Download Waterbird Monitoring of Lakes Alexandrina and Albert

Condition Monitoring of the Lower Lakes, Coorong and Murray Mouth
Icon Site: Waterbirds using the Lower Lakes in 2012
David C Paton & Colin P Bailey
June 2012
School of Earth & Environmental Sciences
University of Adelaide
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Condition monitoring of the Lower Lakes, Coorong and Murray Mouth
Icon Site: Waterbirds using the Lower Lakes in 2012
David C. Paton & Colin P. Bailey
School of Earth & Environmental Sciences
University of Adelaide
© Copyright Commonwealth of Australia 2012.
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This document has been prepared for the Murray-Darling Basin Authority and is made available for general use and to
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resources. The opinions, comments and analysis (including those of third parties) expressed in this document are for
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may result in changes to the approaches set out in this document.
Front image: Latham’s Snipe. Image courtesy of Fiona Paton
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EXECUTIVE SUMMARY
The number of waterbirds using Lakes Alexandrina and Albert were counted between 9 and 21
January 2012. Identical methods were used to those used in previous years with the shorelines of
each Lake broken into a series of 1km x 1km grid cells with all waterbirds counted in each of 470
grid cells that contained shoreline and or shallow water suitable for use by waterbirds.
In January 2012 over 74,000 waterbirds were counted using the Lower Lakes, with more than
30,000 using both Lake Albert and Lake Alexandrina (excluding the Goolwa Channel), and nearly
9,000 using the Goolwa Channel. These abundances were approximately double those of the
previous year with many species having increased in both abundance and distribution. These
increases in abundance appear to be driven by influxes of birds from other wetlands rather than
breeding activity within the Lower Lakes. The most abundant species was the Australian Shelduck
(Tadorna tadornoides) which accounted for nearly 30% of all birds. Other prominent species (>
2,000 individuals counted) were Australian Pelican (Pelecanus conspicillatus), Pied Cormorant
(Phalacrocorax varius), Great Cormorant (P. carbo), Little Black Cormorant (P. sulcirostris), Cape
Barren Goose (Cereopsis novaehollandiae), Pacific Black Duck (Anas superciliosa), Grey Teal (A
gracilis), Eurasian Coot (Fulica atra), Straw-necked Ibis (Threskiornis spinicollis), Silver Gull
Chroicocephalus novaehollandiae) and Whiskered Tern (Chlidonias hybridus). Black Swans
(Cygnus atratus) and Australian White Ibis (Threskiornis mollucca) were the only other species to
exceed 1,000 birds.
A number of additional species were detected for the first time in the four years of monitoring in
January 2012, including Australasian Grebe (Tachybaptus novaehollandiae), Freckled Duck
(Stictonetta naevosa), Pink-eared Duck (Malachorhynchus membranaceus), Spotless Crake
(Porzana tabuensis), Cattle Egret (Ardea ibis), Glossy Ibis (Plegadis falcinellis) and Australasian
Bittern (Botaurus poicoloptilus). Latham’s Snipe (Gallinago hardwickii), Black-tailed Native Hens
(Tribonyx ventralis), Hoary-headed Grebes (Poliocephalus poliocephalus) and Australian Crakes
(Porzana fluminea) were also seen in slightly higher numbers and or in more locations in January
2012 than in previous years. These suggest a broad influx of birds into the Lower Lakes.
Although eleven species of shorebird (stilts, avocets, plovers, dotterels, sandpipers, stint and
greenshank) were recorded, none of these species accounted for large numbers of birds. Of these
the abundances of Common Greenshank (Tringa nebularia) had declined further reflecting similar
declines in the adjacent Coorong, and suggesting this species is faring poorly across the Lower
Lakes, Coorong and Murray Mouth (LLCMM) Icon Site. Other species that maintained low numbers
or continued to decline were the Yellow-billed (Platalea flavipes) and Royal (P. regia) Spoonbills.
Of the sixteen species of waterbird selected for more detailed assessment in the LLCMM Icon site,
fourteen were detected in the Lower Lakes in January 2012. However, only two abundant
widespread species (Australian Pelican, Black Swan) amongst this list were in numbers potentially
exceeding 1% flyway populations. None of the other species came close to meeting this
requirement. Most of the other species have consistently used the Coorong to a much greater extent
than the Lower Lakes.
The distributions and abundances of waterbirds using the Lower Lakes are likely to continue to
change, and ongoing monitoring is recommended, along with additional work aimed at
understanding the habitat needs and movements of waterbirds. A better understanding of the
ecology of the waterbirds is needed before the Lower Lakes can be managed to maintain and
improve outcomes for waterbirds in the region.
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BACKGROUND
The Lower Lakes, Coorong and Murray Mouth (LLCMM) region is a Wetland of International
Importance under the Ramsar Convention and is one of the Icon Sites within the Murray-Darling
Basin. Large numbers of small migratory and non-migratory waders (sandpipers, plovers, stilts),
piscivorous birds (pelicans, cormorants, grebes, terns) and waterfowl (swans, duck) use
components of this wetland system, particularly during summer (e.g. Paton 2010).This abundance
and diversity of waterbirds was one of the prime reasons for the LLCMM being listing as a Wetland
of International Importance. As a permanent wetland system the area is particularly important during
droughts.
Waterbird use of the Lower Lakes component of the LLCMM has been assessed annually since
2009, while the Coorong and Murray Mouth region has been assessed annually since 2000 with the
counts taking place during summer when the extent of use of this wetland system by birds is highest
(Paton 2010). These systematic counts are then used to document changes in the distributions and
abundances of waterbirds within the different components of the LLCMM and in recent years this
annual census has been used to assess various waterbird-related targets listed in the LLCMM Icon
Site Environmental Monitoring Plan (MDBC 2006; Rogers & Paton 2008; Paton & Rogers 2009;
Paton et al. 2009; SA MDB NRM Board 2009; Rogers et al. 2009; Paton & Bailey 2010a,b;
2011a,b).
This report summarises the counts of waterbirds for the Lower Lakes region of the LLCMM Icon site
that were undertaken in January 2012, the fourth year of monitoring. Over the four years of
monitoring the water levels in the Lower Lakes have changed dramatically, from the unprecedented
levels in 2009 and 2010 when the levels were below sea level (-0.7m to -0.9m AHD in Lake
Alexandrina; and -0.5m AHD in Lake Albert) to more typical water levels of around +0.65m AHD in
2011 and 2012. With these changes in water levels there were dramatic changes in the waterbird
communities using the Lower Lakes. For example in 2009 and 2010 there were tens of thousands of
stints and sandpipers foraging around the shorelines of the Lower Lakes taking advantage of rarely
exposed mudflats. However when water levels were re-instated and returned to more typical levels
in late 2010 the once extensive areas of mudflat that were covered with shallow water in 2009 and
2010 were now covered with deep water. This effectively excluded wading birds like stints and
sandpipers and consequently they had all but disappeared when the counts were undertaken in
January 2011 (e.g. Paton & Bailey 2010b, 2011b). In January 2011 slightly fewer than 40,000
waterbirds were using the Lower Lakes, compared to 80,000-110,000 in the previous two years with
many species having declined in abundance (Paton & Bailey 2011b). A few species, however, were
increasing in abundance and distribution in January 2011. Water levels in January 2012 were similar
to those of January 2011, and typical of the levels expected in the Lakes under current management
goals. Given this few sandpipers, stints and plovers were expected to be using the shorelines and
the abundance and distribution of waterbirds was expected to be similar to those detected in
January 2011 (Paton & Bailey 2011b). The purpose of the ongoing monitoring, in addition to
meeting reporting requirements for the Icon site, was to document any further changes in the
waterbird community given that more typical water levels were being maintained.
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METHODS
Waterbird Census
Waterbirds were counted around the shores of Lake Alexandrina and Lake Albert (Lower Lakes)
between 9 January and 21 January 2012, with a total of 10 survey days. The shorelines of each lake
were divided into 1 km x 1 km grid cells (based on Transverse Mercator Projection, Map Grid of
Australia (MGA94), Zone 54) and the numbers of birds present in each grid cell were recorded along
with their activity (Foraging, Flying Over, Resting, Breeding), allowing both the abundance and the
distribution of birds over the Lower Lakes to be determined. Grid cells, however, differed in the
amount of shoreline present and also in the extent of shallow water but no adjustments of the
numbers of birds was undertaken to account for any differences in grid cells. The time spent
surveying each 1km x 1km grid also varied depending on the length of shoreline and aquatic habitat
and the ease with which the cell could be covered. The time spent in each cell was set as the time
required to cover all aquatic habitat and count all of the birds within the cell. Usually two or three
observers worked collaboratively to cover each grid cell. In all, 470 grid cells (111 around Lake
Albert, 287 around Lake Alexandrina and a further 72 which covered the Goolwa Channel and
related tributaries) were visited in January 2012, with all cells containing shoreline being surveyed.
Within each section, shoreline counts of waterbirds were conducted either by foot or from a small
boat or both depending on the extent of backwaters and ease of access with a boat to the shoreline.
During the counts, the location of observers was continuously verified using hand-held GPS units to
ensure the integrity of data for each section of shoreline.
All waterbird observations were made using either binoculars (8-10x magnification), or spotting
scopes (20x-60x magnification). Birds were identified to species, counted, and their activity
classified to one of four categories (foraging, resting, flying-over or breeding).
RESULTS & DISCUSSION
Abundance of waterbirds using the Lower Lakes in 2012
A total of 60 waterbird species were recorded during the 2012 census including two domesticated
species. More than 74,600 waterbirds were counted, with the smaller Lake Albert supporting
comparable numbers of waterbirds to Lake Alexandrina, 34,905 and 30,708 respectively. The
numbers of waterbirds using the Goolwa Channel were substantially lower (8,989) than the two
Lakes but consistent with this region being smaller than the others (Table 1). Compared with the
2011 census, the numbers of birds using each of these component wetlands was approximately
double.
The most prominent species within the Lower Lakes region in January 2012 was Australian
Shelduck (Tadorna tadornoides) accounting for nearly 30% of all the birds counted (21,973). Most of
the shelduck were associated with Lake Albert (Table 1) Eleven other species exceeded 2,000
individuals: Australian Pelican (Pelecanus conspicillatus), Pied Cormorant (Phalacrocorax varius)
Great Cormorant (P. carbo), Little Black Cormorant (P. sulcirostris),Cape Barren Goose (Cereopsis
novaehollandiae), Pacific Black Duck (Anas superciliosa), Grey Teal (A. gracilis), Eurasian Coot
(Fulica atra), Straw-necked Ibis (Threskiornis spinicollis), Silver Gull (Chroicocephalus
novaehollandiae) and Whiskered Tern (Chlidonias hybridus). The only other abundant species (>
1,000 individuals) were the Black Swan (Cygnus atratus) and the Australian White Ibis (Theskiornis
mollucca). With the exception of the ibis, these abundant species were either fish-eating species
(cormorants, pelican, and terns) or herbivorous species that grazed plants for nutrition. At least two
species, Australian Shelduck and Cape Barren Geese, fed extensively on pasture or grain in
paddocks adjacent to the Lower Lakes.
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Although eleven species of shorebird (stilts, avocets, plovers, dotterels, sandpipers, stint and
greenshank) were recorded, none of these species accounted for large numbers of birds (Table 1).
Of the sixteen bird species that have been selected for condition monitoring of the Lower Lakes,
Coorong and Murray Mouth Icon Site, fourteen were detected using the Lower Lakes in January
2012 (Table 2). The two species that were not detected (Sanderling Calidris alba, Pied
Oystercatcher Haematopus longirostris) generally favour more saline environments and would not
be expected to use freshwater wetlands frequently. Of the fourteen species that were detected, the
abundances of only two species potentially exceeded their 1% global population sizes: Australian
Pelican and Black Swan (Table 2). The other species fell well short of the 1% level, and would not
be expected to reach these levels in the Lower Lakes. For at least twelve of the listed species the
Coorong is used much more extensively than the Lower Lakes (e.g. Paton & Bailey 2012). This was
certainly the case for Sharp-tailed Sandpipers (Calidris acuminata), Curlew Sandpipers (C.
ferruginea), Red-necked Stints (C. ruficollis), Common Greenshanks (Tringa nebularia), Chestnut
Teal (Anas castanea), Red-capped Plovers (Charadrius ruficapillus), Pied Oystercatchers,
Australian Pelicans, Banded Stilts (Cladorhynchus leucocephalus), Red-necked Avocets
(Recurvirostra novaehollandiae), and Fairy Terns (Sternula nereis) in January 2012, while the
numbers of Black Swans using the Coorong were comparable to those using the Lower Lakes in
January 2012. Of the other species, the Australasian Bittern (Botaurus poiciloptilus), Latham’s Snipe
(Gallinago hardwickii) and Australian Crake (Porzana fluminea) are all cryptic species that occur
only in small numbers. Although these species have been recorded fairly regularly around the Lower
Lakes in the past, they have never been recorded in large numbers and so even historically they are
unlikely to have ever exceeded the 1% global population level.
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Table 1. Abundance of all waterbird species recorded during the January 2012 census of Lake Albert, Lake
Alexandrina and Goolwa Channel, including birds of prey and reed-frequenting passerines
Bird Species
(Common Name)
Australian Pelican
Lake
Albert
634
Lake
Alexandrina
1825
Goolwa
Channel
239
Total
10
94
20
124
1130
2734
91
3955
79
228
90
397
Great Cormorant
1339
6813
1219
9371
Little Black Cormorant
972
526
593
2091
3
3
Darter
Status*
SA; EPBC; IUCN
RA;
Pied Cormorant
Little Pied Cormorant
Black-faced Cormorant
Australasian Grebe
Hoary-headed Grebe
Great Crested Grebe
RA;
Black Swan
Cape Barren Goose
RA;
2698
7
4
60
71
5
18
13
36
11
78
19
108
324
553
457
1334
512
1679
16
2207
Domestic Goose
27
27
Australian Wood Duck
35
19
54
Australian Shelduck
19199
2309
465
21973
Pacific Black Duck
1904
3047
800
5751
Mallard (Domestic Duck)
10
Grey Teal
10
3082
2187
511
5780
8
87
16
111
7
1
1
10
Hardhead
45
42
21
108
Pink-eared Duck
164
52
34
250
Chestnut Teal
Australasian Shoveler
RA;
Freckled Duck
VUL;
Musk Duck
RA;
Blue-billed Duck
RA;
Australian (Spotted) Crake
9
9
1
1
2
2
3
25
2
2
Purple Swamphen
19
115
312
446
Dusky Moorhen
11
2
31
44
Eurasian Coot
856
1074
1720
3650
27
64
42
133
3
1
3
7
Spotless Crake
RA;
Black-tailed Native Hen
Latham’s Snipe
RA; MIG
White-faced Heron
28
31
74
27
132
Eastern Great Egret
MIG
127
202
59
388
Little Egret
RA;
4
1
5
Cattle Egret
RA; MIG
Nankeen Night Heron
Australasian Bittern
Australian White Ibis
VUL; END; END
447
8
8
8
8
1
1
448
7
178
1073
Bird Species
(Common Name)
Status*
SA; EPBC;
IUCN
Straw-necked Ibis
Glossy Ibis
RA; MIG
Royal Spoonbill
Yellow-billed Spoonbill
Lake
Albert
Lake
Alexandrina
Goolwa
Channel
Total
1330
1065
191
2586
17
16
28
61
38
59
28
125
8
21
1
12
Eastern Curlew
MIG
3
1
4
Common Greenshank
MIG
7
6
13
Marsh Sandpiper
MIG
1
5
6
Sharp-tailed Sandpiper
MIG
178
270
Curlew Sandpiper
MIG
1
Red-necked Stint
MIG
165
136
42
21
Red-kneed Dotterel
Red-capped Plover
Banded Stilt
456
1
1
VUL
Black-winged Stilt
8
39
14
77
1
2
29
29
155
Red-necked Avocet
301
70
10
264
10
Masked Lapwing
150
233
64
447
Silver Gull
1285
730
732
2747
645
3076
627
4348
79
285
94
458
18
235
56
309
Whiskered Tern
Caspian Tern
MIG
Crested Tern
Fairy Tern
White-bellied Sea-Eagle
END; VUL; VUL
11
11
END; MIG
Whistling Kite
Swamp Harrier
2
# species
1
1
MIG
2
6
1
9
13
1
14
8
15
5
28
34995
30748
8996
74739
52
58
45
66
Little Grassbird**
TOTAL
3
2
Golden-headed Cisticola**
Clamorous Reed-Warbler**
3
*State NPW Act listed species where END=endangered; VUL = Vulnerable; RA = Rare
EPBC listed species where END= endangered; VUL = Vulnerable; M = Migratory
IUCN listed species where END = endangered; VUL =Vulnerable
**counts for these species are under-estimates because these species use dense vegetation and only
detected if they call
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Table 2. Counts for LLCMM Icon Site selected bird species for Lakes Albert and Alexandrina (including
1
Goolwa Channel) in January 2012. 1% flyway populations based on Wetlands International (2006), – based
2
on global population estimates for Australian wintering population, – based on global population estimate for
3
south-eastern Australian subspecies/population, – recent counts (e.g. Wainwright & Christie 2008, Kearney
et al. 2008) suggested total global population for Banded Stilt is around 300,000.
Species
1% flyway
n
popul
Lake
Albert
Lake
Alexandrina
TOTAL
1600
1
1800
3200
220
1000
1000
178
1
165
278
136
456
1
301
3
7
4
6
7
13
8
103
1
1
1010
111
1
2
1334
2064
25
29
10
2698
28
29
10
11
Migratory
Sharp-tailed Sandpiper Calidris acuminata
Curlew Sandpiper C. ferruginea
Red-necked Stint C. ruficollis
Sanderling C. alba
Latham’s Snipe Gallinago hardwickii
Common Greenshank Tringa nebularia
Resident
2
Chestnut Teal Anas castanea
Australasian Bittern Botaurus poiciloptilus
Red-capped Plover Charadrius ruficapillus
Black Swan Cygnus atratus
Pied Oystercatcher Haematopus longirostris
Australian Pelican Pelecanus conspicillatus
Australian Crake Porzana fluminea
Banded Stilt Cladorhynchus leucocephalus
Red -necked Avocet Recurvirostra novaehollandiae
Fairy Tern Sternula nereis
1000
25
950
>1000
110
>1000
1600
3
3000
1070
2
26
9
1
324
634
3
11
Changes to the distributions and abundances of waterbirds 2009-2012
Changes in the abundances of waterbirds using the Lower Lakes over the last four years need to be
placed in perspective. Prior to the recent millennium drought, water levels in the Lower Lakes were
consistently around 0.5-0.7m AHD. However when systematic counts of waterbirds in the Lower
Lakes commenced in 2009 water levels in the Lower Lakes were the lowest on record (with levels
around –0.75m for Lake Alexandrina and -0.5m AHD for Lake Albert). Most of the fringing and
emergent vegetation was distant from the waterline at this time and there were extensive areas of
exposed mudflats. The conditions had deteriorated further by the 2010 counts with water levels in
Lake Alexandrina around -0.9m AHD and those in Lake Albert still managed at around -0.5m AHD.
However, water levels in the Goolwa Channel, a component of Lake Alexandrina, had been
artificially recovered with the use of a bund at Clayton coupled with some supplementary pumping of
water into this section. Thus counts undertaken in 2009 and 2010 were unlikely to be typical of
waterbird use of the Lower Lakes.
By January 2011 water had returned to the Lower Lakes with average water levels at the time of the
waterbird census being around +0.66m AHD, while those in January 2012 were +0.68m AHD. In
general the water levels in the Lower Lakes have fluctuated between 0.5 and 0.8m AHD,
occasionally as high as 0.9m AHD over the last year or so. These water levels are more typical of
the water levels that were experienced in the Lower Lakes prior to the drought.
Without counts of waterbirds prior to the drought, assessing the recovery of waterbird populations in
the Lower Lakes is difficult. Certainly when water levels were low a range of species were likely to
have been excluded, particularly species that use fringing vegetation for cover such as Purple
Swamphens (Porphyrio porphyrio). However other species may have benefitted, for example some
of the shorebirds like Red-necked Stints, Sharp-tailed Sandpipers and Red-capped Plovers which
forage on damp mud flats or mudflats covered in shallow (<5cm) water (Table 3). With the return of
water and the flooding of the mudflats many of these shorebirds were likely to be excluded from
most of the shorelines and, in fact, all three species have largely vacated the Lakes for the last two
years (Table 3, Paton & Bailey 2011a). With higher water levels and the re-connection of the fringing
vegetation with the water, species like Purple Swamphens might be expected to re-colonise as
appears to be the case (Table 3). However there are marked differences in the rates of potential recolonisation between the different components of the Lower Lakes for this species with higher
absolute and relative abundances in the Goolwa Channel, than either Lake Albert or Lake
Alexandrina (Table 1). This is likely to be related to the earlier return of water to the Goolwa Channel
and the longer period of time (an extra year) with which the water in the Channel had been reconnected with the fringing vegetation. Much of the interest in following the changes in waterbird
communities is to document the rate of re-colonisation of the Lower Lakes by various waterfowl. At
present it is not known if the waterbird community has fully recovered or whether the distributions
and abundances will continue to change over time.
There is a clear need to maintain the current monitoring program to properly inform on avian
responses, and to fully document the recovery of waterbird populations, across the Lower Lakes. A
longer period of monitoring will also allow baseline abundances to be established during typical
conditions rather than the recent atypical conditions, and will aid in managing these wetlands in the
future.
The numbers of waterbirds counted in the Lower Lakes in January 2012 were almost double the
number counted in January 2011. With a few exceptions most species were more abundant in 2012
than 2011. Many of the species that showed increases in abundances in the Lower Lakes were fisheating species that had also increased in the Coorong (Paton & Bailey 2012). Amongst these were
the Pied, Little Pied (Phalacrocorax melanoleuca), Great and Little Black Cormorants, Great Egret
(Egretta alba), and Whiskered and Caspian (Hydroprogne caspia)Terns. The other species to show
substantial increases included the Australian Shelduck, Pacific Black Duck, Eurasian Coot, and
Straw-necked Ibis. In addition to being more abundant most of these species were also detected in
many more grid squares than in previous years (Table 3). This suggests that over time more of the
wetlands around the margins of the Lower Lakes were becoming suitable for waterbirds.
10
Only a few species declined in abundances relative to the previous year. These included Black
Swans, Chestnut Teals, Royal Spoonbills (Platalea regia) and Common Greenshanks (Tringa
nebularia). The declines in numbers of Common Greenshanks using the Lower Lakes are matched
by similar declines in the Coorong (Paton & Bailey 2012) and are of concern. Although Black Swans
and Royal Spoonbills also experienced reductions in abundances in the Lower Lakes, they both
expanded their distributions between January 2011 and January 2012 as indicated by marked
increases in the numbers of grid squares that these species occupied (Table 3). Both Black Swans
and Chestnut Teal were more abundant in the Coorong in January 2012, which may account for the
reduction of birds in the Lower Lakes. The opposite may have taken place with Australian
Shelducks, with large numbers shifting from the Coorong to the Lower Lakes in January 2012. The
numbers of Australian Shelduck counted in the Coorong in January 2012 were much lower by about
10,000 compared to the previous year, while those using the Lower Lakes were much higher by
about 8,000 in January 2012 compared with 2011 (Table 3, Paton & Bailey 2012). Since the
southern tip of Lake Albert is within a kilometre of the Coorong exchanges of waterbirds between
the Coorong and Lower Lakes are easily accomplished. In future, there may be merit in combining
the counts of waterbirds for the Coorong with those of the Lower Lakes and assessing changes in
abundances across the entire LLCMM Icon site rather than at the scale of the component wetland
systems.
Some care is required in interpreting the increases in the number of grid squares that were being
used by waterfowl in January 2012. In January 2012, 470 grid cells were visited compared with 370
in the year before. Many of the additional 1km x 1km grid squares that were added to the 2012
census were added to include small fringing or nearby wetlands or backwaters that carried water in
2012 but not 2011. Others included grid squares that contained paddocks where Australian
Shelduck were feeding on pastures. Most of these additional grid squares had only a small area of
wetland, as was the case for some of the grid squares around the shorelines of the lakes, so using
the number of grid squares in which a species was present as a measure of the area occupied by
that species is crude and likely to overestimate the actual area of habitat occupied. Furthermore,
given the larger number of grid squares scored for birds in 2012 some increase in the numbers of
grid squares occupied by different species would be expected. However, for three species the area
of occupation or number of grid squares occupied had increased substantially and by more than an
extra 100 grid squares between January 2011 and January 2012 (e.g. Little Pied Cormorant,
Eurasian Coot, and Great Egret; Table 3). A further eight species had increased their areas of
occupation by at least thirty grid squares. These species included the Australasian Darter (Anhinga
melanogaster), Pied Cormorant, Great Cormorant, Little Black Cormorant, Pacific Black Duck,
Purple Swamphen, Straw-necked Ibis and Caspian Tern. For these species, at least, there would
appear to have been a substantial expansion in their distributions between 2011 and 2012. Some of
the changes in distributions that have taken place over the last four years, and over the last two
years in particular, are shown for 12 species in Figures 1-4. These largely show species that have
marked increases in distribution. Previous reports (e.g. Paton & Bailey 2011b) have provided maps
showing changes in distributions of other species, including marked declines in distribution. As the
distributions of those species have not changed markedly since January 2011, updated maps for
these species incorporating the January 2012 data have not been produced.
In addition to increased abundances and wider distributions for a range of moderately common
species, a number of species that had not been detected since the surveys commenced four years
ago were detected in January 2012. These included Australasian Grebes (Tachybaptus
novaehollandiae), Freckled Ducks (Stictonetta naevosa), Pink-eared Ducks (Malachorhynchus
membranaceus), Spotless Crakes (Porzana tabuensis), Cattle Egrets (Ardea ibis), Glossy Ibis
(Plegadis falcinellis) and Australasian Bittern. Latham’s Snipe, Black-tailed Native Hens (Tribonyx
ventralis), Hoary-headed Grebes (Poliocephalus poliocephalus) and Australian Crake were also
seen in slightly higher numbers and or in more locations in January 2012 than in previous years.
These sightings of less frequently encountered species coupled with the general widespread
increases in waterbirds using the Lower Lakes suggests that a broad influx of waterbirds into the
region has taken place, presumably the birds coming from recently flooded wetlands elsewhere in
south-eastern and inland Australia. That many of the bird species detected do not breed in the
Lakes strengthens the case that the increased abundances recorded in January 2012 are due to
extensive movements of birds rather than extensive in situ breeding.
11
Two species of waterbirds that might have been expected to have shown similar increases, the
Yellow-billed (Platalea flavipes) and Royal Spoonbills, however were less abundant or remained in
low abundance. These species both wade in shallow water (water depths typically less than 30cm
deep) and may be disadvantaged when water levels in the Lower Lakes are maintained at high
levels. Alternatively these species may not be as mobile as other waterfowl or simply differ from
other species in the timing of their responses to changing conditions. Ultimately a greater
understanding of the movements of waterbirds between wetlands and what triggers these
movements, as well as the scales of these movements, will be needed to manage waterbird
populations effectively in the future.
An understanding is also needed of the habitat requirements of waterbirds using the Lower Lakes
and how the availability of suitable habitats is affected by changes in water levels. The current high
water levels in the Lower Lakes may disadvantage some wading species and small reductions in
water levels at appropriate times in the year (summer months) might increase opportunities for
some water birds that are currently in low numbers. Given this there may be merit in exploring
opportunities for varying the water levels in the Lower Lakes within some bounds. Advancing this
will require collecting detailed bathymetry and associated habitat features (sediment type,
submerged vegetation cover) as well as studies documenting habitat use and foraging efficiencies
of selected waterbirds around the shores of the Lower Lakes. Some of this has commenced (e.g.
Paton et al. 2011) and the monitoring program also contributes by documenting changes in
abundances and distributions through time but more information is required. Until that information is
available management regimes that maintain and improve waterbird populations in the Lower Lakes
cannot be determined.
12
Table 3. Distributions and abundances of waterbirds counted using the Lower Lakes in summer 2009 -2012. Distributions
are shown as the number of 1km x 1km grid cells (area occupied) in which the species was detected.
Species
Australian Pelican
Darter
Black-faced Cormorant
Pied Cormorant
Little Pied Cormorant
Great Cormorant
Little Black Cormorant
Australasian Grebe
Hoary-headed Grebe
Great Crested Grebe
Black Swan
Cape Barren Goose
Domestic Goose
Domestic Fowl
Australian Wood Duck
Australian Shelduck
Pacific Black Duck
Mallard (+ domestic duck)
Grey Teal
Chestnut Teal
Australasian Shoveler
Hardhead
Freckled Duck
Pink-eared Duck
Musk Duck
Blue-billed Duck
Australian Crake
Spotless Crake
Black-tailed Native-hen
Dusky Moorhen
Purple Swamphen
Eurasian Coot
Lewin’s Rail
White-faced Heron
White-necked Heron
Great Egret
Little Egret
Intermediate Egret
Cattle Egret
Nankeen Night Heron
Australasian Bittern
Glossy Ibis
Australian White Ibis
Straw-necked Ibis
Royal Spoonbill
Yellow-billed Spoonbill
Eastern Curlew
Common Greenshank
Marsh Sandpiper
Wood Sandpiper
Sharp-tailed Sandpiper
Red-necked Stint
Curlew Sandpiper
small wader (unidentified)
Masked Lapwing
Banded Lapwing
Latham's Snipe
Red-kneed Dotterel
Red-capped Plover
2009
4259
2
35
1342
166
2081
107
Abundance
2010
2011
4460
2996
5
2
1
982
1717
96
82
6124
4997
1298
826
12
896
1692
2
24
2791
1215
13
12022
1187
13
10854
654
5
2
15787
2003
16
13857
302
17
44
2
4
1
2
1
13
9
252
95
104
16
32
3308
94
1
65
2
217
4166
1303
36
6
9
14296
1684
1
804
430
8
1
12
1
30
47
39
1
222
105
4
2
6
463
181
396
55
5
146
9238
23727
66
998
178
3
1641
178
387
341
58
2
219
6
9
13250
31138
1026
2500
800
424
4
20
1164
1195
532
201
17
29
2012
2698
124
3
3955
397
9371
2091
71
36
108
1334
2207
27
54
21973
5751
10
5780
111
10
108
9
250
1
2
28
2
133
44
446
3650
2009
169
2
3
39
19
56
14
6
50
58
1
5
63
44
1
105
63
2
76
14
1
1
128
56
2
73
7
2
2
1
2
1
1
1
1
5
2
132
51
388
5
38
5
8
8
1
61
1073
2586
125
21
4
13
6
6
15
61
1
24
2
7
179
50
4
2
4
105
111
1
22
35
2
1
7
1
9
13
3
1
63
37
4
2
3
52
11
11
6
1
36
32
100
456
301
1
83
85
11
309
447
134
9
1
2
7
77
2
13
Area occupied
2010 2011
178
233
1
2
1
26
122
13
21
80
270
17
37
1
130
34
5
22
14
1
39
2
2
98
98
21
2
121
10
1
2
119
138
65
29
11
14
2012
265
46
1
218
147
309
121
11
10
50
209
58
3
9
148
199
4
76
16
5
23
3
6
1
1
6
1
17
16
82
165
74
194
5
1
2
1
6
118
109
36
9
2
9
2
2
2
18
10
1
75
72
1
1
4
11
2
Species
Lesser Sand Plover
Black-fronted Dotterel
Black-winged Stilt
Banded Stilt
Red-necked Avocet
Silver Gull
Whiskered Tern
Caspian Tern
Gull-billed Tern
Crested Tern
Fairy Tern
White-breasted Sea-Eagle
Osprey
Whistling Kite
Swamp Harrier
Clamorous Reed-Warbler
Golden-headed Cisticola
Little Grassbird
TOTAL
2009
2
1
197
96
141
3743
3536
283
2
529
1
1
4
10
1
15
81,480
Abundance
2010
2011
2012
86
2
7
324
3484
3744
236
2819
80
186
264
29
10
2747
4348
458
313
4
1
309
11
3
39,875
1
2
28
9
14
74,739
327
1
112,265
2009
1
1
22
8
6
165
88
71
1
72
1
1
2
4
1
5
269
Area occupied
2010 2011
2012
9
1
1
7
163
116
69
159
6
63
23
2
1
151
335
131
79
3
1
96
2
2
370
1
2
17
6
8
470
63
1
310
ACKNOWLEDGMENTS
This report was commissioned by the Department for Water, through The Living Murray initiative
(Operations and Major Programs Division) with funding provided by the Murray-Darling Basin
Authority. Adrienne Frears provided administrative support. Able assistance with counting
waterbirds was provided by Phil Northeast, Lynn Pedler, Fiona Paton, Alastair Wood, Lydia Paton,
Joel Allan, Andrew Barker, Tom Hunt, Tom Bradley, Emily Hoffmann and Sally Scrivens as well as a
team of able support volunteers. The Department for Environment and Natural Resources provided
research permits and access to protected areas, with the census conducted under animal ethics
approval from the University of Adelaide. Many property owners kindly provided access to
shorelines through their properties.
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Murray-Darling Basin Commission, 2006. The Lower Lakes, Coorong and Murray Mouth Icon Site
environmental management plan 2006-2007. Murray-Darling Basin Commission, Canberra.
Paton DC 2010. At the End of the River: The Coorong and Lower Lakes. ATF Press, Hindmarsh.
Paton DC, Bailey CP. 2010a. Condition Monitoring of the Lower Lakes, Coorong and Murray Mouth
Icon Site: Waterbirds using the Coorong and Murray Estuary 2010. (University of Adelaide,
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Icon Site: Waterbirds using the Coorong and Murray Estuary 2011. (University of Adelaide,
Adelaide)
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Paton DC, Bailey CP 2011b. Condition Monitoring of the Lower Lakes, Coorong and Murray Mouth
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Paton DC, Bailey CP, Northeast PJ 2011. Waterbird responses to Goolwa Channel water-level
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Paton DC, Rogers DJ 2009 Condition monitoring of indicator bird species in the Lower Lakes,
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15
Darter
Pied Cormorant
Little Pied Cormorant
2009
2010
2011
2012
Figure 1. Changes in distribution for Darter, Pied Cormorant
16 and Little Pied Cormorant in the
Lower Lakes for 2009 to 2012.
Great Crested Grebe
Great Egret
Straw-necked Ibis
2009
2010
2011
2012
Figure 2. Changes in distribution for Great Crested Grebe,
17Great Egret and Straw-necked Ibis
in the Lower Lakes for 2009 to 2012.
Black Swan
Pacific Black Duck
Eurasian Coot
2009
2010
2011
2012
Figure 3. Changes in distribution for Black Swan, Pacific18
Black Duck and Eurasian Coot in the
Lower Lakes for 2009 to 2012.
Purple Swamphen
Caspian Tern
Whiskered Tern
2009
2010
2011
2012
Figure 4. Changes in distribution for Purple Swamphen,19
Caspian Tern and Whiskered Tern in
the Lower Lakes for 2009 to 2012.
20