Download The Scientific Research Requirements of an Ecosystem

Research Requirements of an
Ecosystem Approach to
Fisheries
A Scotian Shelf Case Study
Bob O'Boyle, Mike Sinclair & Tana Worcester
Bedford Institute of Oceanography
Canada
Greenland
Eastern Scotian Shelf
60
2G
2
2H
55
2J
200 mile
limit
Canada
Newfoundland
Region
3K
Quebec Region
50
Atlantic
Ocean
4S 4R
Gulf
Region
4T
Newfoundland
3P
45
No
6B
Browns Bank
Georges
4X
Bank
5 4
6
75
3
3M
3O
4V
3N
5Z
6D
6C
35
Grand Banks
Banquereau
Bank
5Y
Cape Cod
6A
a
coti
4W
U.S.A.
40
S
va
3L
70
6E
65
60
6F
6G
55
6H
50
45
Figure 1: Canada's East Coast showing the Divisions used by the North
Atlantic Fisheries Organization (NAFO).
Scotia-Fundy Region highlighted.
Atlantic Canadian 'lab'
since 1998
40
Approach

Types of Issues



Issues from number of sources, e.g.





Impact of fishery on ecosystem
Impact of ecosystem on fishery
Challenge of
interpreting
causality &
cumulative effects
ESSIM Management Plan
Ecosystem Status Report for ESSIM Area
Paper prepared for SCOR 2004 Paris Symposium
Scotia-Fundy Fishing Industry Roundtable
Classified issues using Canada's nationally established
conservation objectives



Biodiversity
Productivity
Habitat
Approach (cont'd)

For each objective, management question posed &
associated research identified

Assessed probability that research can resolve
issue in 3 - 5 years


Is it tractable?
Judged scope of research effort (who can do?)



Institute (BIO & St. Andrew's Biological Station)
Atlantic Coast (Newfoundland Shelf to Gulf of Maine)
Global (International collaboration)
Biodiversity Issues
• Ecosystem level
• Species level
• Population level
Can fisheries management & industry
respond to large scale ecosystem
changes?
 Investigate
biogeographic characteristics of
fish/invertebrate communities & how these
respond to circulation/mixing

Revisit 1990s East Coast of North America
Strategic Assessment Project (ECNASAP)
Tractability: High
Scale: Coast
Species Scale
Distributions
Identified transitions
in bottom
communities
consistent with
circulation & mixing
patterns
Movement in
transition zones in
response to North
Atlantic Oscillation
(NAO)
Mahon et. al. 1998
When NAO
Positive
60
55
Tendency for
Northern
Transition Zone
to move South
&
Southern
Transition Zones
to move North
Bottom
Community
Transition
Zones
50
Newfoundland
45
40
Are these patterns
Predictable?
35
75
70
65
60
55
50
45
40
What can be done to recover species at risk ?
 Survivorship
of leatherback
turtles released from large
pelagic longlines
 Juvenile
mortality & location of
porbeagle pupping grounds

Prediction of life history
characteristics of data poor
species
Tractability: High
Scale: Institute
Tractability: Medium
Scale: Coast
Tractability: Medium
Scale: Institute
How should species-at-risk be monitored?
 Investigate whether bottom trawl surveys
provide reliable indicators of abundance

Cusk hard to sample but show dramatic decline
in abundance; is this real or due to contraction
to preferred habitat?
Survey
CPUE
Issues with other
species
(e.g. Barndoor
Skate)
Tractability: Medium
Scale: Coast
Do present management practices allow
accurate discard & by-catch estimates?

Impact of discarding on non-commercial species
Tractability: Low
Scale: Institute

Estimation of discard & by-catch in ESS fisheries

May 2006 workshop uncovered significant data issues
Tractability: Medium
Scale: Institute
Also Productivity Issue
Should fisheries management be concerned
about population substructure?
Prior to 1984, ESS cod composed of
spring & fall spawning components
1979-84
1988-92
Determine if re-establishment of spring
spawning component necessary for
recovery?
Similar questions for
other species
E.g. What is link
between ESS and Bay
of Fundy Herring?
Tractability: Low
Scale: Institute
Productivity Issues
• Trophic Processes
• Population Processes
What are management
implications of systematic
removal of large fish on
ecosystem functioning?
+
-
+
-
 ESS
ecosystem
regulation


bottom - up or top - down?
Frank et al (2003)
suggests top - down
Tractability: Low
Scale: Global
+
-
+
-
 Determine
Survey Z
source & impact of high M on cod
Similar pattern
seen in other
depleted finfish
(e.g. wolffish &
skate)
Are these
species in
predator traps?
Tractability: Low
Scale: Coast
 Role

of grey seals
Determine what population processes (e.g.,
density - dependent) regulate seals
Pups
Recent evidence
for drop in r
Predicted
Observed
Tractability: Medium
Scale: Coast
Roughly 700,000t of prey consumed each
year compared to 6,000t 40 yr ago

Investigate food requirements &
consumption estimates of apex
predators (seals, sea birds, etc)
Tractability: Low
Scale: Institute
ESS Cod consumed using 3 different model assumptions
What is minimum Spawning Stock Biomass for
Scotian Shelf stocks?

Determine long-term changes in SSB

ESS Cod good example of Pauly's 'Shifting Baseline
Syndrome'
MSY
Recent Assessments
Tractability: Low
Scale: Institute
Have current harvest practices caused growth
reduction in gadoids?

Determine relative roles of environment
& genetic selection on haddock growth
Scotian Shelf
NE Atlantic
4.0
4.0
5Z
4X bof
4X wss
4VW
3.5
3.0
3.0
2.5
2.5
2.0
2.0
1.5
1.5
1.0
1.0
0.5
0.5
0.0
1970
NE Arctic
North Sea
Faroes
Icelandic
3.5
0.0
1975
1980
1985
1990
1995
2000
2005
1970
1975
Weight (kg) at Age 7
1980
1985
1990
1995
2000
Tractability: Low
Scale: Institute
Habitat Issues
• Spatial processes
• Climate change impacts
Are fishery closures & gear restrictions
adequate to protect benthic habitat?
Determine
if benthic community spatial
patterns can be predicted from geological,
oceanographic & biological observations
Determine
proportion of each benthic habitat
type that needs to be protected

Sensitivity of benthic communities
Tractability: Medium
Scale: Global
Influence of geology, oceanography &
biology on life history traits
Scope for Growth
Low Productivity
(Adverse)
Food Availability
Water temperature
Variability in temperature
Oxygen Saturation
Stratification
Wave height/period
Lowest
Risk to
Impact
De p th
G ra in size
C u rre n t
Highest
Risk
to
Impact
Stable
Disturbed
Disturbance
High Productivity
(Benign)
Areas of Potentially
Higher Sensitivity

Determine relationship between size & location of
protected areas & benthic community conservation
Current Closures
Fishery
Biodiversity
Tractability: Low
Scale: Global
Can impacts of climate change
on habitat be predicted?
 Mechanism
whereby climate change
influences ESS oceanography

Impacts on benthic & pelagic habitat
 Implications
of North Atlantic Oscillation
(NAO)
Tractability: Low
Scale: Coast
NAO
Winter
Anomaly
NAO Winter Anomaly
20
10
0
-10
-20
-30
1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010
• Linkage of Scotian Shelf
with larger North Atlantic
atmospheric system
• Different response to
NAO north & south of
Halifax
• Periodic? Predictable?
1970 - 2003 bottom
C0 differences
(neg - pos anomaly)
Prioritization
 Needs
to occur at scale of problem
(BIO, Northwest Atlantic, International
Community)

Influenced by tractability
 Tractability?


Most low - medium
All significant to EAF & will require longer
term research
Emergent Research Issues
requiring international collaboration
 Link
biodiversity to productivity & resilience
 Ecosystem
regulation (bottom - up & top -
down)
 Link
between habitat type & sensitivity
SCOR
WG?
 Spatial
scales of connectivity between
benthic communities
Thank You!
Outline

EAF - related issues specific to Eastern Scotian
Shelf

Will not discuss industry - industry issues
• E.g. fisheries & petroleum conflicts

Research priorities for EAF in this area for next 3
- 5 years

Broader research implications of regional
experience
Sustainability
of
Human
Usage
Economic
Dimension
Conservation
of
Species &
Habitats
Social &
Cultural
Dimension
Environmental
Dimension
Conserve
Ecosystem
Components
(Biodiversity)
Conserve
Component's
Role
(Productivity)
DFO
Conservation
Objectives
Conserve
Physical/Chemica
l Properties
Maintain
Communities
Maintain
Primary
Productivity
Conserve
Critical
Landscape/
Bottomscape
Maintain
Species
Maintain
Trophic
Structure
Conserve
Water
Column
Properties
Maintain
Populations
Maintain
Population
Generation
Time
Conserve
Water
Quality
Conserve
Biota
Quality
Traditional
Fisheries
Management
Intent is for
Fisheries Management
to address all objectives

Determine if snow crab &
shrimp are sustainable
populations or Gulf
extension during cold
conditions.
Tractability: Low
Scale: Institute
 Determine what is controlling the
invasion rate of Codium.
Tractability: Low
Scale: Institute
Barndoor Skate & Surveys
Size is Important
Trawl
Survey
?
Immature
Skate
Mature
Skate
Longline
Survey
Longline Survey samples all size groups
Trawl Survey samples predominantly immature skate
Monitoring species at risk requires
consistent time series of Spawners
Does management need to consider
impact of climate change?
 Trends
in fish recruitment in relation to
climate change

Link between timing of spring phytoplankton
bloom & ESS haddock recruitment
Tractability: Low
Scale: Coast
Also Productivity Issue
 Are
current seal consumption
estimates accurate?

Issues with stomach samples
• Biased towards small prey?
• Fishermen observe cod belly bites

Issues with fatty acid analysis
• Reproducible?
Tractability: Medium
Scale: Institute