterozostera
tasmanica, a sparse animal species. Fauna is
limited to the “button bryozoan” Lunulites and
the brachiopod, Magadena cumingi, both of
which lie on the surface of the sand, and
species such the seapen, Sarcophyllum grande,
stalked fan bryozoan, Parmularia, and the
stalked ascidians, Pyura australis and
P.spinifera, which can secure anchorage on the
unstable bottom. Towards the Kangaroo Island
side of Investigator Strait, on rocky reefs,
massive erect, orange sponges occur
everywhere, together with large populations of
its predator, the black and white psolid
holothurian, Ceto cuvieri.
(6) sponge/bryozoan assemblage – dominant in
the deep (>50m), tidal race of Backstair
Passage. This community is characterised by
massive sponges (more than 1 metre high and
across) and large erect bryozoans (such as
Adeona grisea); epizoic crinoids and
ophiuroids are especially abundant on them.
5.3 Seagrass Ecology
Seagrasses (particularly Posidonia australis and
Amphibolis antarctica), as in Spencer Gulf, are
important in trapping and stabilising the sediments
of the Gulf St Vincent. The seagrass leaves baffle
action and reduce water movement to such an
extent that fine suspended particles settle out, and
are trapped by the root mesh of the seagrass
(Shepherd & Sprigg 1976). The sediments of these
seagrass banks consist largely of carbonate skeletal
debris from epiphytic coralline algae, bryozoans,
molluscs and foraminifera, together with
aggregates of aragonite and quartz grains. These
banks have been studied in detail in upper Gulf St
Vincent, where they have been shown to have
caused the shoreline to migrate seaward several
kilometres since sea level stabilised at is present
level approximately 6 000 years ago.
Seagrass beds are well developed in Gulf St Vincent
colonising sandy-muddy areas of tidal flats, and
extending several metres deep. Eight species of
seagrass occur subtidally in the gulf region
(Shepherd & Sprigg). Four of them, Amphibolis
antarctica, Posidonia australis, Heterozostera
tasmanica and Halophila ovalis occur over
extensive areas of sandy seafloor. Amphibolis
antarctica and Posidonia australis occur as dense
monospecific
meadows
stands,
while
Heterozostera tasmanica and Halophila ovalis
occur as scattered plants or clumps of plants,
especially in deeper water. In addition there are
two other species which are less common:
Posidonia ostenfeldii which occurs in scattered
stands on the north coast of Kangaroo Island, and
the eastern shore of the gulf, and Amphibolis
griffithsii, which usually occurs as meadows at
depths of 10-15m, and also as isolated plants
among stands of A.antarctica (Shepherd & Sprigg
1976).
Posidonia australis is the most extensive
community of seagrass in the Gulf St Vincent
region, preferring shallow waters, but extending
down to 30m in Investigator Strait, 20m in the
lower gulf and 10m near the head of the gulf
(Shepherd & Sprigg 1976). The meadows on the
western side of the gulf are usually less dense than
on the eastern side. P.australis grows sympatrically
with P.sinuosa and P.angustifolia in the shallower
part of their range.
Amphibolis antarctica is better adapted than
Posidonia to stronger water movement and mobile
sandy substrates, and generally occurs in small
stands or clumps rather than as extensive meadows
characeristic of Posidonia. A.antarctica occurs
from the uppermost sublittoral zone to 23m, but in
the gulf rarely occurs in depths exceeding about
12m. A.antarctica commonly occurs on sand spits
and bars and is an earlier coloniser in denuded areas
in Posidonia australis meadows, often bordering the
shallow or shoreward side of a Posidonia meadow.
The species also occurs in sandy areas where
underlying rock prevents the establishment of a
Posidonia meadow, or in mixed stands with
Posidonia, under conditions of moderate water
movement.
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GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – STURT AND INVESTIGATOR BIOUNITS
Heterozostera tasmanica is widely but sparsely
distributed in the gulf, and occurs on firm muddy
substrates from low tide level down for 35 m
(Shepherd & Sprigg 1976). Halophila ovalis, like
Heterozostera tasmanica, is also widespread but
sparse in the gulf (particularly in the deeper waters),
and occurs in areas of slight to moderate water
current, from 5-35m depth.
P.sinuosa is widely distributed to a depth of 15m in
sheltered bays and inlets, either in pure stands or
growing sympatrically with P.australis or
P.angustifolia. In more exposed areas it may form
meadows with Amphibolis spp. P.angustifolia grows
subtidally from 2-35 m deep and frequently grows in
deeper water than P.australis. In it's deeper range it
is often found in association with Heterozostera
tasmanica or Halophila australis and in sheltered
positions in it's shallower range in association with
Amphibolis antarctica. Other seagrasses of note in
Gulf St Vincent include: Halophila australis which
grows on sand and mud, from low tide level to 23m
deep; Ruppia spp. (R. tuberosa); Lepilaena marina
which forms extensive low turfs in mid and lower
eulittoral zones on sandy mud tidal flats, often
growing in association with Ruppia tuberosa and
Zostera mucronata; and Amphibolis griffithii which
forms pure stands or mixed communities with A.
antarctica from low tide to depth of 5m. A.griffithii
generally extends into rougher localities and tolerates
lower light intensities than A.antarctica.
5.4
Fish
The marine fish fauna found in the oceanic waters
off Yorke Peninsula and Fleurieu Peninsula is
typical of the Flindersian Province of southern
Australian coastal waters (Glover & Olsen 1985).
As such, many of the species recorded in South
Australian waters, have also been recorded in
southern and south-western Western Australian
waters, and to a lesser extent, in the waters of
western Victoria and north-west Tasmania. There
are some 300 species of known marine fish
recorded off Eyre Peninsula down to the base of the
continental slope, which represents approximately
67% of the species recorded from all South
Australian marine waters (Glover 1982).
The fish fauna of Gulf St Vincent, as with Spencer
Gulf, is typical of the Flindersian Province of
southern Australian coastal waters (Glover & Ling
1976). As such, a total of 216 species have been
recorded from Gulf St Vincent, representing 113
families and 33 orders of fish, including a handful
of sporadic oceanic strays such as Sunfish (Mola
sp.). However, Gulf St Vincent's waters constitute
the type locality for 26 recognised species, 7 of
which appear to be endemic. All are essentially
marine, except a few species which are known to
spend a least part of their life cycles in the more
dilute waters of estuaries, and further upstream in
waterways entering the sea. These latter species
include the Short-Headed Lamprey (Mordacia
mordaxz) and the native Trout (Galaxias
maulatus).
Although the variety of fish in Gulf St Vincent is
relatively small, compared with warmer Australian
waters, there is an abundance of economically
important species. As such, some 14 principal
species are fished in the gulf (Glover & Ling
1976).
The waters of Gulf St Vincent, like Spencer Gulf
are among some of the most commercially
productive in the South Australia. As such, the
most valuable single species fishery in Spencer
Gulf, is the Western King Prawn (Penaeus
latisulcatus).
The marine recreational fishery in Gulf St Vincent
is renowned for the variety of species which
provide abundant and excellent sport for line, spear
and big-game fishers.
5.5
Marine Mammals
In Gulf St Vincent, although there are no major
colonies of seals or herds of whales, individuals of
many species are regularly seen in these waters and
on local beaches.
The Australian Sea Lion
(Neophoca cinerea), and the New Zealand Fur Seal
(Arctocephalus forsteri), haul out on islands in
Investigator Strait (ie. Althorpe Island, Little
Althorpe Island, Seal Island, Haystack Island) and
the north coast of Kangaroo Island, and
occasionally on Adelaide beaches occasionally.
Sightings are also regularly made at various places
around the coast of the Fleurieu Peninsula (eg.
Encounter Bay).
New Zealand Fur Seals have regularly visited West
Island (Victor Harbor) over the last 5 years
however there is presently no evidence of breeding
(S.Shepherd, pers.comm.).
There are also
occasional sightings of Leopard (Hydrurga
leptonyx) and Weddell Seals (Leptonychotes
weddelli).
Some 18 species of whales have been recorded in
South Australian coastal waters (Aitken 1971).
Pilot Whales (Globicephala melaena) enter Gulf St
Vincent occasionally and have gone aground on
local beaches. The largest recorded mass stranding
of whales occurred in 1944 when almost 300 False
Killer Whales (Pseudorca crassidens) went
aground at Port Prime in Gulf St Vincent (Glover
& Ling 1976).
Several species of whales frequent the waters
around Kangaroo Island and Encounter Bay, and
strandings also occur occasionally. In particular,
the endangered Southern Right Whale (Eubalaena
australis) appears regularly in the winter months
during its northward migration from Tasmanian
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GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – STURT AND INVESTIGATOR BIOUNITS
waters to the waters at the Head of the Great
Australian Bight.
Along Encounter Bay in
particular, the whales can be easily from shore.
The Bottlenose Dolphin (Tursiops truncatus) and
the Common Dolphin (Delphinus delphis) are
common in both Spencer Gulf and Gulf St Vincent.
MARINE CONSERVATION VALUES
1
1.1
SIGNIFICANT
BIOLOGICAL
PHYSICAL FEATURES
AND
Biological
Mangrove and Coastal Saltmarshes
Gulf St Vincent (along with Spencer Gulf) contains
some of the most extensive areas of mangrove
forests and tidal wetlands in South Australia (and
the largest areas of temperate mangroves in
Australia) (Edyvane 1996). Associated with the
mangrove habitats are the biologically rich mud
flats, coastal saltmarshes and seagrasses. Together,
mangrove and saltmarsh communities along the
South Australian coast total approximately 82,000
ha, with the largest communities occurring in
Spencer Gulf (46 000 ha) and Gulf St Vincent
(20,000 ha). Other substantial communities occur
in lower Spencer Gulf (6 000ha), on the west coast
of Eyre Peninsula (9 000 ha) and on Kangaroo
Island (7 000 ha) (DELM 1993).
In Gulf St Vincent, mangroves, and associated
coastal saltmarshes, seagrasses and tidal mudflats
dominate the upper portion of the Gulf from Port
Clinton to Port Adelaide.
Mangrove forest comprise a single species, the
Grey Mangrove, Avicennia marina, which forms a
low woodland forest extending from mean sea level
to spring high-tide level. Progressively higher
vegetated zones are a Halosarcia-Sarcocornia
(saltmarsh) association, a Sclerostegia-Halosarcia
(saltmarsh) association and an Atriplex (saltbush)
association (Chinnock 1980).
These tidal wetlands are areas of considerable
productivity and represent significant feeding
habitats for waterfowl and waders, and also
represent key nursery, feeding and breeding areas
for many economically important species of fish
and crustaceans (eg. Western King Prawn, King
George Whiting, Southern Sea Garfish).
Conspicuous algal mats, which form as a result of
sediment trapping by filamentous blue-green algae
are associated with both, the mangrove and
saltmarsh flora. A variety of marine organisms,
mostly gastropods, bivalves, polychaetes and
crustaceans, also live in and on the mangrove mud,
and are a key food source.
Extensive Seagrass Meadows
Gulf St Vincent (along with Spencer Gulf) contain
some of the most extensive areas of temperate
seagrass meadows in Australia (Edyvane 1996).
These extensive seagrass meadows flourish in the
shallow waters of the gulf, generally in waters less
than 15m, and provide the basis for the significant
productivity of the gulf in terms of fisheries and
prawn production. Seagrasses cover approximately
2,436 km2 in Gulf St Vincent, and represent 25% of
the total area of seagrasses recorded in South
Australia (ie. 9,612 km2). Most of the seagrasses
in the gulf are located in the northern reaches of the
gulf (ie. Clinton Biounit, 132,576 ha), in the
Orontes Bank region along the eastern coast of
Yorke Peninsula (ie. Orontes Biounit 51,713 ha),
and along the southern coast of Yorke Peninsula in
Investigator Strait (Sturt Biounit, 23,229 ha).
Seagrass meadows are particularly important for a
number of reasons: as primary producers they
occupy the base of the food chain; they provide
important or “critical” habitats such as nursery,
breeding or feeding areas for the juveniles and
adults of many fish, crustaceans and other marine
animals, including a large number of commercial
species (Bell & Pollard 1989, Howard et al. 1989);
and their extensive root and rhizome systems
stabilise nearshore sediments and sand banks,
enhancing coastal water clarity and reducing
coastal erosion (Scoffin 1971). Seagrass meadows
also support a prolific skeletal biota as infauna and
epiphytes, which in turn, provides the carbonate
basis for sediments in the region.
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GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – STURT AND INVESTIGATOR BIOUNITS
Backstairs Passage
The Backstairs Passage region is unparalleled in
it’s diversity of marine invertebrate assemblages
and is one of the richest areas for sessile
invertebrate fauna in South Australia (Dr Scoresby
Shepherd, SARDI, pers.comm.). The seafloor of
Backstairs Passage has been little studied and
generally the water depths (35-70m) and current
speeds (up to 250 cm/sec) are too great to allow
easy study by diving (Shepherd & Sprigg 1976).
Strong current flows in the narrow Passage provide
optimal conditions for filter-feeding organisms and
many organisms, particularly sponges and
bryozoans, reach very large proportions and also,
importantly, outcompete plant communities in
colonising shallow reefal areas in high current
regions. At 40m depth, the substrate consists of a
planed-off surface of bedrock covered with a thin
layer of sediment made up of coarse sand, small
flat pebbles and biogenic carbonates.
These
sediments form drifts in the lee of the sparse
exposed reef outcrops of Permian shales. At
greater depths (>50m) in the tide race, massive
sponges (more than 1 metre high and across) and
large erect bryozoans (such as Adeona grisea),
dominate the sea bottom; epizoic crinoids and
ophiuroids are especially abundant on them
(Shepherd & Sprigg 1976). In the sediment drifts,
the brachiopod Magadena cumingi reaches
densities up to 80/m2 . The deep water sessile
invertebrate fauna of the Passage is of national
importance with regard to the diversity of
brachiopods (Dr Scoresby Shepherd, SARDI,
pers.comm.), and possibly, global importance if
records of stalked crinoids by the SA Museum (ie.
Dr J Mitchell) are confirmed.
The deepwater sponge-bryozoan habitats of
Backstairs Passage are also of significance as a
habitat which has been depleted in many other
parts of the region, with the advent of prawn
trawling in Gulf St Vincent in 1968, which
removed much of the deepwater bryozoan and
sponge-bryozoan assemblages of the gulf (M.
Olesen, pers.comm.).
Orontes Shelf
The 10-20 km wide Orontes Shelf is an extensive
seagrass-reef shoal system that skirts the eastern
coastline of Yorke Peninsula, from the Marion and
Troubridge Shoals, north to Port Vincent. The
calcreted Pleistocene shell bed forms extensive flat
rocky surfaces, or low erosional escarpments (5m
or more high) and provides excellent habitat for a
diversity of marine life, including sponges,
ascidians, and reef molluscs, and is also an
outstanding mixed fishing ground (Shepherd &
Sprigg 1976). The diversity and productivity of
the area, particularly on the southern reefs, is
enhanced by strong tidal currents. Historically, the
Orontes Shelf region was one of the major
commercial greenlip abalone (Haliotis laevigata)
fishing grounds in South Australia, prior to the
outbreaks of the protozoan parasite, Perkinsus
olseni, in 1985 and 1986 (Goggin & Lester 1995).
Coastal Wetlands of National Importance
A Directory of Important Wetlands in Australia
(ANCA 1996) list the following coastal wetlands of
national importance along Gulf St VincentFleurieu Peninsula Coast:
−
−
−
−
−
−
Point Davenport
Wills Creek
Clinton
Port Gawler and Buckland Park Lake
Barker Inlet and St Kilda
Onkaparinga Estuary
Other Recognised
Significance
Areas
of
Biological
In early 1974, the Department of Fisheries advised
the Yorke Coast Protection District Board of six
significant areas which were under consideration
for declaration as Aquatic Reserves. Areas within
Gulf St Vincent included:
−
tidal
inlet
at
education/purposes)
−
mangrove areas from Price to Port Wakefield
(for fisheries management and conservation
purposes)
−
intertidal reefs between Black Hill and
Troubridge Point (for education purposes)
the islands and surrounding waters of Althorpe
and neighbouring islands (as a conservation
reserve to protect the Blue Groper population)
−
−
Coobowie
and the reefs at Cape
conservation purposes).
Elizabeth
(for
(for
None of these areas has since been declared as
Aquatic Reserves. However, Gleesons Landing is
now a recognised sanctuary for Southern Rock
Lobster.
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GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – STURT AND INVESTIGATOR BIOUNITS
1.2
described. Aboriginal sites, objects and remains
are protected under the South Australian
Aboriginal Heritage Act (1988), and a register of
such sites, objects and remains is kept with the
Aboriginal Heritage Branch of the South Australian
Department of Environment and Planning.
Physical
Orontes Bank
Geological Monuments
There are 28 areas of geological significance in the
Gulfs region which are associated with the
coastline or offshore waters. These areas have
been identified and recognised as "geological
monuments" by the South Australian Museum and
the Geological Society of Australia, and include the
following sites:
1.
Giles Point
2.
Stansbury
3.
Port Vincent (1 km north)
4.
Port Julia Greensand
5.
Pine Point
6.
Hallett Cove
7.
Witton Bluff, South Bank
8.
Onkaparinga Mouth-Seaford
9.
Maslin Bay-Aldinga Bay
10.
Sellicks Beach
11.
Myponga Beach
12.
Carrickalinga Head
13.
Normanville Sand Dunes
14.
South Yankalilla Beach (Little Gorge
Area)
15.
Second Valley Harbour (coastal cliffs)
16.
Middleton Beach
17.
Cape Jervis
18. Encounter Bay region (Port Elliot including
Commodore Point, Pullen Island, The Sisters
Rocks and Freeman Knob)
19.
Deep Creek
20.
Tunkalilla Beach (including the old cliff
line)
21. Headland between Waitpinga Beach and
Parsons Beach
22. West Island, King Beach and King Point
23. Rosetta Head/The Bluff, Petrel Cove and
Wright Island
24.
Victor Harbor, Granite Island and Seal
Island
25.
Victor Harbor (banks of the railway
cutting)
Further details of these areas are supplied in the
relevant regional biounit descriptions below.
2
SIGNIFICANT
CULTURAL
HISTORICAL FEATURES
OR
The following description of Aboriginal and
European history in the Gulfs province is
necessarily brief and selective. The aim is to give
the province a historical perspective with emphasis
on coastal and maritime history. Only details of
Aboriginal historical and cultural sites that have
been published in the available literature are
2.1
Aboriginal
The Yorke Peninsula coast was, in the past,
intensively occupied by Aboriginals of the
Narungga tribe and important evidence of this
occupation is to be found at many places. Most
evidence of Aboriginal occupation is to be found in
the sand dunes along the west coast of the
Peninsula. Amongst the most important areas are
in the Cape Elizabeth/Tiparra Springs dunes and in
the dunes north of Moonta Bay. Other west coast
areas where evidence is know to exist are in the
dunes between Port Hughes and Cape Elizabeth
and in those south of Port Victoria. Other known
areas are at Point Yorke on the South Coast and at
Black Point and Tiddy Widdy on the east coast.
The latter two areas are of considerable
importance, though the Tiddy Widdy dunes have
been looted.
The Fleurieu Peninsula was inhabited by the
Kaurna people. Evidence of Aboriginal occupation
has been found along the coastal regions, but
extensive development and agriculture has
destroyed many significant sites.
2.2
European
Early Discoverers
The first explorer to touch the South Australian
coast was the Dutchman, Francors Thyssen in the
'Gulden Zeepard' in 1627. He sailed eastwards
across the Bight as far as the Nuyts group of
islands, but turned back because of the inhospitable
coast. It was more than 150 years later when the
Frenchman D'Entrecasteaux sailed eastwards to the
Nuyts Archipelago and then to Van Diemen's Land.
The exploration and mapping of the coast of Eyre
Peninsula began with the Englishman Flinders and
his crew who arrived aboard the 'Investigator' at
Fowlers Bay on 28 January 1802.
He proceeded in an easterly direction charting the
outline of the Peninsula and naming features after
places in his native Lincolnshire, after supporters
of the voyage, and from the way the features
appeared to him (eg. Smoky Bay). He also named
islands after his crew, such as at Cape Catastrophe
where the Master of the 'Investigator' (Thistle), and
seven crewmen were drowned. Memory Cove was
so named to commemorate those lost.
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GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – STURT AND INVESTIGATOR BIOUNITS
Following the initial discoverers came whalers and
sealers, and before settlement had begun, there was
a thriving whaling, sealing and fishing industry.
The remains of early sealers' huts and whaling
stations may still be seen on some of the beaches
and offshore islands.
The South Australian
Company, in addition to its operations at Encounter
Bay on Fleurieu Peninsula, established whaling
stations on Thistle Island at the foot of Spencer
Gulf and at Sleaford Bay on the tip of Eyre
Peninsula.
Port Lincoln was founded in March of 1839, and
increased settlement and agriculture began on a
broader scale in the region. Gulf St Vincent was
discovered in March 1802 after Flinders discovered
the Yorke Peninsula when he sailed down the
western side of it after turning back from the head
of Spencer Gulf.
Flinders named Spencer Gulf after Earl Spencer,
Yorke Peninsula after Charles Philip Yorke, and
Gulf St Vincent after Earl St Vincent. All three
men were at some stage acting as the First Lord of
the Admiralty.
Following Flinders, sealers, whalers and land
speculators soon settled the coastal areas of the
Gulfs.
Coastal Ports
The chief method of communication between
Adelaide and the coastal settlements was by sea.
Port Clinton, established in 1863 to supply the
mining towns of Moonta and Kadina, was the first
of the ports on the Gulf St Vincent coast of Yorke
Peninsula. At the minor Gulf St Vincent ports of
Port Price, Port Julia, Pine Point, Wool Bay and
Coobowie, townships grew up at the landward ends
of the jetties constructed for the ketch trade, which
dwindled away until the last of the old time vessels
ceased crossing the Gulf in the mid 1960s.
These jetties are now important reminders of that
time and those that remain are now used by
tourists, divers and fishers.
region
include
the
`Hougamont’,
`Clan
Ranald’,`Willyama’, `Zanoni’, and `Victoria’.
The earliest known shipwreck for South Australia,
the `South Australian', occurred in Encounter Bay
in 1837. Along the Yorke Peninsula coast, nearly a
hundred shipping accidents have been recorded
from cutters to clippers and steamers. The number
of deaths in the accidents has been relatively small.
Half of these incidents occurred on the south coast
of Yorke Peninsula, from Cape Spencer to
Troubridge Shoal. Another three dozen occurred
on the west coast from Reef Head to Cape
Elizabeth and half of these occurred near Wardang
Island and in the harbour of Port Victoria.
For many years Troubridge Shoal was the worst
spot for wrecks, even after the lighthouse had been
built there in 1856, whilst the greatest number of
deaths (40) in any wreck on the Peninsula occurred
with the loss of the `Clan Ranald’ in 1909.
3
The Gulfs Province is the most represented in
terms of Marine Protected Areas (or MPAs) of all
the coastal provinces in South Australia. As such,
9 of the 13 Aquatic Reserves (69%) which have
been declared in South Australia, occur in this
province. No large, multiple use Marine Parks
have been declared in this region. As with other
coastal provinces, the majority of MPAs in this
region comprise `netting closures', many of which
have generally not been formally recognised as
MPAs (see Ivanovici 1985, McNeill 1991). Only
one Marine Sanctuary have been declared along
this coast (ie. Gleesons Landing). This was
established for the protection of the Southern Rock
Lobster.
−
Marine Reserves
Troubridge Hill (460 ha)
St Kilda-Chapman Creek (870 ha)
Barker Inlet-St Kilda (2,055 ha)
Port Noarlunga Reef & Onkaparinga Estuary
(300 ha)
Aldinga Reef (505 ha)
−
Marine Parks
None
−
−
−
−
Shipwrecks
There are a large number of shipwrecks within
Gulf St Vincent – Investigator Strait region.
Within gulf waters north of a line from Cape Jervis
to Troubridge Point and in Encounter Bay,
designated wrecks are protected by the (South
Australian) Historic Shipwrecks Act 1981. In the
waters of Investigator Strait and Backstairs
Passage,
the
(Commonwealth’s)
Historic
Shipwrecks Act 1976 applies. All wrecks older
than 75 years old are granted automatic protection
under the Commonwealth legislation, whether
designated or not. The most notable wrecks in the
CURRENT CONSERVATION STATUS
OF GULF ST VINCENT
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GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – STURT AND INVESTIGATOR BIOUNITS
Netting Closures
−
−
−
−
−
−
−
−
−
−
−
−
−
Edithburgh
Coobowie
Stansbury
Price
Port Wakefield
Port Adelaide (upstream from North Arm)
Outer Harbour and Port Adelaide River
Metropolitan beaches
Patawalonga Lake
Onkaparinga River
Parson's Beach
Waitpinga Beach
Hindmarsh and Inman Rivers
Page 158
GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – STURT AND INVESTIGATOR BIOUNITS
XIX
MARINE BIOGEOGRAPHY AND CONSERVATION VALUES OF THE
STURT AND INVESTIGATOR BIOUNITS
This coastal region encompasses 2 biounits: the inshore Sturt Biounit and the offshore Investigator Biounit. The
Sturt Biounit extends from West Cape on the `foot' of Yorke Peninsula, east to Troubridge Hill (down to a depth
of 30 metres), and covers an area of 183,058 ha and a coastal distance of approximately 105 km, excluding
offshore islands. Offshore islands in the biounit include the Althorpe Islands (Althorpe, Haystack and Seal
Islands), and Royston, Middle and Chinamans Hat Islands. The Investigator Biounit is defined by the 30m
bathymetric contour and encompasses the offshore waters of Investigator Strait.
MARINE BIOGEOGRAPHY
1
3
Major Inshore Habitats
OCEANOGRAPHY
Wave energies are high from West Cape to Cape
Spencer and then moderate from Cape Spencer to
Sultana Point.
2
GEOLOGY
AND
GEOMORPHOLOGY 28
BIOLOGY
COASTAL
−
Major intertidal habitats in the region include
mostly sheltered bays, rocky shores and sandy
beaches.
−
Of the total inshore subtidal habitats mapped
in the Sturt Biounit (34,164 ha), seagrass
meadows comprise 25,611 ha (75.0%), reefs
comprise 5 088 ha (14.9%), and sandy
bottoms comprise 3,465 ha (10.1%).
Dunes and limestone cliffs dominate the coastal
geomorphology of this biounit.
Major Benthic Communities
At Cape Spencer there are aeoleonite and limestone
cliffs, followed by a wide dune belt at Marion Bay.
Hillock Point is aeoleonite and limestone cliffs
with a small section of dunes.
At Point Davenport Conservation Park, a low dunal
area of considerable change in coastal position
occurs. The position of the point is continually
being altered by the growth of spits and the joining
up of those with the land. The area includes a
stranded lagoon occasionally replenished by
extreme tides, and an open tidal inlet.
Sturt Bay is a 20 km section of coast with a well
formed foredune and is backed by a series of
parallel dunes which are the largest and highest
array of parallel dunes in the district.
Macroalgal
−
On high wave-exposed coasts in this region
(eg. West Cape, Cable Hut Bay, Cape
Spencer, Althorpe Island, Haystack Island,
Troubridge Hill), rocky shores are dominated
in shallow waters (ie. <5m) by Ecklonia
radiata,
Acrocarpia
paniculata,
Carpoglossum, species of Cystophora
(C.moniliformis, C.racemosa, C.siliquosa,
C.platylobium), and an understorey of red
algae (Plocamium, Phacelocarpus), green
algae (Caulerpa flexilis, Codium galeatum)
and articulated coralline algae (ie. Haliptilon,
Cheilosporum, Amphiroa, Metagoniolithon).
In deeper waters (ie. 10-15m), reefs are
dominated by Ecklonia, Seirococcus axillaris,
Sargassum fallax, and a mixed red algal
assemblage (ie. Plocamium preissianum,
Sonderopelta, Pterocladia lucida, Ballia
callitricha, Rhodymenia).
28
From Yorke Coast Protection District Study Report (Wynne
1980).
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GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – STURT AND INVESTIGATOR BIOUNITS
−
On moderately exposed coasts (eg. around
Rhino Head, Hillock Point), rocky shores are
dominated in shallow waters (ie. 5m) by
species of Cystophora (C.siliquosa, C.
moniliformis, C.brownii), Scaberia agardhii,
Scytothalia dorycarpa, Caulerpa flexilis and
an understorey of Lobophora variegata.
−
In sheltered areas (eg. around Haystack Island,
Cootes Hill), rocky shores are dominated by
species
of
Sargassum
(S.fallax,
S.verruculosum,
S.heteromorphum,
S.linearifolium), species of Cystophora
(Cystophora
monilifera,
C.moniliformis,
C.expansa), and an understorey of Lobophora
variegata, Caulerpa flexilis and C.trifaria, and
Plocamium angustum.
Seagrasses
−
The wetland is an important habitat for
waterbirds, including a number of wader birds
that occasionally visit the area, and contains
the only conserved stands of Swamp
Paperbark, Melaleuca halmaturorum on Yorke
Peninsula. Threatened species of waterbirds
include the Hooded Plover, Thinornis
rubricollis (Nv, Sv), Latham’s Snipe,
Gallinago hardwickii (Sv), Musk Duck,
Biziura lobata (Sv), Eastern Curlew, Numenius
madagascariensis (Sv) and Fairy Tern, Sterna
nereis (Sv). A total of 26 species of waterbirds
have been recorded in the area: 9 are listed
under international treaties.
Islands of Recognised Conservation Value
•
−
Althorpe Islands Conservation Park
The islands and surrounding waters of
Althorpe Island and neighbouring islands have
a distinctive aquatic flora and fauna
characteristic of rough-water coasts. They are
especially well known for their populations of
Blue Groper, seals and are important seabird
breeding grounds. Dolphins are also found in
this area. Colonies of Australian Sea Lions
(Neophoca cinerea) have been recorded on
Little Althorpe (North and South), Althorpe,
Haystack and Seal Islands (Robinson &
Dennis 1988, Gales et al. 1994). However,
only Little Althorpe (North and South) and
Seal Island represent possible breeding sites
(Gales et al. 1994). Likewise, colonies of
New Zealand Fur Seals (Arctocephalus
forsteri) have also been recorded on Althorpe,
Little Althorpe (South) and Seal Islands
(Shaughnessy et al. 1994). However these
probably represent haul out and basking sites
only.
The conservation park includes
Haystack Island and Seal Island.
•
−
Troubridge Island Conservation
The Troubridge Island Conservation Park (not
to be confused with the Troubridge Hill
Aquatic Reserve off the mainland) is an
important bird breeding area and also has
historical features such as the lighthouse and
associated cottages. However, this island of
sand is subject to the strong wave action of the
Southern Ocean, resulting in it eroding heavily
on one side, but building out elsewhere. As a
result, the island shifts its position.
Extensive seagrass meadows occur in Marion,
Foul, Sturt and Waterloo bays, and also in the
lee of islands (eg. Althorpe, Haystack islands).
Meadows are dominated by species of
Posidonia
(P.sinuosa,
P.angustifolia),
Amphibolis antarctica, and also, Halophila
australis.
Coastal and Offshore Islands (or Reefs)
−
Althorpe, Little Althorpe (North and South),
Haystack and Seal Islands (Althorpe Islands
Conservation Park).
−
Royston, Middle and Chinamans Hat Islands
(part of Innes National Park).
MARINE CONSERVATION VALUES
1
1.1
SIGNIFICANT
BIOLOGICAL
PHYSICAL FEATURES
AND
Biological
Coastal and Marine Wetlands of National
Importance
−
Point Davenport (and the Point Davenport
Conservation Park) has been identified as a
wetland of national importance (see ANCA
1996). Point Davenport is a rare example of a
stranded coastal lagoon on Yorke Peninsula.
The semi-stranded tidal lagoon enters the sea
via a tidal inlet, and is inundated during
extreme high tides usually once or twice a
year.
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GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – STURT AND INVESTIGATOR BIOUNITS
Seagrasses cover approximately 2,436 km2 in
Gulf St Vincent, with most of the seagrasses
located in the northern reaches of the gulf (ie.
Clinton Biounit, 132,576 ha), in the Orontes
Bank region along the eastern coast of Yorke
Peninsula (ie. Orontes Biounit 51,713 ha), and
along the southern coast of Yorke Peninsula in
Investigator Strait (Sturt Biounit, 23,229 ha).
Other Areas of Recognised Conservation
Significance
•
−
•
−
•
−
Innes National Park
Preserves the largest area of natural bushland
remaining on the Yorke Peninsula, and
preserves the habitat of the Western Whipbird.
It is characterised by a sandy undulating plain
with dunes and salt lakes, or low cliffs along
the coastline.
The magnificent and
spectacular coastal scenery is one of the major
attractions of this park, which includes cliffs,
wave cut platforms, rocky headlands and
sandy beaches. Typical coastal dune and clifftop vegetation is backed by mallee and teatree
scrub. It is still possible to see the remains of
the shipwreck `Ethel' near Reef Head.
Royston, Middle and Chinamans Hat islands
are included in the national park.
Troubridge Hill Aquatic Reserve.
Consists of intertidal and subtidal reef
platforms: coarse-grain sandy bottom and
sandy beaches. The intertidal reef platform
extends 50m offshore before falling away
sharply to 15m depth. The crevices and
overhangs are colonised by many benthic
organisms including gorgonian corals. The
wreck of the `Clan Ranald' lies in 22m depth
within the reserve. The area from Troubridge
Point to Port Moorowie is on the Register of
the National Estate.
Troubridge Shoals.
Troubridge Shoals have large sponge
`gardens'. The Troubridge region (including
Troubridge and Cootes Hills, Troubridge Point
and Marion Reef) contains abundant and
diverse assemblages of large red algal species
(Osmundaria, Cladurus, Erythroclonium,
Areschougia) and other mixed red species.
The dominance of large red algal species is an
unusual feature at a statewide biogeographic
level. The Troubridge area is also the site
where the newly described (Womersley, in
prep.) Amphiroa gracilis is locally abundant.
Seagrass Meadows
−
The seagrass meadows of this biounit
represent the third largest areas in Gulf St
Vincent, after the Clinton and Orontes
Biounit. These extensive seagrass meadows
flourish in the shallow waters, generally in
waters less than 15m, and provide the basis for
the significant productivity of the region in
terms of fisheries and prawn production.
1.2
−
Physical
Sturt Bay: considered to be a "magnificent
stretch of beach"29 with the largest and highest
array of parallel dunes in the district as a
scenic backdrop.
Geological Monuments
−
Meteor Bay (2 km east of Hillock Point):
Proterozoic basement rocks on the shore
platform.
−
Point Moorowie: Permian glacigenes and
unconformity with Ardrossan Clays and sand
rock. The site is also on the Register of the
National Estate.
2
2.1
OTHER VALUES
Commercial Fisheries
A wide variety of commercial fishing occurs in the
coastal and offshore waters of this biounit. Single
species fisheries include Southern Rock Lobster,
Abalone and Western King Prawn. There is also a
large marine scalefish industry in the region.
Western King Prawn
This biounit is located within the waters of the Gulf
St Vincent prawn fishery, which comprises 10
license holders (ie. boats). All vessels fish within
the waters of the Gulf St Vincent and Investigator
Strait biounits (ie. Sturt, Investigator, Orontes,
Clinton, Yankalilla, Nepean, Encounter, St
Vincent). In 1995/96 and 1996/97 a total of
258,459 and 210,581 kg was caught for this
fishery, with a total effort of 2,996 and 3,235 hours,
respectively (or 11.38% and 10.41% of the total
catch for Western King Prawn in South Australian
waters).
29
From Yorke Coast Protection District Study Report (Wynne
1980).
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GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – STURT AND INVESTIGATOR BIOUNITS
Southern Rock Lobster
In 1995/96 and 1996/97 a total of 19 and 19
licensed operators fished in the south western and
southern Yorke Peninsula (and Investigator Strait)
region (ie. Fishing Zone 40), catching
approximately 71,795 and 64,785 kg of lobsters,
respectively (or 1.40% and 1.27% of the total catch
for Southern Rock Lobster in South Australian
waters).
2.2
There is currently no aquaculture in the area. The
Gulf St Vincent/Fleurieu Aquaculture Management
Plan (Berggy 1996) proposes the following
aquaculture development in this region:
Lower Yorke Peninsula Policy Area
−
Lower Yorke Peninsula Zone (all coastal
waters from Cape Spencer east to Marion
Bay/Stenhouse Bay Aquaculture Zone,
including Althorpe Islands, Haystack Island
and Seal Island) – zoned for maintenance of
visual and conservation values. Licenses will
not
be
considered
for
aquaculture
development in this zone.
−
Marion Bay/Stenhouse Bay Aquaculture Zone
(coastal waters of Stenhouse and Marion bays,
within 3nm of the coast) – zoned for
aquaculture development. Licenses will be
considered for a total of 20ha of aquaculture
development in this zone, excluding the
cultivation of the Pacific Oyster.
−
Foul Bay/Moorowie Management Zone
(coastal waters of Foul, Sturt and Waterloo
bays, within 3nm of the coast, from west of
Hillock Point to Troubridge Hill) – zoned for
aquaculture development. Licenses will be
considered for a total of 20ha of aquaculture
development in this zone, excluding the
cultivation of the Pacific Oyster.
Abalone
Some Greenlip and Blacklip Abalone is
commercially harvested in the western section of
this biounit (ie. MapCode 23D, Stenhouse Bay, see
Pondalowie Biounit), however there is no
commercial harvest of either Blacklip or Greenlip
Abalone in the Sturt Bay, Troubridge Shoals and
Sultana Point region.
Marine Scalefish Fisheries
During 1995/96 and 1996/97, 54 and 51
commercial licence holders (made up of Marine
Scalefish, Restricted Marine Scalefish licence
categories) caught commercial marine scalefish
species from the in the south western and southern
Yorke Peninsula (and Investigator Strait) region
(ie. Fishing Zone 40), respectively.
License
holders expended approximately 1,742 and 1,668
boat days effort fishing these waters during
1995/96 and 1996/97, respectively. The marine
scalefish catch for this region (ie. Fishing Zone 40)
represented 200,171 kg in 1995/96 and 211,150 kg
in 1996/97(or 1.93% and 2.08% of the total catch
for the marine scalefish fishery in South Australian
waters).
Although license holders are not restricted to fishing
in this biounit, the following licenses are registered in
this area:
−
Marion Bay: 3 Rock Lobster, 1 restricted
marine scalefish, 3 unrestricted marine
scalefish
−
Port Moorowie: 1 restricted marine scalefish,
1 unrestricted marine scalefish
−
Foul Bay: 4 unrestricted marine scalefish
−
Stenhouse Bay: 1 unrestricted marine scalefish
Aquaculture
2.3
Recreation and Tourism
Fishing
−
Cape Spencer: beach and rock fishing. Major
species: Sand Flathead, Yelloweye Mullet,
Australian Salmon, Sweep, Garfish, Tommy
Rough, Toothbrush Leatherjacket and Silver
Drummer.
−
Stenhouse Bay: jetty and rock fishing. Major
species: Yelloweye Mullet, Sweep, Garfish,
Tommy Rough and Southern Calamari.
−
Marion Bay: boat and jetty fishing. Major
species: King George Whiting, Yelloweye
Mullet, Snapper, Snook, Garfish, Tommy
Rough and Southern Calamari.
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GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – STURT AND INVESTIGATOR BIOUNITS
−
−
Hillock Point and Butlers Beach: beach and
rock fishing. Major species: Sand Flathead,
Yelloweye Mullet, Australian Salmon,
Mulloway, Snook, Sweep, Garfish, Tommy
Rough, Toothbrush Leatherjacket and Silver
Drummer.
−
Butlers Beach: camping.
−
Marion Bay and near Point Yorke: scenic
lookouts.
−
Lighthouse, west of Troubridge Point.
Troubridge Point: beach and rock fishing.
Major species: Sand Flathead, Yelloweye
Mullet,
Australian
Salmon,
Snapper,
Mulloway, Snook, Sweep, Tommy Rough,
Toothbrush
Leatherjacket
and
Silver
Drummer.
−
Troubridge Hill Aquatic Reserve: SCUBA
diving, recreational fishing, historic shipwreck
(ie. `Clan Ranald’), coastal scenic qualities.
Tourism
−
Stenhouse Bay jetty: popular for fishing and
SCUBA diving.
−
Innes National Park: camping, spectacular
coastal scenery and SCUBA diving. The
small holiday and fishing village of
Pondalowie Bay, and South Island are popular
camping sites and are excluded from the
national park. The Innes National Park region
is a very popular site for SCUBA diving and
contains many spectacular dives. Pondalowie
Bay, Reef Head and the Gap, Emmes Reef (5
miles off from the Gap), Haystack Island and
the Althorpe Islands, Chinamans Hat Island,
and the Stenhouse Bay jetty, are all recognised
dive spots and are listed in `Dive South
Australia: The Best Dive Sites in South
Australia’ (Diving Industry Association of
South Australia). All these reef dives are
excellent dives, with abundant marine life,
including seals and sea lions (ie. Althorpe
Islands, Haystack Island, Seal Island), but
require good weather and/or generally
experienced divers. Stenhouse Bay jetty has
abundant marine life on its pylons and is also
a good, accessible site for underwater
photography.
−
SCUBA diving: other recognised and popular
dive spots in the region include Foul Bay and
Cable Hut Bay, `Clan Ranald’ shipwreck,
Troubridge Point and Troubridge Hill, and
Troubridge Shoal. All are listed in `Dive South
Australia: The Best Dive Sites in South
Australia’ (Diving Industry Association of
South Australia).
2.4
Scientific Research and Education
−
Fisheries research in this area includes, regular
catch and effort monitoring of the major
commercial fisheries in the region (Abalone
and marine scalefish); regular research and
monitoring of larval fish stocks; regular
research and monitoring of Blacklip and
Greenlip Abalone field stocks.
−
The intertidal reefs between Black Hill and
Troubridge Point are used on a regular basis
for teaching and research purposes by the
University of Adelaide.
An educational
reserve was proposed for this area by the
Department of Fisheries in 1974.
2.5
Adjacent Land Use
National and Conservation Parks
−
Innes National Park (9,232 ha): includes:
Royston, Middle and Chinamans Hat islands.
−
Althorpe Islands Conservation Park (25 ha):
includes Haystack Island and Seal Island.
−
Point Davenport Conservation Park (239 ha).
−
Troubridge Island Conservation Park (314 ha).
Urban Centres
No major urban centres, although there are
numerous holiday shacks along the coast. Marion
Bay has a permanent mooring facility for
commercial and recreational craft.
Agriculture/Industry
The adjacent land in this biounit is predominantly
agricultural.
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GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – STURT AND INVESTIGATOR BIOUNITS
2.6
Significant Cultural and Historical
Features
−
4
Aboriginal
Not known.
Formby Bay - Innes National Park30
−
European
Shipwrecks
−
The Investigator Strait is notable for a number
of shipwrecks along its coast. The State
Heritage Branch of the Department of
Environment and Aboriginal Affairs lists 26
known wrecks along the coast between Cape
Spencer and Troubridge Point, and there are
others whose locality is not known (Ashman
1996). Some of the more notable wrecks
include:
−
`S.S. Clan Ranald’ (1900-1909): a single
screw turret deck steamer which sank off
Troubridge Hill. 44 of the 63 crew were lost.
The wreck is located within Troubridge Hill
Aquatic Reserve.
−
`Iron King’ (1867-1873): a three-masted iron
ship that ran aground on Troubridge Shoals.
−
`Marion’ (1850-1851): a three-masted wooden
ship that struck a reef just south of Troubridge
Shoals. Its remains are located on Marion
Reef, a shallow limestone reef, south of
Troubridge Island.
−
`Ethel’: an iron barque of 700 tons that went
ashore in January 1904 near Reef Head.
Retrieval attempts were unsuccessful, and
today one of her boilers can still be seen
poking out of the sand near Reef Head.
3
CURRENT CONSERVATION STATUS
OF THE STURT BIOUNIT
−
Marine Reserves
Troubridge Hill (460 ha)
−
Marine Parks
None
−
Netting Closures
None
AREAS OF HIGH CONSERVATION
VALUE IN THE STURT BIOUNIT
Prime
IUCN
Conservation
Values:
biodiversity, education, social, cultural values
(IUCN Category II). IUCN Identification
Criteria: naturalness (not subjected to humaninduced change), biogeographic (representative
marine habitats, geological monuments-Browns
Beach), ecological (diversity of marine habitats,
high marine biodiversity, reef fish populations Blue Groper, breeding populations-Little
Penguins, Silver Gulls, seabirds-Black-faced
Cormorants, Pied Cormorant, Reef Heron, Pied
Oyster Catcher, Sooty Oyster Catcher, Grey
Plover, Hooded Dotterel, Red Neck Stint, Black
Winged Stint, Pacific Gull, Caspian Tern,
Crested Tern, Silver Gull, Shy Albatross, Little
Pied Cormorant, Banded Plover, Banded Stilt,
Little Tern), economic (tourism, Greenlip
Abalone, Southern Rock Lobster, marine
scalefish fisheries), social (`Ethel' shipwreck,
recreation,
diving,
education-Gleesons
Landing-Daly Head), national significance
(potential for listing on Register of National
Estate), practicality (insulation, accessibility,
compatibility-adjacent to Innes National Park).
Althorpe Islands 31
−
Prime IUCN Conservation Values: rare and
endangered species/habitats, biodiversity, social
values (IUCN Category IA). IUCN
Identification Criteria: naturalness (not
subjected
to
human-induced
change),
ecological, (high marine biodiversity, breeding
colonies and haul out sites for Australian Sea
Lions and New Zealand Fur Seals, reef fish
populations-Blue
Groper,
colonies
of
`vulnerable' Fairy Terns, Black-faced Shags,
Little Penguins, White-faced Storm Petrels,
White-bellied Sea Eagles), economic (abalone,
rock lobster fisheries, tourism), social
(recreation, diving), practicality (insulation,
compatibility-adjacent to Althorpe Islands
Conservation Park).
30
Gleesons Landing to Daly Head was nominated for
establishment as an Aquatic Reserve by the former South
Australian Department of Fisheries in 1974, for educational
purposes (Wynne 1980).
31
The islands and surrounding waters of Althorpe Island and
neighbouring islands were nominated for establishment as an
Aquatic Reserve by the former South Australian Department of
Fisheries in 1974, as a conservation reserve to protect populations
of Blue Groper (Wynne 1980).
Page 164
GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – STURT AND INVESTIGATOR BIOUNITS
Point Davenport Conservation Park
−
Prime
IUCN
Conservation
Values:
biodiversity,
rare
and
endangered
species/habitats, social values (IUCN Category
II). IUCN Selection Critera: naturalness (not
subjected
to
human-induced
change),
biogeographic (rare coastal habitat, geological
monuments-Port Moorowie, Sturt Bay)
ecological (extensive seagrass meadows,
threatened species of waterbirds-Hooded
Plover, Eastern Curlew, Fairy Tern, nursery,
feeding area for economic species-marine
scalefish), economic (marine scalefish fisheries,
tourism), social (recreation, aesthetic values),
national significance (Wetland of National
Importance-Point Davenport Conservation
Park, potential listing on Register of National
Estate), practicality (insulation, compatibilityadjacent to Point Davenport Conservation
Park).
Troubridge Shoals – Marion Shoals
−
32
Prime
IUCN
Conservation
Values:
biodiversity,
rare
and
endangered
species/habitats, social values (IUCN Category
II). IUCN Identification Criteria: naturalness
(not subjected to human-induced change),
ecological, (range of coastal wetland habitats,
breeding colonies Little Penguins, Black-faced
Shag, Pied Cormorant, Crested Tern, Silver
Gull, `vulnerable' Fairy Terns), economic
(marine scalefish fisheries, Southern Rock
Lobster, tourism), social (historic shipwrecks `SS Clan Ranald', `Iron King', `Marion',
recreation, diving, yachting), practicality
(practicality, compatibility, Troubridge Hill
Aquatic
Reserve,
Troubridge
Island
Conservation Park).
32
The intertidal reefs between Black Hill and Troubridge Point
were nominated for declaration as an Aquatic Reserve by the
former South Australian Department of Fisheries in 1974, for
marine educational purposes (Wynne 1980).
Page 165
GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – ORONTES BIOUNIT
XX
MARINE BIOGEOGRAPHY AND CONSERVATION VALUES OF THE
ORONTES BIOUNIT
This biounit extends from Troubridge Hill to Ardrossan on the eastern side of Yorke Peninsula and covers an
area of 183,762 ha. The biounit faces east into Gulf St Vincent.
Erythroclonium
angustum,
Osmundaria,
Plocamium spp. Cliftonaea, Cladurus,
Areschougia); mixed corallines (Amphiroa
gracilis [a newly described species] and
A.anceps;
Haliptilon,
Cheilosporum,
Metagoniolithon) some mixed Sargassum
(S.decipiens,
S.fallax,
S.linearifolium,
S.verruculosum); and some mixed green algae
(Caulerpa brownii, Codium pomoides,
Dictyosphaeria).
MARINE BIOGEOGRAPHY
1
OCEANOGRAPHY
This area is typified by low wave energies.
2
GEOLOGY
AND
GEOMORPHOLOGY 33
COASTAL
From Sultana Point to Ardrossan, the coastal
geomorphology is dominated by limestone cliff
slopes. A few areas of sandy beaches with small
dunes occur at Stansbury, Port Vincent and Black
Point.
−
On moderately exposed shores and reefs (eg.
Troubridge Point), rocky areas are dominated
in shallow areas (ie. 5m) by Cystophora
moniliformis,
diverse
mixed
reds
(Erythroclonium, Rhabdonia, Areschougia,
Heterosiphonia, Webervanbossea, Dasya,
Laurencia,
Euptilota,
Ptilocladia,
Asparagopsis, Champia); some mixed
Sargassum spp. (S.decipiens, S.lacerifolium,
S.spinuligerum); and an understorey of
Lobophora variegata.
−
On sheltered shores and reefs (eg. Pine Point,
Adrossan), rocky areas are dominated in
shallow areas (ie. 5m) by Sargassum spp.
(S.decipiens, S.lacerifolium, S.spinuligerum),
the red alga, Botrycladia obovata and
Caulocystis
ulvifera.;
Cystophora
moniliformis,
diverse
mixed
reds
(Erythroclonium, Rhabdonia, Areschougia,
Heterosiphonia, Webervanbossea, Dasya,
Laurencia,
Euptilota,
Ptilocladia,
Asparagopsis, Champia); some mixed and an
understorey of Lobophora variegata.
Wide muddy tidal flats occur at Salt Creek Bay,
together with a tidal inlet. At Ardrossan there are
spectacular eroding clay cliffs.
3
BIOLOGY
Major Inshore Habitats
−
Major intertidal habitats in the region include
mostly sheltered, low rocky shores, bays and
some sandy beaches.
−
Of the total inshore subtidal habitats mapped
in the biounit (91 539 ha), seagrass meadows
comprise 51 713 ha (56.5%), reefs comprise
33 745 ha (36.9%), and sandy bottoms
comprise 6 081 ha (6.6%).
Major Benthic Communities
•
−
Macroalgal
On high wave-exposed shores and reefs in the
region (eg. Troubridge Hill, Marion Reef),
reef areas are dominated in shallow areas (ie.
5m) by mixed species of Cystophora
(C.moniliformis, C.racemosa, C.siliquosa,
C.platylobium); Ecklonia radiata; diverse
mixed large reds (including locally prolific
•
−
Seagrasses
Within this biounit, extensive seagrass
meadows occur throughout the Orontes Bank,
and in sheltered embayments (eg. Coobowie,
Adrossan). Sandy sediments are commonly
coloniesed by species of Posidonia
(P.sinuosa, P.angustifolia) and Halophila
australis, which often occurs adjacent to reef
communities and in deep water (ie. 20m).
33
From Yorke Coast Protection District Study Report (Wynne
1980).
Page 166
GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – ORONTES BIOUNIT
In these deeper water parts of the gulf, the soft
sediments
are
dominated
by
faunal
assemblages, such as bivalve molluscs (ie.
scallops, Pinna bicolor), bryozoans, ascidians
and holothurians.
1.2
−
Physical
−
Marion Reef, Orontes Bank.
−
Troubridge Island.
The "Orontes Bank" is a major deep-seated
geological structure that extends offshore from
Edithburgh to the northern part of the gulf.
The edge of the Gawler Craton has produced
an intense magnetic anomaly associated with
it. The exposed tertiary sediments form a
shallow bank extending from approximately
Stansbury to Port Julia, and is a few hundred
metres wide. Associated with these sediments
is modern reefal activity and productivity.
Rivers/Estuaries
Geological Monuments
Coastal and Offshore Islands (or Reefs)
−
Salt Swamp Creek (Coobowie).
−
Giles Point: coastal cliffs, consisting of an
outcrop of Pliocene Hallett Cove Sandstone
and Cainozoic beds.
−
Stansbury - Port Vincent: limestone with
solution features.
−
Port Vincent (1 km north): coastal faulting and
Permian erratics.
−
Port Julia Greensand: Type section and
monocline.
MARINE CONSERVATION VALUES
1
1.1
−
−
SIGNIFICANT
BIOLOGICAL
PHYSICAL FEATURES
AND
Biological
Seagrass Meadows
The seagrass meadows of this biounit
represent the second largest areas in Gulf St
Vincent, after the Clinton Biounit. These
extensive seagrass meadows flourish in the
shallow waters, generally in waters less than
15m, and provide the basis for the significant
productivity of the region in terms of fisheries
and prawn production. Seagrasses cover
approximately 2,436 km2 in Gulf St Vincent,
with most of the seagrasses located in the
northern reaches of the gulf (ie. Clinton
Biounit, 132,576 ha), and in the Orontes Bank
region along the eastern coast of Yorke
Peninsula (ie. Orontes Biounit 51,713 ha), and
also, along the southern coast of Yorke
Peninsula in Investigator Strait (Sturt Biounit,
23,229 ha).
Extensive beds of bryozoans associated with
the exposed sediments of "Orontes Bank" (see
below).
2
2.1
OTHER VALUES
Commercial Fisheries
The major single species fisheries in this area is the
Western King Prawn. There is also a substantial
marine scalefishery in the region.
Western King Prawn
This biounit is located within the waters of the Gulf
St Vincent prawn fishery, which comprises 10
license holders (ie. boats). All vessels fish within
the waters of the Gulf St Vincent and Investigator
Strait biounits (ie. Sturt, Investigator, Orontes,
Clinton, Yankalilla, Nepean, Encounter, St
Vincent). In 1995/96 and 1996/97 a total of
258,459 and 210,581 kg was caught for this
fishery, with a total effort of 2,996 and 3,235 hours
(ie. 86.27 and 65.09 kg/hr, Catch Per Unit Effort),
respectively (or 11.38% and 10.41% of the total
catch for Western King Prawn in South Australian
waters).
Page 167
GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – ORONTES BIOUNIT
Abalone
Commercial harvesting of Greenlip Abalone is
neglible within the Orontes Biounit, (ie. MapCode
22B, 24B-D, Sultana Point to Ardrossan region).
No Greenlip were harvested in this region during
1995/96. No Blacklip Abalone was commercially
harvested in this region during 1994/95 and
1995/96.
2.2
Aquaculture
Oyster farming, involving both the native oyster,
Ostrea angasi and later the Pacific Oyster,
Crassostrea gigas, has been carried out
intermittently at Stansbury for many years One
lease is currently in operation at Stansbury. The
Gulf St Vincent/Fleurieu Aquaculture Management
Plan (Berggy 1996) proposes the following
aquaculture development in the region:
Marine Scalefish Fisheries
Gulf St Vincent West Policy Area
During 1995/96 and 1996/97, 37 and 30
commercial licence holders (made up of Marine
Scalefish, and Restricted Marine Scalefish licence
categories) caught commercial marine scalefish
species from the Orontes Biounit region (ie.
Fishing Zone 34), respectively. License holders
expended approximately 1958 and 1247 boat days
effort fishing these waters during 1995/96 and
1996/97, respectively. The marine scalefish catch
for this region (ie. Fishing Zone 34) represented
113,844 kg in 1995/96 and 75173 kg in 1996/97(or
1.09% and 0.74% of the total catch for the marine
scalefish fishery in South Australian waters).
Although license holders are not restricted to fishing
in this biounit, the following is an approximate
number of licenses which are registered in this area:
−
Port Vincent: 3 Rock Lobster, 6 unrestricted
marine scalefish
−
Coobowie: 1 restricted marine scalefish, 2
unrestricted marine scalefish
−
Edithburgh: 2 restricted marine scalefish, 7
unrestricted marine scalefish
−
Stansbury: 1 restricted marine scalefish, 4
unrestricted marine scalefish
−
Port Julia: 2 unrestricted marine scalefish
−
Ardrossan: 1 experimental crab, 1 restricted
marine scalefish
−
Troubridge Shoals Zone (coastal waters from
Troubridge Point to Edithburgh jetty) – zoned
for scenic and conservation uses. Licenses
will not be considered for aquaculture
development in this zone.
−
Coobowie Bay Aquaculture Zone (coastal
waters of Coobowie Bay, from Edithburgh
jetty to Giles Point) – zoned for aquaculture
development. Licenses will be considered for
a total of 60ha of aquaculture development in
this zone, excluding bivalve culture using
racks.
−
Stansbury Aquaculture Zone (coastal waters,
within 1km of the coast, from Oyster Bay to
North Spit) – zoned for aquaculture
development. Licenses will be considered for
a total of 80ha of aquaculture development in
this zone.
−
Yorke Peninsula Inshore Management Zone
(inshore waters, within 2nm of the coast, from
North Spit to Rogues Point and Giles Point to
Stansbury Aquaculture Zone) – zoned for
aquaculture development. Licenses will be
considered for a total of 100ha of aquaculture
development in this zone.
−
Yorke Peninsula Offshore Management Zone
(offshore waters, from 2nm to offshore
boundary of policy area) – zoned for offshore
aquaculture development. Licenses will be
considered for a total of 100ha of aquaculture
development in this zone.
−
Ardrossan Zone (coastal waters
surrounding the port of Ardrossan) –
zoned for commercial, navigation and
recreational uses. Licenses will not be
considered for aquaculture
development in this zone.
Page 168
GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – ORONTES BIOUNIT
2.3
Recreation and Tourism
−
SCUBA diving: Troubridge Shoal (also
containing the wreck of the `Iron King’),
Coobowie artificial reef, the `Zanoni’
shipwreck (off Ardrossan), and the
Edithburgh, Port Giles, Wool Bay and
Ardrossan jetties are all popular and
recognised dive spots and are listed in `Dive
South Australia: The Best Dive Sites in South
Australia’ (Diving Industry Association of
South Australia). Edithburgh jetty is
recognised as one of the best jetty dives in
South Australia and is a popular dive training
site and location for underwater photography.
Most dives, except Troubridge Shoal are
suitable for novice divers.
Fishing
−
Edithburgh, Tapley Shoal and Troubridge
Shoals: boat, jetty and shore fishing. Major
species: King George Whiting, Sand Flathead,
Yelloweye Mullet, Snapper, Garfish, Tommy
Rough, Trevally, Toothbrush Leatherjacket
and Southern Calamari.
−
Port Giles: jetty fishing. Major species: King
George Whiting, Snapper, Snook, Garfish,
Tommy Rough, Trevally, Silver Drummer and
Southern Calamari.
−
Stansbury: jetty fishing. Major species: King
George Whiting, Snapper, Snook, Garfish,
Tommy Rough, Trevally, Silver Drummer and
Southern Calamari.
−
Port Vincent: boat and jetty fishing. Major
species: King George Whiting, Sand Flathead,
Yelloweye Mullet, Australian Salmon,
Snapper, Mulloway, Snook, Garfish, Tommy
Rough and Southern Calamari.
−
Ardrossan: boat and jetty fishing. Major
species: King George Whiting, Sand Flathead,
Yelloweye Mullet, Australian Salmon,
Snapper, Mulloway, Snook, Garfish, Tommy
Rough and Southern Calamari.
−
2.4
−
Port Vincent Primary School and Aquatic
Centre plays a major role in school-based
marine and coastal educational activities in the
Yorke Peninsula region. The centre offers a
range of courses and educational activities on
marine and coastal habitats and species,
utilising the local environments of Port
Vincent, and also hosts a wide range of marine
aquaria for project work. The centre has
received several national awards for its marine
educational activities and also provides a wide
range of outdoor activities, including
snorkelling, for students.
−
Salt Creek Bay (Coobowie) is a significant
site for scientific research and education into
marine ecological processes. The tidal inlet
and rocky shores of the bay are used both, for
marine biological research and education. A
marine research field station is located at
Coobowie and although, it is owned by the
University of Adelaide, it is frequently used
by various institutions, including the
University of Adelaide, Flinders University,
Melbourne University and Monash University.
While it is frequently used for undergraduate
teaching purposes, it is also commonly used
by postgraduate research students and visiting
interstate and overseas scientists.
On
occasions the research station has been let to
diving clubs, who use it as a base camp when
diving in local waters. It is the only marine
research field station of it’s type in South
Australia. As such, this area was proposed as
an educational reserve in 1980 34.
There is an artificial reef near Ardrossan
(sunken barge) and Giles Point (tyre modules).
Tourism
−
Coobowie: fishing and boating.
−
Port Vincent: swimming and yachting (has a
safe swimming beach).
−
Ardrossan: boating and fishing.
Scientific Research and Education
34
Yorke Coast Protection District Study Report (Wynne (1980).
Page 169
GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – ORONTES BIOUNIT
−
The organisms living on the pylons of
Edithburgh jetty have been the subject of
many of these scientific research studies;
primarily to gain an understanding of the life
history dynamics of sessile marine organisms
(Butler 1982). The pylons of Edithburgh jetty
are exceptional diverse and support a host of
sessile organisms with at least 30 sponge
species, 10 bryozoan species, 20 colonial
ascidian species, 9 solitary sea squirt species,
9 tube-building polychaete worm species and
4 barnacle species recorded (Butler 1982).
2.5
−
European
Shipwrecks
−
The majority of shipwrecks in this
region are associated with Troubridge
Shoals, which are regarded as very
dangerous waters for navigation and
diving. The `Iron King’ on
Troubridge Shoals is a popular dive
spot, but is very broken up and prone
to strong currents.
−
`Zanoni’ (1865-1867): a 139 foot three-masted
composite barque of iron frames and wood
planking which sank in a freak storm off
Ardrossan. There is a protected zone declared
around the `Zanoni’. The `Zanoni’ is a
designated Historic Shipwreck under the SA
Historic Shipwreck Act 1981. The wreck lies
in 18m of water approximately 20 nautical
miles north west of Port Adelaide. The depth
of water, lack of surge and lack of oxygen and
light and no salvage are the main factors that
leave the `Zanoni’ in good condition.
3
CURRENT CONSERVATION STATUS
OF THE ORONTES BIOUNIT
Adjacent Land Use
National and Conservation Parks
Troubridge Island Conservation Park (314 ha).
Agriculture/Industry
−
Most adjacent land in this biounit is
agricultural.
−
Ardrossan is a deep sea port, shipping bulk
grain from the peninsula. There is also a
nearby dolomite quarry owned by BHP.
Crushed rock for this operation is shipped
from Ardrossan.
−
Ardrossan, Edithburgh and Port Vincent have
permanent coastal mooring facilities for
commercial and recreational craft.
Urban Centres
−
−
Marine Reserves
None
−
Marine Parks
None
Ardrossan (population 963).
−
Stansbury (population 520).
−
Edithburgh (population 400).
−
Port Vincent (population <250).
2.6
Features
−
Significant Cultural and Historical
−
In addition to this total closure, nets are
prohibited in waters exceeding 5 metres in
depth contained within a line from Sultana
Point to Marion Reef buoy, then to Troubridge
Island lighthouse and then to a point adjacent
to Giles Point.
−
Coobowie (all waters within a line from the
Salt Swamp Creek causeway to the end of the
old Coobowie jetty structure and then to
Hickies Point).
Aboriginal
−
Black Point is considered to
considerable cultural importance.
be
Netting Closures
Edithburgh (all waters south west of a line from
Sultana Point to a point on the mainland
adjacent to the roadway between sections 185
and 205 Hd Melville.
of
Page 170
GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – ORONTES BIOUNIT
−
4
Stansbury ( all waters west of a line from the
groyne at Oyster Point to a point 200 metres
north of the jetty and then south westerly to a
point on the mainland 200 metres north of the
jetty).
Black Point
−
AREAS OF HIGH CONSERVATION
VALUE IN THE ORONTES BIOUNIT
Salt Creek Bay 35
−
Prime IUCN Conservation Values: research,
biodiversity, education, social values (IUCN
Category IA). IUCN Identification Criteria:
naturalness (not subjected to human-induced
change), biogeographic (`Orontes Bank', Giles
Point `geological monument'), ecological,
(range of coastal wetland habitats, extensive
seagrass meadows, major fisheries nursery and
feeding area - King George Whiting, Garfish,
Western King Prawn, Port Jackson Shark
spawning area), economic (marine scalefish
fisheries,
tourism),
social
(education,
recreation, artificial reef-Giles Point, diving,
yachting), scientific (University of Adelaide
Coobowie Research Station, Edithburgh jetty),
national (potential for listing on the Register of
the National Estate), practicality (accessibility,
compatibility).
Prime IUCN Conservation Values: cultural
values, biodiversity (IUCN Category III).
IUCN Identification Criteria: biogeographic
(geological monument-Port Julia), ecological
(seagrass meadows, major nursery and feeding
areas - King George Whiting, Garfish, Western
King Prawn, Blue Swimming Crab), economic
(marine scalefish fisheries, Western King
Prawn,
tourism),
social
(aboriginal
significance-Black Point, recreation, yachting).
Tiddy Widdy
−
Prime IUCN Conservation Values: cultural
values, biodiversity (IUCN Category III).
IUCN Identification Criteria: biogeographic
(representative marine habitats), ecological
(wetland habitats - mangroves, seagrass
meadows, major nursery and feeding areas King George Whiting, Garfish, Western King
Prawn, Blue Swimming Crab), economic
(marine scalefish fisheries, Western King
Prawn,
tourism),
social
(aboriginal
significance-Tiddy Widdy, recreation, yachting).
Oyster Bay-Port Vincent
−
Prime IUCN Conservation Values: education,
biodiversity, social values (IUCN Category IA).
IUCN Identification Criteria: naturalness (not
subjected
to
human-induced
change),
biogeographic (`Orontes Bank', geological
monuments-Stansbury-Port
Vincent,
Port
Vincent), ecological, (range of marine habitats,
seagrass meadows, major fisheries nursery area
- King George Whiting, Garfish, Western King
Prawn), economic (marine scalefish fisheries,
Western King Prawn, tourism), social
(education-Port Vincent Primary School and
Aquatic Centre, recreation, diving, yachting),
practicality (accessibility, compatibility).
35
Salt Creek Bay was nominated for declaration as an Aquatic
Reserve by the former South Australian Department of Fisheries in
1974, for marine educational purposes (Wynne 1980).
Page 171
GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – CLINTON BIOUNIT
XXI
MARINE BIOGEOGRAPHY AND CONSERVATION VALUES OF THE
CLINTON BIOUNIT
This biounit extends from Ardrossan on the eastern side of Yorke Peninsula to Marino Rocks (just north of Hallet
Cove, metropolitan Adelaide). It includes the upper reaches or `head' of Gulf St Vincent and covers an area of
249,136 ha and a coastal distance of approximately 185 km.
MARINE BIOGEOGRAPHY
3
BIOLOGY
Major Inshore Habitats
1
OCEANOGRAPHY
−
Major intertidal habitats in the region include
tidal wetlands (ie. mangrove, coastal
saltmarshes, tidal mudflats), sandy beaches
and some low rocky shores.
−
Of the total inshore subtidal habitats mapped
in the biounit (157,029 ha), seagrass meadows
comprise 132,576 ha (84.4%), sandy bottoms
comprise 21,173 ha (13.5%), and reefs
comprise 3,280 ha (2.1%).
This region is one of very low wave energies at the
`head' of the Gulf, gradually increasing to moderate
at Outer Harbour and Marino Rocks.
2
GEOLOGY
AND
GEOMORPHOLOGY 36
COASTAL
North of Ardrossan the cliffs finish and are
replaced by a long beach area with small dunes at
Tiddy Widdy Beach. These sandy beaches give
way to muddy tidal flats at Price and then to
mangrove flats at Clinton. Wide mangrove tidal
flats continue relatively unbroken to Sandy Point.
From Sandy Point to Middle Beach, the mangroves
are gone and replaced by wide tidal flats. The
mangrove flats begin again at Middle Beach and
continue in a southerly direction until Torrens
Island, near Outer Harbour.
From Outer Harbour southwards to Marino Rocks,
there is a 30 km sandy beach composed largely of
silica sand (an unusual feature for beaches in South
Australia as most are calcium carbonate) fronting
an extensive plain. Originally backed by a multiple
foredune system, the beach is now largely built
upon or has been removed. There is a gentle
offshore gradient from the coast which was
originally well covered by seagrass meadows but
has now been severely degraded due to effluent and
stormwater discharge.
Major Benthic Communities
•
Macroalgal
−
There are no significant reefal communities in
this northern section of this biounit.
•
Seagrasses
−
This region is dominated by extensive
seagrass meadows and tidal flats. Sandy
sediments are commonly colonised by species
of Posidonia (P.sinuosa, P.angustifolia) and
Halophila australis, which often occurs
adjacent to reef communities and in deep
water (ie. 20m). In these deeper water parts
of the gulf, the soft sediments are dominated
by faunal assemblages, such as bivalve
molluscs (ie. scallops, Pinna bicolor),
bryozoans, ascidians and holothurians.
Coastal and Offshore Islands (or Reefs)
−
None.
36
From Yorke Coast Protection District Study Report (Wynne
1980).
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GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – CLINTON BIOUNIT
Other substantial communities occur in lower
Spencer Gulf (6,000ha), on the west coast of
Eyre Peninsula (9,000 ha) and on Kangaroo
Island (7,000 ha) (DELM 1993). In Gulf St
Vincent, mangroves, and associated coastal
saltmarshes, seagrasses and tidal mudflats
dominate the upper portion of the Gulf from
Port Clinton to Port Adelaide.
Rivers and Estuaries
−
Wakefield River.
−
Light River.
−
Gawler River.
−
Chapman Creek.
−
Port Adelaide River - Barker Inlet estuary.
−
Torrens River (which flows out to sea at
Henley Beach).
−
Brown Hill and Sturt Creeks (which drain into
the Patawalonga at Glenelg which then flows
into the sea).
•
−
Extensive Seagrass Meadows
This biounit contains the largest areas of
seagrass meadows in Gulf St Vincent, and the
second largest in South Australia. Gulf St
Vincent (along with Spencer Gulf) contain
some of the most extensive areas of temperate
seagrass meadows in Australia (Edyvane
1996). These extensive seagrass meadows
flourish in the shallow waters of the gulf,
generally in waters less than 15m, and provide
the basis for the significant productivity of the
gulf in terms of fisheries and prawn
production. Seagrasses cover approximately
2,436 km2 in Gulf St Vincent, and represent
25% of the total area of seagrasses recorded in
South Australia (ie. 9,612 km2). Most of the
seagrasses in the gulf are located in the
northern reaches of the gulf (ie. Clinton
Biounit, 132,576 ha), in the Orontes Bank
region along the eastern coast of Yorke
Peninsula (ie. Orontes Biounit 51 713 ha), and
along the southern coast of Yorke Peninsula in
Investigator Strait (Sturt Biounit, 23,229 ha).
−
The extensive coastal and marine wetlands in
this biounit have been conserved in several
conservation areas: Clinton Conservation
Park, Port Gawler Conservation Park, Barker
Inlet Aquatic Reserve and the St Kilda Chapman Creek Aquatic Reserve.
−
Wills Creek has been identified as a wetland
of national importance (see ANCA 1996).
The area consists of an extensive, shallow,
mangrove tidal estuary, comprising two creeks
(Wills Creek and Shag Creek). The wetland
provides habitat for migratory waders and is a
major site of cormorant breeding activity on
the Yorke Peninsula. Threatened species of
waterbirds include the Eastern Curlew,
Numenius madagascariensis (Sv), Musk
Duck, Biziura lobata (Sv), Fairy Tern, Sterna
nereis
(Sv),
Slender-billed
Thornbill,
Acanthiza iredalei rosinae (Sv), and Whitebellied Sea-Eagle, Haliaeetus leucogaster
(Sv). A total of 49 species of waterbirds have
been recorded for the area: 18 listed under
international treaties.
MARINE CONSERVATION VALUES
1
1.1
SIGNIFICANT
BIOLOGICAL
PHYSICAL FEATURES
AND
Biological
Coastal and Marine Wetlands of National
Importance
•
−
Extensive Mangrove and Tidal Wetlands.
This biounit contains the largest areas of tidal
wetlands and mangroves in Gulf St Vincent,
and the second largest in South Australia.
Gulf St Vincent (along with Spencer Gulf)
contains some of the most extensive areas of
mangrove forests and tidal wetlands in South
Australia (and the largest areas of temperate
mangroves in Australia) (Edyvane 1996).
Associated with the mangrove habitats are the
biologically rich mud flats, coastal saltmarshes
and seagrasses. Together, these communities
provide key habitats for waterfowl and waders
(Close & McCrie 1986), and important
feeding, breeding and nursery areas for
economically important species of fish and
crustaceans (eg. Western King Prawn, King
George Whiting, Southern Sea Garfish).
Mangrove and saltmarsh communities along
the South Australian coast total approximately
82 000 ha, with the largest communities
occurring in Spencer Gulf (46,000 ha) and
Gulf St Vincent (20,000 ha).
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GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – CLINTON BIOUNIT
Species of waterbirds which breed in the area
include all 4 species of cormorants, Great
Cormorant, Phalacrocorax carbo, Little Black
Cormorant,
P.sulcirostris,
large
Pied
Cormorant, P.varius (over 1000 pairs) and
Little Pied Cormorant, P.melanoleucos. The
nearby saltfields at Price have been identified
as an area of international importance for
shorebirds by Watkins (1993). The estuary
also provides a significant nursery area for
wide range of fish and crustaceans, including
Yellow-eye Mullet, Tommy Ruff, Southern
Sea Garfish, King George Whiting, School
Whiting, and Southern Fiddler Ray.
The
Department of Environment, Heritage and
Aboriginal Affairs is in the process of
proclaiming the area as a Conservation Park.
−
−
Clinton has been identified as a wetland of
national importance (see ANCA 1996).
Clinton
Conservation
Park
is
a
mangrove/samphire estuary with subtidal
seagrass meadows, and many large tidal
channels, fringed by mangroves. The River
Wakefield is the only major drainage channel
in the area. The extensive tidal channels are
important habitats for birds and marine fauna,
particularly fish and crustaceans. The area has
been identified as an area of international
importance for shorebirds by Watkins (1993).
Threatened species of waterbirds in the area
include the Eastern Curlew, Numenius
madagascariensis (Sv), Fairy Tern, Sterna
nereis (Sv), and part of the limited habitat of
the Slender-billed Thornbill, Acanthiza
iredalei rosinae (Sv). A total of 38 species of
waterbirds have been recorded in the area: 11
are listed under international treaties. The
Clinton Conservation Park is listed on the
Register of the National Estate.
Port Gawler and Buckland Park lake have
been identified as a wetland of national
importance (see ANCA 1996). Port Gawler
consists of vast tidal flats and fringing
mangrove forests, dissected by a multitude of
tidal channels, creeks and the Gawler River.
Port Gawler Conservation Park (434 ha) is a
mangrove/samphire estuarine area with many
large tidal channels fringed by mangroves.
Port Gawler provides an important nursery
area for commercial fish and crustacean
species. A total of 13 species of marine fish
have been recorded. Buckland Park lake is a
large, ephemeral freshwater lake which was
formed by damming the deltaic mouth of the
Gawler River. The lake attracts an extremely
wide variety of waterbirds, particularly
waterfowl, that use the lake and associated
swamps for feeding, breeding and roosting.
The lake is the only substantial freshwater
habitat on the Adelaide Plains and is also the
single most important breeding habitat for
waterfowl within the Adelaide region.
Threatened species in the area include the
saltmarsh plant, Halosarcia flabelliformis (Nv,
Sv) and the following species of waterbirds:
White-bellied
Sea-Eagle,
Haliaeetus
leucogaster (Sv), Cape Barren Goose,
Cereopsis novaehollandiae (Sv), Freckled
Duck, Stictonetta naevosa (Sv), Musk Duck,
Biziura lobata (Sv), Little Egret, Egretta
garzetta (Sv), Eastern Curlew, Numenius
madagascariensis (Sv), Fairy Tern, Sterna
nereis
(Sv),
Slender-billed
Thornbill,
Acanthiza iredalei rosinae (Sv), Australasian
Shoveler, Anas rhynchotis (Sr), Baillon’s
Crake, Porzana pusilla (Sr) and Spotless
Crake, Porzana tabuensis (Sr). A total of 65
waterbirds have been recorded in the area: 16
are listed under international treaties. At Port
Gawler there are well-established nesting
colonies of Pied Cormorants, Phalacrocorax
varius. Port Gawler is listed on the Register of
the National Estate.
−
The coastal and marine wetlands of Barker
Inlet and St Kilda (on the eastern shore of
Gulf St Vincent) have been identified as
wetlands of national importance (see ANCA
1996). The region encompasses the coastal
waters, fringing mangroves, tidal creeks and
adjoining wetlands and saltfields of the Barker
Inlet, extending from St Kilda to Outer
Harbour. The wetlands in the region are
conserved in two aquatic reserves: the Barker
Inlet – St Kilda Aquatic Reserve and the St
Kilda - Chapman Creek Aquatic Reserve.
Barker Inlet itself comprises the extensive
coastal estuary of the Port Adelaide River,
with two islands (Torrens Island, Garden
Island). The inlet is dissected by several tidal
and freshwater (and stormwater) creeks which
drain into the eastern side of the inlet, ie.
Swan Alley Creek (from the Little Para
River), Chapman Creek, Broad Creek and
North Arm Creek. The wetlands in the region
represent the largest area of mangrove forests
in Gulf St Vincent (Edyvane 1991) and a good
example of coastal and marine wetlands in
Gulf St Vincent, and is one of the few
examples in close proximity to a major city in
Australia.
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GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – CLINTON BIOUNIT
The extensive coastal tidal floodplain in the
region encompasses several major coastal
habitat types include low-lying dunes and
chenier ridges, supratidal samphire flats
(which are covered by extremely high spring
tides),
intertidal
mangrove
woodlands
(dominated by Avicennia marina); intertidal
mud and sand flats, tidal channels and subtidal
seagrass meadows (dominated by Eelgrass,
Zostera muelleri and Garweed, Heterozostera
tasmanica and Tapeweed, Posidonia). St
Kilda - Chapman Creek Aquatic Reserve abuts
the Barker Inlet Aquatic Reserve and
predominantly protects the intertidal habitats
from St Kilda to Chapman Creek. It is an
important extension of the Barker Inlet habitat
and has similar biological features. The variety
of coastal habitats provide roosting, sheltering
and feeding grounds for a large number of
waterbirds and provide early spring to late
summer refuge for many migratory waders
(ANCA 1996). Threatened species in the area
include the saltmarsh plants, Halosarcia
flabelliformis (Nv, Sv) and Centrolepis
cephaloformis (Sr) and 3 species of waterbirds:
White-bellied
Sea-Eagle,
Haliaeetus
leucogaster (Sv), Little Egret, Egretta garzetta
(Sv), Slender-billed Thornbill, Acanthiza
iredalei rosinae (Sv). A total of 57 species of
waterbirds have been recorded in the area: 12
are listed under international treaties. The area
also provides significant breeding habitats for
18 species of waterbirds including, pelicans,
cormorants, oystercatchers, gulls, terns, egrets
and herons. The Port River mouth and the
Penrice saltfields have been identified as areas
of international importance for shorebirds by
Watkins (1993). The inlet and adjoining
mangrove creeks serve as important nursery
areas for a number of commercial and
recreationally important species of fish and
crustaceans (see below), and are recognised
feeding areas for the Common Dolphin,
Delphinus delphis. Other marine mammals
recorded in the region include the Leopard
Seal, Hydrurga leptonyx,
Blue Whale,
Balaenopter musculus (Ne, Se) and Shortfinned
Pilot
Whale,
Globicephala
macrorhyncus (Sr) (ANCA 1996).
−
meadows in the region make a significant
contribution to the primary production of the
inlet. The algae and discarded seagrass leaves
are a further component in the food web of the
inlet. At high tide many fish, eg. Garfish,
Whiting, Flounder and Mullet, may be
observed feeding on polychaete worms, small
crustaceans and molluscs on these intertidal
flats while at low tide many wading birds are
seen feeding in these same areas. The
intertidal mudflats are an important
decomposition area and the site of extensive
detritus-based (drifting/decomposing plant
matter) food chain. This is evident by the
many worm mounds and crabs that may be
observed feeding on the mudflats. At high
tides these flats are important feeding areas for
such fish species as Garfish, Flounder and
Mullet. The narrow subtidal band of
Tapeweed (Posidonia sp.) along the edge of
the Barker Inlet channel provides shelter and
food for many organisms.
Other Areas of Recognised Conservation
Significance
−
The Light River Delta is unique in this region
as it has closely associated salt and freshwater
wetland ecology. It is very rich in bird life
and in plant species. It is a seasonal wetland.
−
Seacliff reef is widely recognised as one of
best local dive spots in Adelaide, due to its
abundance of fish and relatively shallow depth
(Diving Industry Association of South
Australia).
Seacliff reef is a remnant
shoreline, which runs parallel to the coast in a
north-south direction, in 12-15m of water.
The reef is home to a wide variety of marine
life, particularly fish, including Leafy Sea
Dragons and the greatest number of Blue
Devils in the metropolitan area. The reef is
listed as one of the best dive spots in South
Australia, in `Dive South Australia: The Best
Dive Sites in South Australia’ (Diving
Industry Association of South Australia).
The Barker Inlet estuary represents the most
significant nursery area for many species of
important commercial and recreational marine
fish species in Gulf St Vincent including
Western King Prawns (Penaeus latisulcatus),
King
George
Whiting
(Sillaginodes
punctatus), Yellow-Fin Whiting (Sillago
schomburgkii),
Garfish
(Hyporhamphus
melanochir), Yellow-Eye Mullet (Aldrichetta
fosteri), Jumping Mullet (Liza argentea),
Bream (Acanthopagrus butcheri) and Blue
Swimming Crabs (Portunus pelagicus) (Jones
1984, McGlennon 1992). These seagrass
Page 175
GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – CLINTON BIOUNIT
1.2
Physical
Geological Monuments
−
2
2.1
Pine Point (from carpark north for 1 km):
shore platform and cliffs. Significant features
include an unconformity and Pre-Tertiary
faulting. Pine Point Quarry is on the Register
of the National Estate.
The marine scalefish catch for this region (ie.
Fishing Zones 35 and 36) represented 832,099 kg
in 1995/96 and 692,894 kg in 1996/97(or 8.00%
and 6.84% of the total catch for the marine
scalefish fishery in South Australian waters).
Although license holders are not restricted to
fishing in this biounit, the following licenses are
registered in this area:
−
Port Adelaide 37: 1 Abalone, 9 Gulf St Vincent
Western King Prawn, 2 Southern Rock
Lobster, 6 Spencer Gulf Western King Prawn,
5 Southern Rock Lobster, experimental crab 1,
1 West Coast Prawn, 1 Abalone, 10 restricted
marine scalefish
−
Port Clinton: 1 restricted marine scalefish, 3
unrestricted marine scalefish
−
Port Gawler: 1 restricted marine scalefish
−
Port Price: 1 restricted marine scalefish, 1
unrestricted marine scalefish
−
Port Wakefield: 2 restricted marine scalefish,
12 unrestricted marine scalefish
−
Port Parham: 1 unrestricted marine scalefish
−
Pine Point: 3 unrestricted marine scalefish
OTHER VALUES
Commercial Fisheries
The main single species fishery in this biounit is
the Western King Prawn. Trawling in the gulf
begins from just south of Port Prime to the north
east tip of Kangaroo Island. Trawling does not
occur north of Ardrossan or Port Prime. The
biounit is also one of the most significant fishing
grounds for the marine scalefish industry in South
Australia. There is no commercial harvesting of
abalone in this biounit.
Western King Prawn
This biounit is located within the waters of the Gulf
St Vincent prawn fishery, which comprises 10
license holders (ie. boats). All vessels fish within
the waters of the Gulf St Vincent and Investigator
Strait biounits (ie. Sturt, Investigator, Orontes,
Clinton, Yankalilla, Nepean, Encounter, St
Vincent). In 1995/96 and 1996/97 a total of
258,459 and 210,581 kg was caught for this
fishery, with a total effort of 2,996 and 3,235 hours,
respectively (or 11.38% and 10.41% of the total
catch for Western King Prawn in South Australian
waters).
2.2
There is currently no aquaculture in this region.
The Gulf St Vincent/Fleurieu Aquaculture
Management Plan (Berggy 1996) proposes limited
aquaculture development in this region:
Marine Scalefish Fisheries
The Clinton Biounit represents a significant region
for the marine scalefish industry in South Australia
and comprises 2 major fishing zones: Fishing Zone
35 (northern waters) and 36 (southern waters).
During 1995/96 and 1996/97, 135 and 102
commercial licence holders (made up of Marine
Scalefish and Restricted Marine Scalefish licence
categories) caught commercial marine scalefish
species from this region (ie. Fishing Zones 35 and
36), respectively.
License holders expended a
total of 9065 and 7254 boat days effort fishing
these waters during 1995/96 and 1996/97,
respectively.
Aquaculture
Upper Gulf St Vincent Policy Area
−
Upper Gulf North Management Zone
(northern gulf waters, from Tiddy Widdy
Beach to just north of Middle Beach) – zoned
for
limited
aquaculture
development.
Licenses will be considered for a total of 40ha
of algal culture in this zone. Licenses for
other forms of aquaculture will not be
considered.
37
Abalone and southern rock lobster are not caught in this
bioregion - Port Adelaide is the registered home address for these
licenses only.
Page 176
GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – CLINTON BIOUNIT
−
−
Upper Gulf South Zone (southeastern gulf
waters, from just north of Middle Beach to
Outer Harbour) – zoned for recreational,
fishing, and conservation values. Licenses
will not be considered for aquaculture
development in this zone.
Upper Gulf Management Zone (waters
offshore from Port Gawler) – zoned for
subtidal aquaculture development. Licenses
will be considered for a total of 40ha of
aquaculture development in this zone,
excluding the culture of Pacific Oysters.
Tourism
−
Canoeing, dolphin education and ecointeraction tours of the Port River and Barker
Inlet estuary.
−
The Barker Inlet estuary is a very popular area
for recreational activities including fishing,
boating, power boat racing, canoeing, water
skiing and bird watching.
−
SCUBA diving: there are several popular
wreck and reef dive sites in the metropolitan
Adelaide region, including the Glenelg dredge
(5-6kms west of Glenelg), Glenelg barge
(5kms west of Glenelg), Glenelg tyre reef
(5kms west of Glenelg), Macs Ground (reef
4.5kms west of Glenelg), Milkies reef (reef
4.5kms south west of Glenelg), Seacliff reef,
`Leather Jacket Alley’ (2kms north west of
Glenelg), `Broken Bottom’ (low reef 2kms
north west of Glenelg), Grange tyre reef
(4kms west of West Beach), `Norma’
shipwreck (4kms west of North Haven), `John
Robb’ shipwreck (15kms west of North
Haven). All are recognised dive spots and are
listed in `Dive South Australia: The Best Dive
Sites in South Australia’ (Diving Industry
Association of South Australia).
Metropolitan Adelaide Policy Area
−
Metropolitan Inshore Management Zone
(inshore waters, within 2nm of the coast, from
Outer Harbour to Sellicks Beach) – zoned for
Blue Mussel spat collection. Licenses will be
considered for a total of 10ha of Blue Mussel
spat collection. Licenses for other forms of
aquaculture will not be considered.
−
Metropolitan Offshore Management Zone
(offshore waters, from 2nm to offshore
boundary of policy area, from Outer Harbour
to Sellicks Beach) – zoned for aquaculture
development. Licenses will be considered for
a total of 60ha of bivalve aquaculture (early
growth stages). Licenses for other forms of
aquaculture will not be considered.
2.3
Recreation and Tourism
2.4
−
At St Kilda there is mangrove 1.7 km board
walk and education/interpretative centre that is
very popular with schools and universities. It
is managed by the Salisbury City Council,
with assistance from the SA National Parks
and Wildlife Service.
−
Barker Inlet is a popular area for research into
pollution, mangroves and fish ecology.
Institutions that have used this area include the
South Australian Department of Fisheries, The
Flinders University of South Australia and
The University of Adelaide, the Electricity
Trust of South Australia, and the Engineering
and Water Supply Department.
−
The Barker Inlet – St Kilda and adjacent salt
fields region is a very popular region for bird
watching and is regularly visited by overseas
ornithologists and has become a bird
observation area of interstate and international
reknown (ANCA 1996).
Fishing
−
−
−
Price: boat and jetty fishing. Major species:
King George Whiting, Yellowfin Whiting,
Black Bream, Sand Flathead, Yelloweye
Mullet,
Australian
Salmon,
Snapper,
Mulloway, Snook, Garfish, Blue Swimming
Crab, Tommy Rough and Southern Calamari.
St Kilda: boat and shore fishing. Major
species: King George Whiting, Yellowfin
Whiting, Black Bream, Sand Flathead,
Yelloweye Mullet, Snapper, Mulloway,
Snook, Garfish, Blue Swimming Crab,
Tommy Rough and Southern Calamari.
Port Adelaide River: boat and shore fishing.
Major species: King George Whiting,
Yellowfin Whiting, Black Bream, Sand
Flathead, Australian Salmon, Yelloweye
Mullet, Snapper, Mulloway, Snook, Garfish,
Blue Swimming Crab, Tommy Rough.
Scientific Research and Education
Page 177
GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – CLINTON BIOUNIT
−
2.5
The Star-of-the-Sea Primary School and
Aquatic Centre, at Henley Beach, provides a
range of school-based marine and coastal
educational activities in the metropolitan
Adelaide region. The centre offers a range of
courses and educational activities on marine
and coastal habitats and species, utilising the
local environments of metropolitan Adelaide,
and also hosts a wide range of marine aquaria
for project work.
Adjacent Land Use
National and Conservation Parks
−
Clinton Conservation Park (1,951 ha) (Martin
1980).
−
Port Gawler Conservation Park (418 ha)
(SANPWS 1983).
−
Torrens Island Conservation Park (79 ha).
−
Fort Glanville Conservation Park (4 ha): a
historical conservation park associated with
European settlement.
Due to its close proximity to Adelaide, there are
also several industries located on land immediately
adjacent to the wetlands of the Barker Inlet estuary
and the Port Adelaide River. A number of these
industries discharge directly into adjacent waters.
Major pollution inputs include, the Torrens Island
Power Station, which discharges warm water into
Barker Inlet, and the Port Adelaide Sewage
Treatment Works, which discharges secondarily
treated effluent into the Port Adelaide River.
Further, this area also receives pollution from the
Little Para River and `urban runoff’ from several
stormwater drains which discharge into the estuary.
Together, these pollutant inputs have resulted in the
Port River estuary being one of the most diversely
polluted estuaries in South Australia (Edyvane
1996). In recent years, the establishment of the
Multi-Function Polis in the region, at Gillman and
Dry Creek has seen the development of man-made
wetland areas using stormwater runoff from
adjacent areas.
Klein Point is quarried for Tertiary limestone used
in cement manufacture which is shipped to Port
Adelaide.
Urban Centres
−
Port Wakefield (population <250).
Port
Wakefield has a permanent coastal mooring
facility for commercial and recreational craft.
−
Adelaide and its suburbs (population expected
to be between 1.13 and 1.17 million by the
turn of the century).
Agriculture/Industry
Much of the adjacent coastal land in this biounit is
covered by coastal wetlands (ie. mangrove swamps
and samphire flats). As such, there is generally
little agricultural activity which occurs immediately
adjacent to the coast. Despite this, considerable
reclamation activity has occurred in this region,
particularly for salt production. Extensive salt
fields owned by Penrice Soda Products Pty Ltd
occur adjacent to the mangroves and wetlands in
the Barker Inlet-Port Gawler region.
Salt
production also occurs adjacent to mangroves at
Port Price.
The southern part of this biounit is occupied by the
city of Adelaide, the largest centre of population in
South Australia. Along the coastal metropolitan
Adelaide region, 4 sewage treatment works
discharge secondarily treated effluent into coastal
waters (ie. Bolivar, Port Adelaide, Glenelg,
Christies Beach). The Bolivar Sewerage Treatment
Works is located north of metropolitan Adelaide
(south of Port Gawler) and discharges secondarily
treated effluent and sludge. In addition a number
of diffuse sources of marine pollution occur via
stormwater inputs from the Torrens River (which
flows out to sea at Henley Beach) and Brown Hill
and Sturt Creeks (which drain into the Patawalonga
at Glenelg, which then flows into the sea).
Other Uses
Permanent coastal mooring facilities for
commercial and recreational craft at St Kilda,
Garden Island, North Arm, North Haven, Port
Adelaide and environs and Patawalonga (Glenelg).
−
Department of Defence Firing Range near Port
Parham. This is an area of prohibited public
access (for both land, and sea).
−
Outer Harbour and Port Adelaide are major
ports for international and national ships.
Page 178
GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – CLINTON BIOUNIT
2.6
Features
Significant Cultural and Historical
−
`John Robb’ - the wreck sank during a storm
in the outer shipping channel to Outer Harbour
in 1910.
The wreck is nearly completely
broken up (apart from the bow) and is located
15kms west of North Haven in 18m of water.
−
`Grecian’ (1841-1850): a three-masted
wooden barque which was wrecked in a storm
at the entrance to Outer Harbour with the loss
of one life.
3
CURRENT CONSERVATION STATUS
OF THE CLINTON BIOUNIT
Aboriginal
−
Tiddy Widdy beach (has been looted).
European
Shipwrecks
−
−
−
−
−
`Santiago’ (1856-1945): a three-masted iron
barque, abandoned in the North Arm of the
Port River.
There are several wrecks and artificial reefs in
the metropolitan Adelaide region which are
also popular dive spots:
Glenelg dredge - is an old suction dredge built
in Holland in 1914 and sailed out to Australia
in 1920. The dredge was used to dredge the
Port River and Outer Harbour and was sunk in
1985 as an artificial reef. The wreck is located
5-6kms west of Glenelg in 20m of water.
Glenelg barge - is a hopper barge used by the
Glenelg dredge to take the silt dredged from
the Port River. The barge was sunk in 1984
as an artificial reef. The wreck is located
5kms west of Glenelg in 20m of water.
Glenelg tyre reef – is a reef composed of tyre
tetrahedrons which was established in 1983.
The artificial reef is located 500m south east
of the Glenelg barge, 5kms west of Glenelg, in
18m of water.
−
Grange tyre reef - is a reef composed of tyre
tetrahedrons which was established in the late
1970s. The artificial reef is located 4kms west
of West Beach in 15m of water.
−
`Norma’ (1898-1907): a four-masted steel
barque which was sunk by a collision with the
`Ardencraig’ with the loss of one life in the
main shipping channel of Outer Harbour in the
early 1900s. As a shipping hazard the wreck
was blown up by authorities, but the bow is
still recognisable. The wreck is located 4kms
west of North Haven in 16m of water.
−
−
Marine Reserves
St Kilda-Chapman Creek (870 ha)
Barker Inlet-St Kilda (2,055 ha)
−
Marine Parks
None
−
Netting Closures
Price (within 1.1 nautical mile radius of Will
Creek Light Beacon north of Mangrove Point
and all waters of Will Creek and its
tributaries).
−
Port Wakefield (within 100 metres of the
dredged channel extending generally in a
south-westerly direction from the mouth of the
River Wakefield).
−
Outer Harbour and Port Adelaide River (those
waters bounded by southern and northern
revetment mounds at Outer Harbour including
those enclosed by a line from the north eastern
end of the northern revetment mound to the
Section Bank pile beacon (Black Pole), to the
Middle Ground outer beacon, to Point Grey on
the northern tip of Torrens Island, then
generally in a southerly direction contiguous
with the western extremity of the mangroves
on Torrens Island which includes all the
waters of the Port Adelaide River and the
North Arm as far as the Grand Trunkway
Road Bridge.
−
Metropolitan beaches (all waters of Gulf Saint
Vincent within 600 metres of high water mark
between the seaward end of the southernmost
Outer Harbour breakwater and the southern
boundary of the Aldinga Aquatic Reserve.
−
Patawalonga Lake (all waters of the lake).
Page 179
GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – CLINTON BIOUNIT
4
AREAS OF HIGH CONSERVATION
VALUE IN THE CLINTON BIOUNIT
`Zanoni' Shipwreck
−
Light River - Port River Estuary 39
−
Prime IUCN Conservation Values: cultural
values, biodiversity (IUCN Category III). IUCN
Identification Criteria: naturalness (not
subjected to human-induced change), ecological
(range of marine habitats-reefs, seagrass
meadows, significant reef fish populations),
economic (marine scalefish fisheries, tourism),
social (cultural-shipwreck, shipwreck diving),
practicality (insulation, compatibility-Historic
Shipwreck).
Wills Creek-Clinton Conservation Park 38
−
Prime
IUCN
Conservation
Values:
biodiversity, aesthetics, rare and endangered
species/habitats, social values (IUCN Category
IB).
IUCN Identification Criteria:
naturalness (not subjected to human-induced
change), biogeographic (representative marine
habitats, most significant nursery in Gulf St
Vincent for Western King Prawn, geological
monument-Port Julia), ecological, (wide range
of coastal marine wetlands and habitatsextensive seagrass meadows and mangrove
forests, estuaries-Wills Creek, Shag Creek,
Wakefield River, major nursery area and
feeding area for fisheries in Gulf St VincentKing George Whiting, Garfish, Western King
Prawn,
Yellow-Eye
Mullet,
threatened
waterbirds-Eastern Curlew, Fairy Tern, Whitebellied Sea-Eagle, breeding colonies of Pied
Cormorants, Great Cormorants, Little Black
Cormorants, Little Pied Cormorants, Little
Terns, Caspian Terns), economic (marine
scalefish fisheries, Western King Prawn,
tourism), social (aesthetic values, recreation),
national/international (international importance
for shorebirds, Wetlands of National
Importance-Wills Creek, Clinton Conservation
Park, Register of the National Estate-Clinton
Conservation Park, potential for listing as a
RAMSAR site), practicality (insulation,
accessibility, compatibility-adjacent to Wills
Creek wetland, Clinton Conservation Park).
Prime
IUCN
Conservation
Values:
biodiversity, education, social values, rare and
endangered species/habitats (IUCN Category
II).
IUCN Identification Criteria:
biogeographic (`geological monument', most
extensive marine wetlands in Gulf St Vincent),
ecological, (wide range of coastal marine
wetlands and habitats, extensive and diverse
coastal saltmarsh flats, estuaries-Light River,
Gawler River, Chapman Creek, Port River,
most significant fisheries nursery and feeding
area in entire gulf-King George Whiting,
Garfish, Yellow-fin Whiting, Yellow-Eye Mullet,
Jumping Mullet, Bream, Blue Swimming Crab,
most extensive mangrove forests and seagrass
meadows in Gulf St Vincent, threatened
waterbirds-White-bellied Sea Eagle, Cape
Barren Goose, Little Egret, Fairy Tern,
breeding colonies of Pied Cormorants, Caspian
Terns, Australian Pelicans), economic (marine
scalefish fisheries, Western King Prawn,
tourism), social (education-St Kilda Mangrove
Trail
Interpretation
Centre,
extensive
recreation, historic shipwrecks- `Santiago’,
`Norma’, `John Robb’, `Grecian’'), scientific
(fisheries research/monitoring-Barker Inlet),
national (Wetlands of National Importance-Port
Gawler and Buckland Park, Barker Inlet and St
Kilda, Register of National Estate-Port Gawler
Conservation Park, Conservation Park),
practicality
(insulation,
accessibility,
compatibility-adjacent
to
Port
Gawler
Conservation
Park,
Torrens
Island
Conservation Park, St Kilda-Chapman Creek
Aquatic Reserve, Barker Inlet Aquatic Reserve).
Glenelg Shipwrecks
Prime IUCN Conservation Values: cultural
values, biodiversity (IUCN Category III).
IUCN Identification Criteria: ecological
(seagrass meadows, significant reef fish
populations), economic (marine scalefish
fisheries, tourism), social (shipwrecks-Glenelg
dredge, Glenelg barge, shipwreck diving),
practicality (insulation, compatibility-Historic
Shipwreck).
39
38
Mangrove areas between Port Clinton to Port Wakefield were
nominated for declaration as Aquatic Reserves by the former South
Australian Department of Fisheries in 1974, for fisheries
management and conservation purposes (Wynne 1980).
The region from Port Prime, south to, and including, Torrens
Island, and also, the St Kilda-Chapman Creek and Barker Inlet
Aquatic Reserves, is presently the subject of a multiple-use Marine
Protected Area (draft Northern Adelaide Coastal Wetlands
Background Paper).
Page 180
GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – YANKALILLA BIOUNIT
XXII
MARINE BIOGEOGRAPHY AND CONSERVATION VALUES OF THE
YANKALILLA BIOUNIT
This biounit extends from Marino Rocks (just north of Hallett Cove) to Rapid Head and covers an area of
51,561 ha. It faces west into Gulf St Vincent.
MARINE BIOGEOGRAPHY
1
−
OCEANOGRAPHY
Predominantly moderate wave energy environment
with moderate to high wave energies during winter.
Major Benthic Communities
•
2
GEOLOGY
AND
GEOMORPHOLOGY40
COASTAL
−
In the Hallett Cove region, pre-Cambrian aged
rocks form spectacular cliffs separating the
Adelaide Plain from the Willunga Basin. There are
several pocket beaches along the coast.
In the Willunga region, large exposures of Tertiary
marine sediments form low soft cliffs and
headlands with numerous pocket beaches. A
significant river outlet and estuary occurs at
Onkaparinga. The southern end of the basin is
bounded by further exposures of pre-Cambrian
aged rocks (D. Fotheringham, pers.comm.)
The long wide sandy beaches and high exposed
cliffs in the metropolitan region that characterise
the northern section of this biounit, give way to
alternations of lower headlands and smaller bays.
Small pocket beaches occur at intervals such as at
Myponga and Normanville.
•
−
3
BIOLOGY
Major Habitats
−
Major intertidal habitats in the region include
mostly bays, rocky cliffs and platforms, and
sandy beaches.
Of the total inshore subtidal habitats mapped
in the biounit (25,456 ha), sandy bottoms
comprise 15,845 ha (62.2%), seagrass
meadows comprise 7,646 ha (30.0%), and
reefs comprise 1,966 ha (7.7%).
Macroalgal
Wave exposure increases from Aldinga Bay to
Cape Jervis. On moderately exposed rocky
shores and reefs in this region (eg. Port
Noarlunga Reef, Aldinga Reef, Carrickalinga
Head), shallow reef areas are dominated by
Ecklonia radiata and species of Cystophora
(C.siliquosa, C.subfarcinata, C.monilifera,
C.moniliformis, C.expansa, C.brownii), and
Sargassum (S.decipiens, S.fallax), with an
understorey
of
Lobophora
variegata,
Caulerpa (C.racemosa and red algae. In more
sheltered areas (eg. Rapid Bay), species such
as Scaberia agardhii and Caulocystis ulvifera
occur as sub-dominants with species of
Sargassum (S.decipiens) and Cystophora
(C.expansa, C.monilifera) and with an
understorey of the prostrate brown algae,
Lobophora variegata.
Seagrasses
Extensive seagrass meadows occur in this
region, in Aldinga Bay and Yankalilla Bay,
and also in shallow, sandy, offshore areas
adjacent to reefs and boulder fields. Sandy
sediments are commonly colonised by species
of Posidonia (P.sinuosa, P.angustifolia),
Amphibolis
antarctica
and
Halophila
australis, which often occurs adjacent to reef
communities and in deep water (ie. 20m).
Patches of Posidonia coricea also occur in the
shallow waters of Aldinga Bay.
40
From Fleurieu Coast Protection District Study Report
(Llewellyn-Davies et al. 1977).
Page 181
GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – YANKALILLA BIOUNIT
Coastal and Offshore Islands (or Reefs)
−
Marino Rocks is a wide intertidal platform
with large boulders that is exposed to
moderately high wave energy. Barnacles,
mussels, various gastropods and sea anemones
are found here.
−
Port Noarlunga Reef.
−
Aldinga Reef.
−
`Five mile reef' (offshore from Wirinna).
−
The estuary itself extends 16 km inland from
the mouth, and is protected as the
Onkaparinga Conservation Park (1 587 ha)
and the Onkaparinga Estuary Aquatic Reserve.
It is comprised of three major habitat types: (i)
the upper tidal reaches of the river, (ii) the
lagoon/floodplain habitat in the lower reaches
of the estuary, and (iii) the remnant sand
dunes near the river mouth. The floodplain of
the Onkaparinga Estuary is characterised by
salt-tolerant samphires and areas of sandy
marine and estuarine mudflats which are in
part colonised by Eelgrass, Zostera muelleri.
The seagrass habitat in turn provides food
and/or shelter for the fishes which frequent the
lower reaches of the river. The estuary is a
recognised spawning area for Black Bream,
Acanthopagrus butcheri, and a nursery area
for Yellow-Eye Mullet Aldrichetta fosteri. As
total of 23 species of fish have been recorded
in the estuary, including Yellow-Eye Mullet,
Jumping Mullet, Liza argentea, Black Bream,
and Congolli, Pseudaphritis urvilli, Australia
Salmon, Arripis truttacea, Southern Sea
Garfish, Hyporhampus melanochir, and
Bridled Goby, Gobius bifrenatus. Large birds
such as White-Faced Heron, Egretta
novaehollandiae, Great Egrets, Ardea alba,
and Royal Spoonbills, Platalea regia,
commonly feed in the shallows and swamp
areas on the diverse animal life consisting
mainly of polychaete worms and crustaceans
(small crabs etc.). Threatened species of
waterbirds recorded in the area include the
Musk Duck, Biziura lobata (Sv), Cape Barren
Goose, Cereops novaehollandiae (Sv),
Latham’s Snipe, Gallinago hardwickii (Sv)
and the Australasian Shoveler, Anas
rhynchotis (Sr). A total of 50 species of
waterbird have been recorded in the area: 7 are
listed under international treaties. Adjacent to
the estuary there is a recreation park, managed
by the South Australian National Parks and
Wildlife Service.
−
The Onkaparinga River is tidal as far as the
township of Old Noarlunga. During the
summer months the river receives minimal
freshwater flow and deposits of sand inshore
close the mouth of the river, creating a lagoon
in the lower portion of the estuary. Hundreds
of years ago the former mouth of the river was
further north and its exit was through "The
Gap" of Port Noarlunga Reef. The sand dunes
near the river mouth are sparsely vegetated
with introduced species, planted as part of a
dune stabilisation program, and provide
protection to the lagoon/floodplain to the east
of the dunes.
Rivers and Estuaries
−
Onkaparinga Estuary (which flows out to sea
at Port Noarlunga).
−
Pedler Creek (which flows out to sea at the
Moana Sands Conservation Park).
−
Myponga River.
−
Yankalilla River.
−
Bungala River.
−
Carrickalinga Creek.
MARINE CONSERVATION VALUES
1
1.1
SIGNIFICANT
BIOLOGICAL
PHYSICAL FEATURES
AND
Biological
Coastal and Marine Wetlands of National
Importance
−
The Onkaparinga Estuary (60 ha) comprises
an environment which is not common
elsewhere in Australia. It represents the
largest estuary between the Glenelg River in
south-western Victoria and Blackwood River
in south-western Western Australia, and the
third largest permanent river in South
Australia (after the Murray and Port Adelaide
River). The coastal samphire community
within the reserve is the only example of this
community type south of Adelaide along the
eastern shores of Gulf St.Vincent.
Page 182
GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – YANKALILLA BIOUNIT
Within the pools on the shoreward edge of the
reef, Ulva sp. (green Sea Lettuce), and patches
of seagrass occur, including Heterozostera
(Eelgrass) or Zostera muelleri (Garweed).
Small rock crabs and hermit crabs (Paguristes
frontalis) are also found.
On the outer
intertidal edge of the reef is a band of red turf
algae, the most common species present is
Gelidium pusillum. Off the edge of the reef to
about 10 m deep, kelp plants (Ecklonia
radiata), about one metre high, are most
common. In rocky areas Cystophora spp. and
Sargassum spp. occur. Some of the sandy
areas between the rocks and to the north and
west of the reef support the seagrasses, Zostera
muelleri (Garweed), Amphibolis antarctica
(Wireweed)
and
Posidonia
sinuosa
(Tapeweed). There are numerous reef fish,
shells, sponges, hydroids and sea squirts.
Some 1200 m offshore, north-west from
Snapper Point, there is a spectacular under
water cliff (the "drop-off") of about 10 m
down to 21m.
Here gorgonian corals,
numerous sponges and many reef fish may be
observed. Further away from the reef, where
the seafloor is sandy, the occasional scallop
and clump of stalked orange red ascidian
(Pyura spinifera) are found.
Other Areas of Recognised Conservation
Significance
−
−
Port Noarlunga Reef (240 ha) which is part of
the Onkaparinga Estuary Aquatic Reserve.
The reef is formed from a consolidated
Pleistocene sand dune, is 1.6 km long and lies
some 400m offshore. It is separated into two
reefs by a channel called "The Gap". A jetty
runs out from the shore almost to the reef, so
swimming is the only access to the reeftop,
which may be explored at low tide. On the
flat reeftop is an algal-mussel community
dominated by the small black mussel,
Modiolus pulex, and an assemblage of turf
algae including species of Corallina, Gelidium
and Codium capitulatum. Below the low
water mark, kelp plants (Ecklonia radiata)
about one metre high, dominate the outer reef
slope. Other large brown algae, such as
Cystophora moniliformis, C.subfarcinata and
C.monilifera, and Sargassum species are
common on the calmer, inside edge of the
reef. Beneath the canopy of these large brown
algae, smaller green, brown and red seaweeds
form an understorey. In addition to the
abundant plant life, numerous sedentary
organisms such as bryozoans, sponges,
hydroids,
ascidians
(Sea-Squirts)
and
molluscs, including the Blacklip Abalone,
(Haliotis rubra) and Pheasant shells
(Phasianella spp.), also form part of the reef
marine community. A rich sponge-hydroid
community may be seen at the southern end of
the northern reef. Many species of reef fish
including
Magpie
Perch,
Scalyfin,
Leatherjackets, Wrasses, Herring Cale, Coral
Fish, Tommy Ruff, and Salmon Trout may
also be seen near the reef.
Aldinga Reef Aquatic Reserve (505 ha) is a
large intertidal platform and reef complex.
The intertidal platform consists of tertiary
limestone that extends approximately 500 m
offshore. The reef complex extends some
1,200 m offshore from Snapper Point where,
at the seaward edge of the reef, there is a
spectacular 'drop-off' with a precipitous
underwater cliff of about 10 m. The cliff and
overhangs are extremely rich in marine life,
particularly sponges.
Locally endangered
species include: Gorgonia (Melithaea species)
and Blue Groper (Achoerodus gouldii). The
most common organism of the northern reef
flat is the brown alga, Hormosira banksii (or
Sea Grape). The southern section of the
intertidal reef provides more sandy and rock
pool areas and is colonised by a larger variety
of marine plants including H. banksii, and the
brown alga, Caulocystis uvifera.
−
Yankalilla Bay, is a large shallow, seagrassdominated embayment, which extends from
Carrackalinga Head to Rapid Head. The bay
contains the most extensive meadows of
seagrass of any area south of metropolitan
Adelaide, along the eastern shores of Gulf St
Vincent.
Within the bay, the relatively
unspoilt isolated shallow, reef areas and
seagrass meadows are also home to a wide
range of fauna and flora, including rare fish
species, such as the Leafy Sea Dragon,
Phycodurus eques and species such as Blue
Groper, which have been heavily reduced in
many parts of the gulf. In particular, reef
areas with subtidal boulders and rocks around
Second Valley (eg. `Lasseter’s reef’), Rapid
Head, Carrickalinga and Normanville,
although not formally documented, are known
to be rich in marine flora and fauna, and rare
or uncommon fish species. Lasseter’s reef, in
Second Valley, and Rapid Head are popular
dive spots and are listed in `Dive South
Australia: The Best Dive Sites in South
Australia’ (Diving Industry Association of
South Australia). The 50m dome-shaped reef
is home to a wide range of marine life,
including Leafy Sea Dragons, and is very
exposed.
Page 183
GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – YANKALILLA BIOUNIT
−
1.2
Further offshore, `Five mile reef' is a popular
place for fishers and divers. Fish observed
here include reef fish such Harlequin,
Boarfish, Blue Groper and the Blue Devil,
species which have generally disappeared
from shallow offshore reef areas closer to
metropolitan Adelaide
Physical
−
2
2.1
Geological Monuments
−
Hallett Cove: Palaeozoic glaciation and type
section in Waterfall Creek. The adjacent
Hallett Cove Conservation Park is on the
Register of the National Estate.
−
O'Sullivan Beach: glacial dropstone
Precambrian Reynella Siltstone.
in
−
Witton Bluff, South Bank: Tertiary beds.
−
Onkaparinga Mouth-Seaford: Tertiary beds
(reference sections).
−
Maslin Bay-Aldinga Bay: Tertiary Type
sections in the coastal cliffs. The area is also
on the Register of the National Estate.
−
Sellicks Beach: Willunga Fault.
−
Myponga Beach: Sellick Hill Limestone and
Fork Tree Limestone. Part of the area is also
on the Register of National Estate, while the
whole area is on the State List.
−
Carrickalinga Head: Heatherdale Shale and
Type Locality for Carrickalinga Head
Formation. This area is also on the Register of
the National Estate.
−
Normanville Sand Dunes: recent dunes along
coast. This area is also on the Register of the
National Estate.
−
South Yankalilla Beach, Little Gorge Area:
Unconformity Precambrian Inlier with
Adelaidean.
−
Second Valley Harbour: coastal cliffs
containing structures in Precambrian marbles
and slates. This area is also on the State
Heritage List.
Cape Jervis: type section for Cape Jervis Beds,
and Permian Glaciation. This area is also on
the State Heritage List and the Register of the
National Estate.
OTHER VALUES
Commercial Fisheries
The major single species fishery that operates in
this northern area is the Western King Prawn.
Boats trawl in the gulf sometimes within a few
kilometres of the shore. There is also a marine
scalefish fishery, especially netting. Commercial
harvesting of abalone in this region is negligible.
Western King Prawn
This biounit is located within the waters of the Gulf
St Vincent prawn fishery, which comprises 10
license holders (ie. boats). All vessels fish within
the waters of the Gulf St Vincent and Investigator
Strait biounits (ie. Sturt, Investigator, Orontes,
Clinton, Yankalilla, Nepean, Encounter, St
Vincent). In 1995/96 and 1996/97 a total of
258,459 and 210,581 kg was caught for this
fishery, with a total effort of 2,996 and 3,235 hours,
respectively (or 11.38% and 10.41% of the total
catch for Western King Prawn in South Australian
waters).
Southern Rock Lobster
This biounit encompasses 2 fishing zones: Fishing
Zone 43 and 44. No lobsters were recorded in
1995/96 and 1996/97 off the southern metropolitan
coast, in the northern section of this biounit (ie.
Fishing Zone 43). However, lobster fishing is
present in the southern section of this biounit which
encompass the waters of the southern Fleurieu
Peninsula and Backstairs Passage (and also, north
western Kangaroo Island) (ie. Fishing Zone 44).
In 1995/96 and 1996/97 a total of 8 and 6 licensed
operators fished in this region (ie. Fishing Zone
44), catching approximately 7,036 and 5,390 kg of
lobsters, respectively (or 0.14% and 0.11% of the
total catch for Southern Rock Lobster in South
Australian waters).
Page 184
GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – YANKALILLA BIOUNIT
The major single species fisheries that operates in
this southern area is Western King Prawn.
Abalone
There is negligible commercial harvesting of
Greenlip Abalone in this biounit, (ie. MapCode
25A-D, Yankalilla Bay to Port Elliot, including
Backstairs Passage and the Pages). In 1995/96 a
total of 3498 kg of Blacklip was harvested within
this region, which represented 8.3% of the total
Blacklip Central Zone catch (or 0.76% of the total
catch for Blacklip in South Australian waters). No
Blacklip were harvested in this region in 1994/95.
Marine Scalefish Fisheries
The Yankalilla Biounit encompasses 2 fishing
zones: Fishing Zone 43 and 44. During 1995/96
and 1996/97, 26 and 17 commercial licence holders
(made up of Marine Scalefish and Restricted
Marine Scalefish licence categories) caught
commercial marine scalefish species from the
northern section of this biounit (ie. Fishing Zone
43), respectively.
License holders expended
approximately 733 and 720 boat days effort fishing
these waters during 1995/96 and 1996/97,
respectively. The marine scalefish catch for this
region (ie. Fishing Zone 43) represented 29,984 kg
in 1995/96 and 40372 kg in 1996/97(or 0.29% and
0.39% of the total catch for the marine scalefish
fishery in South Australian waters). In the southern
Fleurieu and Backstairs Passage region, (ie. Fishing
Zone 44), a total of 47 and 37 licensed operators
fished 2,496 and 2,126 days in this region in
1995/96 and 1996/97, catching approximately
171,288 and 129,167 kg of lobsters, respectively
(or 1.65% and 1.27% of the total catch for the
marine scalefish fishery in South Australian
waters).
At Cape Jervis there are 10-15 full time line fishers
(hand and long line). Main species caught are
Southern Calamari (Sepioteuthis australis) over
seagrass beds, and Snapper (Pagrus auratus)
between 50m and 10m. Beach seining occurs on
sandy beaches adjacent Cape Jervis for Salmon and
Mullet.
Backstairs Passage has an active hand/long line
snapper industry. Southern Calamari is taken by
jig nearer to Cape Jervis. Some Garfish is also
taken here.
Although license holders are not restricted to
fishing in this biounit, the following licenses are
registered in this area:
−
2.2
Port Willunga: 1 unrestricted marine scalefish
−
Glenelg: 1 unrestricted marine scalefish
−
Port Noarlunga:
scalefish
1
unrestricted
Aquaculture
There is currently no aquaculture development in
this region.
The Gulf St Vincent/Fleurieu
Aquaculture Management Plan (Berggy 1996)
proposes limited aquaculture development in this
region:
Fleurieu Policy Area
−
West Fleurieu Management Zone (coastal
waters, within 3nm of the coast, from Sellicks
Beach, south to Cape Jervis, excluding Rapid
Bay) – zoned for limited aquaculture
development. Licenses will be considered for
a total of 30ha of aquaculture development in
this zone, excluding the culture of Pacific
Oysters.
−
Rapid Bay Aquaculture Zone (coastal waters
of Rapid Bay) – zoned for aquaculture
development. Licenses will be considered for
a total of 60ha of aquaculture development in
this zone.
−
East Fleurieu Zone (coastal waters, within
3nm of the coast, from Cape Jervis to the
Murray Mouth) – zoned to protect tourism,
recreation and conservation values. Licenses
will not be considered for aquaculture
development in this zone.
Although license holders are not restricted to fishing
in this biounit, the following licenses are registered in
this area:
−
Cape Jervis: 5 restricted marine scalefish.
marine
−
Normanville: 2 unrestricted marine scalefish
−
O'Sullivan's Beach: 2 unrestricted marine
scalefish
Page 185
GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – YANKALILLA BIOUNIT
2.3
Recreation and Tourism
−
Myponga: boat, rock and river fishing. Major
species: King George Whiting, Black Bream,
Yelloweye Mullet, Australian Salmon,
Snapper, Snook, Garfish, Tommy Rough,
Toothbrush Leatherjacket, Silver Drummer
and Southern Calamari.
−
There are three artificial reefs located at
Glenelg (dredge, suction barge and tyre
modules), one at Grange (tyre modules), and
one at Port Noarlunga (tyre modules).
−
Normanville, Carrickalinga: boat, beach and
rock fishing. Major species: King George
Whiting, Sand Flathead, Yelloweye Mullet,
Australian Salmon, Snapper, Snook, Garfish,
Tommy Rough, Toothbrush Leatherjacket,
Silver Drummer and Southern Calamari.
−
Second Valley: boat, jetty and rock fishing.
Major species: King George Whiting, Sand
Flathead, Yelloweye Mullet, Australian
Salmon, Snapper, Snook, Garfish, Tommy
Rough, Toothbrush Leatherjacket, Silver
Drummer and Southern Calamari.
−
Rapid Bay: jetty and boat fishing. Major
species: King George Whiting, Sand Flathead,
Yelloweye Mullet, Australian Salmon, Snook,
Garfish, Yellowtail Kingfish, Tommy Rough,
Trevally, Toothbrush Leatherjacket, Silver
Drummer and Southern Calamari.
−
Cape Jervis: jetty, boat and rock fishing.
Major species: King George Whiting,
Australian Salmon, Snapper, Snook, Garfish,
Bluefin Tuna, Tommy Rough, Toothbrush
Leatherjacket, Silver Drummer and Southern
Calamari.
Fishing
−
−
Because of its proximity to Adelaide and the
coastal suburbs, this entire biounit is very
popular for recreational fishing and is subject
to intense use.
Metropolitan coastline: boat, shore and jetty
fishing (Largs Bay, Semaphore, Grange,
Henley Beach, Glenelg, Brighton, Port
Noarlunga). Major species: King George
Whiting, Yellowfin whiting, Black Bream,
Sand Flathead, Yelloweye Mullet, Australian
Salmon, Snapper, Mulloway, Garfish, Blue
Swimming Crab and Tommy Rough.
−
O'Sullivan Beach ramp: boat, beach and rock
(breakwater) fishing. Major species: King
George Whiting, Yellowfin Whiting, Black
Bream, Sand Flathead, Yelloweye Mullet,
Australian Salmon, Snapper, Snook, Garfish,
Tommy Rough, Silver Drummer and Southern
Calamari.
−
Onkaparinga River: river and shore fishing.
Major species: Yellowfin whiting, Black
Bream, Yelloweye Mullet, Mulloway and
Garfish.
−
Moana: boat and beach fishing.
Major
species: King George Whiting, Sand Flathead,
Yelloweye Mullet, Australian Salmon,
Snapper, Snook, Garfish, Tommy Rough,
Toothbrush Leatherjacket, Silver Drummer
and Southern Calamari.
−
−
Aldinga Beach: boat and beach fishing. Major
species: King George Whiting, Sand Flathead,
Australian Salmon, Snapper, Snook, Garfish,
Tommy Rough, Toothbrush Leatherjacket,
Silver Drummer and Southern Calamari.
Sellicks Beach: boat, shore and wharf fishing.
Major species: King George Whiting,
Yellowfin Whiting, Black Bream, Sand
Flathead, Yelloweye Mullet, Australian
Salmon, Snapper, Mulloway, Garfish, Blue
Swimming Crab and Tommy Rough.
Tourism
−
The metropolitan coast is the main swimming
and boating area for Adelaide residents.
Maslins Beach, south of Adelaide, has a
section for nudist bathing which has proven to
be very popular.
Page 186
GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – YANKALILLA BIOUNIT
−
SCUBA diving: there are several popular dive
spots in the southern metropolitan Adelaide
region and Fleurieu Peninsula.
Port
Noarlunga reef, Noarlunga tyre reef, the
`Lumb’, the Stanvac barges, the Aldinga dropoff, Aldinga Pinnacles, Lasseters reef (Second
Valley), Rapid Bay jetty, Rapid Head, the
Bluff (Victor Harbour), West Island, and
Blowhole Creek, are all recognised dive spots
and are listed in `Dive South Australia: The
Best Dive Sites in South Australia’ (Diving
Industry Association of South Australia). The
dive at Rapid Bay jetty has been described by
Reg Lipson as one the best jetty dives in
Australia. Both Rapid Bay and Second Valley
jetties are used an open water dive training
sites.
−
Port Noarlunga Reef and the Onkaparinga
estuary Aquatic Reserve is one of South
Australia’s most intensively used and best
known Aquatic Reserves, with over 170 000
visitors each year (Sutherland 1987) and an
estimated 6000 SCUBA divers over summer
(Papple 1990).
−
Onkaparinga estuary: fishing, canoeing,
picnicking, bushwalking, bird watching and
swimming.
−
Myponga: boating, fishing, holiday shacks,
boat ramp, hang-gliding.
−
Normanville/Carrickalinga: jetty
boating, swimming, SCUBA diving,
2.4
Scientific Research and Education
−
Port Noarlunga reef is used by schools,
tertiary institutions and SCUBA diving clubs
for education in the marine environment. It is
a popular training place for new divers and
snorkellers, with an estimated 6000 SCUBA
divers annually over the summer period
(Papple 1990). In 1994, the Port Noarlunga
reef underwater interpretation trail was
established on the north reef of Port
Noarlunga, to raise community awareness of
temperate reef environments and marine life
(see Andrews & Edyvane 1996). The trail, the
first of it’s kind in South Australia, was
established by the SA Research and
Development Institute, in consultation with
the local community. The 800m trail consists
of 12 underwater concrete trail markers (with
educational plaques) and runs south from the
Noarlunga jetty, along the shoreward edge of
North reef, through the Gap, and then north
along the outside of the reef. Each plaque
provides information on the reef ecosystem
and also, the reef inhabitants.
−
Port Noarlunga Primary School and Aquatic
Centre plays a major role in school-based
marine and coastal educational activities
within the Port Noarlunga Reef and
Onkaparinga Estuary Aquatic Reserve. The
centre offers a wide range of outdoor
activities, including snorkelling, sailing and
kayaking.
−
Aldinga Reef is also used by many
metropolitan schools and institutions for
marine education activities.
fishing,
−
Wirrina tourist resort, camping.
−
Lady Bay: scenic point, diving offshore at `5
mile reef'.
−
Second Valley: jetty fishing, boating,
camping, diving, hang-gliding.
This is
considered a particularly spectacular scenic
area.
−
Hallett Cove Conservation Park (51 ha).
−
Onkaparinga River Recreation Park (285ha)
−
Rapid Bay: jetty fishing, diving, camping,
boating.
−
Onkaparinga River National Park (1,332 ha).
−
Cape Jervis: fishing, boating, hang gliding,
ferry departures for Kangaroo Island, SCUBA
diving.
−
Moana Sands Conservation Park (21 ha).
−
Aldinga Scrub Conservation Park (239 ha):
preserves a significant remnant of the natural
habitat that once occurred all along the
southern Adelaide coastline.
2.5
Adjacent Land Use
National and Conservation Parks
Page 187
GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – YANKALILLA BIOUNIT
European
Agriculture/Industry
−
−
Most coastal land in this biounit is used for
housing or holiday shacks. Some agricultural
land occurs further south past Port Noarlunga.
Very little uncleared or undeveloped land
remains in this biounit.
There is an oil refinery at Port Stanvac with
deep port facilities.
•
Pollution sources:
−
Port Stanvac Refinery ballast water discharge
−
O'Sullivan Beach sewage effluent outfall
−
Mixed farming along the coast.
−
At Rapid Bay limestone mining occurs.
•
Pollution sources:
−
Rapid bay jetty/quarry
−
River Bungala outlet
−
Myponga river outlet
Urban Centres
−
No major urban centres occur along this
biounit. However, there are several small
coastal centres with populations of less than
200 persons.
These include, Myponga,
Carrickalinga, Lady Bay, Second Valley,
Rapid Bay and Normanville. These areas are
predominantly used as holiday areas and
consist primarily of beach houses and shacks.
2.6
Features
Significant Cultural and Historical
Shipwrecks
−
`Tigress’ (1840-1848): a two-masted wooden
snow which was swept onto a reef during a
storm, 2 kilometres south of the Onkaparinga
River with 2 lives lost.
−
`Star of Greece’ (1868-1888): a three-masted
iron ship that was blown ashore near Port
Willunga during a storm, with 18 crew
members killed.
−
There are also several artificial reefs in the
area, including: the Noarlunga tyre reef
(located 2.5kms west of the Noarlunga jetty in
20m of water); the `Lumb’ (a tug sunk in 1994
as a dive site, 20m west of the Noarlunga tyre
reef); and the Stanvac barges (3 barges sunk
approximately 5kms west of the Port Stanvac
oil refinery). All are recognised dive spots
and are listed in `Dive South Australia: The
Best Dive Sites in South Australia’ (Diving
Industry Association of South Australia).
3
CURRENT CONSERVATION STATUS
OF THE YANKALILLA BIOUNIT
−
Marine Reserves
Port Noarlunga Reef & Onkaparinga Estuary
(300 ha)
−
Aldinga Reef (505 ha)
−
Marine Parks
None
−
Aboriginal
The Kaurna people lived in this region and
regularly migrated to the coast to fish and collect.
Artefacts and in some instances, human remains,
have been found at various locations along the
coast, especially Sellicks Beach, Aldinga,
Onkaparinga and Hallett Cove. A register of
important sites is kept by the Aboriginal Heritage
Branch of the Department of Environment and
Planning. For confidentiality, these sites are not
available for publication.
−
Netting Closures
Metropolitan beaches (all waters of Gulf Saint
Vincent within 600 metres of high water mark
between the seaward end of the southernmost
Outer Harbor breakwater and the southern
boundary of the Aldinga Aquatic Reserve).
Onkaparinga River (all waters of the River).
Page 188
GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – YANKALILLA BIOUNIT
marine wetlands and habitats, seagrass
meadows, reefs, estuaries-Myponga River,
major fisheries-King George Whiting, Garfish,
Calamari), economic (marine scalefish
fisheries,
tourism),
social
(recreation,
shipwrecks-`Star of Greece), national (potential
for listing on Register of National Estate),
practicality
(insulation,
accessibility,
compatibility-adjacent to Aldinga Scrub
Conservation Park, Aldinga Aquatic Reserve ).
4 AREAS OF HIGH CONSERVATION
VALUE IN THE YANKALILLA BIOUNIT
Onkaparinga Estuary-Moana
−
Prime IUCN Conservation Values: education,
biodiversity, social values (IUCN Category II).
IUCN Identification Criteria: biogeographic
(`geological
monuments'-Witton
Bluff,
Onkaparinga
Mouth-Seaford),
ecological
(range of coastal marine habitats, estuariesOnkaparinga River, Pedler Creek, reefs,
seagrass meadows, major fisheries-King
George Whiting, Garfish, Western King Prawn,
breeding colonies of White-faced Herons,
Egrets, Spoonbills), economic (marine scalefish
fisheries,
tourism),
social
(recreation,
education-Port Noarlunga Primary School and
Aquatic
Centre,
shipwrecks-`Tigress',
aboriginal heritage area-Moana Sands),
national (Wetland of National ImportanceOnkaparinga Estuary, nominated for listing on
Register of National Estate), practicality
(insulation, accessibility, compatibility-adjacent
to Port Noarlunga and Onkaparinga Aquatic
Reserve, Moana Sands Conservation Park).
Aldinga Bay-Myoponga Estuary
−
Prime
IUCN
Conservation
Values:
biodiversity, education, social values (IUCN
Category II). IUCN Identification Criteria:
biogeographic (rare remnant of coastal
vegetation along southern metropolitan
Adelaide coastline, `geological monuments'Maslin Bay-Aldinga Bay, Sellicks Beach,
Myponga Beach), ecological, (range of coastal
Yankalilla Bay
−
Prime
IUCN
Conservation
Values:
biodiversity,
rare
and
endangered
species/habitats, social values (IUCN Category
II).
IUCN
Identification
Criteria:
biogeographic (largest intact seagrass meadows
along the metropolitan and Fleurieu Peninsula
coastline,
`geological
monuments'Carrickalinga Head, Normanville Sand Dunes,
South Yankalilla Beach, Second Valley
Harbour), ecological, (wide range of coastal
marine wetlands and habitats, extensive
seagrass meadows, reefs-5-mile reef, Lasseter’s
reef, estuaries-Bungala River, Yankalilla River,
Carrickalinga Creek, reef fish populations,
`endangered' Leafy Sea Dragon), economic
(marine scalefish fisheries-King George
Whiting, Calamari, Snapper, tourism), social
(recreation, SCUBA diving), national (potential
for listing on Register of National Estate),
practicality (accessibility).
Page 189
GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – ENCOUNTER BIOUNIT
XXIII MARINE BIOGEOGRAPHY AND CONSERVATION VALUES OF THE ENCOUNTER
BIOUNIT
This biounit extends from Rapid Head on the southwest Fleurieu Peninsula, to the Murray Mouth, and covers an
area of 39,389 ha and a coastal distance of approximately 100 km. The waters of Backstairs Passage and the Pages
offshore islands are classified within the Backstairs Biounit (see Kangaroo Island Coast).
MARINE BIOGEOGRAPHY
1
3
Major Inshore Habitats
OCEANOGRAPHY
The coast from the Murray Mouth westward to Cape
Jervis, increases from low wave energy to high
energy.
2
GEOLOGY
AND
GEOMORPHOLOGY 41
BIOLOGY
−
Major intertidal habitats in the region include
mostly rocky shores, sandy beaches and bays
(Encounter Bay).
−
Of the total inshore subtidal habitats mapped
in the biounit (9,439 ha), reefs comprise 5 452
ha (57.8%), sandy bottoms comprise 3 482 ha
(36.9%), and seagrass meadows comprise 505
ha (5.4%).
COASTAL
From Cape Jervis to Rosetta Head there are
spectacular steep cliffs, with direct exposure to the
open waters of the Southern Ocean. At Rosetta
Head the coastal morphology changes from cliffs to
long sweeping beaches backed by dunes and
interspersed at the western end by the granite
outcrops of Rosetta Head itself, Granite Island and
Freeman Nob. Granitic rocks also form rounded
hills on promontories and offshore islands such as
Wright Island, West Island and Seal Island. At
Tunkalilla Beach, Waitpinga Beach, Victor
Harbour and near Middleton, older Quaternary
deposits of high level alluvium, outwash gravels,
and laterised and kunkarised surface deposits form
eroding cliffs three metres high exposed beneath
recent sands.
Tunkalilla, Parsons and Waitpinga Beaches are all
high energy beaches backed by steep hills. The
Inman and the Hindmarsh Rivers open to the sea only
by flood waters and high tides, creating lagoons
behind the beaches otherwise.
The type section of the Kanmantoo Group of rocks
is recorded along this stretch of coast.
Major Benthic Communities
•
−
Macroalgal
The rocky shores and reefs of the south coast
of Fleurieu Peninsula, east of Cape Jervis,
generally experience greater wave exposure
and strong tidal currents (through Backstairs
Passage). On these exposed shore and reefs
(eg. Porpoise Head, Tunkalilla, Newland
Head, The Pages), reef areas are dominated by
mixed sponges, hydroids, ascidians and
bryozoans and large brown algae (ie.
Scytothalia
dorycarpa,
Carpoglossum
confluens, Ecklonia radiata, Seirococcus
axillaris, Acrocarpia paniculata, Carpopeltis)
with species of Cystophora (C.moniliformis,
C.retorta) and species of Sargassum
(S.sonderi, S.paradoxum) as sub-dominants,
with an understorey of red algae (ie.
Phacelocarpus, Plocamium, Rhodophyllis)
and coralline algae (eg. Haliptilon,
Metagoniolithon).
41
From Fleurieu Coast Protection District Study Report
(Llewellyn-Davies et al. 1977).
Page 190
GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – ENCOUNTER BIOUNIT
•
Seagrasses
−
Seagrass meadows are sparse in this region
and are restricted to the sheltered embayments
of Encounter Bay. Sandy sediments are
commonly colonised by species of Posidonia
(P.sinuosa,
P.angustifolia),
Amphibolis
antarctica and Halophila australis, which
often occurs adjacent to reef communities and
in deep water (ie. 20m).
invertebrates, a rich diversity of invertebrate
species such as hydroids, bryozoans,
ascidians, seastars and brittlestars, chitons,
anenomes, gastropods and other molluscs, and
crustaceans. (Shepherd & Watson 1970,
Kangas & Shepherd 1984). The Encounter
Bay region also contains highly abundant and
diverse assemblages of high marine animals,
such as ray and skate species, a variety of
shark species (gummy, school, whiskery,
bronze whalers), economically important
molluscs such as Greenlip and Blacklip
Abalone and the Goolwa Cockle (Baker &
Edyvane 1996). Importantly, Encounter Bay
also provides refuge for several rare,
uncommon, and.or endangered species, such
as the Southern Right Whale; the Australian
Sea Lion; species of Sygnathids (ie Leafy and
Weedy
Seadragons,
Pipefishes
and
Seahorses); the unusual octopus Argonauta
nodosa, which creates the "paper nautilus" egg
cases; a diversity of pycnogonid (sea spider)
species, and has very diverse and dense
articulated bryozoan communities (Baker &
Edyvan
1996,
S
Shepherd
SARDI
pers.comm.). The Zostera beds in the region,
particularly around Granite and West Islands,
are also the only known location for a number
of rare species of hemichordates (S Shepherd,
SARDI pers.comm.). A rare phototrophic
sponge species, Cymbastela sp., has been
found in the sheltered subtidal habitats off
West, Wright and Seal Islands and along the
oceanic coast of Victor Harbor (Cheshire et al
1995).
Rivers and Estuaries
−
Tent Rock Creek (Deep Creek Conservation
Park).
−
Inman River (Victor Harbour).
−
Hindmarsh
Harbour).
River
(north-east
of
Victor
Coastal and Offshore Islands (or Reefs)
−
Granite Island, Wright Island, West Island,
Seal Island and Pullen Island (Encounter Bay).
MARINE CONSERVATION VALUES
1
1.1
SIGNIFICANT
BIOLOGICAL
PHYSICAL FEATURES
AND
Biological
−
The globally protected endangered Southern
Right Whale (Eubalaena australis) annually
visits the Encounter Bay region during the
autumn to mid spring months for mating,
calving and rearing young, and can easily be
seen close to shore. During the 1980s and
1990s there has been an increase in the
number of whale sightings around Middleton,
Victor Harbour and the coastline to the west of
Encounter Bay.
Apart from the Great
Australian Bight, the Encounter Bay region is
the most significant area in South Australia for
migrant whales (Baker & Edyvane 1996).
−
Although the coastal sites along southern
Fleurieu Peninsula are generally areas of low
benthic floral diversity, the outer islands of
Encounter Bay (ie Grantie, Wright, West, Seal
and Pullen Islands) and Rosetta Head, display
high algal diversity, with over 200 species
recorded, including diverse red algal
assemblages (Shepherd & Womersley 1970).
Associated
with
these
macroalgal
communities are a diverse rang eof fish and
−
Marine life surrounding West Island is
presently protected within the West Island
Aquatic
Reserve,
which
comprises
approximately 84 ha.
The reserve was
established primarily for the protection of the
marine benthic organisms around the island
for long term ecological studies. The island
itself is located 800 metres offshore at the
north western end of Encounter Bay. As such,
it’s accessibility has made it a popular
research site for many marine biological
studies.
Major habitat types include,
submarine cliffs, crevices and caverns, sandy
and rocky seabed areas. The general features
of the algal vegetation change markedly
around the island passing from rough to more
sheltered coasts. Three habitat types have
been recognised: the rough water southern and
western coasts; the moderately rough water
sections on the eastern and northern shores;
and the semi-sheltered section of Abalone
Cove. To the lee of the island, extensive beds
of seagrasses are present.
Page 191
GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – ENCOUNTER BIOUNIT
−
−
A number of bird species that have been
recorded from the Encounter Bay region are
listed as vulnerable or rare for the State, but
only two of these are regularly seen – the
Hooded Plover (Thinornis rubricollis) and the
Fairy Tern (Sterna nereis). Hooded Plovers
are regarded as nationally rare and vulnerable
in South Australia, while Fairy Terns are
regarded as rare at both levels (Garnett 1992).
West Island and Granite Island support rich
birdlife including large and important sites for
breeding colonies of sea birds including, Little
Penguins (Eudyptula minor), Silver Gulls,
Crested Terns, Caspian Terns and Fairy Terns.
Up to 50 pairs of Fairy Terns nested
irregularly on Wright Island and West Island
in the 1960s and in 1975-1976, but although
one or two birds are seen regularly in the bay,
there have been no further breeding records in
the past 20 years. Hooded Plovers are seen in
small numbers on sandy beaches in the region
and breed nearby. Rosetta Head also has a
population of Little Penguins. Birdlife is
presently protected within the West Island
Conservation Park, which includes Seal
Island. The park is also on the Register of the
National Estate.
Granite Island has a
Recreation Park, and is, likewise, on the
Register of the National Estate.
Encounter Bay appears, on the limited data
available, to be one of the most signficant
locations in the State for both, the Leafy
Seadragon (Phycodurus eques) and the Weedy
Seadragon (Phyllopteryx taeniolatus), which
are listed on the IUCN Red List as data
deficient (Hudson & Mace 1996). Leafy and
Weedy Sea Dragons are highly ornate species
of sea horse which are camouflaged to
resemble the seaweeds and seagrasses in
which they hide. They are considered to be
highly unusual and beautiful creatures and are
currently fully protected. Sea dragons are
generally associated with
the algal
communities at West Island and Rosetta Head
(ie the Bluff) and also, around the rocky areas
of Encounter Bay.
Encounter Bay also
supports populations of other threatened
species of the Family Sygnathidae (ie
seahorse, pipehorse (Solegnathus robustus)
and the Short-headed Seahorse (Hippocampus
breviceps). The former two are rated as
vulnerable and the latter as data deficient on
the IUCN Red List (Hudson & Mace 1996).
−
Although there are no major colonies of seals
in this region, sightings are made of the
Australian Sea Lion (Neophoca cinerea) and
Australian Fur Seal (Arctocephallus pusillis),
and it is possible that they are returning to this
area. For instance, Australian Fur Seals appear
to be returning to Seal Rock.
Although the coastal sites along southern Fleurieu
Peninsula are generally areas of low benthic floral
diversity, the outer islands of Encounter Bay
display high algal diversity, with over 200 species
recorded, including diverse red algal assemblages
(Shepherd & Womersley 1970). These islands
(Granite, Wright, West, Seal and Pullen Islands)
also contain subtidal habitats which contain a rich
diversity of invertebrate species such as hydroids,
bryozoans, ascidians, seastars and brittlestars,
chitons, anenomes, gastropods and other molluscs,
and crustaceans. (Shepherd & Watson 1970,
Kangas & Shepherd 1984). The Encounter Bay
region also contains highly abundant and diverse
assemblages of higher marine animals, such as ray
and skate species, a variety of shark species
(Gummy, school, whiskery, bronze whalers),
economically important molluscs such as Greenlip
and Blacklip Abalone and the Goolwa Cockle
(Baker & Edyvane 1996). Importantly, Encounter
Bay also provides refuge for several rate,
uncommon, and/or endangered species, such as the
Souther Right Whale; the Australian Sea Lion;
species of Sygnathids (ie Leafy and Weedy
Seadragons, Pipefishes and Seahorses); rare species
of hemichordate; the unusual octopus Argonauta
nodosa, which creates the “paper nautilus” egg
cases; a diversity of pycnogonid (sea spider)
species; and has very diverse and dense bryocoan
communities (Baker & Edyvane 1996, S Shepherd
SARDI pers comm.
Within Encounter Bay, the almost continuous and
extensive dense seagrass areas are the only
signficant areas of dense seagrass on the southern
Fleurieu Peninsula coast. This may explain the
regional importance of this region for Sygnathids
(Edyvane 1998). Likewise the extensive granite
reef system, which is a feature of Encoutner Bay
between Rosetta Head and the mouth of the Inman
River, is the only significant reef system on the
southern Fleurieu Peninsula coast (Edyvane 1998).
For these and other (cultural, social, geological)
reasons, Encounter Bay has been nominated as a
potential Marine Protected Area several times
during the past two decades (Halstead 1987,
Edyvane 1998). A full list of marine conservation
attributes of the Encounter Bay region is detailed in
Baker & Edyvane (1996) and more recently, in
Edyvane (1998).
Page 192
GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – ENCOUNTER BIOUNIT
−
−
−
−
−
As
well
as
displaying
considerable
biodiversity, the Encounter Bay region also
exhibits a high level of geodiversity. This is
due to the presence of the Encounter Bay
Granite Province, the variation within the
granite itself, and the inclusions, and also, the
metamorphic
eureole
surrounding
the
bathloith. Many features are best exposed in
the intertidal zone, for eg around the flanks of
Rosetta Head.
The waters around Granite and West Islands
are also the only known location for a number
of species of hemichordates (S. Shepherd,
SARDI, pers. comm.).
Marine life surrounding West Island is
presently protected within the West Island
Aquatic
Reserve,
which
comprises
approximately 84 ha.
The reserve was
established primarily for the protection of the
marine benthic organisms around the island
for long term ecological studies. The island
itself is located 800 metres offshore at the
north western end of Encounter Bay. As such,
it's accessibility has made it a popular research
site for many marine biological studies. Major
habitat types include, submarine cliffs,
crevices and caverns, sandy and rocky seabed
areas. The general features of the algal
vegetation change markedly around the island
passing from rough to more sheltered coasts.
Three habitat types have been recognised: the
rough water southern and western coasts; the
moderately rough water sections on the
eastern and northern shores; and the semisheltered section of Abalone Cove. To the lee
of the island, extensive beds of seagrasses are
present.
West Island and Granite Island also support
rich birdlife including large and important
sites for breeding colonies of sea birds
including, Little Penguins (Eudyptula minor),
Silver Gulls, Crested Terns, Caspian Terns
and Fairy Terns. Rosetta Head also has a
population of Little Penguins. Birdlife is
presently protected within the West Island
Conservation Park, which includes Seal
Island. The park is also on the Register of the
National Estate.
Granite Island has a
Recreation Park, and is, likewise, on the
Register of the National Estate.
Leafy and Weedy Sea Dragons are highly
ornate species of sea horse which are
camouflaged to resemble the seaweeds and
seagrasses in which they hide. They are
considered to be highly unusual and beautiful
creatures and are currently fully protected. Sea
dragons are generally associated with the algal
communities at West Island and Rosetta Head
(ie. the Bluff) and also, around the rocky areas
of Encounter Bay.
−
The deep waters of Backstairs Passage contain
massive sponges of more than 1 metre high
and wide. Large erect bryozoans (e.g. Adeona
grisea) dominate the bottom, and epizoic
crinoids and ophiuroids are especially
abundant on them. In the sediment drifts the
brachiopod Magadena cuingi reaches densities
of up to 80/m2 (Richardson & Watson 1975, in
Shepherd & Sprigg 1976).
−
Although there are no major colonies of seals
in this region, sightings are made of the
Australian Sea Lion (Neophoca cinerea) and
Australian Fur Seal (Arctocephallus pusillis),
and it is possible that they are returning to this
area. For instance, Australian Fur Seals
appear to be returning to Seal Rock.
−
Deep Creek Conservation Park is on the
Register of the National Estate. Within the
park, Blowhole Creek is a popular diving
location and is listed in `Dive South Australia:
The Best Dive Sites in South Australia’
(Diving Industry Association of South
Australia).
−
Newland Head Conservation Park is on the
Register of the National Estate.
1.2
−
Physical
The high cliff coastline of this biounit is
generally considered to be quite spectacular
and has, therefore, aesthetic qualities.
Geological Monuments
−
Middleton Beach: part of the Kanmantoo
Group and type section of Middleton
Sandstone with sedimentary structures.
−
Encounter Bay region (Port Elliot including
Commodore Point, Pullen Island, The Sisters
Rocks and Freeman Knob): Encounter Bay
Granite outcrops. This area is on the Register
of the National Estate.
−
Victor Harbour, banks of the railway cutting:
Late Pleistocene Anadara shell beds.
−
Victor Harbour, Granite Island and Seal
Island: Encounter Bay Granite and
Kanmantoo Group. On the Register of the
National Estate.
Page 193
GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – ENCOUNTER BIOUNIT
−
Rosetta Head/The Bluff, Petrel Cove and
Wright Island: Encounter Bay Granite contact
with Kanmantoo Group rocks including Petrel
Cove Formation Type Section. Rosetta Head
and Wright Island are on the Register of the
National Estate.
−
West Island, King Beach and King Point:
Encounter Bay Granite and Kanmantoo Group
Rocks. The Balquihidder Formation extends
West to Newland Head, which is on the
Register of the National Estate.
−
Headland between Waitpinga Beach and
Parsons Beach: part of Kanmantoo Group
Type section and Balquhidder Formation.
This headland lies within an Aboriginal site on
the Register of the National Estate. The
Kanmantoo Group type section continues
West from the end of Parsons Beach to Tunk
Head and beyond.
−
Tunkalilla Beach including old cliff line: part
of Kanmantoo Group type section.
−
Deep Creek: part of Kanmantoo Group type
section.
−
Cape Jervis: type section for Cape Jervis Beds
and Permian Glaciation. This area is on both,
the State Heritage List and the Register of
National Estate.
2
2.1
OTHER VALUES
Commercial Fisheries
Western King Prawn
This biounit is located within the waters of the Gulf
St Vincent prawn fishery, which comprises 10
license holders (ie. boats). All vessels fish within the
waters of the Gulf St Vincent and Investigator Strait
biounits (ie. Sturt, Investigator, Orontes, Clinton,
Yankalilla, Nepean, Encounter, St Vincent). In
1995/96 and 1996/97 a total of 258,459 and 210,581
kg was caught for this fishery, with a total effort of
2,996 and 3,235 hours, respectively (or 11.38% and
10.41% of the total catch for Western King Prawn
in South Australian waters).
Southern Rock Lobster
Backstairs Passage (and also, north western
Kangaroo Island) (ie. Fishing Zone 44). In
1995/96 and 1996/97 a total of 8 and 6 licensed
operators fished in this region (ie. Fishing Zone
44), catching approximately 7,036 and 5,390 kg of
lobsters, respectively (or 0.14% and 0.11% of the
total catch for Southern Rock Lobster in South
Australian waters).
Abalone
There is negligible commercial harvesting of
Greenlip Abalone in this biounit, (ie. MapCode
25A-D, Yankalilla Bay to Port Elliot, including
Backstairs Passage and the Pages). In 1995/96 a
total of 3498 kg of Blacklip was harvested within
this region, which represented 8.3% of the total
Blacklip Central Zone catch (or 0.76% of the total
catch for Blacklip in South Australian waters). No
Blacklip were harvested in this region in 1994/95.
Marine Scalefish Fisheries
The Encounter Biounit encompasses 2 fishing
zones: Fishing Zone 44 and 45. During 1995/96
and 1996/97, 21 and 17 commercial licence holders
(made up of Marine Scalefish and Restricted
Marine Scalefish licence categories) caught
commercial marine scalefish species from the
Encounter Bay section of this biounit (ie. Fishing
Zone 45), respectively. License holders expended
approximately 651 and 437 boat days effort fishing
these waters during 1995/96 and 1996/97,
respectively. The marine scalefish catch for this
region (ie. Fishing Zone 45) represented 52,019 kg
in 1995/96 and 35,468 kg in 1996/97(or 0.50% and
0.35% of the total catch for the marine scalefish
fishery in South Australian waters).
In the southern Fleurieu and Backstairs Passage
region, west of Newland Head (ie. Fishing Zone
44), a total of 47 and 37 licensed operators fished
2496 and 2,126 days in this region in 1995/96 and
1996/97, catching approximately 171,288 and
129,167 kg, respectively (or 1.65% and 1.27% of
the total catch for the marine scalefish fishery in
South Australian waters).
At Cape Jervis there are 10-15 full-time line fishers
(hand and long line). Main species targetted are
Southern Calamari (Sepioteuthis australis) which are
caught over seagrass beds, and Snapper (Pagrus
auratus) which are caught between 50 m and 10 m.
Beach seining for Salmon and Mullet occurs on the
sandy beaches adjacent Cape Jervis.
This biounit encompasses 2 fishing zones: Fishing
Zone 44 and Fishing Zone 45. In 1995/96 and
1996/97 a total of 3 and 2 licensed operators fished
in the waters of Encounter Bay (ie. Fishing Zone
45). In addition, lobster fishing is also present in
the waters of the southern Fleurieu Peninsula and
Page 194
GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – ENCOUNTER BIOUNIT
Some line fishing occurs at Deep Creek for King
George Whiting (Sillaginodes punctata) and
Snapper. There is also a small amount of netting for
Australian Salmon (Arripis trutta esper) and mullet
(eg. Aldrichetta forsteri), particularly around
Encounter Bay and Victor Harbour.
−
Central Gulf Management Zone (waters
offshore from Port Gawler) – zoned to provide
for aquaculture development. Licenses will be
considered for a total of 100ha of aquaculture
development in this zone, excluding the
culture of Pacific Oysters.
Backstairs Passage has an active hand/long line
Snapper fishery, while Southern Calamari is taken by
jig nearer to Cape Jervis. Some Garfish is also
caught here.
−
Investigator Strait/Backstairs Passage Zone
(waters of Investigator Strait and Backstairs
Passage)
–
zoned
for
aquaculture
development. Licenses will be considered for
a total of 50ha of aquaculture development in
this zone. Licenses will not considered for
developments east of line between Cape Jervis
and Penneshaw.
Although license holders are not restricted to fishing
in this biounit, the following licenses are registered in
this area:
−
Victor Harbour: 5 northern zone Rock Lobster
licenses, 1 southern zone Rock Lobster, 1
restricted marine scalefish license, 7
unrestricted marine scalefish licenses.
−
Port Elliot: 1 restricted marine scalefish
licence.
−
Goolwa: 1 unrestricted marine scalefish
license.
2.2
Fleurieu Policy Area
−
West Fleurieu Management Zone (coastal
waters, within 3nm of the coast, from Sellicks
Beach to Cape Jervis, excluding Rapid Bay) –
zoned for limited aquaculture development.
Licenses will be considered for a total of 30ha
of aquaculture development in this zone,
excluding the culture of Pacific Oysters.
−
−
Cape Jervis: boat, jetty and rock fishing.
Major species: King George Whiting,
Australian Salmon, Snapper, Snook, Garfish,
Bluefin Tuna, Tommy Rough, Toothbrush
Leatherjacket and Southern Calamari. There
is one charter boat operator based at Cape
Jervis.
−
Waitpinga and Parsons Beach: beach and rock
fishing. Major species: Black Bream, Sand
Flathead, Yelloweye Mullet, Australian
Salmon and Mulloway.
−
Port Elliot and Middleton: beach, jetty and
rock fishing. Major species: Sand Flathead,
Yelloweye Mullet, Australian Salmon,
Mulloway, Garfish, Tommy Rough, Trevally,
Toothbrush Leatherjacket and Southern
Calamari.
−
Victor Harbour, The Bluff (Rosetta Head) and
Granite Island: beach, boat, jetty and rock
fishing. Major species: King George Whiting,
Sand Flathead, Yelloweye Mullet, Australian
Salmon, Snapper, Mulloway, Sweep, Garfish,
Tommy Rough, Toothbrush Leatherjacket and
Southern Calamari.
East Fleurieu Zone (coastal waters, within
3nm of the coast, from Cape Jervis to the
Murray Mouth) – zoned to protect tourism,
recreation and conservation values. Licenses
will not be considered for aquaculture
development in this zone.
Open Waters Policy Area
Central Gulf Zone (offshore waters of central
Gulf St Vincent) – zoned to maintain
commercial and recreational use. Licenses
will not be considered for aquaculture
development in this zone.
Recreation and Tourism
Fishing
Aquaculture
There is currently no aquaculture in this region. The
Gulf St Vincent/Fleurieu Aquaculture Management
Plan (Berggy 1996) proposes no aquaculture
development in this region:
−
2.3
Tourism
−
Deep Creek Conservation Park is a popular
place for bushwalking and fishing at the
mouth of Blowhole Creek.
Page 195
GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – ENCOUNTER BIOUNIT
−
The entire Encounter Bay area is a major
tourist destination in South Australia. Victor
Harbour, Port Elliot and Goolwa are all
popular tourist and recreation sites, chiefly due
to their proximity to Adelaide and coastal
outlook. Popular activities include swimming,
surfing, boating, sailing, SCUBA diving,
visiting Granite Island to see the penguins,
whale watching during winter, visiting
historical sites and general sightseeing. It is a
particularly popular place for retirees and
families. The long expanses of beach are ideal
surfing and swimming areas, whilst the tall
cliffs at Tunk Head allow for spectacular hang
gliding. There is one charter boat operator in
Victor Harbour.
−
The Bluff is also known as Rosetta Head.
This 100 m granite outcrop has good walking
trails and magnificent views of Encounter
Bay, Victor Harbour and the surrounding
countryside. The Bluff is one of the most
popular dive sites in South Australia. The
granite headland provides good reefal habitat
for a wide range of marine life, including,
lobsters, cuttlefish, seals and a wide range of
fish, including Weedy and Leafy Sea Dragons.
−
2.4
−
−
−
West Island itself is a Conservation Park
surrounded by an aquatic reserve (ie. West
Island Aquatic Reserve). The aquatic reserve
was established in 1966 specifically for
scientific research purposes, in order to protect
and study the resident Abalone population
(Haliotis sp). As such, research studies on this
species have continued for over 20 years and
have provided valuable information on the
population dynamics of this species.
In
addition to research on Abalone, scientific
studies have also examined the major benthic
communities around the island, in an attempt
to understand fundamental marine ecological
processes. A small field station is located on
the island, and this is used by a number of
postgraduate students, researchers, and
interstate and overseas visiting researchers.
No fishing is permitted within this area.
−
Rosetta Head (including Kings Beach and
Rosetta Bay) have been used regularly by
both, the University of Adelaide and Flinders
University, for the past 30-15 years as an area
for teaching marine biology. At Kings Beach,
the rocky shore and intertidal pools support a
diverse range of crustaceans, molluscs,
starfish, sea cucumbers, sea anemones and
other benthic organisms. This whole area has
suffered a substantial decline in the
populations of some of the species, especially
starfish and sea cucumbers (Dr. J. Orbach,
pers. comm.). As this area is not currently
protected, it is possible that people are
removing the organisms as souvenirs or food
items.
SCUBA diving: Rapid Head, the Bluff (Victor
Harbour), West Island (Victor Harbour), and
Blowhole Creek (Deep Creek Conservation
Park) are all popular diving locations in this
region and are all listed in `Dive South
Australia: The Best Dive Sites in South
Australia’ (Diving Industry Association of
South Australia.
Scientific Research and Education
The Botany Department of The University of
Adelaide has ongoing research into the
ecology of marine plant communities near the
Cape Jervis jetty.
The whole of the West Island, Seal Island,
Granite Island, and Rosetta Head region is one
of the most significant areas for marine
biological research in South Australia. This is
primarily because of the rich diversity of
marine habitats and its proximity to
metropolitan Adelaide. As such, many marine
research studies have been, and will continue
to be, undertaken in this important locality.
2.5
Adjacent Land Use
National and Conservation Parks
−
Deep Creek Conservation Park (4,228 ha).
−
Newland Head Conservation Park (1,036 ha).
−
West Island Conservation Park (18 ha),
includes Seal Island and the West Island
Aquatic Reserve (65 ha) (SANPWS 1983).
−
Granite Island Recreation Park.
−
Pullen Island Conservation Park (SANPWS
1983).
Page 196
GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – ENCOUNTER BIOUNIT
whaling company arrived.
The industry
flourished until the 1860's. In 1839, the first
settlers arrived under the leadership of
Reverend Ridgeway Newland.
Victor
Harbour and Port Elliot soon became
important ports.
However, after many
shipwrecks and the extension of the railway to
Victor Harbour, Port Elliot's days as a
shipping port ceased. Victor Harbour declined
as a predominant port when river trade was
diverted directly to Adelaide, and the towns
became tourist resorts.
Agriculture/Industry
−
Areas not set aside for conservation parks in
this biounit have generally been cleared of
native vegetation and used for agriculture and
grazing, or for urban development.
−
Major sources of marine pollution in this
biounit include: outlets at Hindmarsh River,
Inman River (also a sewage outlet) and
Watson Gap.
Urban Centres
−
Victor Harbour (population , 318).
−
Goolwa (population 2,360).
2.6
Features
−
There are historic sites along the foreshore
between Rosetta Head and south Goolwa
associated with early settlement of the area.
−
Cape Jervis is also a significant site for
European history as it was named by Matthew
Flinders is 1802 and a whaling industry
established during the 1840's, continuing until
1855. The town is also the site of a lighthouse
established in 1871.
Significant Cultural and Historical
Aboriginal
Shipwrecks
−
−
The Aboriginal group occupying the
Encounter Bay area at the time of European
settlement of South Australia were the
Ramindjeri people. According to Aboriginal
legend, Granite Island and West Island feature
in the legend of the great totemic being
Ngurunderi. He was responsible for making
these islands and other features during his
Dreamtime journey down the Murray Valley
in pursuit of his two unfaithful wives.
Aboriginal sites at Waitpinga cover
approximatley 20 ha, and are on the Register
of the National Estate (Bilney et al, 1981,
cited by Baker and Edyvane, 1996). The sites
comprise campsites, Kartan tools, hearths and
shell middens. at other Aboriginal sites at
Cape Jervis, large pebble and block Kartan
tools are indication sof some of the earliest
Aboriginal occupation on the Fleurieu
Peninsula (Ross, 1984, cited by Baker and
Edyvane, 1996). On King’s Beach exists a
natural sandtrap, which was made and used by
the Ramindjeri living in Encounter bay
(Shepherd, pers. comm. cited by Baker and
Edyvane, 1996).
−
Encounter Bay was the site of the earliest
shipwreck the `South Australian' in 1837.
−
The historic shipwreck `Victoria’ lies off
Tunkalilla Beach.
−
`Solway' in 1837 was built in Britain and was
wrecked near Victor Harbour whilst
transporting German immigrants to Adelaide.
The wreck is located on a sandy patch 150
metres inshore from the face of Blacks Reef in
3-4 metres of water.
−
`Harry', built at Dorset, United Kingdom in
1842 and wrecked near Port Elliot in 1856.
The remains of this vessel are located in 3-4
metres of water near Commodore Point and
are an excellent example of wooden ship
construction from the 1840's.
−
A total of seven other ships were wrecked in
Horseshoe Bay, Port Elliot between 1853 and
1864.
European
−
The Encounter Bay area is an important area
for European History in South Australia. It
was so named by Captain Matthew Flinders
after he met the French navigator Baudin here
in 1802. The first settlement at Encounter Bay
occurred in 1837 when the Robert Campbell
Page 197
GULF OF ST VINCENT – FLEURIEU PENINSULA REGION – ENCOUNTER BIOUNIT
3
CURRENT CONSERVATION STATUS
OF THE ENCOUNTER BIOUNIT
−
Marine Reserves
West Island Aquatic Reserve (65 ha)
−
Marine Parks
None
−
Encounter Bay 42
−
Netting Closures
Parson's Beach (north of a line from the
eastern end of the beach to the western end).
−
Waitpinga Beach (north of a line from
Newland Head to the western end of the
Waitpinga Beach)
−
Hindmarsh and Inman Rivers (the waters of
Hindmarsh and Inman Rivers and within 200
m of their mouths).
4
AREAS OF HIGH CONSERVATION
VALUE IN THE ENCOUNTER BIOUNIT
Deep Creek - Newland Head
−
Prime
IUCN
Conservation
Values:
biodiversity,
rare
and
endangered
species/habitats, social values (IUCN Category
II). IUCN Identification Criteria: naturalness
(not subjected to human-induced change),
biogeographic (`geological monuments'-Deep
Creek, Tunkalilla Beach), ecological (range of
coastal marine habitats, reefs, estuaries-Tent
Rock Creek, `endangered' Leafy Sea Dragon,
reef fish populations), economic (marine
scalefish fisheries-King George Whiting, Shark,
Calamari, Snapper, Salmon, Mullet), social
(aboriginal significance-Waitpinga Beach,
recreation, historic shipwrecks- `Victoria’),
scientific
(marine
biological
research/monitoring at Cape Jervis region),
national (Register of the National Estate-Deep
Creek, Newland Head Conservation Parks,
Waitpinga Beach), practicality (insulation,
accessibility,
compatibility-Deep
Creek,
Newland Head Conservation Park).
Prime IUCN Conservation Values: rare and
endangered
species/habitats,
biodiversity,
cultural, social values (IUCN Category II).
IUCN Identification Criteria: biogeographic
(representativeness, wide range of geological
features,
`geological
monuments'-entire
Encounter Bay region, Middleton Beach,
Encounter Bay), ecological (range of coastal
marine habitats, reefs, seagrass meadows,
estuaries-Inman River, Hindmarsh River,
islands, `endangered species'-Leafy Sea
Dragon, Southern Right Whale, `rare'
Australian Sea Lion, seabird breeding coloniesLittle Penguins, Crested Terns, Caspian Terns,
Little Terns, Silver Gulls, White-breasted Sea
Eagles, Little Falcons, numerous coastal
wading birds), economic (marine scalefishShark, Calamari, Snapper, Snook, Australian
Salmon, Abalone, tourism-diving, fishing,
boating), social (recreation, education-Whale
Watch Centre, penguin watching, Rosetta Head,
historic shipwrecks-`Solway', `Harry', `South
Australian', aboriginal fish traps-Kings Beach,
aboriginal sites-Middleton, Sir Richard
Peninsula), scientific (marine biological
research/teaching-Rosetta Head, West Island,
Granite Island), national (Register of the
National Estate-Rosetta Head, Wright Island,
Granite Island, Seal Island), practicality
(accessibility, compatibility –adjacent to West
Island Aquatic Reserve/Conservation Park).
Pages Conservation Park
−
Prime IUCN Conservation Values: rare and
endangered
species/habitats,
research,
biodiversity (IUCN Category IA). IUCN
Identification Criteria: naturalness (not
subjected
to
human-induced
change),
biogeographic
(representative
marine
habitats, global importance for Australian Sea
Lions), ecological (largest breeding colony of
`rare' Australian Sea Lion in the world,
spawning area-Snapper, Western King Prawn,
high marine biodiversity-sponge gardens,
brachiopod diversity), economic (marine
scalefish-Shark, Calamari, Snapper, Snook,
Australian Salmon, Southern Rock Lobster),
scientific (research/monitoring-Australian Sea
Lions), national (potential for listing on the
Register of the National Estate), practicality
(insulation,
accessibility,
compatibilityadjacent to Pages Conservation Park).
42
The Encounter Bay region was formally nominated for
conservation management as an Aquatic Reserve by Halstead
(1987).
Page 198
KANGAROO ISLAND COAST
MARINE BIOGEOGRAPHY AND CONSERVATION VALUES OF
THE KANGAROO ISLAND COAST
MARINE BIOGEOGRAPHY
1.
2.
3.
4.
5.
Kangaroo Island
Oceanography
Climate
Geology and Coastal Geomorphology
Biology
MARINE CONSERVATION VALUES
1.
2.
3.
Significant biological and Physical Features
Significant Cultural and Historical Features
Current Conservation Status of the Kangaroo Island Coast
BIOUNITS
1. Nepean and Backstairs
2. Gantheaume
3. Cassini
Page 199
KANGAROO ISLAND COAST
MARINE BIOGEOGRAPHY AND CONSERVATION VALUES OF
THE KANGAROO ISLAND COAST
MARINE BIOGEOGRAPHY
1
KANGAROO ISLAND
Kangaroo Island, off the southern coast of Fleurieu
Peninsula, South Australia, is Australia's third largest
Australian isle (following Melville Island and
Tasmania). The island encompasses some of South
Australia's most popular tourist destinations (such as
Seal Bay and American River) and is well-known for
its spectacular coastline and coastal wilderness areas
(such as the Flinders Chase National Park). The
island currently contains all 5 of South Australia’s
wilderness areas declared under the Wilderness
Protection Act 1992. Kangaroo Island (along with
the Pages Islands in Backstairs Passage), is also a
region of considerable conservation significance for
marine fauna and flora, particular mammals, and
includes not only major breeding areas for the rare
Australian Sea Lion and the New Zealand Fur Seal,
but also areas which are regularly frequented by the
endangered Southern Right Whale on their northward
migration to the calving and breeding areas at the
Head of the Great Australia Bight (Inns et al. 1979).
Historically, the rugged southern and western coast
of Kangaroo Island also comprises some of the major
sites of maritime significance in South Australia.
The latter, containing an unusual concentration and
density of shipwrecks of high cultural value.
Kangaroo Island is also characterised by a wide range
of coastal landforms from the sheltered tidaldominated coastal lagoons on the northeast coast (eg.
Pelican lagoon, American River inlet), to spectacular
wave-exposed coastal cliffs along the south coast
(such as Cape de Couedic). The island itself has a
strong influence on the oceanography, and thus
geomorphology, of the South Australian coastline,
particularly the Gulf St Vincent Bioregion. Situated
at the head of Gulf St Vincent, the large island
essentially shelters the adjacent mainland coastal
regions from the high wave energies of the Southern
Ocean.
1.1
Biogeography of Kangaroo Island
Along the southern coast of Australia, marine
biogeographers recognise a major biogeographic
region, known as the Flindersian Province, which
extends from southwest Western Australia to
southern New South Wales and includes the waters
of Victoria and Tasmania. Within this broad region,
the coastal waters of the Great Australian Bight (west
of Robe) are recognised as warm to cool temperate
(in contrast to the cold temperate waters of the
southeast of Australia, east of Robe).
Within the Flindersian Province, the Kangaroo Island
coastal and marine ecosystems encompass 2 welldefined biogeographical regions known as the Gulf
St Vincent Bioregion and the Eyre Bioregion. The
north coasts of Kangaroo Island encompass the Gulf
St Vincent Bioregion, which extends from West
Cape to Cape Borda (Kangaroo Island), and from
Cape Jervis to Cape Willoughby (IMCRA 1997).
However, the southern and western coast of
Kangaroo Island, from Cape Borda to Cape
Willoughby,
falls
within
another
marine
biogeographic known as the Eyre Bioregion, which
extends from Cape Bauer to Cape Borda, to West
Cape, to Port Neill and Cape Willoughby (IMCRA
1997).
A complete physical and ecological
biogeographic description of the Gulf St Vincent
Bioregion and also, the Coorong Bioregion, including
marine fauna and flora, has been described by
IMCRA (1997).
Based on coastal geology, wave climate, and coastal
orientation, Short and Fotheringham (1986),
identified three coastal geomorphological regions (or
subprovinces) for the Kangaroo Island coast:
1.
2.
3.
Northern Coast Subprovince (from Cape Borda
to North Cape, 111 km)
North-Eastern Coast Subprovince (from North
Cape to Cape Willoughby, 114 km)
Southern and Western Coast Subprovince
(from Cape Willoughby to Cape Borda, 232
km)
Page 200
KANGAROO ISLAND COAST
These coastal subprovinces correspond to 3 finerscale marine biogeographical regions or biounits:
1
2
3
2
2.1
Cassini Biounit (from Cape Borda to North
Cape, 111 km)
Gantheaume Biounit (from North Cape to
Cape Willoughby, 114 km)
Nepean Biounit (from Cape Willoughby to
Cape Borda, 232 km)
OCEANOGRAPHY
Wave Climate
The western and southern coasts of Kangaroo Island
have a distinct cool-temperate climate. Most of this
coastal region is fully exposed, almost year round, to
strong prevailing winds (from the south and west)
and the Southern Ocean, which result in moderate to
high energy, south west to westerly swells and surge
conditions. Areas along the more exposed regions of
this coast (eg. Cape du Couedic, Cape Borda and
Cape Willoughby), show a persistent year round
southwest to westerly swell of 2-4 m for
approximately 50% of the year. This swell is most
persistent from March to October, but decreases
slightly in occurrence between November and
February. Lower wave energy areas occur only in
the east-facing D’Estrees Bay. In contrast, the north
coast of Kangaroo Island has a predominantly low
wave energy regime. This is due principally to its
sheltered northern aspect. The calmest part of the
north coast of Kangaroo Island is the almost landlocked area of American River inlet. Here wave
action is almost negligible on the tidal flats except
when strong winds blow across the lagoons.
The tides in this province are typical for South
Australian waters, ie. they are a `mixed' type,
comprising both a semi-diurnal (ie. two high tides
and two low tides daily), and a diurnal (one high tide
and one low tide daily) phase. `Dodge tides' or
periods of minimal semi-diurnal tidal movement,
occur during neap periods on the northern side of
Kangaroo Island and around the American River inlet
region. During this time, only one tide per 24 hr
occurs over 2-4 days in the neap period, but two tides
of less amplitude may occur. When the single tide
occurs, the low level is usually lower than tides
before and after, while the high may be nearly as high
as some spring tides. The neap period varies from a
day before the first and third quarters of the moon to
4 or 5 days after.
Tides are of relatively small amplitude and show
some variation from place to place. On the
exposed coasts of this province, the spring range is
approximately 0.8-1.3 m, increasing to 1.3-1.7 m
on the north coast of Kangaroo Island. The height
of the tide may be greatly modified by winds. On
exposed coasts, a strong offshore wind generally
keeps the sea-level down. Mean sea-level, and
other tidal means, are highest during winter and
lowest during summer months, the difference being
as much as 15-20 cm. January-February is the
period of the lowest sea-level and thus the lowest
tides. In general, the lower of the two daily low
tides occurs during the middle of the day in
summer (October-April) and in the middle of the
night in winter (June-September). The higher of
the two daily low tides occurs in the early hours of
the morning during summer, and in the afternoon
during the winter. The lower of the high tides is
the opposite of this.
2.2
Water Temperature and Salinity
Offshore sea surface temperatures along the
Kangaroo Island coast are typical for the western and
central coasts of southern Australia, ranging from
mean sea surface temperatures of approximately 1820oC in summer to 14-16oC in winter. Inshore
temperature variations, particularly in sheltered bays
and inlets, are generally much greater. Temperature
anomalies may also arise from the deep water
submarine canyons located 60 km south of the
Kangaroo Island.
On the shallow, sheltered,
northeastern coast of Kangaroo Island, the depth of
water and degree of wave action causes a greater
temperature range. For instance, on the tidal flats of
American River inlet, water temperatures range from
320C to 100C. In the Vivonne Bay area, isolated rock
pool temperatures of 30 to 400C are frequent in
summer.
The salinity of the waters in Backstairs Passage and
around Kangaroo Island and Encounter Bay is
relatively uniform (35.5%. to 36%.). However, slight
salinity increases do occur in the sheltered lagoons of
Kangaroo Island during summer.
2.3
Currents and Upwellings
A surface current flows from west to east along both
sides of Kangaroo Island and is strongest in the
period from May to July. The currents in Backstairs
Passage are largely tidal and dominate the northern
part of the coastline.
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KANGAROO ISLAND COAST
The inshore regions of the northwest coast of
Kangaroo Island are under the influence of seasonal
coldwater, nutrient-rich coastal upwellings which
occur close to the coast, and can result in an offshore
sea surface temperature gradient of 18oC to inshore
temperatures of 11oC in inshore areas during the
summer months. The major focus of the coastal
upwelling extends from Point Sir Isaac (Coffin Bay
Peninsula) to Cape Borda (Kangaroo Island) (Wenju
et al. 1990), and is responsible for the very high
levels of productivity and pilchard abundance in the
region (Ward & McLeay 1998), and may be linked to
the abundance of seabirds, marine mammals, and
high levels of marine benthic biodiversity in the
region.
Geologically, Kangaroo Island is an extension of the
most southerly part of the Mt Lofty Ranges known as
Fleurieu Peninsula, but separated from it by the
waters of Backstairs Passage (Daily et al. 1979). As
such, the southern Fleurieu Peninsula, from Cape
Jervis to the mouth of Murray River, is
geomorphologically very similar to the Kangaroo
Island coast and hence, is considered a part of the
Kangaroo Island Province.
The coastal
geomorphology of Kangaroo Island has been
extensively studied (see Short & Fotheringham 1986)
and is detailed below under the relevant biounits.
3
5.1
CLIMATE
5
BIOLOGY
General Ecology
The climate of Kangaroo Island and southern
Fleurieu Peninsula is typically `cool temperate', with
a distinct winter rainfall maximum, but with
relatively mild conditions during summer and winter.
The main influences on the climate of this region are
the prevailing mid-latitude anticyclones or high
pressure systems, and the moderating effect of the
surrounding ocean.
The biology of Kangaroo Island, and particularly it’s
marine component, has long been recognised by
marine biologists as one of the richest and most
fascinating biotas of the southern Australian coasts:
4
This richness is partly due to the great variety of
coastal habitats provided by the island (Womersley &
Edmonds 1979). These marine habitats include:
exposed rocky shores, estuaries and tidal flats, sandy
beaches, protected bays, open ocean surf zones, reefs,
islands and offshore submarine canyons.
GEOLOGY
AND
GEOMORPHOLOGY 43
COASTAL
Kangaroo Island is primarily composed of folded
Precambrian and Cambrian metasediments of the
Adelaide Geosyncline series. These metasediments
are exposed at many locations along the coast.
Igneous rocks of Cambrian, Permo-Carboniferous
rocks of glacial origin, marine Tertiary and marine
Quaternary are also exposed along the coast. Beach
and aeolian sediments of Pleistocene and Holocene
Epochs occur along the coast and particularly along
the south and west coasts.
The overall outline and much of the detailed
shoreline configuration of Kangaroo Island is
controlled by the pre-Quaternary bedrock geology
and denudation. Under various sea levels the
bedrock has been attacked to form sea cliffs and large
amounts of carbonate shell detritus from the inner
shelf has been moved through beaches to form
massive dune systems along the south and west
coasts. These systems have in turn been lithified
during low sea levels which are then eroded during
higher sea levels to form calcarenite sea cliffs.
Elsewhere the seas have reworked terrigenous
material along the north and northeast coasts where
they form generally low energy beach and tidal flat
deposits. The pre-Quaternary bedrock geology and
Tertiary denudation dominates the gross morphology
of the entire Island.
43
From Kangaroo Island Coast Protection District Study Report
(Edwards 1987).
"...a thorough analysis may well show that the
diversity of marine life is as great or even
greater than on the Great Barrier Reef.”
(Womersley & Edmonds 1979).
The intertidal coast of Kangaroo Island is similar to
the central and western coasts of South Australia
(Womersley & Edmonds 1958). In the supralittoral
Littorina unifasciata is dominant (except where
conditions are very calm) and at high levels on very
exposed coasts Calothrix fasciculata is found. The
littoral zone, where the coast is most exposed,
consists of barnacles - Chthamalus antennatus and
Chamaesipho columna in the upper littoral,
Catophragmus polymerus in the mid littoral, and
Balanus nigrescens in the lower littoral - but where
the coast is more sheltered it consists of molluscs in
the upper and mid littoral and algae (Corallina
cuvieri, Gelidium pusillum, or Hormosira banksii) in
the lower littoral. In the upper sublittoral fucoid
algae or in calm regions, marine angiosperms, are
dominant.
Womersley & Edmonds (1979), in their account of
the intertidal ecology of Kangaroo Island, described 3
distinct regions: (i) coasts subject to strong wave
action (ie. south and west coasts, extending along the
north coast to approximately Western River; (ii)
coasts subject to moderate wave exposure (ie. most of
the north coast); and (iii) protected coasts with no or
little wave action and sandy-mud tidal flats (ie.
American River inlet).
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KANGAROO ISLAND COAST
The marine benthic flora of Kangaroo Island is
extremely rich and diverse and includes over half of
the species found in southern Australia (Womersley
& Edmonds 1979). Rocky coasts are dominated by
algae and in sheltered coastal waters and estuaries,
seagrasses are dominant. Five genera of seagrasses,
plus two normally brackish water angiosperms
(Ruppia and Lepilaena) and approximately 500-600
species of marine algae have been recorded from the
coastal waters. These include the brown algae
Cystophora intermedia which occupies the sublittoral
fringe where strong wave action occurs. In more
sheltered areas it is replaced by other species of
Cystophora or Ecklonia radiata.
Sand and sandy mud formations (eg. American River
tidal inlet), are dominated by extensive seagrass
meadows, dominated by species of Posidonia and
Zostera.
5.2
Subtidal Ecology 44
5.2.1
Strong Wave Action Coasts
The southern and western coasts of Kangaroo Island
are characterised by strong wave action, steeply
sloping coasts of Palaeozoic rock (ie. granite,
gneisses) which form most of the headlands,
interspersed with horizontal calcareous platforms,
and sandy beaches. In zonation, the steeply sloping
Palaeozoic rocky coasts of southern and western
coast of the island are similar to Point Sinclair, Cape
Carnot (western Eyre Peninsula) (Womersley &
Edmonds 1958). The sublittoral fringe on the rocky
coasts are typically dominated by Cystophora
intermedia, while the sublittoral is dominated by
species of Cystophora, and Sargassum and red algae.
On calcareous reefs in particular, the kelp Ecklonia
radiata, numerous species of fucalean algae (ie.
Cystophora,
Sargassum,
Myriodesma,
and
Scytothalia), and a great variety of red algae occur
(Womersley & Edmonds 1979).
Within the sublittoral, the following zones have been
recognised: upper sublittoral zone: dominated by a
turf of Corallina cuvieri, with Cystophora intermedia
and Balanus barnacles, Gelidium glandulaefolium
and Curdiea gymnogongroides, Melanthalia spp.,
Sargassum spp. and Zonaria sinclairii; the mid
sublittoral zone: dominated by Ecklonia radiata and
other brown algae (Scytothalia dorycarpa,
Acrocarpia paniculata, Cystophora spp. and
Myriodesma spp.), and Melanthalia; and the lower
eulittoral zone: lies below the zone of larger brown
algae and consists of a dense cover of diverse red
algae, including especially species of Plocamium
(Womersley 1990). The fauna becomes more
prominent as the limits of the photic zone are
approached.
44
From Edyvane KS & JL Baker (1996). Marine Biogeography of
Kangaroo Island.
5.2.2
Moderate Wave Action Coasts
The northern coast of Kangaroo Island is
characterised by rocky sheltered coasts of moderate
wave action, interspersed with sandy beaches. In
zonation, the moderately sheltered coasts of the north
coast are similar to the southern parts of Gulf St
Vincent (Womersely & Edmonds 1958).
On rocky coasts subject to some wave action, the
upper sublittoral zone is typically dominated by
larger brown algae, especially Ecklonia radiata,
Cystophora subfarcinata, C.retorta, C.polycystidea,
C.moniliformis and other species, Caulocystis
cephalornithos,
Cystophyllum
onustum
and
Sargassum spp. (such as S.decipiens, S.lacerifolium),
with an understorey of coralline algae (for eg.
Amphiroa
anceps,
Cheilosporum
elegans),
Cladostephus spongiosus and often species of
Caulerpa (Womersley 1990).
On sandy bottom below rocky areas the seagrasses
Amphibolis and Posidonia often cover very extensive
areas as dense, often pure, communities.
Aeolianite dunes along the north coast of Kangaroo
Island form prominent sea floor eminences and a
rough bottom topography. This provides an excellent
substrate for a rich variety of benthic organisms such
as algae, sponges, crinoids and reef molluscs. A
varied fish population including excellent Southern
Rock Lobster and Snapper grounds are also found in
these habitats (Shepherd & Sprigg 1976).
5.2.3
Coasts of Slight Wave Action
The coast of north-eastern Kangaroo Island
comprises coasts of slight wave action, with sandy or
muddy flats or beaches, comprising almost landlocked bays, such as American River inlet. The
intertidal and subtidal ecology of American River
inlet has been well described by Womersely (1956).
The lower eulilttoral zone of American River inlet is
dominated by Hormosira banksii (Sea Grapes or
Neptunes Necklace) which is usually growing on the
large mussel Austromytilus erosuss.
Mats of
Chaetomorpha and other small algae may occur here.
Fauna includes the starfishes Patiriella exigua and
Uniophora. In the upper sublittoral zone there is a
marked change to a seagrass dominated habitat.
Species of green and red algae are common in the
uppermost sublittoral zone. Heterozostera is found
just above low tide level to 2 m deep and Posidonia
covers extensive areas of the flats below low tide
level. Halophilia is found along the edge of the
channel or in deeper areas. Large plants of the brown
algae Sargassum biforme and Scaberia occur in the
channel, usually attached to submerged boulders or
rocks. Epiphytic algae is found on Posidonia
(Womersley 1956).
Fauna include sponges,
starfishes, anemones, holothurian, polychaetes and
Page 203
KANGAROO ISLAND COAST
the razor fish Pinna. Fish species include sting rays,
eagle ray and small sharks (Womersley & Edmonds
1979). American River is also a known nursery area
for King George Whiting (Sillaginodes punctatus)
and an extensive feeding area for aquatic birds.
On the sheltered coasts in this region, seagrass beds
are generally well developed on sandy-muddy areas
of tidal flats, extending several metres deep.
Heterozostera tasmanica forms dense and pure
masses in thick, firm mud from low tide level down
for 3-4 m, with occasional plants as deep as 20m
(Womersley 1990). Posidonia (tapeweed) extends
large distances from about 0.5m below low tide to
20m or so deep. P.australis is the most widespread
species of tapeweed and it grows sympatrically with
P.sinuosa and P.angustifolia in the shallower part of
their range.
P.sinuosa is widely distributed to a depth of 15m in
sheltered bays and inlets, either in pure stands or
growing sympatrically with P.australis or
P.angustifolia.
In more exposed areas it may form meadows with
Amphibolis spp.. P.angustifolia grows subtidally
from 2-35 m deep. It frequently grows in deeper
water than P.australis. In its deeper range it is often
found in association with Heterozostera tasmanica or
Halophila australis and in sheltered positions in its
shallower range in association with Amphibolis
antarctica. The Posidonia leaves often carry a
wealth of epiphytes but only few macroalgae (for eg.
Caulerpa cactoides, C.remotifolia) occur in or
adjacent to the beds.
Common algae at and just below low tide level are
Hypnea musciformis, Spyridia filamentosa, Ulva
lactuca, Enteromorpha clathrata, Centroceras
clavulatum, Cladophora spp., and often Polyphysa
peniculus epiphytic on old cockle shells. Molluscs,
echinoderms, crustaceans and small fish are usually
common in this zone.
5.3
Fish
The fish fauna of the Kangaroo Island Province is
diverse but typical of the species found along the
southern coast of Australia. As such, the fish fauna
of this province falls within the biogeographical
province known as the Flindersian Province. Along
the inshore coastal waters and inland waters of
Kangaroo Island, some 231 known species of fish
have been recorded.
Seahorses, Seadragons), Gobiidae (Gobies),
Ophiclinidae
(Snake
Blennies),
Clinidae
(Weedfishes), Labridae (Parrot Fishes), Neoodacidae
(Weedy Whiting, Rock Whiting, Herring Cale),
Gobiesocidae (Clingfishes, Shore Eels) and
Monacanthidae (Leatherjackets).
5.4
Reptiles
A number of itinerant species of marine turtles have
been recorded along the Kangaroo Island coast.
These include, the Loggerhead Turtle (Caretta
caretta), Green Turtle (Chelonia mydas) and the
Leathery Turtle (Dermochelys coriacea) (Houston &
Tyler 1979).
5.5
Seabirds
Some 216 species of birds have been reported from
Kangaroo Island (Ford 1979). Seabirds include Little
Penguins (Eudyptula minor), four species of
cormorants, Black-faced Shags (Leucocarbo
fuscescens), and Silver and Pacific Gulls (Larus
novaehollandiae, L.pacificus). Caspian, Crested and
Fairy Terns (Hydroprogne caspia, Sterna bergii,
S.nereis) are present throughout the year and all
probably breed on the island. In winter, albatrosses
such as the
Yellow-nosed (Diomedea
chlororhynchos) or Black-browed (D.melanophrys)
are seen. The Wandering (D.exulans), Grey-headed
(D.chrysostoma) and Shy Albatrosses (D.cauta) have
also been recorded on the island.
5.6
Marine Mammals
Two species of pinniped breed in this region: the rare
Australian Sea Lion (Neophoca cinerea) and the New
Zealand Fur Seal (Arctocephalus forsteri). Of
particular significance in this region is the Pages in
Backstairs Passage, which comprise the largest
breeding colony for sea lions in Australia (and the
world). In this region, breeding colonies occur on
North Pages Island (310 pups, estimated population
1,491), South Pages Island (260 pups, estimated
population 1,251) and the southern coast of Kangaroo
Island, particularly Seal Bay (180 pups, estimated
population 866).
Such diversity, over a relatively small geographic
range, is in part due to the wide variety of aquatic
habitats found along the island's extensive coastline,
and also, the island's close proximity to the South
Australian mainland (Glover 1979).
Well represented taxonomic groups include the
families, Sygnathidae (Pipefishes, Pipehorses,
Page 204
KANGAROO ISLAND COAST
Together, the Pages and the south coast of the
Kangaroo Island comprise two of the three major
breeding sites for the rare Australian Sea Lion in
South Australia (Robinson & Dennis 1988, Gales et
al. 1994), and represent 30% of the Australian or
world population of 12,400 for this species (Gales et
al. 1994).
The southern and western coasts of Kangaroo Island
comprise the second largest breeding area for New
Zealand Fur Seals in South Australia (after the
Neptune Isles). Major breeding sites for fur seals
occur at Cape Gantheaume (525 pups, estimated
population 2,573), North Casuarina (442 pups,
estimated population 2166) and Cape du Couedic
(477 pups, estimated population 2,337) (Robinson &
Dennis 1988, Shaughnessy et al. 1994). Together,
these colonies comprise an estimated 7076
individuals, representing some of the major breeding
sites for Fur Seals in South Australia (ie. 26% of the
SA population), along with the Neptune Islands
(estimated population of 16,886) and Liguanea Island
(estimated population of 2,720).
Several species of whales frequent the waters around
Kangaroo Island and Encounter Bay, and strandings
also occur occasionally. In particular, the endangered
Southern Right Whale (Eubalaena australis) appears
regularly in the winter months during its northward
migration from Tasmanian waters to the waters at the
Head of the Great Australian Bight.
Along
Encounter Bay in particular, the whales can be easily
from shore.
MARINE CONSERVATION VALUES
1
1.1
SIGNIFICANT
BIOLOGICAL
PHYSICAL FEATURES
AND
Biological
Backstairs Passage
The Backstairs Passage region is unparalleled in
it’s diversity of marine invertebrate assemblages
and is one of the richest areas for sessile
invertebrate fauna in South Australia (Dr Scoresby
Shepherd, SARDI, pers.comm.). Strong current
flows in the narrow Passage provide optimal
conditions for filter-feeding organisms and many
organisms, particularly sponges and bryozoans,
reach very large proportions and also, importantly,
outcompete plant communities in colonising
shallow reefal areas in high current regions.
The deep water (ie. 75 m) sessile invertebrate fauna
of the Passage is of national importance with regard
to the diversity of brachiopods (Dr Scoresby
Shepherd, SARDI, pers.comm.), and possibly,
global importance if records of stalked crinoids by
the SA Museum (ie. Dr J Mitchell) are confirmed.
The Snapper Point region (including Cable Hut
Bay) is of particular significance within Backstairs
Passage. Reef communities extend from the
shoreline out to 500-700 from the rocky headlands
and form habitat for a diverse, shallow water,
animal-dominated community (ie. 15 metres and
deeper) which is usually found in much deeper
waters (50-70 metres). Within the Passage, this
community is found in a rocky channel at 75m.
This is the first shallow water record of this rich,
deep water sessile marine invertebrate community
in South Australia, and is also the only recorded
site in South Australia where this community type
is accessible on SCUBA. The community is
characterised by very large filter-feeding
organisms, particularly very large sponge,
bryozoans and crinoid assemblages. The region
which contains these assemblages appears to be
restricted to the southern part of the Backstairs
Passage (ie. the Kangaroo Island coast). The
shallow
water,
sponge-bryozoan-crinoid
community is highly localised within the southernwestern part of the Passage (ie. Snapper Point
region).
Australian Sea Lions - Seal Bay
Seal Bay is an important area for a large breeding
colony of the rare Australian Sea Lion.
Its
importance is reflected by its status as both a
conservation park and an aquatic reserve. It is also
one of the major tourist destinations on Kangaroo
Island, and for South Australia. The south coast of
the Kangaroo Island, particularly Seal Bay,
comprises the third largest breeding area for the rare
Australian Sea Lion in South Australia, after the
Pages and Dangerous Reef (Robinson & Dennis
1988, Gales et al. 1994). The population on the
southern coast of Kangaroo Island, particularly Seal
Bay, is estimated at 866 (ie. 180 pups), and represents
a significant proportion of the estimated Australian or
world population of 12,400 for this species (Gales et
al. 1994). A total of 331 adults and 156 pups were
recorded at Seal Bay in 1977 (Robinson & Dennis
1988), while 427 adults and 162 pups were recorded
in 1990 (Gales 1990).
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KANGAROO ISLAND COAST
Coastal Wetlands of National Importance
New Zealand Fur Seals – Cape Gantheaume,
Cape du Couedic, North Casuarina
The southern and western coasts of Kangaroo Island
comprise the second largest breeding area for New
Zealand Fur Seals in South Australia (after the
Neptune Isles). Major breeding sites for fur seals
occur at Cape Gantheaume (525 pups, estimated
population 2,573), North Casuarina (442 pups,
estimated population 2,166) and Cape du Couedic
(477 pups, estimated population 2,337) (Robinson &
Dennis 1988, Shaughnessy et al. 1994). Together,
these colonies comprise an estimated 7,076
individuals, representing some of the largest breeding
sites for Fur Seals in South Australia (ie. 26% of the
SA population), and Australia, along with the
Neptune Islands (estimated population of 16,886) and
Liguanea Island (estimated population of 2,720).
A Directory of Important Wetlands in Australia
(ANCA 1996) list the following coastal wetlands of
national importance along the Kangaroo Island
Coast:
1
2
3
4
5
6
7
8
American River Wetland System
Busby and Beatrice Islets
Cygnet Estuary
D’Estrees Bay
Flinders Chase River Systems (NW River,
Breckneck River, Rocky River)
Grassdale Lagoons (SW River)
Lake Ada
Lashmar
Lagoon
(Chapman
River,
Antechamber Bay)
Encounter Bay
Pages Conservation Park
The Pages represent the largest breeding colonies
of the rare Australian Sea Lion in South Australia,
and the world. The Pages consists of two small
islands and a rocky reef in Backstairs Passage.
Breeding colonies occur on North Pages Island
(310 pups, estimated population 1,491) and South
Pages Island (260 pups, estimated population
1,250) (Gales et al. 1994).
Together, these
comprise a major proportion of the Australian (and
world)
population
(estimated
at
12,400
individuals). In 1990, 595 sea lions (including 280
pups) were recorded on North Page, 417 seals (242
pups) on South Page, and 140 were recorded on
SW Pages Reef, which is a recognised haul out site
(Gales 1990). Metamorphosis of the sediments
deposited during the latter part of the Cambrian
Period produced phyllite rock of the Brukunga
Formation, which now forms the rock of the
islands. North Page (24 m high) and South Page
(20 m high) are the two main islands and both have
precipitous slopes and deep chasms. The tops of
the islands are relatively flat with small soil
pockets. The islands can be considered remote and
the only reliable means of access is by helicopter.
The islands feature in the Kaurna Aboriginal
legend which describes the journey of the totemic
being Ngurunderi as he pursued his unfaithful
wives. Upon catching them he transformed them
into the islands. A reed basket carried by the
younger wife was transformed into a nearby reef.
The Pages is an important area for sea birds and
seals - a fact recognised by their declaration as part
of a Bird Protection District under the Birds
Protection Act in 1900. The Pages Conservation
Park (20 ha) is now under the control of the
National Parks and Wildlife Service.
−
Macroalgae assemblages, Whales, Little
Penguins, Leafy Seadragons, Seabirds,
Hemichordates.
Coastal Wilderness Areas
The Kangaroo Island coast has some of the most
spectacular coastal wilderness and visual amenity
along the South Australia coast, and is home to all 5
of South Australia’s Wilderness Protection Areas,
declared under the Wilderness Protection Act 1992
(to protect natural and remote wilderness areas).
These areas include:
−
Cape Bouguer Wilderness Protection Area
(5,530 ha).
−
Cape Gantheaume Wilderness Protection Area
(20 100 ha).
−
Cape Torrens Wilderness Protection Area (751
ha).
−
Ravine des Casoars Wilderness Protection
Area (41,320 ha).
−
Western River Wilderness Protection Area
(2,373 ha).
Page 206
KANGAROO ISLAND COAST
1.2
Physical
2
Murray Submarine Canyons
The Murray Submarine Canyons are giant submarine
canyons 60 km south of southern Kangaroo Island.
Some of these huge clefts are larger than the Grand
Canyon in the U.S.A. They wind their way from the
outer continental shelf to oceanic depths of
approximately 4,600 m. They may be important as a
valuable source of upwelling water which contributes
to the nutrients of the food chain (Von der Borch
1979). The sediments of the canyon walls could also
contain a record of the major geological changes that
occurred during the evolution of the South Australian
continental margin. GLORIA sidescan sonar images
reveal steep, rugged topography that would probably
contain some unique, little known ecosystems (Von
der Borch pers. comm.).
"Geological Monuments”
There are 16 areas of geological significance on
Kangaroo Island which are associated with the
coastline or offshore waters. These areas have been
identified and recognised as "geological monuments"
by the South Australian Museum and the Geological
Society of Australia, and include the following sites:
1.
Kingscote (foreshore)
2.
Old Government Quarry, Kingscote
3.
The Big Gully
4.
Emu Bay (Cape D'Estaing)
5.
Smith Bay (glacial pavements)
6.
Stokes Bay
7.
Harveys Return
8.
West Bay
9.
Cape du Couedic
10. Remarkable Rocks
11.
Point Ellen, Vivonne Bay
12.
Cape Willoughby (granite contact)
13.
Alex Lookout to Snapper Point
14.
Christmas Cove, Penneshaw
15.
Willson River
16.
D'Estrees Bay
In addition, Ravine des Casoars is also considered to
be a significant geological site.45
Further details of these areas are supplied in the
relevant biounit sections below.
SIGNIFICANT
CULTURAL
HISTORICAL FEATURES
AND
The following description of Aboriginal and
European history along the Kangaroo Island coast is
necessarily brief and selective. The aim is to give the
province a historical perspective with emphasis on
coastal and maritime history. Only details of
Aboriginal historical and cultural sites that have been
published in the available literature are described.
Aboriginal sites, objects and remains are protected
under the South Australian Aboriginal Heritage Act
(1988), and a register of such sites, objects and
remains is kept with the Aboriginal Heritage Branch
of the South Australian Department of Environment
and Planning.
2.1
Aboriginal
At the time of its discovery by Europeans, Kangaroo
Island
was
uninhabited
by
Aborigines.
Archaeological sites show that Kangaroo Island was
occupied at several dates until as recently as 4,300
years ago. The geologist Howchin found the first
prehistoric stone tools near the shore of Murray
Lagoon in 1903. More hammer stones and cutting
pebbles were found by Tindale and Maegraith in
1931, and Tindale continued exploration until the
1960s. Over 100 sites were found, many containing
large numbers of massive stone tools made from
beach cobbles and blocks of stone. Tindale named
the stone industry `Kartan' after the Ramindjeri name
`Karta' for Kangaroo Island. Kangaroo Island was
known by the mainland Aboriginals as `Karta Island
of the Dead', because it is where Ngurunderi, the
great spirit ancestor, ended his long voyage down the
Murray River and along the South Coast in pursuit of
his unfaithful wives.
2.2
European
First Discoverers
Captain Matthew Flinders sighted Kangaroo Island in
1802, in what was probably the first European
sighting of the island. The name was chosen because
of the abundant kangaroos on the island that provided
the crew with fresh meat. The French navigator
Captain Nicolas Baudin was the first to
circumnavigate the island in 1802, just after Flinders'
visit. Following the voyages of Flinders and Baudin,
the island was occasionally inhabited by sealers,
whalers, escaped convicts and sailors seeking refuge.
Formal settlement became more definite in the early
1830's following the explorations by Captain Charles
Sturt and Captain Collett Barker, and in 1836 a
whaling settlement at Nepean Bay was established.
45
From Kangaroo Island Coast Protection District Study Report
(Edwards 1987).
Page 207
KANGAROO ISLAND COAST
The Encounter Bay area is a significant area for
European History in South Australia. As well as
being the site where Captain Matthew Flinders met
the French navigator Baudin in 1802, it was also a
site of early settlement and their first industy whaling. Cape Jervis is also a significant site for
European history and was also a site for the whaling
industry from the 1840's til 1855.
Shipwrecks
−
Marine Sanctuaries
None
−
−
−
−
Netting Closures
Kingscote Spit
Bay of Shoals
American River – Eastern Cove
Kangaroo Island Rivers
Wrecks in excess of 75 years old in Commonwealth
waters
are
automatically
protected
by
Commonwealth legislation, ie. Historic Shipwrecks
Act 1976. Other wrecks may be protected if of
significant value. Wrecks situated in State waters
may be protected by proclamation under the State
legislation, ie. Historic Shipwrecks Act 1981.
The rugged and precipitous coastline of Kangaroo
Island has claimed many ships with some 57 known
shipwrecks between 1847 and 1985.
Cape
Willoughby was the first lighthouse to be built in
South Australia in 1852. The west coast of Kangaroo
Island in particular, is an area of significant historical
and cultural value, due primarily to the number and
density of shipwrecks and the associated large loss of
life (B. Jefferies, State Heritage Branch, pers.comm.).
Significant wrecks in this area include the `Loch
Sloy', `Loch Vennachar', `Montebello', `Mars', `Emily
Smith' and `Portland Maru'.
3
CURRENT CONSERVATION STATUS
OF THE KANGAROO ISLAND COAST
As with the other coastal provinces of South
Australia, the majority of MPAs in this region
comprise `netting closures'. However, many of these
areas have generally not been formally recognised as
MPAs by some authors (see Ivanovici 1985). Three
Aquatic Reserves have been declared in this
province, two on Kangaroo Island and one in
Encounter Bay. No Marine Parks have been declared
in this region.
Present MPAs in this region include:
−
−
−
−
Marine Reserves
American River Aquatic Reserve (1,525 ha)
Seal Beach Aquatic Reserve (1,140 ha)
West Island Aquatic Reserve (65 ha)
(mainland)
Marine Parks
None
Page 208
KANGAROO ISLAND COAST – NEPEAN AND BACKSTAIRS BIOUNITS
XIV
MARINE BIOGEOGRAPHY AND CONSERVATION VALUES OF
NEPEAN AND BACKSTAIRS BIOUNITS
This coastal region comprises 2 biounits: the inshore coastal Nepean Biounit, and the offshore Backstairs
Biounit. The Nepean Biounit extends from North Cape to Cape Willoughby and covers an area of 102 304 ha
and a coastal distance of approximately 114 km. It faces into Backstairs Passage and Investigator Strait. The
Backstairs Biounit is defined by the 50 metre bathymetric contour and covers an area of 35,911 ha,
encompassing the waters of the Backstairs Passage and the Pages offshore islands.
MARINE BIOGEOGRAPHY
1
OCEANOGRAPHY
With the exception of Backstairs Passage and `The
Pages', this biounit has a predominantly low wave
energy regime. This is due to its northern aspect. In
the Bay of Shoals, a 10 km shoal that extends south
east from Cape Rouge, effectively blocks waves from
the gulf, creating low energy conditions inside the
Bay. In other parts of the biounit, the North East
Dudley Peninsula is a more moderate wave energy
coast, whilst `The Pages' experience moderate to high
wave energy conditions.
American River is a tidal channel that links Pelican
Lagoon to Eastern Cove. The channel is confined
by the Cambrian sediments and Holocene beach
sandflat deposits along the western shore and the
calcarenite of Picnic Point and Holocene beach
ridges and sandflats between Saphiretown and
Strawbridge Point along the eastern shore. The
lagoon itself occupies a shallow depression and is
surrounded by low calcarenite scarps, including
several low islands also formed of calcarenite. The
tidal flats are sandy mud.
3
BIOLOGY
Major Inshore Habitats
2
GEOLOGY
AND
GEOMORPHOLOGY 46
COASTAL
The Bay of Shoals is dominated by intertidal to
shallow subtidal sand deposits and a small section of
cliffs, between North Cape and Point Marsden.
Areas of low energy coastline that are subject to tidal
inundation such as the southwest section of the Bay
of Shoals are considered unusual on the island.
Within Western Cove there are extensive Holocene
beach ridges, samphire flats and sandflats. An
extensive wetland area is associated with the mouth
of Cygnet River, in the southwestern corner of
Western Cove.
−
Major intertidal habitats in the region include
low rocky cliffs and shores, sheltered bays and
estuaries (ie. intertidal mud and sandflats) and
sandy beaches.
−
Of the total inshore subtidal habitats mapped
in the Nepean Biounit (46,876 ha), seagrass
meadows comprise 23,229 ha (49.6%), sandy
bottoms comprise 21,523 ha (45.9%), and
reefs comprise 2,124 ha (4.5%). Of the total
inshore subtidal habitats mapped in the
Backstairs Biounit (1,282 ha), seagrass
meadows comprise 668 ha (52.1%), reefs
comprise 527 ha (41.1%), and sandy bottoms
comprise 87 ha (6.8%).
Eastern Cove is flanked on either side by dominant
cliffs and headlands with the southern shoreline
being predominantly sandy beaches.
North East Dudley Peninsula has very stable rocky
cliffs. Apart from minor deposits in Christmas Cove
and Hog Bay, Holocene sedimentation is restricted to
Antechamber Bay. There are two wide sandy
beaches on the peninsula and a wetland area located
at the northern end of Antechamber Bay.
Major Benthic Communities
•
−
Macroalgal
The rocky shores and reefs of the northeast
coast of Kangaroo Island (particularly east of
Kangaroo Head), generally experiences strong
tidal currents (through Backstairs Passage). In
more sheltered locations (eg. Kangaroo Head),
reef areas tend to colonised by species of
Cystophora
(C.monilifera,
C.expansa),
Caulocystis ulvifera and Sargassum (S.fallax,
S.heteromorphum).
46
From Kangaroo Island Coast Protection District Study Report
(Edwards 1987).
Page 209
KANGAROO ISLAND COAST – NEPEAN AND BACKSTAIRS BIOUNITS
While on more exposed shallow shores and
reefs (eg. Cable Bay, Snapper Head), reef
areas tend to be dominated by more robust
brown algae (ie. Scytothalia dorycarpa,
Carpoglossum confluens, Ecklonia radiata,
Seirococcus axillaris, Acrocarpia paniculata,
Carpopeltis) with species of Cystophora
(C.moniliformis, C.monilifera) and species of
Sargassum (eg. S.fallax, S.hetermorphum) as
sub-dominants, with an understorey of
Caulerpa, mixed sponges, ascidians and
bryozoans and encrusting coralline algae. At
deeper depths (ie. >12m), reef areas are
colonised by a rich faunal assemblage,
dominated by sponges (eg. Thorecta,
Dendrilla, Aplysina), soft corals (eg.
Capnella), octocorals, gorgonians (eg.
Mopsella), large bryozoans (eg. Adeona
grisea, Triphyllozoon sp. Celloporaria sp.,
Orthoscuticella ventricosa) crinoids (eg.
Cenolia trichoptera) and other echinoderms
(eg. basket stars, brittle stars, sea stars),
hydroids, and filamentous red algae. The
shallow depth of this community, and also, the
diversity and size of the sessile invertebrate
fauna, makes this type of marine habitat
unique in South Australia. The habitat is most
probably a consequence of the strong tidal
flows within Backstairs Passage.
•
−
Seagrass
Seagrass meadows are extensive in this
region, but are largely confined to Nepean Bay
(ie. Bay of Shoals, Western Cove, Eastern
Cove, Pelican Lagoon), Hog Bay and
Antechamber Bay. particularly wit and are
restricted to the sheltered embayment of
Encounter Bay.
In Western Cove
considerable seagrass has been lost and
replaced by large drifts of the red alga,
Chiracanthia arborea. In other areas, sandy
sediments are commonly colonised by species
of Zostera muelleri (from low tide level to 24m) and Posidonia australis (2-4m) in shallow
waters, with P.sinuosa, Amphibolis antarctica,
Heterozostera tasmanica, Halophila australis
generally occurring in deeper water (3-17m).
Other species also colonise sandy sediments,
particularly species of Caulerpa (eg.
C.cactoides).
Hard substrata within the
meadows (eg. isolated reefs, rocks) are
commonly colonised by large fucoids
(Scaberia agardhii, species of Sargassum),
and species of red algae, Botrycladia obovata,
and Osmundaria prolifera.
Rivers/Estuaries
−
Cygnet River estuary.
−
American River inlet.
Coastal and Offshore Islands (or Reefs)
−
North Pages, South Pages, Pages Reef
(Backstairs Passage).
−
Busby Islet, Beatrice Islet (Nepean Bay).
MARINE CONSERVATION VALUES
1
1.1
SIGNIFICANT
BIOLOGICAL
PHYSICAL FEATURES
AND
Biological
Coastal and Marine Wetlands of National
Importance
−
The Cygnet River estuary has been identified
as a wetland of national importance (see
ANCA 1996). The region includes the
saltmarshes and mudflats of the estuary mouth
(and surrounding supratidal flats), and also,
the Nepean Bay Conservation Park. The
estuary is the largest, freshwater-fed wetland
on Kangaroo Island, comprising 850 hectares
of low coastal dune, and supratidal and
intertidal
saltmarshes, saline swamps,
sandbars and mudflats, which are seasonally
inundated. The Nepean Bay Conservation
Park represents the only reserve conserving
coastal sandplain habitat on the island. The
Cygnet River estuary is an important breeding
and feeding refuge area for waterbirds
including migratory waders and is also an
important nursery area for fish. The extensive
wetland at the mouth of the Cygnet River is an
important area for wading and aquatic birds
and the area has the largest number and
highest diversity of birds on Kangaroo Island.
Page 210
KANGAROO ISLAND COAST – NEPEAN AND BACKSTAIRS BIOUNITS
Threatened species of waterbirds in the area
include the Hooded Plover, Thinornis
rubricollis (Nv, Sv), White-bellied Sea-Eagle,
Haliaeetus leucogaster (Sv), Cape Barren
Goose, Cereopsis novaehollandiae (Sv), Little
Egret, Egretta garzetta (Sv), Musk Duck,
Biziura lobata (Sv), Eastern Curlew, Numenius
madagascariensis (Sv), Fairy Tern, Sterna
nereis (Sv), Eastern Reef Egret, Egretta sacra
(Sr), Australasian Shoveler, Anas rhynchotis
(Sr) (ANCA 1996). A total of 53 species of
waterbirds have been recorded in the area: 17
are listed under international treaties. A total
of 20 species of waterbird breed in the area,
including Yellow-billed Spoonbill, Platalea
flavipes, Cape Barren Goose, Australasian
Shoveler, Musk Duck, Caspian Tern, Sterna
caspia and Fairy Tern. The seabird, Little
Penguin, Eudyptula minor, also breeds in the
area. The Cygnet River estuary has been
extensively modified north of the river by the
golf course, effluent ponds and rubbish dump.
However, south of the Cygnet River, the
estuary area is virtually inaccessible and could
be regarded as a wilderness area.47 Lloyd &
Balla (1986) considered it to be an area of
outstanding
environmental
value
and
recommended that it should be given status as
a wetland reserve.
The Nepean Bay
Conservation Park is listed on the Register of
the National Estate.
−
The American River wetland system has been
recognised as a wetland of national
importance (see ANCA 1996). The wetland
system consists of several large, permanently
shallow, seagrass-dominated lagoons (Pelican
Lagoon) which are connected to the open sea
by a narrow channel known as American
River. This area and it’s biology is particularly
significant as Kangaroo Island is almost
devoid of similar low-energy, sheltered tidal
habitats. The wetland habitats are conserved
in the American River Aquatic Reserve (1,525
ha) and the Pelican Lagoon Conservation Park
(366 ha). The lagoons contain eight islets and
the shorelines include shelly beaches, and tidal
mud and sand flats.
The area contains abundant mudflats, intertidal
and subtidal seagrass meadows (dominated by
Heterozostera tasmanica, Posidonia australis,
Halophila australis), and to a lesser extent,
subtidal algal beds (dominated by the brown
algae, Sargassum biforme and Scaberia
agardhii), which are important feeding
grounds for waterbirds and provide important
refuge, breeding and nursery habitats for many
species of fish, crustaceans and invertebrates.
Threatened species of waterbirds in the area
include Hooded Plover, Thinornis rubricollis
(Nv, Sv), Little Egret, Egretta garzetta (Sv),
Osprey, Pandion haliaetus (Sv), White-bellied
Sea-Eagle, Haliaeetus leucogaster (Sv), Cape
Barren Goose, Cereopsis novaehollandiae
(Sv), Musk Duck, Biziura lobata (Sv), Eastern
Curlew, Numenius madagascariensis (Sv),
Fairy Tern, Sterna nereis (Sv), Eastern Reef
Egret, Egretta sacra (Sr), Australasian
Shoveler, Anas rhynchotis (Sr) (ANCA 1996).
A total of 56 species of waterbirds have been
recorded in the area: 17 are listed under
international treaties. A total of 9 species of
waterbirds have been recorded breeding in the
area, including the Pied Oystercatcher,
Haematopus longirostris, Sooty Oystercatcher,
H.fuliginosus, Hooded Plover, Red-capped
Plover, Charadrius ruficapillus, and Caspian
Tern, Sterna caspia. The area is a known
nursery area for King George Whiting,
Sillaginodes punctata. Fauna in the region
include bivalve molluscs, sponges, starfishes,
anemones, holothurians, polychaetes, razor
fish (Pinna bicolor), crabs and a range of fish
species, including sting rays, eagle ray and
small sharks (Womersley & Edmonds 1979).
Commercial fish species recorded in the area
include King George Whiting, Sand Flathead,
Yellow-Eye Mullet, Aldrichetta fosteri,
Australian Salmon, Arripis truttacea, Southern
Sea Garfish, Hyporhampus melanochir,
Tommy Ruff, Arripis georgiana, and Squid,
Sepioteuthis australis.
The area is also
important for pods of local Bottle-nosed
Dolphins, Tursiops truncatus.
−
Busby and Beatrice Islets have been
recognised as wetlands of national importance
(see ANCA 1996). The low-lying islets
protrude from a large offshore sand spit,
north-west of the township of Kingscote and
are conserved in the Beatrice Islet
Conservation Park and the Busby Islet
Conservation Park. Beatrice island is an
unvegetated, mudflat/cocklebed islet that
emerges only at low tide and forms part of a
larger sand spit. It is an important area for
feeding and roosting birds.
47
Kangaroo Island Coast Protection District Study Report
(Edwards 1987).
Page 211
KANGAROO ISLAND COAST – NEPEAN AND BACKSTAIRS BIOUNITS
Busby Islet is a low vegetated island composed
of sand and shell grit and originally declared
for the conservation of wildlife habitat.
Vegetation
includes
coastal
samphire
(Sarcocornia sp.) and Atriplex. Some 28 bird
species have been recorded on the island.
Threatened species of waterbirds recorded in
the area include the White-bellied Sea-Eagle,
Haliaeetus leucogaster (Sv), Eastern Curlew,
Numenius madagascariensis (Sv), Fairy Tern,
Sterna nereis (Sv), and Little Egret, Egretta
garzetta (Sv).
−
A total of 38 species of waterbirds have been
recorded in the area: 13 are listed under
international treaties. A total of 12 species of
waterbird breed in the area, including, large
breeding rookeries of Pied Cormorants,
Phalacrocorax varius, Little Pied Cormorants,
P.melanoleucos, Black-faced Cormorants,
P.fuscescens, Australian Pelicans, Pelecanus
conspicillatus, and Australian White Ibis,
Threskiornis molucca. Both island parks are
on the Register of the National Estate.
−
Lashmar Lagoon and the Chapman River
estuary have been identified as wetlands of
national importance (see ANCA 1996). The
site consists of Lashmar Lagoon, a shallow,
freshwater (slightly brackish) lake and the
lower reaches of the Chapman River to the
river mouth, where it enters the sea at
Antechamber Bay. The site is an important
feeding and breeding refuge for waterbirds
and migratory wader species, and provides a
winter refuge for the Hooded Plover,
Thinornis rubricollis (Nv, Sv). Threatened
species of waterbirds recorded in the area
include the Hooded Plover, Little Egret,
Egretta garzetta (Sv), Freckled Duck,
Stictonetta naevosa (Sv), Musk Duck, Biziura
lobata (Sv), Lewin’s Rail, Rallus pectoralis
(Sv), Australasian Shoveler, Anas rhynchotis
(Sr), Baillon’s Crake, Porzana pusilla (Sr) and
Spotless Crake, P.tabuensis. A total of 50
species of waterbird have been recorded in the
area: 9 are listed under treaties. A total of 15
species of waterbird breed in the area,
including the White-faced Heron, Egretta
novaehollandiae, Little Pied Cormorant,
P.melanoleucos, Little Black Cormorant,
P.sulcirostris, Australasian Shoveler, Musk
Duck, Black Swan, Cygnus atratus, Buffbanded Rail, Gallirallus philippensis, and both
species of crakes. Fish recorded in the region
include the Common Galaxias, Galaxias
maculatus (Lloyd & Balla 1986).
Offshore Islands of Recognised Conservation
Significance
−
The Pages Conservation Park is home to the
largest breeding colonies of the rare Australian
Sea Lion in South Australia (and the world).
Breeding colonies occur on North Pages
Island (310 pups, estimated population 1,491)
and South Pages Island (260 pups, estimated
population 1,250) (Gales et al. 1994).
Together, these comprise a major proportion
of the Australian (and world) population
(estimated at 12,400 individuals) (Gales et al.
1994). The total population of sea lions on the
islands has increased in recent years, from a
total of 422 recorded in 1982 (Robinson &
Dennis 1988) to 1,012 recorded in 1990
(Gales 1990). In the 1990 census, a total of
595 and 417 sea lions (including 280 and 242
pups) were recorded on North and South Page,
respectively (Gales 1990). A further 140 sea
lions were recorded on SW Pages Reef,
however this is most likely a haul out site
(Gales 1990). New Zealand Fur Seals have
also been recorded on North Page
(Shaughnessy 1990). However it is not a
known breeding site for this species. These
islands are also an important breeding area for
seabirds, as recognised by their declaration as
part of a Bird Protection District under the
Birds Protection Act in 1900.
Other Areas of Recognised Conservation
Significance
−
The Backstairs Passage region is unparalleled
in it’s diversity of marine invertebrate
assemblages and is one of the richest areas for
sessile invertebrate fauna in South Australia
(Dr Scoresby Shepherd, SARDI, pers.comm.).
Strong current flows in the narrow Passage
provide optimal conditions for filter-feeding
organisms and many organisms, particularly
sponges and bryozoans, reach very large
proportions and also, importantly, outcompete
plant communities in colonising shallow reefal
areas in high current regions. The deep water
(ie. 75 m) sessile invertebrate fauna of the
Passage is of national importance with regard
to the diversity of brachiopods (Dr Scoresby
Shepherd, SARDI, pers.comm.), and possibly,
global importance if records of stalked
crinoids by the SA Museum (ie. Dr J Mitchell)
are confirmed.
Page 212
KANGAROO ISLAND COAST – NEPEAN AND BACKSTAIRS BIOUNITS
−
The Snapper Point region (including Cable
Hut Bay) is of particular significance within
Backstairs Passage. Reef communities extend
from the shoreline out to 500-700 from the
rocky headlands and form habitat for a
diverse, shallow water, animal-dominated
community (ie. 15 metres and deeper) which
is usually found in much deeper waters (50-70
metres). Within the Passage, this community
is found in a rocky channel at 75m. This is the
first shallow water record of this rich, deep
water sessile marine invertebrate community
in South Australia, and is also the only
recorded site in South Australia where this
community type is accessible on SCUBA.
The community is characterised by very large
filter-feeding organisms, particularly very
large sponge, bryozoans and crinoid
assemblages. The region which contains these
assemblages appears to be restricted to the
southern part of the Backstairs Passage (ie. the
Kangaroo Island coast). The shallow water,
sponge-bryozoan-crinoid community is highly
localised within the southern-western part of
the Passage (ie. Snapper Point region).
−
Penneshaw has breeding colonies of Little
Penguins.
−
Nepean Bay Conservation Park. This coastal
park represents the only reserved area of
coastal sandplain on Kangaroo Island. It is a
well vegetated area with low coastal dunes.
Some 80 species of birds, 8 species of reptiles
and amphibians, and 4 mammal species have
been recorded in the park. Tidal flats occur
outside the park boundary. The park is on the
Register of the National Estate.
−
Adjacent to the American River Aquatic
Reserve is the Pelican Lagoon Conservation
Park, comprising 55 hectares of low scrubland
and low open scrubland/grassland. Some 115
species of birds, 16 species of reptiles and 8
species of native mammals have been
recorded in the park.
The park offers
attractive views of Pelican Lagoon and
American River. The Pelican Lagoon
Conservation Park is on the Register of the
National Estate.
−
1.2
−
Between Ballast Head and the American River
township, dense coastal vegetation includes
Allocasuarina verticillata which is a major
feeding and breeding habitat for the Glossy
Black Cockatoo, Calyptorhynchus lathami (an
endangered species at the State level) and also
provides a major component of the habitat for
the Beautiful Firetail, Emblema bella (a rare
species at the State level).
Physical
The Bay of Shoals and Nepean Bay differ
significantly from each other. Bay of Shoals,
being a more confined bay with lower wave
energy, has no depositional features apart
from the sand/cobble shoals at the entrance.
The Nepean Bay, however, has sediments
deposited into the bay from the Cygnet River
and slightly higher wave energy, and hence
shows depositional features such as beach
ridges.
The two bays are, therefore,
considered different from each other, with Bay
of
Shoals
being
geomorphologically
representative of a low energy, nondepositional bay, and Nepean Bay being
geomorphologically representative of a
slightly higher energy, depositional bay (D.
Fotheringham pers. comm.).
Geological Monuments
•
−
Kingscote foreshore:
Late Eocene bryozoan limestone exposed in
coastal cliffs around the foreshore. Raised
beach deposit of basalt pebbles at Rolls Point.
A 700 m section of coastal cliffs to the southwest of Kingscote with teaching, recreation
and aesthetic value.
•
−
Old Government Quarry, Kingscote:
basalt of probable Jurassic age, typical of the
Kangaroo Island occurrences, but not found
on the mainland. Overlies Permian glacigene
and fluvial sediments. The Rock from the
quarry was used in Adelaide roads in 18401841. Contained within a 900 metre section
of coastal cliffs with historic and scientific
value.
•
−
The Big Gully:
Early Cambrian fossiliferous strata including
White Point Conglomerate, Emu Bay shale
and Boxing Bay formation. Includes type
section of the last. Site comprises of 2.5 km
of coastline with teaching, research and
scientific value.
Page 213
KANGAROO ISLAND COAST – NEPEAN AND BACKSTAIRS BIOUNITS
•
−
Alex Lookout to Snapper Point:
sequence of Late Precambrian and Early
Cambrian metasediments. The only exposures
of certain Precambrian rock on Kangaroo
Island. 5 km of coastline with teaching and
scientific value.
•
−
Christmas Cove, Penneshaw:
Permian glacegene sediments and erratics of
glaciates surfaces of Early Cambrian
sediments including polymictic conglomerate
with teaching and aesthetic value.
2
2.1
OTHER VALUES
Commercial Fisheries
Fishing is an important industry for all of Kangaroo
Island, for both commercial and recreational fishers.
Major single species fisheries include the Southern
Rock Lobster, Abalone and Western King Prawn.
Kingscote and Penneshaw are major ports of landing
for both Southern Rock Lobster and marine scalefish.
Kingscote has 14 of the 24 Southern Rock Lobster
boats operating from this port. American River has
only a few boats using this area as their port of
landing. Many of the mainland license holders also
fish at Kangaroo Island.
Western King Prawn
This biounit is located within the waters of the Gulf
St Vincent prawn fishery, which comprises 10
license holders (ie. boats). All vessels fish within the
waters of the Gulf St Vincent and Investigator Strait
biounits (ie. Sturt, Investigator, Orontes, Clinton,
Yankalilla, Nepean, Encounter, St Vincent). In
1995/96 and 1996/97 a total of 258,459 and 210,581
kg was caught for this fishery, with a total effort of
2,996 and 3,235 hours, respectively (or 11.38% and
10.41% of the total catch for Western King Prawn
in South Australian waters).
Southern Rock Lobster
In 1995/96 and 1996/97 a total of 4 and 3 licensed
operators fished in the Nepean Biounit (ie. Fishing
Zone 42). In addition, lobster fishing is also
present in the waters of north western Kangaroo
Island and Backstairs Passage (and also, the
southern Fleurieu) (ie. Fishing Zone 44).
In 1995/96 and 1996/97 a total of 8 and 6 licensed
operators fished in this region (ie. Fishing Zone
44), catching approximately 7,036 and 5,390 kg of
lobsters, respectively (or 0.14% and 0.11% of the
total catch for Southern Rock Lobster in South
Australian waters).
Abalone
There is limited Greenlip and Blacklip Abalone
commercially harvested within the western section
of this biounit, (ie. MapCode 32A-C, Nepean Bay,
Hog Point to Cape Cassini region). No Greenlip
was harvested in this region in 1995/96.
Greater quantities of Blacklip Abalone are
harvested in the eastern section of this biounit, (ie.
MapCode 31A-C, Antechamber Bay to Cape Hart
and False Cape, Backstairs Passage region), but
due to confidentiality constraints these figures are
not available.
Marine Scalefish Fisheries
During 1995/96 and 1996/97, 33 and 32
commercial licence holders (made up of Marine
Scalefish and Restricted Marine Scalefish licence
categories) caught commercial marine scalefish
species in the Nepean Biounit region (ie. Fishing
Zone 42), respectively. License holders expended
approximately 2,030 and 2,139 boat days effort
fishing these waters during 1995/96 and 1996/97,
respectively. The marine scalefish catch for this
region (ie. Fishing Zone 42) represented 84,372 kg
in 1995/96 and 221,191 kg in 1996/97(or 0.81%
and 2.18% of the total catch for the marine
scalefish fishery in South Australian waters).
Hand line fishing for King George Whiting occurs
around American River, Nepean Bay (including both
Western and Eastern Coves) and the Bay of Shoals.
Some netting for Garfish and King George Whiting
occurs in these areas as well. Dab netting occurs in
Western and Eastern Coves for Garfish and a Sand
Crab fisher also traps here.
Although license holders are not restricted to fishing
in this biounit, the following licenses are registered in
this area:
−
Kingscote: 15 northern zone Rock Lobster, 27
unrestricted marine scalefish, 3 restricted
marine
scalefish, 1 Abalone.
−
Penneshaw: 4 unrestricted marine scalefish.
−
American River: 1 restricted marine scalefish,
1 Rock Lobster.
Page 214
KANGAROO ISLAND COAST – NEPEAN AND BACKSTAIRS BIOUNITS
2.2
Aquaculture
Pacific Oyster rack farming and Blue Mussel
longline farming are the major mariculture industries
operating in this coastal biounit. At present, there
are 6 approved oyster leases, including, 1 lease on the
northern side of the Bay of Shoals; 1 lease in the
Cygnet River (towards the mouth end); and 2 leases
in Western Cove, near the Red Banks (ie. eastern side
of Nepean Bay Conservation Park); and 2 leases
adjacent to the Cygnet River (in land based ponds).
In addition, there are another 11 pending oyster lease
applications in this region, including, a further 7
leases in Western Cove (south of the Cygnet River);
2 more leases on the northern side of the Bay of
Shoals; 1 lease near Ballast Head; and 1 lease in the
Cygnet River. Oyster farming has been trialed in
Bay of Shoals on a number of leases and has not
proven viable (Gilliland 1996).
This region has been identified as a major area for
existing and future aquaculture development. The
Kangaroo Island Aquaculture Management Plan
(Gilliland 1996) proposes the following aquaculture
development in the region:
−
2.3
−
−
−
Bay of Shoals Zone (3,840 ha of waters of
Bay of Shoals and Spit, including waters
adjacent Busby Islet Conservation Park) –
zoned to trial aquaculture. A total of 30 ha of
R&D licenses will be considered in zone,
excluding finfish culture, and within 1km of
HWM on Busby Inlet, within 500m of `Fannie
M’ shipwreck.
Eastern Cove Zone (2 450 ha of waters in
northern Eastern Cove, from Point Morrison
to Ballast Head, east to Kangaroo Head) –
zoned to encourage sustainable shellfish
longline culture. Licenses will be considered
for a total of 200ha of shellfish longline
culture in this zone.
Western Cove Aquaculture Zone (375 ha of
coastal waters east of Nepean Bay
Conservation Park) – zoned to encourage
sustainable intertidal oyster culture. Licenses
will be considered for a total of 70ha of
intertidal oyster culture in this zone.
American River Aquaculture Zone (65 ha of
intertidal waters between Ballast Head and
American River) – zoned to encourage
sustainable intertidal oyster culture. R&D
licenses will be considered for a total of 30ha
of intertidal oyster culture in this zone.
Recreation and Tourism
Fishing
−
Kingscote: jetty and boat fishing. Major
species: King George Whiting, Black Bream,
Yelloweye Mullet, Australian Salmon,
Snapper, Snook, Garfish, Tommy Rough,
Trevally, Toothbrush Leatherjacket and
Calamari.
−
American River: boat fishing. Major species:
King George Whiting, Sand Flathead,
Yelloweye Mullet, Australian Salmon,
Garfish, Tommy Rough and Calamari.
−
Penneshaw: boat and jetty fishing. Major
species: King George Whiting, Sand Flathead,
Yelloweye Mullet, Australian Salmon, Snook,
Sweep, Garfish, Tommy Rough, Calamari,
Trevally and Toothbrush Leatherjacket.
−
Pennington Bay: boat fishing. Major species:
Sand Flathead, Yelloweye Mullet, Australian
Salmon, Sweep, Tommy Rough, Trevally,
Toothbrush
Leatherjacket
and
Silver
Drummer.
−
There is an artificial reef located off Kingscote
(consisting of 450 rubber tyre modules).
Nepean Bay Policy Area
−
Nepean Bay Aquaculture Zone (26,880 ha of
offshore waters of Nepean Bay) – zoned to
provide for future interest in aquaculture.
Licenses will be considered for a total of
250ha of aquaculture in this zone, comprising
a total of 200ha of longline shellfish culture, in
this zone.
Tourism
−
Bay of Shoals: boating, fishing, historic area
(Reeves Point)
−
Western Cove and Kingscote: boating, jetty
fishing, historic area, scenic area.
−
Eastern cove: boating, jetty fishing, camping,
historic area, scenic area.
−
Penneshaw: penguin `parades', historic area,
camping, jetty fishing, boating.
−
Penneshaw to Cape Willoughby: scenic area,
historic area, camping, fishing, boating.
Page 215
KANGAROO ISLAND COAST – NEPEAN AND BACKSTAIRS BIOUNITS
−
2.4
−
−
2.5
SCUBA diving: there are many popular diving
locations in this region, particularly near
Kangaroo Head and Penneshaw. Several of
these are utilised by local dive operators for
training (eg. Adventureland Diving).
The
Penneshaw jetty is a very popular local diving
spot for training novice divers, night diving
and underwater photography. Strong tidal
flows in the area have produced a wide range
of marine life on the pylons, particularly very
large gorgonian or fan corals.
Scientific Research and Education
Pelican Lagoon Wildlife Research Centre is
situated on the shores of Pelican Lagoon
(American River inlet), and provides research
facilities and accommodation for a wide range
of national and international scientists. The
field centre is globally recognised for the
range of research facilities and activities
conducted, and also, the diversity of natural
habitats and biota available for scientific
research. Studies encompass a wide range of
ecological and physiological projects on the
terrestrial fauna and flora (particularly
mammals and reptiles), to more recently,
studies on the marine habitats of Pelican
Lagoon, as part of a `CoastCare’ community
grant. Pelican Lagoon has been the site of
marine research investigations by the
University of Adelaide (and more recently, the
SA Herbarium), since the 1940s.
American River inlet, and the coastal areas
surrounding Kingscote and Penneshaw, have
been regular research sites since the early
1940's for marine algal collections and
intertidal studies (see Womersley 1950, 1956,
Womersley & Edmonds 1958, 1979).
Adjacent Land Use
National and Conservation Parks
−
−
−
−
Nepean Bay Conservation Park (30 ha)
(SANPSW 1987).
Pelican Lagoon Conservation Park (365 ha)
(SANPWS 1987).
Dudley Conservation Park (1,122 ha)
(SANPWS 1987).
Lashmar Conservation Park, Antechamber
Bay (188 ha).
Offshore Island Parks:
−
The Pages Conservation Park (15 ha).
−
Busby Islet Conservation Park (10 ha).
−
Beatrice Islet Conservation Park (10 ha).
Agriculture/Industry
The majority of land surrounding the eastern portion
of Eastern Cove is used for rural purposes, whereas
the southern portion contains a significant belt of
vegetation. A major shipping jetty is located at
Ballast Head in connection with the gypsum mining
industry which ceased operation in 1992. On the
Kingscote foreshore there is an old basalt quarry and
wharf.
Major sources of point-source pollution in this
biounit include: a major storm water outfall near the
Kingscote Yacht Club building; a septic tank
overflow outlets along the foreshore north of Pelican
Point; septic overflow pipes at American River from
the hotels and motels along the coast. 48
Urban Centres
−
Kingscote (population 1,450). Kingscote also
has a permanent coastal mooring facility for
recreational craft.
−
Penneshaw (population 300).
−
American River (population 250). American
River also has a permanent coastal mooring
facility for 81 recreational craft.
Whilst Penneshaw and American River are relatively
small urban centres, they are important tourist
destinations and hence experience considerably
higher populations during the warmer months of the
year.
2.6
Features
Significant Cultural or Historical
Aboriginal
−
Reeves Point contains land that has been
proclaimed an Historic Reserve under the
Aboriginal and Historic Relics Act 1975.
48
From Kangaroo Island Coast Protection District Study Report
(Edwards 1987).
Page 216
KANGAROO ISLAND COAST – NEPEAN AND BACKSTAIRS BIOUNITS
European
−
−
−
The first band of pioneers landed from the
Duke of York at Kingscote on 27th July 1836.
Reeves Point, the actual site of the first
landing and South Australia's first official
settlement, is of great historical significance
and archaeological value. Reeves Point is
registered on the State Heritage Register,
Register of the National Estate and is
classified on the National Trust.
American River is one of the oldest known
areas of South Australia. It was originally
called Pelican Lagoon by Matthew Flinders in
1802 because of the large number of pelicans
found there. There are numerous heritage
items within the township and on the coast.
These include, the Anchor Memorial on the
foreshore, a cairn on the site where the 40 ton
schooner, `Independence', was constructed
from native pine in 1803 by Americans, the
Muston jetty ruins on the western shoreline of
Pelican Lagoon and the Matthew Flinders
Cairn situated in the south western corner of
Pelican Lagoon.
There are also several
heritage sites within the existing Pelican
Lagoon Conservation Park. The lagoon itself
is considered to be of State heritage
significance due to its variety of historical
associations relating to initial contact and
primary industries and is on the Register of the
National Estate.
Kangaroo Head is where Flinders landed and
from which he saw and named Mount Lofty
on the mainland.
Christmas Cove was
chartered and named by Flinders in 1802. As
the first documented landfall on the island by
Flinders, Christmas Cove is a site of high
memorial value and is one of the historically
significant natural coastal features in the State.
The wreck site lies in 2-3 metres of water in a
slight sand depression but only a small amount
of the surviving hull structure is visible above
the seabed.
−
`Fannie M’, lost in 1885 (off the Bay of
Shoals),
and
is
protected
under
Commonwealth legislation.
3
CURRENT CONSERVATION STATUS
OF THE NEPEAN AND BACKSTAIRS
BIOUNIT
−
Marine Reserves
American River Aquatic Reserve (1,525 ha)
−
Marine Parks
None
−
Netting Closures
Kingscote Spit (waters enclosed by lines from
Cape Rouge to south to the The Bluff then to
Kingscote jetty, and then around Kingscote
Spit to Point Marsden).
−
Bay of Shoals (all waters west of the line from
Cape Rouge and The Bluff are closed from 1
January to 31 March every year).
−
American River – Eastern Cove (all waters
south a line from American Beach to western
shore of Eastern Cove, approximately one
nautical mile south west of Ballast Head jetty).
−
Kangaroo Island Rivers (Chapmans, Harriet,
Eleanor, Western and Middle Rivers and all
waters within a 50 metre radius of the mouths
of those rivers).
4
AREAS OF HIGH CONSERVATION
VALUE IN THE NEPEAN AND
BACKSTAIRS BIOUNITS
49
−
The Penneshaw jetty is also a site of historical
significance.
Shipwrecks
−
49
`Robert Burns' was built as a fore and aft
schooner at Long Bay, Hobart, Tasmania in
1857. It went ashore on the sand spit in
Nepean Bay in 1908 when the master
confused the leading lights on the shore for
those of the Ozone Hotel.
From Kangaroo Island Coast Protection District Study Report
(Edwards 1987).
Ironstone Point – Antechamber Bay
−
Prime IUCN Conservation Values: rare and
threatened
species/habitats,
biodiversity
(IUCN Category IA). IUCN Identification
Criteria: naturalness (not subjected to humaninduced change), biogeographic (high tidal
flow environment, rare shallow-water sponge
communities, geological monument-Alex
Lookout to Snapper Point), ecological
(representative habitats, soft bottom spongeascidian communities, seagrass meadowsPage 217
KANGAROO ISLAND COAST – NEPEAN AND BACKSTAIRS BIOUNITS
Antechamber Bay, high diversity of marine
flora and fauna-brachyiopod fauna, rare and
threatened species-Hooded Plover, Little
Egret, Baillons Crake, Spotless Crake,
breeding colonies of White-faced Heron, Little
Pied Cormorant, Little Black Cormorant,
crakes), economic (fisheries-Western King
Prawn, Blacklip Abalone), social (recreation,
tourism, SCUBA diving), national (Wetland of
National Importance - Lashmar Lagoon and
Chapman
River
estuary),
practicality
(insulation,
accessibility,
compatibilityadjacent to Lashmar Lagoon).
American River
−
Prime IUCN Conservation Values: rare and
endangered
species/habitats,
research,
biodiversity (IUCN Category IA).
IUCN
Identification Criteria: naturalness (not
subjected
to
human-induced
change),
biogeographic
(representative
habitats),
ecological (ecological integrity, extensive
seagrass meadows, nursery, feeding, and
breeding for fish and crustaceans-eg. King
George Whiting, rare and threatened species–
Sygnathids, waterbirds-Hooded Plover, Little
Egret, Osprey, White-bellied Sea Eagle, Cape
Barren Goose, Eastern Curlew, Fairy Tern,
Eastern Reef Egret, Australasian Shoveler,
breeding colonies of Pied Oystercatcher,
Sooty Oystercatcher, Hooded Plover, Redcapped Plover, Caspian Tern), economic
(fisheries-King George Whiting, Southern Sea
Garfish),
social
(recreation,
tourism,
European heritage-American River, Pelican
Lagoon), scientific (Pelican Lagoon Research
Centre), national (Wetlands of National
Importance and Register of the National
Estate-American River Aquatic Reserve,
Pelican
Lagoon
Conservation
Park),
practicality
(accessibility,
insulation,
compatibility-adjacent to Pelican Lagoon
Conservation Park, American River Aquatic
Reserve).
Lions), national (Register of the National
Estate - Pages Conservation Park),
practicality (insulation, compatibility-adjacent
to Pages Conservation Park).
Bay of Shoals - Western Cove
−
Prime
IUCN
Conservation
Values:
biodiversity,
rare
and
threatened
species/habitats,
social
values
(IUCN
Category IA). IUCN Identification Criteria:
naturalness (not subject to human induced
change),
biogeographic
(representative
habitats), ecological (ecological integrity,
extensive seagrass meadows, key nursery,
feeding and breeding area for fish and
crustaceans, significant breeding area for
seabirds and waderbirds-Pied Cormorants,
Little
Pied
Cormorants,
Black-faced
Cormorants, Australian Pelicans, Australian
White Ibis, Yellow-billed Spoonbill, Cape
Barren Goose, Australasian Shoveler,
Caspian Tern, Fairy Tern, Little Penguin, rare
and threatened fauna-Hooded Plover, Whitebellied Sea Eagle, Cape Barren Goose, Little
Egret, Eastern Curlew, Fairy Tern, Eastern
Reef Egret), economic (marine scalefish
fisheries-King George Whiting, Southern Sea
Garfish),
social
(recreation,
tourism,
shipwrecks-`Robert Burns’, `Fannie M’),
national (Wetlands of National ImportanceCygnet River estuary, American River wetland
system, Busby and Beatrice Islets, Register of
the National Estate–Nepean Bay Conservation
Park, Busby and Beatrice Islets Conservation
Parks),
practicality
(accessibility,
compatibility-adjacent to Nepean Bay
Conservation Park, Busby Islet and Beatrice
Islet Conservation Parks).
Pages Islands
−
Prime IUCN Conservation Values: rare and
threatened
species/habitats,
research,
biodiversity (IUCN Category IA).
IUCN
Identification Criteria: naturalness (not
subject to human induced change),
biogeographic
(representative
habitats),
ecological (high biodiversity, reef habitats,
rare and threatened fauna – largest breeding
colony of Australian Sea Lions in the world,
haul out site for New Zealand Fur Seals,
breeding colonies of Little Penguin, Crested
Tern), economic (fisheries-Southern Rock
Lobster, Abalone), social (recreation),
scientific (research/monitoring-Australian Sea
Page 218
KANGAROO ISLAND COAST – GANTHEAUME BIOUNIT
XXV
MARINE BIOGEOGRAPHY AND CONSERVATION VALUES OF THE
GANTHEAUME BIOUNIT
From Cape Willoughby to Cape Borda, this biounit covers an area of 167,363 ha and encompasses 51% of the
Kangaroo Island shoreline (232 km). It faces south into the Southern Ocean.
MARINE BIOGEOGRAPHY
1
OCEANOGRAPHY
This section of Kangaroo Island by virtue of its
southern and westerly aspect, contains all of the high
wave energy areas of the island. Most of this coastal
region is fully exposed to the Southern Ocean,
experiencing strong prevailing southerly and southwesterly winds which result in a heavy surge or swell
environment, with waves up to 2m high. Lower
energy areas occur only in the east-facing D'Estrees
Bay.
2
GEOLOGY
AND
GEOMORPHOLOGY 50
COASTAL
Calcarenite blankets all of the southern and western
fringe of the island. The coastline is characterised by
bedrock headlands, extensive bedrock and/or
calcarenite cliffs and shore platforms, with a few
Holocene beach deposits. All beaches and cliffs are
capped and backed by dunes. Lower energy
Quaternary beach-foredune ridges only occur in
D'Estrees Bay.
Around Cape Willoughby, granite headlands reach
up to 100 m high and slope moderately toward the
coast. At Cape Hart Conservation Park, the granites
are replaced by Middleton sandstone which forms 40
to 80 metre high cliffs fronted by 40 to 100 m wide
supratidal horizontal shore platforms. There is also a
shingle beach in the Cape Hart Conservation Park.
Stable dune calcarenite scarped and fronted by
intertidal shore platforms dominates the coastline
from False Cape to Cape Tinline. Most of the cliffs
are capped by stable Holocene cliff top dunes. Wave
energy is highest in the east area producing high
energy intermediate beaches and surf zones often
containing reefs. The energy gradually declines to
the west, producing current generated sand waves in
D'Estrees Bay.
Pleistocene dune transgressions that have lithified
into dune-calcarenite cliffs and shore platforms, and
Holocene dune transgressions that appear in a few
high energy beaches dominate the coast from Cape
Linois to Bales Beach.
Vivonne Bay and Bales Beach represent one of the
few remnants along the south coast of the once
extensive beach-dune systems. The Eleanor and
Harriet Rivers reach the coast at Vivonne Bay, where
they are often dammed by a berm resulting from the
infrequent flow of the rivers and the high waves at
the coast. Brackish lagoons lie in lee of the berm.
Approximately 8 km of eroding dune calcarenite
cliffs and shore platforms separate Vivonne Bay and
Seal Beach.
The Cape Kersaint section of coast is dominated by
Pleistocene calcarenite cliffs 20 to 70 m high and
extending inland between 1 and 5 km. Wide sloping
supratidal bedrock shore platforms occur in front of
the cliffs. The Stun'sail Boom River empties out at
the coast on the eastern side past Kelly Hills
Conservation Park. Its mouth is usually blocked by a
150 m long beach, forming a brackish lagoon.
Hanson Bay is similar to the other south coast
sections of substantial Holocene dune transgression,
with cliffs ranging from 30 to 60 m and fronted by
wide intertidal shore platforms.
Cape Younghusband to Cape du Couedic is mainly
granite headlands, which have been blanketed by
multiple episodes of Pleistocene dune transgression.
The dunes are highest in the west where they reach
altitudes of 150 m, decreasing in elevation and
thickness eastward. At the coast the highest dune
calcarenite cliffs and escarpments are between Cape
du Couedic and Kirkpatrick Point where they reach
elevations of 130 m.
The 34 km section of coast from Cape Bedout to
Cape Borda is cliffed throughout (except for four
river mouths), with cliffs averaging 70 m in height
and generally increasing in height northward from 30
to 50 m to 100 to 130 m by Cape Borda. The four
rivers empty out at the coast at beaches that are
susceptible to high wave attack and overwashing
aeolian processes.
50
From Kangaroo Island Coast Protection District Study Report
(Edwards 1987).
Page 219
KANGAROO ISLAND COAST – GANTHEAUME BIOUNIT
3
BIOLOGY
Major Inshore Habitats
−
Major intertidal habitats in the region include
mostly exposed rocky cliffs, bays and sandy
beaches.
−
Of the total inshore subtidal habitats mapped
in the biounit (52,641 ha), reefs comprise
31,857 ha (60.5%), sandy bottoms comprise
19,521 ha (37.1%), and seagrass meadows
comprise 1,263 ha (2.4%).
•
Seagrasses
−
Seagrass meadows are sparse in this region
and are restricted to the shallow, sheltered
regions of D’Estrees Bay (Pennington Bay)
and Vivonne Bay. Sandy sediments are
commonly colonised by species of Posidonia
(P.sinuosa, P.angustifolia), and Amphibolis
antarctica.
In Pennington Bay and Point
Tinline, Posidonia robertsoniae occurs. On
exposed coasts (eg. Seal Bay, Vivonne Bay,
Cape Hart, Cape Gantheaume, Cape Kersaint,
Hanson Bay, West Bay), species of Caulerpa
(C.longifolia, C.brownii, C.flexilis, C.obscura,
C.scapelliformis, C.simpliuscula) tend to
dominate the sand-covered reefs and sandy
areas.
Major Benthic Communities
•
−
Macroalgal
The rocky shores and reefs of the southern and
western coast of Kangaroo Island, generally
experience strong swells and high wave
exposure. Shallow, sand covered, exposed
reefs tend to dominate this region. In areas
with heavy granite boulders (eg. Cape
Kersaint, West Bay), hard substrata is
commonly dominated by large fucoid brown
algae
(ie.
Scytothalia
dorycarpa,
Carpoglossum
confluens,
Seirococcus
axillaris, Acrocarpia paniculata) with species
of Cystophora (C.moniliformis, C.retorta).
Limestone reefs tend to be dominated by
species of Caulerpa (C.longifolia, C.flexilis),
with species of Sargassum (S.fallax,
S.sonderi), Melanthalia and species of
Cystophora
(C.moniliformis,
C.retorta,
C.grevillea, C.platylobium, C.pectinata), or
large mixed red algal assemblages (ie.
Osmundaria
prolifera,
Callophyllis,
Phacelocarpus, Plocamium), Homeostrichus
sinclairii and coralline algae (eg. Haliptilon,
Metagoniolithon). Species of Caulerpa in this
region, tend to form major communities, codominating with fucoid and red algal
communities in sand-covered reefal and
boulder habitats.
Rivers and Estuaries
−
Stun'sail Boom
National Park).
−
Small estuarine wetland associated with the
mouth of the Willson river.
−
Small estuaries at Breakneck, Sand and Rocky
Rivers (Flinders Chase National Park).
−
Small estuaries at Eleanor, Harriet and South
West Rivers.
River
(Flinders
Chase
MARINE CONSERVATION VALUES
1
1.1
SIGNIFICANT
BIOLOGICAL
PHYSICAL FEATURES
AND
Biological
Coastal and Marine Wetlands of National
Importance
−
D’Estrees Bay has been identified as a
wetland of national importance (see ANCA
1996). The site, from Shag Rock to 8km
south of Point Tinline, occupies the southern
part of D’Estrees Bay and provides an
important feeding grounding for waterbirds,
particularly migratory waders.
Page 220
KANGAROO ISLAND COAST – GANTHEAUME BIOUNIT
Threatened species recorded in the area
include, the Hooded Plover, Thinornis
rubricollis (Nv, Sv), Osprey, Pandion
haliaetus (Sv), Fairy Tern, Sterna nereis (Sv),
and the Eastern Reef Egret, Egretta sacra (Sr)
(ANCA 1996). A total of 27 waterbirds have
been recorded in the area: 10 are listed under
international treaties.
A total of 6 species
have been recorded breeding in the area:
including the Osprey, Pied Oystercatcher,
Haematopus longirostris, Sooty Oystercatcher,
H.fuliginosus, Hooded Plover, Red-capped
Plover, Charadrius ruficapillus and Caspian
Tern, Sterna caspia. The southern end of the
Bay is included in the Cape Gantheaume
Conservation Park.
Cape Gantheaume
Conservation Park lies within the Gantheaume
Wilderness Protection Area proclaimed under
the Wilderness Protection Act 1992.
−
The river systems of Flinders Chase National
Park (ie. North West River, Breakneck River,
Rocky River) has been identified as a wetland
of national importance (see ANCA 1996).
The rivers combined represent an unique
ecosystem in South Australia, and are the best
examples of pristine river systems and plateau
swamps in South Australia (ANCA 1996).
The catchments of Rocky River and
Breakneck River are the only undisturbed
river catchments in South Australia.
Threatened flora in the area include, the
Kangaroo Island Daisy, Achnophora tatei (Sr)
and Port Lincoln Mallee, Eucalyptus
lansdowneana spp. lansdowneana (Sr).
Threatened species of waterbirds recorded in
the area include the Hooded Plover, Thinornis
rubricollis (Nv, Sv) White-bellied Sea-Eagle,
Haliaeetus leucogaster (Sv), Cape Barren
Goose, Cereopsis novaehollandiae (Sv), Musk
Duck, Biziura lobata (Sv), Lewin’s Rail,
Rallus pectoralis (Sv), Painted Snipe,
Rostratula benghalensis (Sv), Latham’s Snipe,
Gallinago hardwickii (Sv), Australasian
Bittern, Botaurus poiciloptilus (Sv), Baillon’s
Crake, Porzana pusilla (Sr) and Spotless
Crake, P.tabuensis (Sr). A total of 35 species
of waterbirds have been recorded in the area: 6
are listed under treaties. A total of 6 species
of waterbirds breed in the area, including the
Cape Barren Goose, Australian Wood Duck,
Chenonetta jubata, White-bellied Sea-Eagle,
Baillon’s Crake, Masked Lapwing, Vanellus
miles, and Red-capped Plover, Charadrius
ruficapillus. The Rocky River and Breakneck
River support important colonies of Platypus
(Sv) in South Australia.
The Breakneck River and Larrikin Lagoon lie
within the Ravine Des Casoars Wilderness
Protection Area proclaimed under the
Wilderness Protection Act 1992.
−
Grassdale Lagoons and the estuary of the
South West River are recognised as wetlands
of national importance (see ANCA 1996).
The site is located within the Kelly Hill
Conservation Park, and consists of 2
permanent freshwater lagoons and the down
stream portion of the South West River (down
to the river mouth at Hanson Bay). The
estuary is a winter and rough weather refuge
for the Hooded Plover, Thinornis rubricollis
(Nv, Sv) and Osprey, Pandion haliaetus (Sv).
Two species of threatened plants are recorded
in the area: the Kangaroo Island Daisy and
Schoenus discifer (Sr). Threatened species of
waterbirds recorded in the area include, the
Hooded Plover, Osprey, White-bellied SeaEagle, Haliaeetus leucogaster (Sv), Musk
Duck, Biziura lobata (Sv), Freckled Duck,
Stictonetta naevosa (Sv), Latham’s Snipe,
Gallinago hardwickii (Sv), Eastern Reef
Egret, Egretta sacra (Sr),
and the
Australasian Shoveler, Anas rhynchotis (Sr).
A total of 51 species of waterbirds have been
recorded in the area: 10 are listed under
treaties. A total of 11 species of waterbirds
are recorded breeding in the area: including,
the Little Pied Cormorant, Phalacrocorax
melanoleucos,
Australian
White
Ibis,
Theskiornis molucca, Chestnut Teal, Anas
castanea, Australian Wood Duck, Chenonetta
jubata, Musk Duck, Australian Spotted Crake,
Porzana fluminea, and Purple Swamphen,
Porphyrio porphyrio.
The Kelly Hill
Conservation Park is on the Register of the
National Estate. Most of the park is in the
Cape Bouguer Wilderness Protection Area
proclaimed under the Wilderness Protection
Act 1992.
Other Areas of Recognised Conservation
Significance
−
The southern and western coasts of Kangaroo
Island, particularly Seal Bay, comprise one of
the three major breeding areas for the rare
Australian Sea Lion (Neophoca cinerea) in
South Australia (after the Pages and
Dangerous Reef). The population of the south
coast of Kangaroo Island, particularly Seal
Bay has been estimated at 866 (ie. 180 pups)
(Gales et al. 1994).
Page 221
KANGAROO ISLAND COAST – GANTHEAUME BIOUNIT
Breeding colonies occur at Seal Bay (Pup
Cove, Western and Eastern Prohibited Area,
and the main beach), and Cape Gantheaume
(Robinson & Dennis 1988, Gales 1990). Haul
out sites occur at Cape du Couedic, North and
South Casuarina, West Bay Island and Cape
Bouger (Robinson & Dennis 1988).
−
−
−
The southern and western coasts of Kangaroo
Island comprise the second largest breeding
area for New Zealand Fur Seals
(Arctocephalus forsteri) in South Australia
(after the Neptune Isles). Major breeding sites
for fur seals occur at Cape Gantheaume (525
pups, estimated population 2573), North
Casuarina (442 pups, estimated population
2166) and Cape du Couedic (including
Admirals Arch, Ladders South, Ladders
North, Nautilus Rock, Nautilus North) (477
pups, estimated population 2337) (Robinson &
Dennis 1988, Shaughnessy et al. 1994).
Together, these colonies on the south coast
comprise an estimated 7076 individuals,
representing some of the major breeding sites
for Fur Seals in South Australia (ie. 26% of
the total estimated population of 27,616 in
South Australia) - along with the Neptune
Islands (estimated population of 16,886) and
Liguanea Island (estimated population of
2720). Fur Seals have also been recorded at
Cave Point, Cape Bouguer, Seal Beach, South
Casuarina, Weir Point, Vennachar Point,
Paisley Island and Cape Borda. However no
breeding has been recorded at these sites
(Shaughnessy 1990).
The Seal Beach Aquatic Reserve and Seal Bay
Conservation Park provides a sanctuary for the
resident Australian Sea Lion colony which
represents more than 10% of the total
population of the species. Major habitats
include sandy beach, offshore reefs, high wave
energy coastline and exposed rocky coast.
Seal Bay and Cape Gantheaume National Park
are on the Register of the National Estate.
−
Flinders Chase National Park is the largest
park on the island. The coast is characterised
by high cliffs broken by small sandy bays and
estuaries where rivers reach the sea. Native
fish found in the rivers include the Mountain
Galaxia (Galaxias olidus), Common Galaxias
(G.maculatus), and the Climbing Galaxias
(G.brevipinnis). Flinders Chase is considered
to be one of the few remaining areas of
wilderness in South Australia. This park is on
the Register of the National Estate. Most of
the park is now contained in the Ravine des
Casoars
Wilderness
Protection
Area
proclaimed under the Wilderness Protection
Act 1992.
−
The Stun'sail Boom River (Flinders Chase
National Park) was considered by Lloyd &
Balla (1986) to be an area of outstanding
environmental value and they recommended
that it should be given status as a wetland
reserve.
−
Cape Hart Conservation Park was originally
dedicated as a representative sample of coastal
vegetation and soils of the southern part of the
eastern end of Kangaroo Island. There have
been six native mammals recorded in the park.
It has impressive coastal cliffs and scenery,
and the vegetation consists of open scrub/low
shrubland/open heath and low open forest.
−
Vivonne Bay Conservation bay is an area of
outstanding scenic coastal landscape with
vegetation not found in other areas. Sixty five
species of birds have been recorded in the
park. This park is on the Register of the
National Estate.
−
Basement "highs" such as Sanders Bank and
Carter Knoll south and east of Kangaroo
Island appear to represent zones of vigorous
growth of reef flora and fauna, including
bryozoans (C.Von der Borch, pers. comm.).
Harriet River (Vivonne Bay Conservation
Park) was considered by Lloyd & Balla (1986)
to be an area of outstanding environmental
value and recommended it should be given
status as a wetland reserve.
Page 222
KANGAROO ISLAND COAST – GANTHEAUME BIOUNIT
1.2
−
−
−
Physical
The Murray Submarine Canyons are giant
submarine canyons 60 km south of southern
Kangaroo Island. Some of these huge clefts
are larger than the Grand Canyon in the
U.S.A. They wind their way from the outer
continental shelf to oceanic depths of
approximately 4,600m.
They may be
important as a valuable source of upwelling
water which contributes to the nutrients of the
food chain (Von der Borch 1979). The
sediments of the canyon walls could contain a
record of the major geological changes that
occurred during the evolution of the South
Australian continental margin.
GLORIA
sidescan sonar images reveal steep, rugged
topography that would probably contain some
unique, little known ecosystems (Von der
Borch, pers. comm.).
Along a rocky section of coast 100 metres
north of the Ravine des Casoars, the back part
of a Holocene dune containing multiple soil
horizons has been preserved at the entrance to
a sea cave. The dune provides evidence that
during part of the Holocene period the now
rocky coast was fronted by a beach/dune
system, and as such illustrates the dynamic
nature of coasts and the dramatic changes
since the Holocene period. The site is
significant for both geomorphological research
and teaching.
Cape Hart Conservation Park (see above).
Geological Monuments
•
−
West Bay:
Pleistocene
aeolianite
unconformably
overlying Early Cambrian metasediments
within Flinders Chase National Park. 300m of
coastline with teaching and aesthetic value.
•
−
Cape du Couedic:
coastal geomorphology, including Admiral
Arch - a major tourist attraction within
Flinders Chase National Park. 300m of
coastline with teaching, recreation and
aesthetic value.
•
−
Remarkable Rocks:
spectacular sculptured granite landforms at
Flinders Chase National Park. A major tourist
attraction.
•
−
Point Ellen, Vivonne Bay:
Early Cambrian migmatites and schists
overlain by Pliocene shell bed. Spectacular
convolute folding in the migmatites and cross
cutting pegmatite. 1km of coastline with
teaching, scientific and aesthetic value.
•
−
Cape Willoughby Granite Contact:
Late Cambrian granite and metasediments of
the Kanmantoo Group (Middleton Sandstone).
600m of coastline with teaching, scientific and
aesthetic value.
2
OTHER VALUES
2.1
Commercial Fisheries
Major single species fisheries in this biounit include
the Southern Rock Lobster and Abalone. The biounit
is one of the major areas for commercial harvesting
of Blacklip Abalone in South Australia.
Southern Rock Lobster
The southern coast of Kangaroo Island consists
principally of 3 fishing zones: Fishing Zone 39 (see
Cassini Biounit), Fishing Zone 48 (south western
coast) and Fishing Zone 49 (southern coast). In
1995/96 and 1996/97 a total of 37 and 35 licensed
operators fished along the south coast of Kangaroo
Island (ie. Fishing Zone 48 and 49), catching
approximately 128 941 and 118 486 kg of lobsters,
respectively (or 2.52% and 2.32% of the total catch
for Southern Rock Lobster in South Australian
waters). However, the catch is significantly greater
(almost twice) in the southern sector (ie. Fishing
Zone 49). Approximately 10 of the 24 boats based at
Kangaroo Island use Vivonne Bay as their port of
landing for Southern Rock Lobster.
Abalone
Both Blacklip Abalone and Greenlip Abalone are
presently commercially harvested within the
Gantheaume Biounit. The region, particularly near
Cape Gantheaume, represents one of the major
areas for the harvesting of Blacklip Abalone in
South Australia. In 1994/95 and 1995/96 a total of
8,046 and 11,943 kg of Greenlip was harvested
within this region (ie. MapCode 26A-B, 27A-B,
28A-B, 29A-D, 30A-C, West Bay to Charlies
Gulch, Destres Bay region), and represented 5.6%
and 8.4% of the total Greenlip Central Zone catch
Page 223
KANGAROO ISLAND COAST – GANTHEAUME BIOUNIT
(or 2.14% and 3.19% of the total catch for
Greenlip in South Australian waters). In
1994/95 and 1995/96 a total of 33,168 and
32058 kg of Blacklip was harvested within
this region, and represented 83.8% and 76.0%
of the total Blacklip Central Zone catch (or
6.71% and 6.92% of the total catch for
Blacklip in South Australian waters).
Hanson Bay Policy Area
−
Inner Hanson Bay Zone (3,000 ha of coastal
waters, within 1km of the coast, from
Sanderson Bay to Cape Kersaint, excluding
waters adjacent to Cape Bouger Wilderness
Area) – zoned for limited coastal aquaculture
development. Licenses will be considered for
a total of 60ha of aquaculture development in
this zone, excluding intertidal oyster culture.
−
Outer Hanson Bay Zone (3,000 ha of offshore
waters from Sanderson Bay to Cape Kersaint)
– zoned for R&D open water aquaculture
development. Licenses will be considered for
a total of 12ha of R&D aquaculture
development in this zone.
Marine Scalefish Fisheries
The southern coast of Kangaroo Island consists
principally of 3 fishing zones: Fishing Zone 39 (see
Cassini Biounit), Fishing Zone 48 (south western
coast) and Fishing Zone 49 (southern coast).
During 1995/96 and 1996/97, a total of 42 and 44
commercial licence holders (made up of Marine
Scalefish and Restricted Marine Scalefish licence
categories) caught commercial marine scalefish
species along the south coast of Kangaroo Island
(ie. Fishing Zones 48 and 49), respectively.
License holders expended approximately 1620 and
1230 boat days effort fishing these waters during
1995/96 and 1996/97, respectively. The marine
scalefish catch for this region (ie. Fishing Zones 48
and 49) represented a total of 269,658 kg in
1995/96 and 168,256 kg in 1996/97(or 2.59% and
1.66% of the total catch for the marine scalefish
fishery in South Australian waters).
Marine scalefish fisheries are not large in this area,
and this is mainly due to the rugged nature of the
southern coast. There is one Salmon purse seine
netter in D'Estrees Bay who nets approximately 400
tonnes/year, although this includes figures from the
Eyre Peninsula coast.
Deep Sea fishing for Trevalla occurs on the edge of
the continental shelf. Commonwealth licence holders
in this area use dropline and also shark netting.
2.2
Vivonne Bay Policy Area
−
Inner Vivonne Bay Zone (840 ha of coastal
waters within bay, excluding waters adjacent
to Vivonne Bay Conservation Park, Seal Bay
Conservation Park and Cape Gantheaume
Wilderness Protection Area) – zoned for
limited coastal aquaculture. Licenses will be
considered for a total of 40ha of aquaculture
development in this zone, excluding intertidal
oyster culture.
−
Licenses will not be considered for remaining
waters of Vivonne Bay.
Cape Gantheaume Policy Area
−
Inner Cape Gantheaume Zone (5,120 ha of
coastal waters, within 1 km of coast, adjacent
Cape Gantheaume Wilderness Protection Area
to Destres Bay, Point Reynolds, excluding all
waters south of southern Destres Bay) – zoned
for limited coastal aquaculture development.
Licenses will be considered for a total of 40ha
of aquaculture development in this zone,
excluding intertidal intertidal oyster culture.
−
Outer Cape Gantheaume Zone (22,280 ha of
offshore waters, adjacent Cape Gantheaume
Wilderness Protection Area to Destres Bay,
Point Reynolds, excluding all waters south of
southern Destres Bay) – zoned for R&D open
water aquaculture development. Licenses will
be considered for a total of 12ha of R&D
aquaculture development in this zone.
Aquaculture
None.
The Kangaroo Island Aquaculture
Management Plan (Gilliland 1996) proposes limited
aquaculture development in this region:
Flinders Chase Policy Area
−
Flinders Chase Policy Area (37,940 ha of
waters adjacent to the Ravine Des Casoars
Wilderness Protection Area and Flinders
Chase National Park) – zoned to protect
conservation areas. Licenses will not be
considered for aquaculture development in
this zone.
Page 224
KANGAROO ISLAND COAST – GANTHEAUME BIOUNIT
Cape Hart Policy Area
−
−
−
Inner Cape Hart Zone (4,660 ha of coastal
waters, within 1 km of coast, from Point
Tinline to Cape Willoughby, excluding
Pennington Bay, Mouth Flat Beach and waters
adjacent to Cape Hart Conservation Park) –
zoned for limited coastal aquaculture
development. Licenses will be considered for
a total of 60ha of aquaculture development in
this zone, excluding intertidal intertidal oyster
culture.
Outer Cape Hart Zone (22,280 ha of offshore
waters, from Point Tinline to Cape
Willoughby) – zoned for R&D open water
aquaculture development. Licenses will be
considered for a total of 12ha of R&D
aquaculture development in this zone.
Cape Hart Aquaculture Zone (1,000 ha of
offshore waters, west of Pennington Bay) –
zoned
for
open
water
aquaculture
development. Licenses will be considered for
a total of 200ha of aquaculture development in
this zone.
Penneshaw Policy Area
−
−
Penneshaw Aquaculture Zone (570 ha of
coastal waters, within 1 km of coast, in the
west of Cuttlefish Bay and Snapper Point) –
zoned
for
open
water
aquaculture
development. Licenses will be considered for
a total of 200ha of aquaculture development in
this zone, excluding intertidal aquaculture
development .
Licenses will not be considered for remaining
waters of the Penneshaw Policy Area (19,080
ha, from Cape Willoughby, west to Kangaroo
Head).
2.3
Recreation and Tourism
−
Tourism
−
Pennington Bay: scenic area, historic area.
−
D'Estrees Bay and Flour Cask Bay: historic
area, fishing.
−
Cape Gantheaume National Park: scenic area,
fishing, diving, wilderness area.
−
Seal Bay: Australian Sea Lions, scenic area.
This is one of South Australia’s major tourist
destinations for both national and international
tourists.
−
Vivonne Bay: scenic area, jetty fishing,
lighthouse.
−
Kelly Hill conservation park and Flinders
Chase
National Park:
camping.
−
2.4
Pennington Bay: boat fishing. Major species:
Sand Flathead, Yelloweye Mullet, Australian
Salmon, Snook, Garfish, Sweep, Toothbrush
Leatherjacket, Tommy Rough, Trevally and
Silver Drummer.
wilderness,
scenic
area,
Cape Borda: scenic area, historic area.
Scientific Research and Education
−
Pennington Bay and surrounding coastal areas
have been regular research sites since the early
1940's for marine algal collections and
intertidal studies (see Womersley 1948, 1950,
Womersley & Edmonds 1958, 1979).
−
The University of Adelaide has a field
research station in Flinders Chase National
Park.
−
SANPWS monitoring of Australian Sea Lion
and New Zealand Fur Seal populations.
Fishing
−
Vivonne Bay: boat and jetty fishing. Major
species: Black Bream, Sand Flathead,
Yelloweye Mullet, Australian Salmon, King
George Whiting, Snook, Garfish, Sweep,
Toothbrush Leatherjacket, Tommy Rough,
Trevally, Silver Drummer and Southern
Calamari.
Page 225
KANGAROO ISLAND COAST – GANTHEAUME BIOUNIT
2.5
Adjacent Land Use
National and Conservation Parks
−
Cape Hart Conservation Park (1,030 ha)
(SANPWS 1987).
−
Seal Bay Conservation Park (1,911ha), Cape
Gantheaume Conservation Park (4,220 ha),
Cape Gantheaume Wilderness Protection Area
(20,100 ha).
−
Vivonne Bay Conservation Park (1,481 ha)
(SANPWS 1987).
−
Flinders Chase National Park (32,600 ha),
Ravine des Casoars Wilderness Protection
Area (41,320 ha).
−
Kelly Hill Conservation Park (2,180 ha), Cape
Bouguer Wilderness Protection Area (5,530
ha).
Agriculture/Industry
Shipwrecks
−
The west coast of Kangaroo Island is an area
of significant historical and cultural value, due
primarily to the number and density of
shipwrecks and the associated large loss of life
(B. Jefferies, pers.comm.). The wrecks in this
area include the `Loch Sloy', `Loch
Vennachar', `Montebello', `Mars', and the
`Emily Smith'. This region has considerable
potential for a maritime heritage trail, similar
to Wardang Island.
−
`Loch Vennachar' was one of the finest and
fastest three-masted iron ships built at
Glasgow in 1875. It disappeared in 1905 in
the vicinity of the Neptune Islands. A
decomposed body was later found in West
Bay of Kangaroo Island. The ship remains
were found in 1976, 1 km north of West Bay.
The remains are relatively untouched by
salvage operations which make them of
significant archaeological value.
−
`Montebello' was a three-masted iron barque,
built in France in 1900. The vessel was under
charter to the South Australian Farmers Union
when it was wrecked off the south coast of
Kangaroo Island while sailing from Hobart to
Port Pirie. A storm forced the ship onto the
rocks on 18 November 1906 near Stun'Sail
Boom River. The `Montebello' was quickly
broken up by the storm and many of the
remains were scattered on the sea bed. All
persons survived. This is a spectacular dive
but access can be dangerous due to the
Southern Ocean swell.
−
`Osmani’ was lost in 1853, off Point Tinline,
Destres Bay and is protected under
Commonwealth legislation.
3
CURRENT CONSERVATION STATUS
OF THE GANTHEAUME BIOUNIT
Those areas not designated in conservation and
national parks are mainly agricultural.
Urban Centres
−
Vivonne (population <250).
2.6
Features
Significant Cultural or Historical
Aboriginal
−
Not known.
European
−
There is a whaling station located in between
the Harriet River mouth and Point Ellen,
Vivonne Bay/Flour Cask Bay. It operated in
the early 1840's and the area was later used as
a landing site in the expanding pastoralism
years in the 1880's. It is of State Heritage
significance.
−
Marine Reserves
Seal Beach Aquatic Reserve (1,140 ha)
−
Marine Parks
None
−
Marine Sanctuaries
Seal Beach Aquatic Reserve (as above)
Page 226
KANGAROO ISLAND COAST – GANTHEAUME BIOUNIT
−
Kangaroo Island Rivers (Chapmans, Harriet,
Eleanor, Western and Middle Rivers and all
waters within a 50 metre radius of the mouths
of those rivers).
4
AREAS OF HIGH CONSERVATION
VALUE
IN
THE
GANTHEAUME
BIOUNIT
Hooded Plover, Osprey, White-bellied Sea
Eagle, Eastern Reef Egret, protected waterbirds
– 10 species), economic (fisheries-Southern
Rock Lobster, Abalone), social (recreationKelly Hill Conservation Park), national
(Wetlands of National Importance–Grassdale
Lagoons and South West River, Register of the
National Estate–Kelly Hill Conservation
Park), practicality (insulation, accessibility,
compatibility-adjacent to Cape Bouguer
Wilderness Protection Area, Kelly Hill
Conservation Park).
Flinders – Ravine des Casoars
Cape Kersaint – Vivonne Bay
Netting Closures
−
Prime
IUCN
Conservation
Values:
biodiversity,
rare
and
endangered
species/habitats, aesthetic values, cultural
values (IUCN Category IB).
IUCN
Identification Criteria: naturalness (not
subject to human induced change, wilderness
values), biogeographic (geological monumentWest Bay, Cape du Couedic, Remarkable
Rocks), ecological (importance for Southern
Rock Lobster, Abalone, breeding sites for NZ
Fur Seal –Cape du Couedic, North Casuarina,
haul out sites for Australian Sea Lions–Cape
du Couedic, North and South Casuarina, West
Bay Island, high diversity of marine flora and
fauna, reefs, estuaries – North West,
Breakneck, Sand, Rocky River, Stun'sail Boom
River, threatened waterfowl and seabirds–
Hooded Plover, White-bellied Sea Eagle, Redcapped Plover, protected waterbirds – 6
species), economic (fisheries-Southern Rock
Lobster, Abalone), social (recreation-Flinders
national
Park,
heritage–Cape
Borda,
shipwrecks-`Loch Sloy', `Loch Vennachar',
`Montebello', `Mars', `Emily Smith', `Portland
Maru'), scientific (Seal Bay, University of
Adelaide field research station), national
(Wetlands of National Importance–Flinders
Chase National Park), practicality (insulation,
accessibility, compatibility-adjacent to Ravine
des Casoars Wilderness Protection Area,
Flinders Chase National Park).
Cape Bouguer – Kelly Hill
−
Prime
IUCN
Conservation
Values:
biodiversity,
rare
and
endangered
species/habitats, aesthetic values, cultural
values (IUCN Category IB).
IUCN
Identification Criteria: naturalness (not
subject to human induced change, wilderness
values), biogeographic (geological monumentRemarkable Rocks), ecological (importance
for Southern Rock Lobster, Abalone, haul out
sites for NZ Fur Seals and Australian Sea
Lions–Cape Bouguer, high diversity of marine
flora and fauna, reefs, estuaries–South West
River, threatened waterfowl and seabirds–
−
Prime IUCN Conservation Values: rare and
endangered
species/habitats,
research/education, biodiversity, social values
(IUCN Category IA). IUCN Identification
Criteria: naturalness (not subject to human
induced
change,
wilderness
values),
biogeographic (geological monument-Point
Ellen), ecological (importance for Southern
Rock Lobster, Abalone, breeding sites for
Australian Sea Lions–Seal Bay, haul out sites
for NZ Fur Seals–Seal Beach, high diversity of
marine flora and fauna, reefs, estuaries–
Eleanor River, Harriet River, threatened
waterfowl and seabirds–Hooded Plover, Whitebellied Sea Eagle), economic (tourism – Seal
Bay, fisheries-Southern Rock Lobster,
Abalone), social (recreation-Vivonne Bay and
Seal Bay Conservation Parks), national
(Wetlands of National Importance, Register of
the
National
Estate–Vivonne
Bay
Conservation Park, Seal Bay), practicality
(insulation,
accessibility,
compatibilityadjacent to Vivonne Bay Conservation, Seal
Bay Conservation Park and Aquatic Reserve).
Cape Gantheaume
−
Prime IUCN Conservation Values: rare and
endangered species/habitats, biodiversity,
research, social values (IUCN Category IA).
IUCN Identification Criteria: naturalness
(not subject to human induced change,
wilderness values), biogeographic (geological
monument-Remarkable Rocks), ecological
(importance for Southern Rock Lobster,
Abalone, significant breeding sites for NZ Fur
Seals–Cape Gantheaume, breeding sites for
Australian Sea Lions–Cape Gantheaume, high
diversity of marine flora and fauna, reefs,
estuaries, threatened waterfowl and seabirds–
Hooded Plover, White-bellied Sea Eagle),
economic (fisheries-Southern Rock Lobster,
Abalone),
social
(recreation-Cape
Gantheaume Conservation Park), national
(Register of the National Estate–Cape
Gantheaume Conservation Park), practicality
(insulation,
accessibility,
compatibilityPage 227
KANGAROO ISLAND COAST – GANTHEAUME BIOUNIT
adjacent
to
Gantheaume
Protection
Area,
Cape
Conservation Park).
Wilderness
Gantheaume
D’Estres Bay
−
Prime
IUCN
Conservation
Values:
biodiversity,
rare
and
endangered
species/habitats, cultural, social values (IUCN
Category II). IUCN Identification Criteria:
naturalness (not subject to human induced
change, wilderness values), biogeographic
(largest seagrass meadows on south coast of
Kangaroo Island), ecological (extensive
seagrass meadows, estuaries–Willson River,
threatened waterbirds breeding sites, migratory
waders and seabirds – Hooded Plover, Osprey,
Fairy Tern, Pied and Sooty Oystercatcher,
Caspian Tern, Red-capped Plover), economic
(fisheries-Southern Rock Lobster, Abalone),
social
(recreation-Cape
Gantheaume
Conservation Park, Flour Cask Bay-Whaling
Station,
shipwrecks-`Osmani'),
scientific
(Pennington Bay-marine studies), national
(Wetland of National Importance-D’Estres
Bay, Register of the National Estate–Cape
Gantheaume Conservation Park), practicality
(insulation,
accessibility,
compatibilityadjacent to Cape Gantheaume Conservation
Park).
Submarine Canyons & Basement Highs
−
Prime
IUCN
Conservation
Values:
biodiversity, research (IUCN Category IB).
IUCN Identification Criteria: naturalness
(not subject to human induced change,
wilderness values), biogeographic (deepwater
canyon habitat-Sprigg and Murray Canyons,
basement highs-Sanders and Carter Knoll),
ecological (importance for preservation of
unknown canyon ecosystems and habitats, reef
flora and fauna of basement highs), economic
(fisheries-unknown), national (potential for
listing on the Register of the National Estate),
practicality (insulation from external threats).
Cape Hart
−
Prime IUCN Conservation Values: aesthetic
values biodiversity (IUCN Category III).
IUCN Identification Criteria: naturalness
(not subject to human induced change,
wilderness values), ecological (importance for
Southern Rock Lobster, Abalone, high
diversity of marine reef flora and fauna),
economic (fisheries-Southern Rock Lobster,
Abalone), social (recreation-Cape Hart
Conservation Park, coastal aesthetic values),
practicality
(insulation,
accessibility,
compatibility-adjacent
to
Cape
Hart
Conservation Park).
Page 228
KANGAROO ISLAND COAST – CASSINI BIOUNIT
XXVI
MARINE BIOGEOGRAPHY AND CONSERVATION VALUES OF THE CASSINI BIOUNIT
This biounit extends from Cape Borda to North Cape, and covers an area of 45,760 ha and represents 24% of the
Kangaroo Island coastline (111 km). It faces northwards into the Investigator Strait.
MARINE BIOGEOGRAPHY
1
3
Major Inshore Habitats
OCEANOGRAPHY
This area generally experiences moderate wave
energies, with coves and beaches being of low to
moderate wave energy.
2
GEOLOGY
AND
GEOMORPHOLOGY 51
BIOLOGY
−
Major intertidal habitats in the region include
mostly rocky cliffs and shores, estuaries and
some sandy beaches.
−
Of the total inshore subtidal habitats mapped
in the biounit (15,868 ha), sandy bottoms
comprise 12,943 ha (81.6%), reefs comprise 2
263 ha (14.3%), and seagrass meadows
comprise 662 ha (4.2%).
COASTAL
The Cassini Biounit is dominated by moderate to
high sea cliffs usually fronted by shore platforms.
Shingle and boulder beaches occur in several
locations and are associated with most sand beaches
(eg. Dashwood, Smith and, to a lesser extent, Boxing
Bays). All beaches are composed of quartz carbonate
sands, and are usually fronted by transverse bar and
rip surf zones. The beaches are susceptible to winter
flooding of creeks across the foreshore and storm
wave erosion and overwash which in turn leads to
scarping of the parallel foredunes.
Emu Bay is bounded by fossil rich Cambrian shales
backed by 20 to 50 m high scarped Pleistocene dune
calcarenite. The 5 km long low energy beach is
prone to storm wave erosion and overwash. The
foredune is semi-stable, but dune transgression is
prevented by the backing dune calcarenite.
Boxing Bay is 2 km in length and similar to Emu
Bay. However, a deficiency of the fine quartzcarbonate sand (40% carbonate) plus the
occurrence of conglomerate boulders and extensive
intertidal calcarenite provide a significant contrast
to Emu Bay.
Major Benthic Communities
•
Macroalgal
−
The rocky shores and reefs of the north west
coast of Kangaroo Island, west of North Cape,
generally experience moderate wave exposure
but strong swell and tidal currents (through
Investigator Strait). On these exposed shores,
headlands and reefs (eg. Cape Borda, Cape
Torrens) are dominated by large, robust,
brown algae (ie. Scytothalia dorycarpa,
Carpoglossum confluens, Ecklonia radiata,
Acrocarpia paniculata, Seirococcus axillaris,
Cystophora platylobium), with an understorey
of red algae (ie. Plocamium, Callophyllis,
Phacelocarpus), green algae (Caulerpa
flexilis, C.longfolia) and coralline algae (eg.
Haliptilon, Metagoniolithon). In moderate to
sheltered areas (eg. Western River Cove,
Stokes Bay, Emu Bay), reef areas tend to be
dominated by Seirococcus axillaris, with
Ecklonia radiata, Scytothalia, Melanthalia
and species of Cystophora (C.moniliformis,
C.retorta, S.siliquosa, C.expansa) as subdominants, and understorey species of red
algae
(Plocamium,
Phacelocarpus,
Sonderopelta, Cladurus elatus) and species of
Dictyotales (Zonaria, Dictyota).
51
From Kangaroo Island Coast Protection District Study Report
(Edwards 1987).
Page 229
KANGAROO ISLAND COAST – CASSINI BIOUNIT
•
Seagrasses
−
Seagrass meadows are sparse in this region
and are restricted to the sheltered embayments
(Emu Bay, Stokes Bay, Western River Cove)
and in shallow offshore waters. Sandy
sediments are commonly colonised by species
of Posidonia (P.sinuosa, P.angustifolia), in
shallow water and Heterozostera tasmanica,
Amphibolis
antarctica
and
Halophila
australis, which tend to extend to deeper
waters (ie. 15m). Other species also colonise
sandy sediments, particularly species of
Caulerpa (eg. C.trifaria).
•
−
Cape Torrens Conservation Park
Is a representative example of the spectacular
coastal cliffs of the north coast. Some 57
species of birds have been recorded in the
park. The cliff top coastal vegetation consists
of Acacia paradoxa with some Olearia and
Goodenia spp. The park is on the Register of
the National Estate, and was abolished in 1993
and proclaimed as the Cape Torrens Protection
Wilderness Protection Area under the
Wilderness Protection Act 1992.
•
−
De Mole River Estuary:
has a surrounding stand of Allocasuarina
verticillata, which is an important habitat for
the rare and threatened Glossy Black
Cockatoo. The De Mole River estuary is also
considered to be an area of great scenic beauty
(E. Oks 1986).
•
−
Middle River:
The mouth of Middle River (at Snelling
Beach) has the densest and largest area of
coverage of Sea Rocket (Cackile maritima)
found near any of the river mouths on
Kangaroo Island or the mainland. Wading
birds use the mudflats and lagoon areas for
feeding and breeding.
Rivers and Estuaries
−
Western River estuary.
−
De Mole River estuary.
−
Middle River estuary.
−
There are some twenty other named creeks
and rivers that enter the sea along this section
of the coast.
MARINE CONSERVATION VALUES
1
1.1
•
−
SIGNIFICANT
BIOLOGICAL
PHYSICAL FEATURES
1.2
AND
−
Coastal areas that are considered to be
particularly spectacular include the coast from
Cape Borda to Cape Torrens. This section of
coast has the highest coastal cliffs on
Kangaroo Island (263 m). Snelling Beach is
also a popular viewing area.
−
Cape Torrens Conservation Park (see above).
−
Western River Conservation Park (see above).
Biological
Western River Conservation Park
The Western River estuary and outstanding
coastal cliffs have been conserved in the
Western River Conservation Park (2,364ha).
A total of 78 species of birds have been
recorded in the park.
The estuary and
conservation park is also considered to be an
area of outstanding beauty. The park is on the
Register of the National Estate. Its natural and
wilderness values are also protected as the
Western River Wilderness Protection Area
under the Wilderness Protection Act 1992.
Western River Cove is a very popular diving
location with local dive operators and is
recognised for a wide range of marine habitats
and species (over 270 species), and abundant
fish life (including Leafy Sea Dragons, Telma
Butterfly fish, Old Wives, Blue Devils,
Morwong, Harlequins and Blue Groper).
Physical
Geological Monuments
•
−
Smith Bay:
Striated glacial pavements of Permian age
developed on Early Cambrian strata. A raised
beach along 1k m of coastline. The site has
high teaching value.
•
−
Stokes Bay:
Geomorphological features derived form
Pleistocene
aeolianite
unconformably
overlying
Early
Cambrian
felspathic
sandstone. 300 m of coastline with teaching
and research value.
Page 230
KANGAROO ISLAND COAST – CASSINI BIOUNIT
•
−
Harveys Return:
Spectacular slumping and folding in
metasediments of the Kanmantoo Group.
Distinctive regular layering of black biotiterich and grey quartz-rich bands. 400m of
cliffs and shoreline around a rocky cove with
teaching, research, scientific aesthetic and
recreational value.
Fishing also occurs in Fishing Zone 39, along the
north western coast of the island, and also the
offshore islands in this region (Gambier Islands,
Neptune Islands, and Thistle Island). In 1995/96
and 1996/97, a total of 21 and 31 licensed operators
fished in the area (ie. Fishing Zone 39), catching a
total of 66,188 and 86,753 kg, respectively (or
0.64% and 0.86% of the total catch for the marine
scalefish fishery in South Australian waters).
•
−
Emu Bay - Cape D'Estaing:
Type section of Emu Bay Shale and part of an
outstanding sequence of Early Cambrian
rocks. Two sections of coast 300 m and 1.5
km long with teaching and scientific value.
Marine scalefish fishing in this region includes 1
Salmon purse seining operation along the north coast
of the island, and in the bays. Some line fishing also
occurs along the north coast.
2.2
2
2.1
OTHER VALUES
Commercial Fisheries
Major single species fisheries in this biounit are the
Southern Rock Lobster, and Abalone. This section of
the coast of Kangaroo Island is frequented by license
holders from the mainland as well as those on the
island itself.
−
Cape Cassini Policy Area
−
Inner Cape Cassini Zone (inshore waters from
Point Marsden, west to Cape Dutton,
excluding Stokes Bay, Emu Bay and Boxing
Bay) – zoned to provide for limited coastal
aquaculture development. Licenses will be
considered for a maximum of 60ha of
aquaculture development in this zone,
excluding intertidal oyster culture.
−
Outer Cape Cassini Zone (21,380 ha of
offshore waters from Point Marsden, west to
Cape Dutton) – zoned for R&D open water
aquaculture development. Licenses will be
issues for a total of 12 ha of R&D aquaculture
development in this zone.
−
Cape Cassini Aquaculture Zone (1 000 ha of
offshore waters between Cape Cassini and
Emu Bay) – zoned for open water aquaculture
development. Licenses will be considered for
a total of 200ha of aquaculture development in
this zone.
Marine Scalefish Fisheries
During 1995/96 and 1996/97, 28 and 31
commercial licence holders (made up of Marine
Scalefish and Restricted Marine Scalefish licence
categories) caught commercial marine scalefish
species along the north coast of Kangaroo Island
(ie. Fishing Zone 41), respectively.
License
holders expended approximately 823 and 799 boat
days effort fishing these waters during 1995/96 and
1996/97, respectively. The marine scalefish catch
for this region (ie. Fishing Zone 41) represented
182,476 kg in 1995/96 and 60,654 kg in 1996/97(or
1.76% and 0.60% of the total catch for the marine
scalefish fishery in South Australian waters).
None.
The Kangaroo Island Aquaculture Management Plan
(Gilliland 1996) proposes the following aquaculture
development in this region:
Southern Rock Lobster
In 1995/96 and 1996/97 a total of 8 and 4 licensed
operators fished along the north coast of Kangaroo
Island (ie. Fishing Zone 41). However, the north
western coast of the island, and the offshore islands
in this region (Gambier Islands, Neptune Islands,
and Thistle Island), represent a major region for
lobster fishing in South Australia. In 1995/96 and
1996/97, a total of 51 and 47 licensed operators
fished in the area (ie. Fishing Zone 39), catching
approximately 108,867 and 136,826 kg of lobsters,
respectively (or 2.13% and 2.68% of the total catch
for Southern Rock Lobster in South Australian
waters).
Aquaculture
Cape Torrens Policy Area
−
Inner Cape Torrens Zone (5,310 ha of coastal
waters, within 1 km of the coast, from Cape
Dutton, west to Ravine Des Casoars,
excluding Snelling Beach and waters adjacent
to Western River and Cape Torrens
Wilderness Protection Areas) – zoned for
limited coastal aquaculture development.
Licenses will be considered for a total of 60ha
of aquaculture development in this zone,
excluding intertidal oyster culture.
Page 231
KANGAROO ISLAND COAST – CASSINI BIOUNIT
−
−
Outer Cape Torrens Zone (21,340 ha of
offshore waters from Cape Dutton, west to
Harvey’s Return, Ravine Des Casoars) –
zoned for R&D open water aquaculture
development. Licenses will be considered for
a total of 12ha of R&D aquaculture
development in this zone.
Cape Torrens Aquaculture Zone (1 000 ha of
offshore waters between Snelling Beach and
Western River Cove) – zoned for open water
aquaculture development. Licenses will be
considered for a total of 200 ha of aquaculture
development in this zone.
−
Western River Cove and Stokes Bay: fishing,
camping, swimming, surfing, shacks. The
eastern part of Stokes Bay has a small beach
area that is protected by the offshore reef and
is consequently a safe swimming area.
−
Emu Bay: boating, swimming, fishing, scenic
area, diving in underwater caves and around
Cape D'Estaing.
−
Snelling Beach is a relatively safe swimming
beach.
−
Cape Torrens Conservation Park has
particularly spectacular diving and coastal
scenery.
−
Cape Cassini: diving, scenic area.
−
SCUBA diving: there are many popular diving
sites on the north coast of Kangaroo Island,
which offer accessible, all-weather diving.
The whole of the north coast of Kangaroo
Island, including Western River Cove, contain
many popular and recognised dive spots and
are listed in `Dive South Australia: The Best
Dive Sites in South Australia’ (Diving
Industry Association of South Australia).
Flinders Chase Policy Area
−
Flinders Chase Policy Area (waters adjacent to
the Ravine Des Casoars Wilderness Protection
Area and Flinders Chase National Park) –
zoned to protect conservation areas. Licenses
will not be considered for aquaculture
development in this zone.
2.3
Recreation and Tourism
Fishing
−
−
−
−
Stokes Bay: boat and rock fishing. Major
species: Sand Flathead, Yelloweye Mullet,
Australian Salmon, King George Whiting,
Snapper, Snook, Garfish, Sweep, Toothbrush
Leatherjacket, Southern Rock Lobster,
Tommy Rough, Trevally, Silver Drummer and
Calamari.
Western Cove is a particularly popular diving
location with local dive operators (eg.
Kangaroo Island Diving Safaris) and is
recognised for a wide range of marine habitats
and species (over 270 species), and abundant
fish life (including Leafy Sea Dragons, Telma
Butterfly fish, Old Wives, Blue Devils,
Morwong, Harlequins and large Blue Groper).
Sea lions and seals also often frequent the
sheltered inlets and rock pools on the north
coast of the island.
Emu Bay: jetty, boat and rock fishing. Major
species: Sand Flathead, Yelloweye Mullet,
Australian Salmon, King George Whiting,
Snapper, Snook, Garfish, Sweep, Toothbrush
Leatherjacket, Tommy Rough, Trevally, Silver
Drummer and Calamari.
2.4
Tourism
−
Scott Cove and Harveys Return are both
within Flinders Chase National Park and are
popular coastal destinations for visitors enroute to the Cape Borda lighthouse - scenic
and historic area.
2.5
Scientific Research and Education
Not known.
Adjacent Land Use
National and Conservation Parks
−
Small section of Ravine des Casoars
Wilderness Protection Area, by Cape Borda.
−
Cape Torrens Wilderness Protection Area (751
ha) (SANPWS 1987).
Snug Cove: boating, fishing, diving.
Page 232
KANGAROO ISLAND COAST – CASSINI BIOUNIT
−
−
Western River Conservation Park (167 ha),
Western River Wilderness Protection Area
(2,373 ha) (SANPWS 1987).
−
`Fairfield’ , lost in 1874 off Cape Cassini.
−
`Portland Maru’, a steel steamship, measuring
385 feet, built in Japan in 1919. It was
wrecked off Cape Torrens in 1935, and has
been recommended for protection under
Commonwealth legislation. The wreck is a
very popular dive site and is listed in `Dive
South Australia: The Best Dive Sites in South
Australia’ (Diving Industry Association of
South Australia).
3
CURRENT CONSERVATION STATUS
OF THE CASSINI BIOUNIT
Lathami Conservation Park (1,190 ha).
Agriculture/Industry
Most of the adjacent land in this biounit is used for
agricultural purposes.
Urban Centres
There are no large urban centres along this section of
the coast. However, holiday shacks and private
developments have occurred opposite most of the
pocket beaches. Public access and facilities occur at
the major beaches of Western River Cove, Snelling
Beach and Stokes Bay.
2.6
Features
Significant Cultural or Historical
Aboriginal
−
Sites of cultural significance have been
identified along the Western River.
−
Marine Reserves
None
−
Marine Parks
None
−
Marine Sanctuaries
None
Netting Closures
−
Kangaroo Island Rivers (Chapmans, Harriet,
Eleanor, Western and Middle Rivers and all
waters within a 50 metre radius of the mouths
of those rivers).
4
AREAS OF HIGH CONSERVATION
VALUE IN THE CASSINI BIOUNIT
European
−
−
Many of the geographical names along this
section of Kangaroo Island were named by the
French explorer, Baudin, as detailed in
Cockburn (1984).
Harvey's Return was discovered by two men,
Whalley and Harvey in 1834, when searching
for a place to land near Cape Borda (Cockburn
1984). In 1858 the Cape Borda Lighthouse
was constructed.
Shipwrecks
There are 3 wrecks that are located in this area,
many of which are of significant historical value and
are also protected under Commonwealth legislation:
−
`Fides' was a three masted wooden barque
built at Christianastadt, Finland in 1857. It
was wrecked Snug Cove whilst on its journey
to Port Adelaide from London in 1860. The
wreck is situated against the cliffs in about 10
metres of water on a gravel seabed. Vast
numbers of beer keg taps have been recovered
from the site as well as bottles, fruit preserved
in bottles, bullets and an ingot of metal. Only
fragments of glass and the occasional tap can
now be found on the site. There is an
interpretive plaque near the wrecksite.
Cape Torrens – Harry’s Return
−
Prime
IUCN
Conservation
Values:
biodiversity,
rare
and
endangered
species/habitats, cultural, aesthetic values
(IUCN Category IA). IUCN Identification
Criteria: naturalness (not subject to human
induced change, wilderness values, coastal
cliffs), biogeographic (representative habitats,
geological
monument–Harveys
Return),
ecological (rare and threatened species–
Glossy Black Cockatoo, haul out sites for NZ
Fur Seals and Australian Sea Lions, habitats
for marine flora and fauna, reefs, estuaries–
De Mole River, 57 bird species), economic
(fisheries-Southern Rock Lobster, marine
scalefish fisheries), social (diving and
recreation,
Cape
Torrens
Wilderness
Protection Area, shipwrecks-`Portland Maru'
at Cape Torrens), scientific (Harveys Return),
national (Register of the National Estate–Cape
Torrens Wilderness Protection Area),
practicality
(insulation,
accessibility,
compatibility-adjacent to Cape Torrens
Wilderness Protection Area).
Page 233
KANGAROO ISLAND COAST – CASSINI BIOUNIT
Smith Bay
Western River Cove – Snug Cove
−
−
Prime
IUCN
Conservation
Values:
biodiversity,
rare
and
endangered
species/habitats, cultural, aesthetic values
(IUCN Category IA). IUCN Identification
Criteria: naturalness (not subject to human
induced change, wilderness values, coastal
cliffs),
biogeographic
(representative
habitats), ecological (haul out sites for NZ Fur
Seals and Australian Sea Lions, habitats for
marine flora and fauna, reefs, estuaries–
Western River, 78 bird species), economic
(commercial dive tourism, fisheries-Southern
Rock Lobster, marine scalefish fisheries),
social (diving-Western River Cove, recreationWestern River Cove, Snug Cove, aboriginal
heritage–Western River region, shipwrecks`Fides’ at Snug Cove, Western River'),
national (Register of the National Estate–
Western River Wilderness Protection Area),
practicality
(insulation,
accessibility,
compatibility-adjacent to Western River
Wilderness Protection Area and Conservation
Park).
Stokes Bay
−
Prime
IUCN
Conservation
Values:
biodiversity,
rare
and
endangered
species/habitats, cultural, social values (IUCN
Category IA). IUCN Identification Criteria:
naturalness (not subject to human induced
change, wilderness values), biogeographic
(geological
monument–Stokes
Bay,
representative habitats), ecological (haul out
sites for NZ Fur Seals and Australian Sea
Lions, habitats for marine flora and fauna,
reefs), economic (commercial dive tourism,
fisheries-Southern Rock Lobster, marine
scalefish fisheries), social (diving-Stokes Bay,
recreation-fishing, shipwrecks-Stokes Bay'),
national (potential for listing on the Register
of the National Estate–Stokes Bay),
practicality
(accessibility,
compatibilityadjacent to Lathami Conservation Park).
Prime IUCN Conservation Values: social
values, biodiversity, rare and endangered
species/habitats, cultural (IUCN Category II).
IUCN Identification Criteria: naturalness
(not subject to human induced change),
biogeographic (representative habitats–large
reef coastal reef platform, geological
monument–Smith Bay), ecological (haul out
sites for NZ Fur Seals and Australian Sea
Lions, habitats for marine flora and fauna,
reefs), economic (commercial dive tourism,
fisheries-marine scalefish fisheries), social
(diving, recreation-Emu Bay, heritage–
shipwrecks-`Fairfield’ at Cape Cassini),
national (potential for listing on the Register
of the National Estate), practicality
(insulation).
Emu Bay and Boxing Bay
−
Prime
IUCN
Conservation
Values:
biodiversity,
rare
and
endangered
species/habitats, cultural, social values (IUCN
Category II). IUCN Identification Criteria:
naturalness (not subject to human induced
change),
biogeographic
(representative
habitats–largest seagrass meadows on north
east coast, geological monument – Emu Bay to
Cape D’Estaing), ecological (haul out sites for
NZ Fur Seals and Australian Sea Lions,
habitats for marine flora and fauna, reefs,
seagrass meadows), economic (commercial
dive tourism, fisheries-marine scalefish
fisheries), social (diving-Cape D’Estaing,
recreation-Emu Bay, heritage – shipwrecksEmu Bay), national (potential for listing on the
Register of the National Estate), practicality
(accessibility).
Page 234
SOUTH-EAST COAST REGION
MARINE BIOGEOGRAPHY AND CONSERVATION VALUES OF
THE SOUTH EAST COAST
MARINE BIOGEOGRAPHY
1.
2.
3.
4.
5.
The South East Coast
Oceanography
Climate
Coastal Geomorphology and Landforms
Biology
MARINE CONSERVATION VALUES
1.
2.
3.
Significant Biological and Physical Features
Significant Cultural and Historical Features
Current Conservation Status of the South East Coast
BIOUNITS
1.
2.
3.
4.
Coorong
Canunda
Nene
Piccaninnie
Page 235
SOUTH-EAST COAST REGION
MARINE BIOGEOGRAPHY AND CONSERVATION VALUES OF
THE SOUTH EAST COAST
MARINE BIOGEOGRAPHY
1
THE SOUTH EAST COAST
The South East coast extends from the Murray
Mouth eastwards, to at least the Victorian border and
represents a coastal distance of approximately 390
kilometres. The coastal waters of this region
represent some of the most diverse and productive
waters of South Australia. As such, this region
contains one of the highest centres of algal or
seaweed diversity in the world. This diversity is in
part due to the overlap of two major biogeographical
regions. Unlike rest of the South Australia, the
fauna and flora east of Robe is akin to the biota of
the cooler waters of Victoria and Tasmania, while
west of Robe the biota is typical of the warmer
waters of western South Australia and Western
Australia.
The South East coast is also a region of considerable
coastal productivity, providing some of South
Australia's most productive fisheries, in particular
the Southern Rock Lobster and Abalone fisheries.
This productivity is primarily a result of the unique,
nutrient-rich coastal upwellings which occur in this
region. These nutrient-rich upwellings represent the
most significant upwellings to be found along the
whole of the Southern Australian coastline.
The South East coast is also characterised by
spectacular coastal landforms such as the Coorong
lagoons, which not only support extensive
populations of migratory waterbirds, but also
preserve important records of our Pleistocene
history. For the most part, the coast is oriented in a
south and southwesterly direction into the Southern
Ocean and experiences some of the highest wave
energies (eg. Canunda region) in South Australia..
1.1
Coast
Biogeography of the South East
Along the southern coast of Australia, marine
biogeographers recognise a major biogeographic
region, known as the Flindersian Province, which
extends from south-west Western Australia to
southern New South Wales (Bermagui) and includes
the waters of Victoria and Tasmania. Within this
broad region, the coastal waters of the south east
coast of Australia (east of Robe) are recognised as
cold temperate, in contrast to the warm to cool
temperate waters of the Great Australian Bight (west
of Robe) (Womersely & Edmonds 1958).
At the boundary of this major biogeographical
region, the cold temperate marine fauna and flora of
the lower South East coast is unlike any other coastal
region of South Australia. This distinct
biogeographical region (known as the cold-water
Maugean Subprovince) is characterised by slightly
lower temperatures and different species
assemblages, compared to that found west of Robe.
The Maugean Subprovince is characterised by the
following biological features:
−
a virtual absence of barnacles in the upper and
mid eulittoral zones, which are populated
mainly by molluscs (especially chitons);
−
prominence of the red alga Porphyra
columbiana in the mid eulittoral zone during
winter;
−
presence of the giant, cold water, brown algae
or kelps, such as Durvillaea potatorum (Bull
Kelp) and Macrocystis angustifolia; and the
−
presence of other cold water algae such as
Myriogloia sciuris, Eudesme harveyana,
Codium fragile, Grateloupia sp. and
Pleonosporium comatum.
Within the Maugean Subprovince, the South East
coastal and marine ecosystems encompass 2 welldefined biogeographical regions known as the
Coorong Bioregion and the Otway Bioregion. The
Coorong coast is encompassed within the Coorong
Bioregion, which extends from Port Elliot to Cape
Jaffa (IMCRA 1997). However, the lower South
East region, from Cape Jaffa to the Victorian
border, falls within another marine biogeographic
known as the Otway Bioregion, which extends
from Cape Jaffa to slightly north of Apollo Bay
(Victoria) and King Island (Tasmania) (IMCRA
1997).
A complete physical and ecological
biogeographic description of the Coorong
Bioregion and Otway Bioregion, including marine
fauna and flora, has been described by IMCRA
(1997).
Page 236
SOUTH-EAST COAST REGION
Based on coastal geology, wave climate, and coastal
orientation, Short and Fotheringham (1986),
identified three coastal geomorphological regions (or
subprovinces) for the South East coast. 52
1
2
3
Coorong Subprovince (from Middleton,
Encounter Bay to Cape Jaffa, 190 km).
Robe Range Subprovince (from Cape Jaffa to
Cape Banks, 140 km).
Port MacDonnell Subprovince (from Cape
Banks to the Victorian border, 60 km).
These coastal subprovinces correspond to 4 finerscale marine biogeographical regions or biounits:
Despite this, surface waters exhibit a seasonal cycle
of minimum salinity and maximum temperature
(35.2%., 18oC) during summer, and maximum
salinity and minimum temperature (35.8%., 14oC)
during winter (Lewis 1981). During winter, the
water column is well mixed (35.6%.,14oC) with
stratification beginning in October.
From
December, the lower layer exhibits decreased
temperatures (11-12oC) and salinity (35.2%) due to
the influence of upwellings. Shallow waters and
rock pools in calmer areas are subject to a greater
range in temperatures (Womersley & Edmonds
1958).
2.3
1.
2.
3.
4.
2
2.1
Coorong Biounit (from Port Elliot to Cape
Jaffa,)
Canunda Biounit (from Cape Jaffa to Cape
Banks)
Nene Biounit (from Cape Banks to Cape
Northumberland)
Piccaninnie
Biounit
(from
Cape
Northumberland to Victorian border)
OCEANOGRAPHY
Wave Climate
The whole of the South East coast is subject to high
deepwater wave energy attenuated by an offshorenearshore gradient. This results in varying wave
energies along the coast. As such, wave energy
ranges from very high, at the northern end of
Younghusband Peninsula, the Robe Range, and
near the Victorian Border, to moderate in Guichen
Bay and Rivoli Bay, and to low in Lacepede, Bucks
and MacDonnell Bays. Massive beach erosion and
foredune scarping is high for most of the South
East coast owing to storm surges. A predominant
southwest swell also impinges on the coast for
most of the year.
Tides are generally micro-tidal in range and semidiurnal, with a moderate diurnal inequality.
2.2
Water Temperature and Salinity
Ocean surface temperatures along the South East
coast are consistently lower than for other coastal
regions of South Australia (Womersley &
Edmonds 1958). However, annual temperature and
salinity fluctuations are complicated, due in part to
local upwellings.
Currents and Upwellings
The considerable coastal productivity of the South
East coast is primarily a result of the presence of
nutrient-rich upwellings. The upwellings along this
region represent the most significant coastal
upwellings to be found along the whole of the
Southern Australian coastline, and are due, in part,
to the meterological conditions of the region.
The movement of anticyclonic air streams, from
west to east, induce a general easterly baroclinic
water transport along the southern coast and within
this, numerous anticyclonic and intermittent eddies
(Bye 1970). The centres of the anticyclonic air
streams are considerably further north in winter
than in summer. In the lower South East, this
frequently causes a north-westerly wind in winter
and a south easterly wind in summer. The latter
acts on the thermohaline structure of the water
producing a current in the warmer upper layers
which moves towards the coast and is then
deflected away. As a result, there is upwelling of
colder, nutrient-rich, less saline water.
Three centres of upwelling have been identified in
the South East region: Robe, Southend and Port
MacDonnell (Lewis 1981).
2.4
Groundwater Drainage
In the lower South East lie two important aquifers
below the surface water system. The first is an
unconfined aquifer in the Gambier Limestone, and
below this, is a confined aquifer in the Dilwyn
Formation. Beach springs are found along the
coastline east of Port MacDonnell and offshore
seepage occurs between Port MacDonnell and the
Victorian border and also, in the Robe-Beachport
area. Consequently, any pollution of the aquifer is
likely to have some impact on the marine
environment, depending on the degree of dilution
achieved. 53
53
52
From South East Coast Protection District Study Report (UEPG
1982).
South East Coast Protection District Study Report
(UEPG 1982).
Page 237
SOUTH-EAST COAST REGION
3
CLIMATE
The South East is characterised by a typical `cool
temperate', mesothermal climate, with cool, wet
winters and warm, dry summers. Beachport has
one of the highest influential rainfall periods (nine
months), in the state (Gentili 1972). However, the
entire South East coast suffers from a marked lack
of moisture due to high evaporation rates.
4
COASTAL GEOMORPHOLOGY
LANDFORMS
AND
There are five major macro-scale landform elements
recognised along the South East coast (Short & Hesp
1984):
4.1 Outer Dune Barrier Complexes
Younghusband Peninsula and Robe.
of
Younghusband Peninsula began as a barrier
complex formed during a relatively high sea level
around 80,000 years B.P. resulting in Pleistocene
calcreted basal unit overlaid by Holocene noncemented dunes.
Outcrops of this calcreted
component can be seen along the Robe range and
Beachport (Von der Borch 1976).
Robe Range is a barrier complex formed during
low sea level periods between 220,000 and 180,000
years B.P, and has been subsequently uplifted and
surrounded by high sea levels (Sprigg 1979). It is
subject to hind-dune instability due to spatial
variations in breaker wave energy, nearshore
gradients and beach and foredune instability. The
most unstable areas are mid-Younghusband
Peninsula
and
Canunda,
with
Canunda
experiencing the highest breaker wave energy
along the southeast coast (Short & Hesp 1984).
Moderate breaker wave energy and rip circulation
has caused fore-dune erosion and consequential
hind dune instability between Nora Creina and
Beachport.
4.2 Beach-Ridge Plains of Lacepede, Guichen
and Rivoli Bays
The Beach-Ridge Plains may be a unique
expression of sea level changes during the
Holocene, and as such it represents a geologically
significant area. More than 7,000 years ago the
inter-barrier depression between the Robe and
Woakwine Ranges was breached by the sea,
causing the Lower River Murray Valley to flood,
and the Younghusband Peninsula and the Robe
Range to become nearshore islands. Deposition of
Holocene sediments caused the inter-barrier
depression to become a tidal estuary, with openings
in the outer barrier.
A subsequent high rate of sediment supply in the
Lacepede, Guichen and Rivoli embayment,
combined with low to moderate breaker wave
energy, resulted in the closure of the estuaries and a
prograded coastline backed by plains of low
stranded dunes extending from the Woakwine
Range to the present shoreline (Short & Hesp
1984).
Generally, the foredune complexes and their
backing beach-ridge systems are relatively stable.
Higher breaker wave energies may contribute to
some instability in Guichen Bay.
4.3 Coorong and Robe Range-Woakwine Range
Depressions.
The Coorong Depression extends from Murray lakes
to Cape Jaffa, and contains the Coorong Lagoon,
ephemeral pipe clay lakes and swamps. 5,000 years
ago, this depression was an estuarine environment.
Subsequent infilling of the estuary with the
Lacepede Bay beach ridge occurred and together
with the closing off of the Southern Coorong to the
sea, created the ephemeral saline environments of
the Kingston Lake Chain.
The Robe Range-Woakwine Depression consists of
a corridor of estuarine, clay and shell beds, deposited
during the mid-Holocene when the corridor
contained an unconfined lagoon, with estuaries at
Guichen and Rivoli Bays. Infilling of the estuaries
resulted in the corridor formation.
4.4 Stranded Pleistocene Barriers and Relict
Coast of the Robe Range Outer Barrier.
This landform occurs in three major areas:
1
landward of the Coorong inter-barrier
depression: relatively stable and not subject to
active coastal processes.
2
as the Woakwine Range stranded barrier
complex: relatively stable and not subject to
active coastal processes.
3
as outcropping calcrete remnants along the
Robe Range: remnants found as rocky
headlands, offshore islands, wave-cut platforms
and reefs.
Page 238
SOUTH-EAST COAST REGION
4.5 Tertiary Limestone Plain of the Lower
Southeast.
Characterised by low undulating plain, sometimes
outcropping at the coast as reefs and rocky
headlands, and sometimes capped with Holocene
beach and dune deposits. Depressional areas are
relatively common and contain swamps and peat
deposits.
Holocene Beach Dune Systems
Offshore reefs along the coast reduce wave energy
and interrupt sediment transport, influencing the
morphology of the beach dune systems such that
relatively low energy, stable shoreline in the lee of
the reefs occurs with a tendency to build shingle
beach ridges. Shingle beach-ridges are common
near Blackfellows Caves, and in Umpherstone,
Blanche, Racecourse and Riddoch Bays.
Rocky Coast
This comprises the Gambier limestone formations
which consists of limestone outcrops at the coast
producing dominant cliffed headlands, and the low,
gently undulating plain developed over the Gambier
limestone back from the coastline. Major coastal
outcroppings occur at Bucks Bay, Blackfellows
caves, Douglas Point and Cape Northumberland.
5
5.1
BIOLOGY
General Ecology
A diverse range of marine and estuarine habitats are
represented along the South East coast. These
include: rocky shores, seagrass meadows, sandy
beaches and dunes, estuaries and lagoons, sheltered
embayments, and subtidal and offshore reefs. No
stands of the Grey Mangrove, Avicennia marina are
present in this region. The coastal region of the
South East coast is typically dominated by
extensive offshore, parallel, flat platform aeolianite
reef systems which extend offshore from,
approximately 350 km to the continental shelf
margin in the Coorong and Murray Mouth region
(ie. south of Kangaroo Island), to a narrow
continental margin, approximately 10 km wide in
the coastal areas south of Robe. This reef system
generally extends from, the 11 metre depth contour
off the Coorong, to approximately 8 metres in the
coastal areas south of Robe. In low wave energy
areas, these offshore reefs make possible the
existence of seagrass beds which also provide food
and shelter for numerous organisms, including the
Southern Rock Lobster (Jasus edwardsii) (eg.
Kingston).
The waters of the South East coast, contain some of
the highest levels of marine biodiversity and also,
productivity in South Australia. East of Robe,
nearshore marine habitats are characterised by cold
temperate fauna and flora (ie. the Maugean
Subprovince of Tasmania, Victoria, south-east South
Australia), particularly the presence of the kelps,
Macrocystis angustifolia and Durvillea potatorum,
which occur west of Cape Jaffa. Despite the
productivity and biodiversity of the region, few
marine biological studies, particularly subtidal
research, have been undertaken in the region.
This is largely due to the very exposed and
inaccessible nature of the coast.
The intertidal assemblages on the rocky coastline of
the South East has been relatively well-described by
Womersley and Edmonds (1958).
Animals
dominate the littoral fringe, the upper eulittoral and
the mid-eulittoral zones, while plants dominate the
lower eulittoral and sublittoral zones. In the littoral
fringe blue green alga, lichen and small gastropods
may be found, whilst in the eulittoral zone, worms,
algae (eg. Hormosira banksii), and various species
of gastropod molluscs such as chitons and limpets
will be found. In the sublittoral zone the Bull Kelp
(Durvillaea potatorum) occurs east of Cape Jaffa, on
the outer edges of reefs subject to high wave energy.
In the deeper, protected rock pools, other species are
common such as algae (eg. Cystophora sp.,
Sargassum sp.), abalone (eg. Haliotis laevigata) and
various ascidians, asteroids, echinoids, anemones,
and crustaceans.
5.2
Subtidal Ecology
The whole south-east region of South Australia is
typified by both, low and high wave energies,
depending on the presence/absence of these
offshore reefs, which attenuate wave energy.
Exposed coastal areas, particularly from Cape
Buffon to Cape Banks, are typified by a high swell
(2-4m), high wave energy environment, which is
strongly erosional in nature and characterised by
conditions of strong surge and sand scour. Low
wave energies occur in the few coastal embayments
of Lacepede, Guichen, Rivoli Bays and Nora
Creina, due to attenuation by offshore reefs. The
offshore reef system is patchy in areas, and is
interspersed with areas of medium to coarse sand
(without seagrass).
Page 239
SOUTH-EAST COAST REGION
Due to the lack of depositional environments, soft
bottom
habitats
(colonised
by
seagrass
communities) are rare along the south-east coast
region of South Australia.
Seagrass habitats
(dominated by Posidonia australis, Amphibolus
antarctica and Heterozostera tasmanica are
present, but rare, being mainly confined to the
sheltered areas of southern Lacepede Bay (where
extensive meadows occur), northern Rivoli Bay,
Nora Creina, Guichen Bay and the sheltered interreefal areas west of Port MacDonnell. The dune
calcarenite bedrock characteristically forms low
platform reefs, with abundant crevices and
microhabitats
for
calcareous
organisms
(particularly coralline algae and bryozoans) and
sponges. As on Kangaroo Island, species of
Caulerpa (eg. C.obscura, C.cactoides, C.brownii)
appear to play a key role in colonising sediments
and consolidating sediments on low platform reefs.
Kelp forests (dominated by Macrocystis
angustifolia), dominate in exposed to moderately
areas areas (from Cape Jaffa eastwards), in the 1025 metre depth range - providing significant shelter
for inner reefs (ie. via reducing wave energy).
Kelp forests are generally absent from the Canunda
region (ie. from Cape Buffon to Cape Banks) due
to the general absence of reefs and high wave
energies.
Few detailed subtidal marine biological studies have
been conducted along the South East coast.
Shepherd (1979) recorded over 180 algal species
from Cape Northumberland, and recognised three
distinct algal communities, which are probably
characteristic of most of the lower South East
region:
1
a red algal community at 4-10m comprising
plants up to 0.1m high (ie. Chondria, Gelidium
glandulaefolium, Hymenena affinis, Laurencia
elata, L.filiformis, Melanthalia concinna,
M.obtusata and Phacelocarpus complanatus)
with only scattered plants of larger brown algae
(ie. Acrocarpia paniculata, Ecklonia radiata,
Carpoglossum confluens, Perithalia caudata)
and patches of Caulerpa flexilis.
2
an Ecklonia radiata/red algal community from
10m to 15-30m, with Ecklonia as the dominant
canopy species, with an understorey of red
algae (eg. Callophyllis lambertii, Melanthalia
obtusata, Nizymenia australis, Phacelocarpus
complanatus, P.labillardieri).
3
a deep water (30-38m to 61m), sparse red algal
community (ie. Lenormandia marginata,
Phacelocarpus
complanatus,
Pterocladia
lucida, Rhodophyllis multipartita and Ptilonia
australasica).
In shallow waters, down to 13m, major
macrofaunal reef species include grazing
molluscs, Subninella undulata and Haliotis
rubra (Blacklip Abalone), and the Southern
Rock Lobster (Jasus edwardsii), which is
typically found in crevices or caves, and feeds
on the sea urchins, Halopneustes porossima and
Amblypneustes sp. The Red Rock Crab and
Rough Rock Crab are found occasionally, as
well as the stalked ascidian, Pyura australis. At
deeper depths (from 13-15m), the molluscs,
Aplysia parvula, Anthochiton tricostalis,
Choriplax pattisoni and Paricoplax crocina and
the isopods, Cilicaea curtispina and Synischia
sp, the Weed Crab, Naxia tumida, and the
echinoderm,
Aporometra
wilsoni,
are
commonly found (Shepherd 1979).
5.3
Fish
The coastal and adjacent offshore fish fauna of the
South East is significant because of its considerable
commercial importance. However, the lesser-known
inland fish fauna is also significant in this region
because it occupies the most westerly part of
Australia's South East Coast Drainage Division.
The inland waters in the Coorong range in salinity
from fresh through brackish to very saline. They
can, therefore, be selectively occupied by marine
fishes, as well as species which tolerate intermediate
ranges of salinity. At least twenty four marine and
freshwater species have been recorded from the
inland waters of the Coorong (Glover 1983). Of
these, five are known to regularly move between the
sea and fresh or brackish estuarine waters to breed.
A further four species are essentially marine forms
which regularly enter brackish estuarine and fresh
inland waters, as well as inland saline waters. Other
marine fishes recorded in inland waters include
several marine fishes such as Shark and Ray,
Flounder, Sea Bream, Trevally, King George
Whiting and Australian Salmon/Salmon Trout.
Species that live in both the sea and fresh or brackish
water at some stage during their life cycle include:
−
−
−
−
−
−
Short Headed Lamprey (Mordacia mordax)
Wide Mouthed Lamprey (Geotria australis)
Short Finned Eel (Anguila australis)
Common Galaxias (Galaxias maculatus)
Sea Mullet (Mugil cephalus)
Yellow Eye Mullet (Aldrichetta forsteri)
Page 240
SOUTH-EAST COAST REGION
Small Mouthed Hardyhead (Atherinosoma
microstoma)
Marine Hardyhead (Pranesus ogilbyi)
Mulloway (Argyrosomus hololepidotus)
Black Bream (Acanthopagrus butcheri)
Congolli (Pseudaphritis urvillii)
Along rocky shores in the cooler areas, the marine
flora is dominated by spectacular forests of kelp
(Macrocystis angustifolia) in the deeper waters, and
in the upper subtidal, by a zone dominated by the
giant, Bull Kelp (Durvillea potatorum).
Of particular significance in the lower South East is
the Australian Grayling (Prototroctes maraena),
which is one of Australia's rarest and most
extinction-threatened fishes. This species probably
spends part of its life in the sea. In the lower South
East it has only been recorded in Ewens Ponds and
Picanannie Ponds (Glover 1983, Thurgate 1992).
The coastal waters off the South East are among
some of the most productive waters along the whole
of the southern Australian coastline. This is
primarily a result of the presence of nutrient-rich
upwellings. As such, this region is significant for a
number of commercially important species,
including the Southern Rock Lobster, Abalone and
the Goolwa Cockle.
−
−
−
−
−
5.4
Seabirds
Bird life is prolific along the South East coast,
particularly along the Younghusband Peninsula, due
mainly to the estuarine conditions of the Coorong.
The Murray Mouth is an area rich in fish and bird
species such as the Cape Barren Goose (Cereopsis
novaehollandiae), Plovers (Vanellus sp. and
Pluvialis sp.) and Dotterels (Charadrius sp.). Rare
or endangered bird species that might nest in the
sand dunes of the Coorong region include the
Rufous Bristlebird (Dasyornis broadbenti), and the
Orange-bellied Parrot (Neophema chrysogaster).
5.5
Marine Mammals
Cetaceans have also been found washed up on the
beach and include notable specimens of a Pigmy
Right Whale (Caperea marginata), a Pigmy Sperm
Whale (Kogia breviceps), a Sperm Whale (Physeter
macrocephalus) and a Minke Whale (Balaenoptera
acutorostrata).
MARINE CONSERVATION VALUES
1
1.1
Commercially Exploited Species
SIGNIFICANT
BIOLOGICAL
PHYSICAL FEATURES
AND
The Coorong
The Coorong is a unique coastal landform with a
shallow backwater estuary and ephemeral salt lake
system that drains gradually into the sea behind a
semi-consolidated sand barrier, the Younghusband
Peninsula. The Coorong lagoons are an important
feeding, breeding, spawning and nursery area for
fish as well as supporting one of the largest
concentrations of migratory waders in Australia.
The ocean beach adjacent to the Coorong National
Park and Game Reserve is an important nesting area
for the Australian endemic Hooded Plover
(Charadrius rubricollis) and some 27 other species
of seabirds and waders have been recorded here.
The marine biota of this area has received little
attention, although the Coorong Lagoon area on the
landward side is relatively well documented. On the
high wave energy beaches of Younghusband
Peninsula, it is likely there exists a paucity of
species, with small invertebrates such as amphipods
and isopods being most common. Known bivalve
species include the commercially important Goolwa
Cockle (Plebidonax deltoides). Fish species such as
Mulloway (Argyrosomus hololepidotus) are thought
to spawn in this area, with the juveniles subsequently
moving into the lagoon nurseries.
Biological
Rich Diversity of Macroalgae (Seaweeds)
The lower South East as a region contains one of the
richest floras of marine macroalgae or seaweeds in
the world. This is primarily due to the fact that this
region is transitional, spanning both, the eastern
cold-water Maugean biogeographical region (east of
Robe) and the western, warmer element of the
Flindersian (west of Robe).
Coastal Wetlands of National Importance
A Directory of Important Wetlands in Australia
(ANCA 1996) list the following coastal wetlands of
national importance along the South East coast:
1.
The Coorong, Lake Alexandrina and Lake
Albert
2.
Butchers and Salt Lakes
3.
South East Coastal Salt Lakes (Lake Robe,
Lake Eliza, Lake St Clair, Lake George)
Page 241
SOUTH-EAST COAST REGION
4.
Ewens Ponds
5.
Piccaninnie Ponds
The variable coastal scenery of the South East is
generally considered to be spectacular.
"Geological Monuments"
Southern Right Whale (Eubalaena australis)
The endangered Southern Right Whale (Eubalaena
australis) is often sighted each year along the South
East coast in the winter months, from May-June.
This region is probably part of the migratory path of
whales which tend to move from the cooler waters
of Tasmania, via Encounter Bay and Kangaroo
Island, to the warmer waters of the Head of the
Great Australian Bight, where they give birth and
nurse their young (J.Ling, SA Museum, pers.comm).
1.2
Physical
Coastal Upwellings
The coastal upwellings of the South East are a
highly significant physical and ecological process.
The upwellings along this region represent the most
significant coastal upwellings to be found along the
whole of the Southern Australian coastline, and are
due, in part, to the meterological conditions of the
region. As a major source of nutrients to coastal
ecosystems, they provide the essential basis for
much of the region's highly productive coastal
fisheries. Three centres of upwelling have been
identified in the South East region: Robe, Southend
and Port MacDonnell (Lewis 1981).
Geology
The geology of the South East coast is of immense
significance both nationally and internationally.
Indeed, "it must be concluded that the whole of the
South East coast is of immense geological
significance, not only for reasons of uniqueness but
also because most of the features are not localised
but cover extensive areas. The South East of South
Australia is the only known area in the world which
has preserved a complete record of late Pleistocene
sea-level changes as stranded sand dune ridges.
Thus, the South East coast holds the key to the
geological and geomorphological history of the
Pleistocene, which is of concern to geologists and
geomorphologists studying this time period during
which a large part of the present landscape was
moulded."54
There are 15 areas of geological significance in the
South East region which are associated with the
coastline or offshore waters.
These areas have been identified and recognised as
"geological monuments" by the South Australian
Museum and the Geological Society of Australia,
and include the following sites:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
The Coorong (carbonate lakes)
Taratap Rocks
Guichen Bay Conservation Park (including
Cape Thomas)
Baudin Rocks Conservation Park (Godfrey
Islands)
Cape Dombey (coastal features, e.g. blowhole,
arch in aeolianite)
Little Dip Conservation Park
Beachport Conservation Park, Cape Martin,
Cowrie and Penguin Island
Canunda National Park and Cape Buffon
Carpenters Rocks to Cape Banks, including
Admella Dunes
Blackfellows Caves
Nene Valley (dune area)
Douglas Point
Middle Point
Cape Northumberland
Stony Point (Flint Point)
Further details of these areas are supplied in the
relevant regional biounit descriptions below.
2
SIGNIFICANT
CULTURAL
HISTORICAL FEATURES
AND
The following description of Aboriginal and
European history along the South East coast is
necessarily brief and selective. The aim is to give
the region a historical perspective with emphasis on
coastal and maritime history. Only details of
Aboriginal historical and cultural sites that have
been published in the available literature are
described. Aboriginal sites, objects and remains
are protected under the South Australian
Aboriginal Heritage Act (1988), and a register of
such sites, objects and remains is kept with the
Aboriginal Heritage Branch of the South Australian
Department of Environment, Heritage and
Aboriginal Affairs.
54
From South East Coast Protection District Study Report (UEPG
1982).
Page 242
SOUTH-EAST COAST REGION
2.1
Aboriginal
The Aboriginal history of the South East is highly
complex and difficult to summarise easily. At the
time of European settlement, however, there were
three known tribes occupying land along the coast:
1
Tanganekald, who lived in the Coorong region,
from the Murray Mouth to the Granites;
2
Meintangk, who lived along the coast from the
Granites to Cape Jaffa and inland;
3
and the Buandik, who lived from Cape Jaffa to
the Glenelg River (Victoria) and inland
The South East and its coast is an extremely
important Aboriginal heritage area. Remnants of
Aboriginal activities such as middens occur all along
the coast, and many of these, "provide a unique
record of the events of the last 10,000 years and as
such are of considerable scientific and heritage
significance. Indeed it has been claimed that the
diversity and preservation of many of these sites
make them of national, if not international,
importance."55
2.2
3
CURRENT
CONSERVATION
STATUS OF THE SOUTH EAST COAST
The South East Province is the most underrepresented in terms of Marine Protected Areas (or
MPAs) of all the coastal provinces in South
Australia. As such, no Aquatic Reserves or large,
multiple use Marine Parks have been declared in this
region. The majority of MPAs in this region
comprise `netting closures', many of which have
generally not been formally recognised as MPAs
(see Ivanovici 1985, McNeill 1991). However, this
coast does contain three of the four Marine
Sanctuaries which have declared in South Australia.
All of these sanctuaries were established for the
protection of a single species, the Southern Rock
Lobster.
Present MPAs in this region include:
−
Marine Reserves
None
−
Marine Park
None
−
−
−
Marine Sanctuaries
Cape Jaffa (950 ha)
Margaret Brock Reef (314 ha)
Penguin Island and Rivoli Bay (40 ha)
−
−
−
−
−
−
−
−
−
−
Netting Closures
Murray Mouth
Goolwa
Guichen Bay (Robe)
Robe Lakes
Lake George
Rivoli Bay
Beachport – Salmon Hole
Admella Dunes
Port MacDonnell
Brown Bay
European
Early Discoverers
The South East coast was the first part of South
Australia to be sighted by British subjects in 1800.
Lieutenant James Grant, aboard the "Lady Nelson",
viewed the coast and named Mt. Gambier, Mt.
Shank, Cape Northumberland and Cape Banks. The
process of exploring and settling the coast began in
1839. Robe was declared in 1847 and became the
first port to facilitate safe shipping and the export of
wool.
Shipwrecks
Some 46 shipwrecks occurred along the South East
coast between 1844 and 1960. The most notable
include the `Varoo’ at Cape Northumberland in
1856, the `Admella’ at Carpenter Rocks in 1859; the
`Tenterden’ at Cape Northumberland in 1893 and
the `Maria’ at Cape Jaffa in 1840. Wrecks in
excess of 75 years old in Commonwealth waters are
automatically
protected
by
Commonwealth
legislation, ie. Historic Shipwrecks Act 1976. Other
wrecks may be protected if of significant value.
Wrecks situated in State waters may be protected by
proclamation under the State legislation, ie. Historic
Shipwrecks Act 1981.
55
From South East Coast Protection District Study Report (UEPG
1982).
Page 243
SOUTH-EAST COAST REGION – COORONG BIOUNIT
XXVII MARINE BIOGEOGRAPHY AND CONSERVATION VALUES OF THE
COORONG BIOUNIT
The Coorong Biounit extends from Encounter Bay (near Middleton) to Lacepede Bay (Cape Jaffa) and includes the
estuarine Coorong Lagoons located in the Coorong National Park. However, emphasis here is placed on the
marine aspects of the lagoons and their connection with the Southern Ocean side of the Younghusband Peninsula.
The biounit represents a total area of 1,290,715 ha. and a coastal distance of approximately 190 km. It faces in a
southwesterly direction into the Southern Ocean.
MARINE BIOGEOGRAPHY
1
OCEANOGRAPHY
The gently curving sandy coast running from the
Murray Mouth to Cape Jaffa represents a classic
example of spatial variation in nearshore wave
energy and beach surfzone morphology controlling
the evolution, extent and nature of the entire coastal
zone. Two factors are paramount in this evolution of
this coast; (i) the gradient of the nearshore and (ii)
the breaker wave energy. For the first 100km, the
offshore gradient is 1:260, and then declines
gradually. As a result the zone of significant
deepwater wave attenuation widens from 5 to 38 km,
causing wave power to decrease beyond 100km to
the degree that it is nonexistent between 168 and
190km, the waves having lost all their energy
crossing the low gradient nearshore zone.
The longshore variation in breaker wave power has
produced four zones within the Younghusband
Subprovince:
1
2
3
4
Coorong I (0 to 100m from the Murray Mouth)
characterised by high wave power.
Coorong II (100m to 145km) characterised by
moderate energy transition zone.
Coorong III (145km-168km) a low energy
transition zone (waves are the dominating force
in all zones).
Lacepede Bay (168km-190km) - zero breaker
power has resulted in nearshore currents and
locally generated wind waves being the
dominating components of marine energy
(Short & Hesp 1980).
2
GEOLOGY
AND
GEOMORPHOLOGY56
COASTAL
The Coorong Biounit is dominated by sandy beach
dunes, beach ridges and blowouts. Of particular
geological note are the `Granites', north of
Kingston, which are an unusual outcrop of coarse
granite on a sandy beach. As the only visible
evidence of Paleozoic bedrock along the entire
South East coast, they are of considerable
geological significance.
The beach ridge plains of Lacepede Bay are also of
considerable
geomorpholgical
significance,
providing evidence of shoreline progradation over
the past 500 to 7,000 years.
The Murray River empties into the sea via a narrow
but shifting mouth between the high dunes of Sir
Richard and Younghusband Peninsulas. Holocene
dune complexes extend from the mouth to
Lacepede Bay.
The largest and most well-known coastal landform
along this biounit is the Coorong. The Coorong is
a unique coastal landform with a shallow
backwater estuary and ephemeral salt lake system
that drains gradually into the sea behind the
Younghusband Peninsula. Averaging about 1.2 km
wide and over 145 km long, the Coorong is
composed of a basal Pleistocene calcrete unit and
an overlying dune sheet associated with the
Holocene Marine transgression. The presence of
water in the interdunal depression in the southern
section is seasonal and the lagoon is replaced by a
series of ephemeral lakes and swampy mud flats.
56
From South East Coast Protection District Study Report (UEPG
1982).
Page 244
SOUTH-EAST COAST REGION – COORONG BIOUNIT
3
Inside the reefs, under moderate wave
conditions, species such as Cystophora retorta,
C.monoliformis, and Sargassum sonderi also
occur. Margaret Brock Reef is the most
westerly extent of the range of Macrocystis
angustifolia and Durvillea potatorum along the
southern temperate coastline of Australia.
BIOLOGY
Major Inshore Habitats
−
Major intertidal habitats in the region include
sandy beaches, and some sections of rocky
shore in the southern section of the biounit.
−
Of the total inshore subtidal habitats mapped
in the biounit (170,935 ha), sandy bottoms
comprise 75,497 ha (44.2%), reefs comprise
70,376 ha (41.2%), and seagrass meadows
comprise 25,062 ha (14.7%).
•
−
Major Benthic Communities
•
−
Macroalgal
Offshore rocky areas in this region, essentially
consist of a series of parallel rocky reefs,
which stretch offshore from the Coorong
(from Encounter Bay to Cape Jaffa) from 11
metres (and deep offshore) on the broad
continental shelf known as the Lacepede
Shelf. These parallel reefs are submerged
beach ridge systems, consisting of Pleistocene
dune calcarenite, and form low profile reefs,
subject to sand scour. At depths of 20m and
deeper (down to 50-60 m), these low profile
reefs are dominated by a sparse mixed red
algal assemblage and bryozoans. At shallower
depths and in areas of high wave energy, these
reefs are dominated by Cystophora
platylobium, and to a lesser extent,
Seirococcus axillaris, Ecklonia radiata, and
Carpoglossum confluens, with a mixed red
algal understorey (eg. Areschougia congesta,
Dictymenia tridens) and encrusting coralline
algae (eg. Metagoniolithon). These high wave
energy reefs are generally low in species of
molluscs, crustaceans, and fish. In areas of
moderate wave exposure (in southern
Lacepede Bay, south of the Granites), these
reefs are dominated by the fucoids, Scaberia
agardhii, Cystophora retorta, and Cystophora
gracilis and the red algal, Osmundaria
prolifera. Margaret Brock Reef and North
Reef (west of Cape Jaffa) comprises a series
of low profile, limestone (ie. dune calcarenite)
reefs, dominated by fucoids (such as
Cystophora platylobium, and to a lesser
extent, Perithalia caudata, Carpoglossum
confluens, Seirococcus axillaris, Scytothalia
dorycarpa, Ecklonia radiata), and a mixed red
algal assemblage (eg. Sonderpelta coriacea),
with Giant Kelp (Macrocystis angustifoliadominated) communities on the outer, more
exposed parts of the reef system.
Seagrasses
Seagrass beds are absent along most of the
offshore and nearshore coast off the Coorong,
until south of the Granites. High wave energy
and active sand movement probably prevent
the colonisation of the sandy areas north of
this area. Seagrass in the Coorong-Cape Jaffa
region is principally located in nearshore
region of southern Lacepede Bay, extending
north along the coast to the Granites. Dense
meadows of Posidonia australis (particularly
in shallow waters), Amphibolus antarctica and
Posidonia angustifolia occur in the bay from
0.5-12 metres. Patches of Posidonia coriacea
and Heterozostera tasmanica also occur.
Rivers and Estuaries
−
The Coorong.
−
River Murray.
Coastal and Offshore Islands (or Reefs)
−
Offshore parallel reefs occur throughout the
biounit.
MARINE CONSERVATION VALUES
1
1.1
SIGNIFICANT
BIOLOGICAL
PHYSICAL FEATURES
AND
Biological
Coastal and Marine Wetlands of National and
International Importance
−
The Coorong lagoons and Lakes Albert and
Alexandrina have been identified as wetlands
of national importance (see ANCA 1996) and
have also been proclaimed as a Wetland of
International Importance under the Ramsar
Convention.
Page 245
SOUTH-EAST COAST REGION – COORONG BIOUNIT
The Coorong National Park, Carbonate Lakes,
Finniss River/Currency Creek mouths area,
Mud Islands Game Reserve, Mundoo Island
and
surrounding
area,
Salt
Lagoon
Conservation Park, Tolderol and Mosquito
Points and Tolderol Game Reserves are listed
on the Register of the National Estate. The
area has also been identified as an area of
international importance for shorebirds by
Watkins (1993).
−
The Coorong is a shallow, saline to
hypersaline, coastal lagoon system more than
100 km in length and separated from the
Southern Ocean by a narrow sand dune
peninsula known as the Younghusband
Peninsula. The Coorong is connected to the
sea via a narrow channel at the mouth of the
Murray River (which is the principal source of
freshwater for the Coorong). The Coorong
Lagoon waters support a range of aquatic
plants and animals and are an important
feeding, breeding, spawning and nursery area
for key commercial fish species as well as
supporting one of the largest concentrations of
waterbirds and migratory waders in Australia.
The Coorong supports important nesting
colonies of cormorants, herons, egrets, ibises
and terns. Mosquito and Tolderol Points
support a high diversity of waterbirds and are
one of the best localities in the State for
waders and terns. The Coorong lagoons are
very important areas for migratory waders,
and provide a drought refuge when central or
eastern Australian wetlands dry out (ANCA
1996). The area is one of the ten major areas
for large concentrations of waders in
Australia, and one of the few south of the
Tropic of Capricorn (ANCA 1996). During
drought years, up to a quarter of a million
migratory waders may be present during
summer. In 1981, the Australasian Wader
Study Group estimated the summer population
of waders for the Coorong at 122 000,
compared with a South Australian population
of 200 000 and an Australian population of
403 000. The Coorong is a major migration
stopover for shorebirds, with over 21 species
recorded in the area. The ocean beach and
foredunes adjacent to the Coorong National
Park and Game Reserve is an important
nesting area for the Australian endemic
Hooded Plover (Charadrius rubricollis) and
some 27 other species of seabirds and waders
have been recorded here.
Threatened species of waterbirds recorded in
the area include the Orange-bellied Parrot,
Neophema chrysogaster (Ne, Se), Little Tern,
Sterna albifrons (Ne, Sv), Hooded Plover,
Thinornis rubricollis (Nv, Sv) White-bellied
Sea-Eagle, Haliaeetus leucogaster (Sv), Cape
Barren Goose, Cereopsis novaehollandiae (Sv),
Little
Egret,
Egretta
garzetta
(Sv),
Australasian Bittern, Botaurus poiciloptilus
(Sv), Musk Duck, Biziura lobata (Sv), Painted
Snipe, Rostratula benghalensis (Sv), Latham’s
Snipe, Gallinago hardwickii (Sv), Eastern
Curlew, Numenius madagascariensis (Sv),
Fairy Tern, Sterna nereis (Sv), Australasian
Shoveler, Anas rhynchotis (Sr), Baillon’s
Crake Porzana pusilla (Sr) and Spotless Crake
P.tabuensis (Sr). A total of 90 species of
waterbird have been recorded in the area: 33
are listed under treaties.
Many species of
waterbirds breed in the area, including the
largest breeding colony of Pelicans, Pelecanus
conspicillatus, in the world (and the only area
in South Australia where Pelicans breed
annually).
The lagoons itself contains
important breeding sites for Crested Tern
Sterna bergii, Fairy Tern and Chestnut Teal,
Anas castanea.
A total of 24 species of
marine and freshwater fish have been recorded
from the inland waters of the Coorong,
including
the
following
economically
important species, Mulloway, Argyrosomus
hololepidotus, Yellow-Eye Mullet, Aldrichetta
fosteri, Greenback Flounder, Rhombosolea
tapirina, Australian Salmon Arripis truttacea,
and Black Bream, Acanthopagrus butcheri.
Other commercially important species in the
area include the Goolwa Cockle, Plebidonax
deltoides, which provides the major source of
cockles for bait in south east Australia.
−
The Coorong National Park and Game
Reserve itself is an important area as it
contains a representative sample of coastal and
salt-influenced terrestrial habitats as well as an
unusual set of aquatic habitats in the Coorong
Lagoon and ephemeral lakes, which are an
important
ecological
(and
aesthetic)
component of the region. The empheral salt
lakes are highly productive ecosystems and
are of unusual geological and biological
significance, and are actively forming unique
associations of carbonate minerals and
dolomite muds.
The hydrology of the
Coorong Lagoons is determined by a complex
interaction of water from a number of sources
including sea water, the River Murray, rainfall
and groundwater.
Page 246
SOUTH-EAST COAST REGION – COORONG BIOUNIT
Lloyd & Balla (1986) considered this area to
be of outstanding environmental value and
recommended that it be given status as a
wetland reserve. The Coorong National Park
and Game Reserve are on the Register of the
National Estate.
−
Butchers Lake and adjacent salt lakes have
been identified as wetlands of national
importance (see ANCA 1996). The area
comprises three shallow lakes on the inland
side of coastal dunes in Lacepede Bay,
approximately 7km south west of the township
of Kingston. The three lakes act an a
important refuge for waterbirds in summer or
during drought and is one of the few known
habitats of the nationally endangered Orangebellied Parrot, Neophema chrysogaster (Ne,
Se) (ANCA 1996). The area also contains
some of the last remaining significant stands
of coastal vegetation between the Coorong
Lagoon and the township of Robe. A total of
16 species of waterbird have been recorded in
the area: 3 are listed under treaties. The area
is conserved within the Butchers Gap
Conservation Park, which is listed on the
Register of the National Estate.
Other Areas of Recognised Conservation
Significance
−
Lacepede Bay. This bay contains extensive
beds or meadows of seagrasses such as
Posidonia australis, Amphibolis antarctica
and Heterozostera tasmanica, which are
ecologically important as nursery and feeding
areas particularly for species of fish and
crustacea. Leafy Sea Dragons, Phycodurus
eques, have been recorded on offshore reefs
off the Kingston jetty (B.Lowry pers.comm.).
In this region, the economically important
Southern Rock Lobster (Jasus edwardsii) also
forages in these seagrasses. Lacepede Bay was
recommended as a scientific reserve by the
Southeast Coast Protection Board (1982).
−
Cape Jaffa is located on the southern
headland of Lacepede Bay and is a designated
Marine Sanctuary for Southern Rock Lobsters
(CONCOM workshop designation as a Marine
Reserve). The reserve was declared in 1971
and proposed by the rock lobster fishing
industry. Removal of juvenile Southern Rock
Lobster is prohibited within 1 km of the High
Water Mark of the defined area. The area is
also a popular diving location and is listed in
`Dive South Australia: The Best Dive Sites in
South Australia’ (Diving Industry Association
of South Australia).
−
Margaret Brock Reef is located west of Cape
Jaffa and is a designated Marine Sanctuary for
Southern
Rock
Lobsters
(CONCOM
workshop designation as a Marine Reserve).
The reserve was declared in 1971 and
proposed by the former SA Department of
Fisheries. Removal of Southern Rock Lobster
is prohibited within 1 km of the lighthouse on
Margaret Brock Reef. The area is also a
popular diving location and is listed in `Dive
South Australia: The Best Dive Sites in South
Australia’ (Diving Industry Association of
South Australia).
−
The Pinnacles. Cape Jaffa is protected by a
reef running in a line from the point south of
the jetty, seaward for a distance of 5-6kms, to
the old lighthouse platform on Margaret Brock
reef. The reef is recognised locally for its
bommies and an abundant range of marine
life, including prolific fish life (such as
schools of Banded Sweep, Silver Drummer,
Leather Jackets, Cale Fish, Parrot Fish,
Wrasses and also, sightings of Leafy Sea
Dragons). The area is also a popular diving
location and is listed in `Dive South Australia:
The Best Dive Sites in South Australia’ (Diving
Industry Association of South Australia).
−
The endangered Southern Right Whale
(Eubalaena australis) is often sighted each
year along this region of coast from May-June.
This region is probably part of the migratory
path of whales which tend to move from the
cooler waters of Tasmania, to the warmer
waters of the Head of the Great Australian
Bight, where they give birth and nurse their
young (J.Ling, SA Museum, pers.comm.).
Page 247
SOUTH-EAST COAST REGION – COORONG BIOUNIT
1.2
Physical
−
The `Granites' north of Kingston, is the only
visible evidence of Paleozoic bedrock along
the entire south-east coast.
−
Beach ridge plains of Lacepede Bay are
evidence of shoreline progradation over the
past 500 to 7000 years and are of considerable
geomorphological significance (i)
−
The Murray River empties into the sea via a
narrow but shifting mouth between the high
dunes of Sir Richard and Younghusband
Peninsulas.
Geological Monuments
−
Coorong: carbonate lakes.
−
Taratap Rocks: adamellite outcrop with
diverse textures. The quarry is on Crown
Land and there is an outcrop on the beach to
the northwest.
2
2.1
OTHER VALUES
Commercial Fisheries
The main single species fishery in this region is the
Southern Rock Lobster (Jasus edwardsii) industry.
Together Cape Jaffa and Kingston have the third
largest concentration of Southern Rock Lobster
fishing boats in the South East, representing
approximately 20% of the total number of boats for
the Southern Zone.
Southern Rock Lobster
This biounit encompasses 2 fishing zones: the
offshore waters of the Coorong (Fishing Zone 50)
and the nearshore waters of the Coorong (Fishing
Zone 51). In 1995/96 and 1996/97 a total of 16 and
13 licensed operators fished in the offshore waters
of the Coorong Biounit (ie. Fishing Zone 50),
catching approximately 43,529 and 31,894 kg of
lobsters, respectively (or 0.85% and 0.62% of the
total catch for Southern Rock Lobster in South
Australian waters). In contrast, in the nearshore
waters there is at least twice as much production.
In 1995/96 and 1996/97 a total of 19 and 16
licensed operators fished in the nearshore waters of
the Coorong (ie. Fishing Zone 51), catching
approximately 94,490 and 91,905 kg of lobsters,
respectively (or 1.85% and 1.80% of the total catch
for Southern Rock Lobster in South Australian
waters).
Abalone
Negligible Blacklip Abalone and Greenlip Abalone
is presently commercially harvested within the
Coorong Biounit, apart from the southern waters
near Cape Jaffa (see Canunda Biounit).
Marine Scalefish Fisheries
The Coorong Biounit principally encompasses 2
fishing zones: Fishing Zones 50 and 51. During
1995/96 and 1996/97, 24 commercial licence
holders (made up of Marine Scalefish and
Restricted Marine Scalefish licence categories)
caught commercial marine scalefish species from
the inshore Coorong waters of this biounit (ie.
Fishing Zone 51). License holders expended
approximately 836 and 829 boat days effort fishing
these waters during 1995/96 and 1996/97,
respectively. The marine scalefish catch for this
region (ie. Fishing Zone 51) represented 129,998
kg in 1995/96 and 142979 kg in 1996/97(or 1.25%
and 1.41% of the total catch for the marine
scalefish fishery in South Australian waters).
In the offshore Coorong waters of this biounit (ie.
Fishing Zone 50), a total of 17 and 13 licensed
operators fished 559 and 448 days in this region in
1995/96 and 1996/97, catching approximately
238,182 and 144,414 kg, respectively (or 2.29%
and 1.42% of the total catch for the marine
scalefish fishery in South Australian waters).
A well established fishery along the Coorong Beach
is the removal of the Goolwa Cockle (Plebidonax
deltoides) (400 tonnes/year).
Commercial netting for Mulloway (Argyrosomus
hololepidotus) and Shark also occurs along the
Coorong beach.
Around Kingston and the Granites, a small amount
of Australian Salmon (Arripis trutta esper) trolling
occurs, mainly to provide bait for lobster (5
tonnes/year).
Shark and Abalone (Haliotis rubra and H.laevigata)
are also taken from the waters of the South East
coast.
Although license holders are not restricted to fishing
in this biounit, the following licenses are registered
in this area:
Kingston: 21 Southern Rock Lobster licenses, 1
unrestricted marine scalefish license.
Page 248
SOUTH-EAST COAST REGION – COORONG BIOUNIT
2.2
Aquaculture
A research and development site has been approved
for trialing salmon aquaculture in this region near
Cape Jaffa and another site has been sought near
Robe. Additional interest has been expressed in
undertaking trials for kelp culture in Lacepede Bay
and around Cape Jaffa. No other marine-based
aquaculture interests current exists in this region.
The South East Aquaculture Management Plan
(Gilliland 1996) proposes limited aquaculture
development in this region:
Coorong Policy Area
−
Coorong Zone (ie. waters adjacent to the
Coorong National Park, to the Murray Mouth)
– licenses will not be considered within this
zone.
Kingston Policy Area
−
Cape Jaffa Aquaculture Zone (ie. inshore
Cape Jaffa) – licenses will be considered for a
maximum of 40 ha of aquaculture in this zone.
Industry identified this area as being suitable
for aquaculture, especially finfish culture.
−
Kingston Exclusion Zone (ie. inshore waters
adjacent to Butchers Gap and Bernouilli
Conservation Parks, Granites) – licenses will
not be considered for aquaculture in this zone.
−
Kingston Zone (ie. remaining waters in
Lacepede Bay, from north of the Granites to
Cape Jaffa) – licenses will not be considered
for aquaculture greater than 60 ha, or for
intertidal oyster culture or within 250m of the
Cape Jaffa jetty.
2.3
−
Tourism
−
Kingston: sailing, boating, diving, swimming,
jetty fishing, historic area.
−
Kings Camp: swimming,
fishing, scenic area.
−
Younghusband Peninsula: whale watching,
Coorong National Park (beach fishing,
camping, bird watching, off-road vehicles),
Murray Mouth.
−
Lacepede Bay: Butchers Gap Conservation
Park, camping, fishing, scenic area.
−
SCUBA diving: Margaret Brock Reef and
North Reef, near Cape Jaffa, are popular dive
spots in the region and are listed in `Dive
South Australia: The Best Dive Sites in South
Australia’ (Diving Industry Association of
South Australia). North Reef is a 4-5km reef
which runs parallel to shore starting from
Margaret Rock, towards Kingston.
The
whole reef is characterised by bommies and
abundant marine life, including Southern Rock
Lobster.
2.4
−
Recreation and Tourism
Fishing
−
−
Coorong and Murray Mouth: boat and shore
fishing. Major species: Black Bream, Sand
Flathead, Yelloweye Mullet, Australian
Salmon, Mulloway and Flounder. Fishing in
this area is centred mainly around the Murray
Mouth.
Kingston and The Granites: boat, beach and
jetty fishing. Major species: King George
Whiting, Sand Flathead, Yelloweye Mullet,
Australian Salmon, Snapper, Mulloway,
Snook,Garfish, Southern Rock Lobster,
Tommy Rough and Trevally.
Cape Jaffa: beach, rock, boat and jetty fishing.
Major species: King George Whiting, Sand
Flathead, Yelloweye Mullet, Australian
Salmon, Snapper, Mulloway, Snook, Garfish,
Tommy Rough, Trevally, Toothbrush
Leatherjacket and Silver Drummer.
2.5
boating,
jetty
Scientific Research and Education
Fisheries research in this area includes, regular
catch and effort monitoring of the major
commercial fisheries in the region, both
marine (Southern Rock Lobster, Abalone and
marine scalefish) and inland waters; and
regular research and monitoring of fish stocks
of Southern Rock Lobster .
Adjacent Land Use
National and Conservation Parks
−
Coorong National Park (46,745 ha) (SANPWS
1988).
−
Butcher Gap Conservation Park, Lacapede
Bay (178 ha).
−
Bernouilli Conservation Park (near Cape
Jaffa) (242 ha).
Page 249
SOUTH-EAST COAST REGION – COORONG BIOUNIT
Agriculture/Industry
Shipwrecks
Major industries along the coast involve fishing and
fish processing. There are also some brown coal
deposits near Kingston that may become in demand
in the future.
Four wrecks are known to be located in the region
and are protected under the Commonwealth
legislation (ie. Historic Shipwrecks Act 1976).
These include:
Most adjacent land is used for livestock grazing and
cereal growing.
−
`Margit’: lost in 1911 is located offshore from
the Coorong National Park.
Drain outlets at Blackford (north of Kingston),
Maria Creek at Kingston (possibly impacting on the
seagrass meadows) and at Butchers Gap (south of
Kingston).
−
`Margaret Brock’: a three-masted wooden
barque built at Hobart Town inn 1848, and
wrecked on the Margaret Brock reef in 1852
whilst on its way to Melbourne from Port
Adelaide. The remains are located in 2-10
metres of water on the Margaret Brock Reef.
A bell from the ship has been recovered.
−
`Fanny’: a brig that ran ashore along the
Coorong Ninety Mile Beach in 1838 during a
gale. Her captain's favourable description of
the Coorong and members of the Ngarrindjeri
who helped him to safety was one of the first
to be reported in the early days of the colony.
−
`Maria’: wrecked at Lacepede Bay in 1840.
This wreck had profound effects on race
relations in the colony: the surviving
Europeans were killed apparently in
retribution for interfering with some of the
Milmenrura women and some of the guilty
persons were later executed under instruction
by Governor Gawler.
This dramatically
illustrated to the Milmenrura their lack of
power when dealing with the Europeans fire
power, and the eventual invasion of their
country seemed inevitable.
The dunes
opposite Dodds Landing is the burial site of
the survivors of the shipwreck and of those
hanged in retribution for their killing.
−
Additionally there are 11 other wrecks that are
believed to be located in this area, many of
which are of significant historical value and
are also protected under Commonwealth
legislation: `Maria’ (lost in 1840), `St
Vincent’ (lost in 1844), `Sophia Jane’ (lost in
1844), `Mariner’ (lost in 1845), `Victoria’
(lost in 1846), Gazelle’ (lost in 1848),
`Mozambique’ (lost in 1854), `Halcyon’ (lost
in 1857), `Agnes’ (lost in 1876), `Kingston’
(lost in 1895), and the `Elsie’ (lost in 1901).
Urban Centres
−
Kingston (population 1,367).
2.6
Features
Significant Cultural and Historical
Aboriginal
Aboriginal occupation of the Coorong area was
based on a rich and complex marine economy which
had evolved above a period of 8000 years. The
Coorong was the territory of a single tribe of the
Ngarrindjeri people, called the Tanganekald. A
large number of shell middens and mounds, cooking
ovens, campsite and cemeteries are found both near
the ocean beach and along the lagoon shoreline in
the Coorong. Other significant sites are the places
where crossings across the Lagoon occurred. These
crossings formed a vital communications link to the
`mainland' for each clan of the Peninsula and as
such, the importance of this area cannot be
overstated. The physical remains of the highly
cohesive and viable Aboriginal settlement of the
Coorong is recognised as one of the most
outstanding records of coastal adaptation in
temperate Australia and as such are considered of
international as well as national significance
(Coorong National Park and Game Reserve
Management Plan).
European
The Coorong region was a major section of the
overland stock route, mail coach route, migrant route
and the telegraph line route between Melbourne and
Adelaide. As such, it is an area of significant
historical and cultural value at a state level.
Page 250
SOUTH-EAST COAST REGION – COORONG BIOUNIT
3
−
−
−
−
−
Marine Reserves
None (although, the Coorong Lagoons are
within the boundaries of the Coorong National
Park)
Marine Parks
None
Marine Sanctuaries
Cape Jaffa (950ha), southern headland of
Lacepede Bay (removal of Southern Rock
Lobster is prohibited within 1 km of the High
Water Mark of the defined area)
Margaret Brock Reef (314ha), west of Cape
Jaffa (removal of Southern Rock Lobster is
prohibited within 1 km of the lighthouse on
Margaret Brock Reef).
Lacepede Bay-Cape Jaffa-Margaret Brock
Reef 58 59
−
Netting Closures
Murray Mouth (waters of the sea within 500
metres of the Murray Mouth, from the south
east corner of Younghusband Peninsula to the
south west corner of Sir Richard Peninsula).
−
Goolwa (within 150 m of all barrages).
4
AREAS OF HIGH CONSERVATION
VALUE IN THE COORONG BIOUNIT
Coorong National Park
−
Mulloway, Goolwa Cockle, Shark, Calamari,
Snapper, Snook, Australian Salmon), social
(numerous aboriginal sites-Sir Richard
Peninsula-Ngarrindjeri occupation, grave
sites, aesthetic values, shipwrecks-`Fanny’,
`Margit’, recreational fishing, camping,
4WD’s), national/international (Register of the
National Estate-Coorong National Park,
Wetlands of National Importance-Coorong
Lakes and Lagoon, RAMSAR Wetland of
International
Importance),
practicality
(insulation,
accessibility,
compatibilityadjacent to Coorong National Park and Game
Reserve, Sir Richard Peninsula Coast
Protection Board Reserve).
CURRENT CONSERVATION STATUS
OF THE COORONG BIOUNIT
57
Prime
IUCN
Conservation
Values:
biodiversity, aesthetic, cultural values (IUCN
Category III). IUCN Identification Criteria:
naturalness (not subject to human induced
change), biogeographic (representativeness,
unique coastal dune barrier of the Coorong
Lagoon, record of Pleistocene sea level
change, wide range of coastal and estuarine
habitat
types,
geological
monumentscarbonate lakes), ecological (range of coastal
marine habitats, River Murray estuary-largest
estuary in Australia, internationally important
site for waterbirds and migratory waders,
Hooded Plover nesting areas, seabird
breeding colonies-Little Penguins, Crested
Terns, Caspian Terns, Little Terns, Silver
Gulls, White-breasted Sea Eagles, Little
Falcons, numerous coastal seabird and
waders),
economic
(marine
scalefish-
Prime
IUCN
Conservation
Values:
biodiversity, cultural, social values (IUCN
Category IA). IUCN Identification Criteria:
naturalness (not subject to human induced
change), biogeographic (transition zone
between the Maugean and the Flindersian
biogeographical regions, coastal upwelling,
`Granites’, Lacepede Bay beach ridge plains),
ecological (high diversity of fauna and flora,
wide range of community and habitat types,
extensive seagrass meadows, endangered
Leafy Sea Dragon, kelp forests, cetaceans,
endangered Southern Right Whale, Orangebellied Parrot), economic (fisheries-Southern
Rock Lobster, Abalone, Australian Salmon,
Shark, tourism-Kingston), social (shipwreck`Maria’ and burial site, `Margaret Brock’),
scientific (Southern Rock Lobster research),
national (Butcher’s Gap Conservation ParkRegister of the National Estate, Wetland of
National
Importance),
practicality
(accessibility,
insulation,
compatibilityadjacent to Cape Jaffa Rock Lobster
Sanctuary, Butcher’s Gap Conservation
Park).
58
57
An extension of the existing boundaries of the Coorong National
Park, to include the coastal reserve of Sir Richard Peninsula, has
recently been proposed by Edyvane et al. (1996), in order to
manage the Lower Murray estuary.
Due to it’s unique marine flora and fauna, Margaret Brock Reef
was recommended as an Aquatic Reserve by the South East Coast
Protection Board (UEPG 1982).
59
Lacepede Bay was recommended as a scientific reserve by the
South East Coast Protection Board (UEPG 1982).
Page 251
SOUTH-EAST COAST REGION – CANUNDA BIOUNIT
XXIX MARINE BIOGEOGRAPHY AND CONSERVATION VALUES OF THE
CANUNDA BIOUNIT
The Canunda Biounit extends south from Cape Jaffa to Cape Banks and covers an area of 233,897 ha and a
coastal distance of 140 kilometres. It is oriented in a southwesterly direction into the Southern Ocean
MARINE BIOGEOGRAPHY
3
BIOLOGY
Major Inshore Habitats
1
OCEANOGRAPHY
The coast of this biounit is exposed to both low and
high energy wave energies. Low wave energy
occurs in Wright, Guichen and Rivoli Bays due to
attenuation by offshore reefs. The straight coast of
Canunda, however, has a very high energy
dissipative surfzone due to the general absence of
reefs.
−
Major intertidal habitats in the region include
mostly exposed limestone rocky shores, bays
and sandy beaches.
−
Of the total inshore subtidal habitats mapped
in the biounit (55,887 ha), limestone reefs
comprise 50,552 ha (90.5%), sandy bottoms
comprise 5,333 ha (9.5%), and seagrass
meadows comprise 2 ha (<0.1%).
The coastline from Cape Buffon to Cape Banks
receives the highest break of wave energy in the
South East (Short & Hesp 1984).
Waters in this biounit are cold temperate and
typified by the localised, regular, seasonal cold,
nutrient-rich upwellings near Robe and South End
(Lewis 1981). Mean sea surface temperatures vary
from 140C in winter to 180C in summer (decreasing
to 11-120C under the influence of the upwellings).
The upwellings are significant along the southern
Australian coastline and contribute directly to the
considerable productivity of the region.
2
GEOLOGY
AND
GEOMORPHOLOGY60
COASTAL
A highly irregular coastal topography, producing
marked variations in wave attenuation and
refraction across the nearshore, and breaker wave
power at the shoreline. The resulting highly
variable breaker wave power, coupled with
dunerock exposures, has generated a variable
shoreline morphology including rocky sea-cliffs
fronted by intertidal shore platforms and sandy
beaches ranging from low energy to very high
energy.
There are both stable and unstable
transgressive dune systems.
Five coastal
geomorphological subprovinces are identifiable
within the dunerock coast, each representing a
particular combination of nearshore morphology,
breaker wave energy and backing dunerock-barrier
morphology. For further details refer to Short and
Hesp (1984).
60
From South East Coast Protection District Study Report (UEPG
1982).
Major Benthic Communities
•
−
Macroalgal
Flat limestone platform reefs (comprising
dune aeolianite) dominate most of this region
(eg. Rivoli Bay, Guichen Bay), from 8 metres
(and deeper). Sandy areas occur close to
shore, and also in deeper areas between reefs
(approximately 12 metres), and typically
comprise well-worked coarse to medium sand,
characteristic of high wave-energy conditions.
In exposed areas (13-22 metres depth), kelp
forests occur, dominated by Macrocystis
angustifolia (Giant Kelp) and to a lesser
extent,
Cystophora
platylobium,
Carpoglossum confluens, Ecklonia radiata,
along with species of Caulerpa (particularly
C.longifolia, C.flexilis, C.brownii) and a high
diversity of red algae, and calcareous algae
and animals. Importantly, species of Caulerpa
appear to play a key role in consolidating
sediments on the platform reefs. In sheltered
rocky areas, species of red algae and Caulerpa
(particularly C.flexilis, C.brownii, C.obscura)
continue to dominate, along with Cystophora
monoliformis and to a lesser extent,
C.siliquosa, Scaberia agardhii, Acrocarpia
paniculata, Perithalia caudata and species of
Codium. Significant forests of Macrocystis
occur in the lee of nearshore reefs, and just
offshore, at Cape Dombey (southern Guichen
Bay), Cape Buffon (southern Rivolvi Bay),
and Cape Banks, but are largely absent along
the Canunda Beach region.
Macrocystis
occurs down to 35m but is generally sparse at
depths greater than 25m.
Page 252
SOUTH-EAST COAST REGION – CANUNDA BIOUNIT
•
−
Seagrasses
−
Lake George and Lake Eliza are two of the
remaining wintering grounds in the South East
of the State for the Orange-bellied Parrot,
Neophema chrysogaster and Lake George is an
important wintering ground for the Doublebanded
Plover,
Thinornis
bicinctus.
Threatened species of waterbirds recorded in
the area include the Orange-bellied Parrot (Ne,
Se), Musk Duck, Biziura lobata (Sv), and
Latham’s Snipe, Gallinago hardwickii (Sv). A
total of 42 species of waterbirds have been
recorded in the area: 14 are listed under
international treaties (ANCA 1996). Resident
waterbirds listed under treaties include the
Great Egret, Ardea alba and Cattle Egret,
A.ibis. Black Swans, Cygnus atratus breed on
the lakes. Lake Eliza and Lake George have
been identified as wetlands of international
importance for shorebirds by Watkins (1993).
Lake George is a spawning area for two
species of marine fish, the Yellow-Eye Mullet,
Aldrichetta forsteri, and Flounder.
−
Lake Frome and Mullins Swamp have been
identified as wetlands of national importance
(see ANCA 1996). The area, adjacent to the
Canunda National Park and township of South
End, consists of a very shallow permanent
coastal plain swamp that supports large
patches of fringing aquatic vegetation
interspersed by stretches of open water. From
Mullins Swamp, water passes into Lake
Frome, and ultimately into the sea at the
township of South End. Lake From and
Mullins Swamp provide excellent waterbird
habitat and together are considered to be one
of the major waterbird localities in the lower
south east of the State (ANCA 1996).
Threatened plant species include Melaleuca
squarrosa (Sr).
Threatened species of
waterbirds recorded in the area include the
Musk Duck, Biziura lobata (Sv), Lewin’s Rail,
Rallus pectoralis (Sv), Latham’s Snipe,
Gallinago hardwickii (Sv), Painted Snipe,
Rostratula benghalensis (Sv), Australasian
Bittern,
Botaurus
poiciloptilus
(Sv),
Australasian Shoveler, Anas rhynchotis (Sr),
Baillon’s Crake, Porzana pusilla (Sr) and
Spotless Crake P.tabuensis (Sr). A total of 53
species of waterbirds have been recorded in
the area: 11 are listed under international
treaties. A total of 26 species of waterbirds
breed in the area, including Hardhead,
Australasian Bittern, Lewin’s Rail and
Baillon’s Crake; colonies of Pied Cormorant,
Phalacrocorax melanoleucos, Nakeen Night
Heron, Nycticorax caledonicus, Straw-necked
Ibis, Threskiornis spinicollis, Australian White
Ibis, T.molluca, and Whiskered Tern,
Chlidonias hybridus.
Seagrass habitats in this region are present, but
rare, being mainly confined to the shallow,
sheltered areas of Guichen Bay (Godfrey
Islands), Nora Creina, and southern Rivoli
Bay, Penguin Island), and sheltered interreefal areas. Seagrasses occur in patches or as
sparse meadows and dominated by Posidonia
coriacea, P.australis, Amphibolus antarctica
and Heterozostera tasmanica.
Coastal and Offshore Islands (or Reefs)
−
Margaret Brock Reef (off Cape Jaffa).
−
Baudin Rocks or Godfrey Island (Guichen
Bay).
−
Penguin Island (off Cape Martin, Rivoli Bay).
MARINE CONSERVATION VALUES
1
1.1
SIGNIFICANT
BIOLOGICAL
PHYSICAL FEATURES
AND
Biological
Coastal and Marine Wetlands of National
Importance
−
The coastal salt lakes of Lake Robe (399 ha),
Lake Eliza (4683 ha), Lake St Clair (2566 ha)
and Lake George (5916 ha), have been
identified as wetlands of national importance
(see ANCA 1996). The four lakes are situated
on the coastal plain between the townships of
Robe and Beachport, in the interdune corridor
between the present dune ridge (to the west)
and relict coastal dune (to the east), and are
surrounded by small freshwater ephemeral
wetlands. Lake George is a deep estuarine
lake intermittently connected to the sea. The
coastal wetlands act as a refuge for waterbirds
in the summer or drought (ANCA 1996). The
lakes and groundwater soaks provide a diverse
selection of vegetation structures and wetland
habitats for waterbirds.
Page 253
SOUTH-EAST COAST REGION – CANUNDA BIOUNIT
east. Limestone rises separated by long sandy
beaches occur at intervals along the 11
kilometres coastal strip between Cape Lannes
and Errington Holes. The coastal strip is
between 750m and 2 km wide at points. A
number of small lakes occur, most of which
are brackish.
Two contain permanent
freshwater, providing an important water bird
habitat.
Typical samphire vegetation
(Sarcocornia sp.) and the South Australian
Swamp Paper Bark occurs around the brackish
lakes. It is a significant area as it conserves
remnant coastal vegetation and a chain of
small lakes, and provides habitat for
endangered and vulnerable bird species.
Other significant features include the partially
eroded dune rock of the Robe Range,
fossilised tree roots, rocky headlands that
contain habitat for roosting and nesting birds,
sandy beaches with extensive dunal systems
(major tourist attraction), stabilised dunes that
provided habitat for birds and mammals as
well as providing protection to the small
coastal lakes. The chain of small lakes is an
uncommon feature and not well conserved in
the reserve system. The park is on the
Register of the National Estate. The area is
also a popular reef diving location, with many
giant deep overhangs and swimthroughs, and
is listed in `Dive South Australia: The Best Dive
Sites in South Australia’ (Diving Industry
Association of South Australia).
Resident waterbirds listed under treaties
include the Great Egret, Ardea alba, Glossy
Ibis, Plegadis falcinellus and Painted Snipe.
Mullins Swamp is a Wildlife Sanctuary.
Other Areas of Recognised Conservation
Significance
•
Margaret Brock Reef
−
This limestone reef (like other reefs in this
biounit) possesses unique flora and fauna
related to its position in the transition zone
between the Maugean Subprovince and the
remainder of the Flindersian Province.
Consequently this area is reknown for its rich
diversity of marine flora and fauna. It has
extensive subtidal forests of the Giant Kelp
(Macrocystis angustifolia) and just below low
tide level, extensive zones of Bull Kelp
(Durvillea potatorum).
Both these
communities are typical of cold-water rough
water coasts of the Maugean Subprovince.
The reef is presently a Marine Sanctuary for
the Southern Rock Lobster (Jasus edwardsii)
with removal of lobsters prohibited within
1km of the lighthouse on the reef. Due to it’s
unique marine flora and fauna, Margaret
Brock reef was recommended as an Aquatic
Reserve by the Southeast Coast Protection
Board (1982). The area is also a popular
diving location and is listed in `Dive South
Australia: The Best Dive Sites in South
Australia’ (Diving Industry Association of
South Australia).
•
−
•
−
Baudin Rocks Conservation Park (Guichen
Bay)
This park (also known as Godfrey Island),
comprises several small, rocky islands which
are set aside to protect a breeding colony of
Crested Terns (Sterna bergii) and Little
Penguins (Eudyptula minor). Within Guichen
Bay, there are large forests of Giant Kelp
(Macrocystis angustifolia) which act as shelter
for numerous species of fish, molluscs and
crustacea (including Southern Rock Lobster).
The kelp also contributes ecologically to the
marine ecosystem via detritus which following
decay becomes incorporated into the food
web. Intertidal and subtidal seagrass beds in
this bay (and other bays in the region) are also
important for the Southern Rock Lobster
which shelter and feed in these areas. Baudin
Rocks Conservation Park is on the Register of
the National Estate.
Little Dip Conservation Park:
A large coastal park featuring a complex sand
dune system with cliffs, shore platforms, reefs
and islets to the west and large salt lakes to the
•
Nora Creina Bay
−
This bay was recommended as an aquatic
reserve by the South East Coast Protection
Board (1982), with consideration to be given
to permitting line fishing in the reserve as a
number of migratory species frequently move
through the area. The bay is also a regular
spot for marine education and scientific
studies by the University of Adelaide and SA
Herbarium.
•
−
Beachport Conservation Park
Beachport Conservation Park is situated
between the Southern Ocean and Lake
George. A diverse range of habitats exist
within the park, including mobile sand dunes
and a freshwater lake known as Two Lakes.
The adjoining coastal and lake environments
supports approximately 200 species of birds.
The margin of Lake George is a particularly
important area for migratory waders such as
the Grey Plovers (Pluvialis squaterola),
Mongolian Sand Dotterels (Charadrius
mongolus), Green shanks (Tringa nebularia)
and Bar-tailed Godwits (Limosa lapponica).
The park also contains extensive areas of
Aboriginal middens. The park is on the
Register of the National Estate. The area is
Page 254
SOUTH-EAST COAST REGION – CANUNDA BIOUNIT
also a popular reef diving location, with many
swimthroughs, gutters and ledges, and is listed
in `Dive South Australia: The Best Dive Sites in
South Australia’ (Diving Industry Association
of South Australia).
•
−
•
−
Penguin Island Conservation Park and
Rivoli Bay
Penguin Island is a breeding ground for Little
Penguins, Crested Terns, Silver Gulls (Larus
novaehollandiae) and Black-faced Shags
(Leucocarbo fuscesens). Australian Sea Lions
are occasional visitors.
Penguin Island
Conservation Park is on the Register of the
National Estate. The limestone reef in this
area is presently a Marine Sanctuary for the
Southern Rock Lobster (Jasus edwardsii) with
removal of lobsters prohibited within 100m of
any part of the coast of Penguin Island and
that portion of Rivoli Bay as defined in the
proclamation.
Because of its public
accessibility and tourism potential to
Beachport, Penguin Island was recommended
as an Aquatic Reserve by the South East Coast
Protection Board (1982).
Canunda National Park
This area was set aside to preserve and protect
a representative sample of the coastal
environment of the South East. The northern
coast of this park contains spectacular
limestone outcrops and offshore reefs. The
remainder of coastline consists of a long sandy
beach and a complex system of mobile dunes
which are the most massive (up to 60m high,
and extending 5km inland) and unstable dune
systems in the South East region (Short &
Hesp 1980). The south coast beach is backed
by low fore-dunes.
There are a number of freshwater soaks
supporting ephemeral swamp vegetation such
as at Whale Rock and between Jacky Point and
Number One Rock. Over the years the Ocean
Beach at Canunda has seen many strandings of
mainly vagrant marine mammals and oceanic
birds. Other features include habitat for rare
species and birds (Orange-bellied Parrot and
the Swamp Antechinus), numerous Aboriginal
middens, hearths, stone ovens and campsites
and features associated with European
settlement such as the Old Ellis Homestead.
The park is on the Register of the National
Estate.
•
−
Cape Banks
This area was recommended as an aquatic
reserve by the South East Coast Protection
Board (1982), with consideration to be given
to prohibiting spearfishing and the taking of
lobsters by divers, but the use of lobster pots
to be permitted, owing to the importance of
the area to the lobster industry.
•
−
1.2
Southern Right Whale (Eubalaena australis)
The endangered Southern Right Whale
(Eubalaena australis) is often sighted each
year along this region of coast from May-June.
This region is probably part of the migratory
path of whales which tend to move from the
cooler waters of Tasmania, to the warmer
waters of the Head of the Great Australian
Bight, where they give birth and nurse their
young (J.Ling, SA Museum, pers.comm.).
Physical
−
Presence of nutrient-rich coastal upwellings
near Robe and South End. These upwellings
are unique along the southern Australian
coastline and contribute directly to the
considerable productivity of the region.
−
The beach ridge plains of Lacepede, Guichen
and Rivoli bays and the Pleistocene calcrete
formations of the Robe range between Robe
and Beachport are important geological and
geomorphological areas.
−
Canunda beach is a spectacular high energy
beach (see above).
Geological Monuments
−
Guichen Bay Conservation Park (including
Cape Thomas). On the Register of the
National Estate.
−
Baudin Rocks Conservation Park (Godfrey
Islands). On the Register of the National
Estate.
−
Cape Dombey: coastal features such as the
blowhole and the aeolianite arch.
−
Little Dip Conservation Park: includes part of
Robe Dune Ridge.
−
Beachport Conservation Park, Cape Martin,
Cowrie and Penguin Island.
Beachport
Conservation Park and Penguin Island are on
the Register of the National Estate.
Carpenters Rocks to Cape Banks, including
Admella Dunes: Gambier Limestone with
shore platforms - transgressive Holocene
Dunes - cliff is retreating).
−
2
2.1
OTHER VALUES
Commercial Fisheries
Page 255
SOUTH-EAST COAST REGION – CANUNDA BIOUNIT
The main single species fisheries in this biounit are
the Southern Rock Lobster (Jasus edwardsii) and
Abalone industries. Boats at Beachport, Carpenter
Rocks, Robe, Nora Creina and Southend together
account for nearly 48% of the total number for the
Southern Zone. Of these, Robe and Nora Creina
have approximately a third of the boat numbers
within this biounit.
Southern Rock Lobster
This biounit is the most significant region for
Southern Rock Lobster fishing in South Australia.
The region encompasses 2 fishing zones: the waters
from Cape Jaffa to Cape Martin (Fishing Zone 55)
and the waters from Cape Martin to Nene Valley
(Fishing Zone 56). In 1995/96 and 1996/97 a total
of 85 and 78 licensed operators fished in the
northern section of this biounit (ie. Fishing Zone
55), catching approximately 635,945 and 629,222
kg of lobsters, respectively (or 12.43% and 12.30%
of the total catch for Southern Rock Lobster in
South Australian waters).
Similarly, in the southern section of this biounit,
effort and production is also high. In 1995/96 and
1996/97 a total of 66 and 60 licensed operators
fished in the southern section of the Canunda
Biounit (ie. Fishing Zone 56), catching
approximately 539,764 and 499,739 kg of lobsters,
respectively (or 10.55% and 9.77% of the total
catch for Southern Rock Lobster in South
Australian waters). Within this one biounit, lobster
catch for 1995/96 and 1996/97 represented
approximately 22.99% and 22.07% of the total
catch for Southern Rock Lobster in South
Australian waters.
Abalone
This biounit represents some of the most significant
areas for the commercial harvest of Blacklip
Abalone in South Australia. Areas such as Rivoli
Bay and the coastal reefs adjacent to Lake Bonney
are particularly productive areas in this region. In
1994/95 and 1995/96 a total of 74,606 and 52,668
kg of Blacklip was harvested within this region (ie.
MapCode 33A-C, 34A-D, 35A-E, 36A-C, 37AH,
38B-H, Cape Jaffa to Cape Banks region), which
represented 51.9% and 36.9% of the total Blacklip
Southern Zone catch (or 15.09% and 11.38% of the
total catch for Blacklip in South Australian waters),
but due to confidentiality constraints these figures
are not available.
commercial marine scalefish species from the
northern section of this biounit (ie. Fishing Zone
55), respectively.
License holders expended
approximately 1922 and 1910 boat days effort
fishing these waters during 1995/96 and 1996/97,
respectively. The marine scalefish catch for this
region (ie. Fishing Zone 55) represented 92,391 kg
in 1995/96 and 56071 kg in 1996/97(or 0.89% and
0.55% of the total catch for the marine scalefish
fishery in South Australian waters). In the southern
section of this biounit, south of Cape Martin (ie.
Fishing Zone 56), a total of 37 and 32 licensed
operators fished 2,387 and 2,833 days in this region
in 1995/96 and 1996/97, catching approximately
80,518 and 59,807 kg, respectively (or 0.77% and
0.59% of the total catch for the marine scalefish
fishery in South Australian waters).
There is a relatively small amount of salmon netting
(a few tonnes) which is used chiefly as bait for
lobster around Beachport.
At the mouth of Lake George there are 1 or 2
commercial net fishers, targeting Sea and Yellow
Eye Mullets, Mulloway and Australian Salmon.
There is a substantial offshore marine
fishery in this area especially at the shelf
100m-900m and around the submarine
using deep lines for Blue Eye
(Hyperoglyphe antarctica).
scalefish
edges at
canyons
Trevalla
A large shark fishery at 20m-100m depth using large
mesh gill nets exists mainly for School Shark
(Galeorhinus australis) and Gummy Shark
(Mustelus antarcticus).
The south-east trawl fishery is also substantial in this
biounit with 75% of the boats used being based at
Beachport. Trawling occurs in the deep canyons for
Orange Roughy (Hoplostethus atlanticus), and at
300m-1200m for Gem Fish and for Grenadier at the
continental shelf. There is no inshore trawling
mainly due to the rough bottom.
Other commercial species include Tommy Ruff,
King George Whiting and Garfish.
Although license holders are not restricted to fishing
in this biounit, the following licenses are registered
in this area:
−
Southend: 1 abalone, 25 Southern Rock
Lobster, 1 unrestricted marine scalefish.
−
Nora Creina: 1 Southern Rock Lobster.
−
Robe: 27 Southern Rock
unrestricted marine scalefish.
−
Beachport: 22 Southern Rock Lobster.
Marine Scalefish Fisheries
The Canunda Biounit encompasses 2 fishing zones:
Fishing Zone 55 and 56. During 1995/96 and
1996/97, 48 and 37 commercial licence holders
(made up of Marine Scalefish and Restricted
Marine Scalefish licence categories) caught
Lobster,
2
Page 256
SOUTH-EAST COAST REGION – CANUNDA BIOUNIT
−
Carpenter Rocks: 14 Southern Rock Lobster.
−
Cape Jaffa: 15 Southern Rock Lobster, 2
unrestricted marine scalefish
2.2
−
Aquaculture
A research and development site has been approved
for trialing salmon aquaculture in this region near
Cape Jaffa and another site has been sought near
Robe. Additional interest has been expressed in
undertaking trials for kelp culture in Lacepede Bay
and around Cape Jaffa. No other marine-based
aquaculture interests current exists in this region.
The South East Aquaculture Management Plan
(Gilliland 1996) proposes limited aquaculture
development in this region:
Robe Policy Area
−
Robe Aquaculture Zone (ie. offshore Little
Dip Conservation Park) – licenses will be
considered for a maximum of 40 ha of
aquaculture in this zone.
−
Robe Exclusion Zone (ie. inshore waters
adjacent to Bernouilli, Baudin Rocks, Little
Dip, Beachport Penguin Island Conservation
Parks, Nora Creina Bay, Cape Buffon) –
licenses will not be considered for aquaculture
in this zone.
−
Robe Zone (ie. remaining waters, inshore and
offshore, from Cape Jaffa to Cape Buffon) –
licenses will be considered for aquaculture
development greater than 60 ha, or for
intertidal oyster culture.
2.3
Port MacDonnell Exclusion Zone (ie. inshore
waters adjacent Canunda National park, Nene
Valley and Piccaninnie Ponds Conservation
Parks, including Carpenters Rocks and
Blackfellows Caves, Douglas Point, and
Middle Point to Stony Point) – licenses will
not
be
considered
for
aquaculture
development in this zone.
Recreation and Tourism
Fishing
−
Robe: jetty, breakwater, boat, beach and rock
fishing. Major species: King George Whiting,
Yellow-fin Whiting, Black Bream, Sand
Flathead, Yellow-eye Mullet, Australian
Salmon, Snapper, Mulloway, Sweep, Southern
Rock Lobster, and Toothbrush Leatherjacket.
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Nora Creina: rock, boat and beach fishing.
Major species: King George Whiting, Yelloweye Mullet, Australian Salmon, Snapper,
Sweep, Garfish, Southern Rock Lobster, and
Toothbrush Leatherjacket.
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Beachport: jetty, boat and rock fishing. Major
species: King George Whiting, Black Bream,
Sand Flathead, Yellow-eye Mullet, Australian
Salmon, Snapper, Mulloway, Sweep, Garfish,
Flounder, Southern Rock Lobster, Tommy
Rough, Trevally, Toothbrush leatherjacket,
and Southern Calamari.
Tourism
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Robe and Beachport: attract the largest
numbers of visitors in the South East and as
such are important tourist destinations. Main
activities include recreational fishing and
sightseeing.
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Boatswain: swimming, boating, jetty fishing,
scenic area.
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Robe and Guichen Bay: sailing, boating,
swimming, jetty fishing, scenic area, historic
area, diving. The 10km of beach in Guichen
bay is the most intensively used beach along
the South East.
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Nora Creina: swimming, boating, fishing,
scenic area, holiday shacks. Popular area for
students of marine biology as there is a great
diversity of marine life.
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Beachport: sailing, boating, swimming, jetty
fishing, scenic area, historic area, surfing.
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Sout