Managing for Overall Value Ecosystem Based
Management
March 7, 2014
Southwest Alaska Municipal Conference
Anchorage, AK
The recommendations and general content presented do not necessarily represent the views or official position of the Department of Commerce,
National Oceanic and Atmospheric Administration, National Marine Fisheries Service
Why Ecosystem Science?
•
Built into the Magnuson – Stevens fishery conservation and management act
– Sec. 406 FISHERIES SYSTEM RESEARCH
(f) REGIONAL ECOSYSTEM RESEARCH
(1) STUDY. – “…the Secretary (Dept. of Commerce), in consultation with
the Councils, shall undertake and complete a study on the state of the
science for advancing the concepts and integration of ecosystem
considerations in regional fishery management. The study should
build upon the recommendations of the advisory panel and include” –
(A) “Recommendations for scientific data, information and
technology requirements for understanding ecosystem
processes,…”
(B) “…stakeholder participation”
(C) “…recommendations for ..understanding ecosystem processes ..
to account for effects of environmental variation on fish stocks
and fisheries”
(D) “describe…Council efforts to implement ecosystem
approaches…”
http://spo.nmfs.noaa.gov/tm/TM96Web.pdf
Report
Recommendation
Highlights
•Maintain current stock assessment surveys.
Sablefish example
•Seek to account for the effects of environmental variation on
fish stocks and fisheries.
Ecosystem Chapter provided to Council
•Sustain ecosystem observations, process oriented research,
and integrative modeling.
Bering Sea Walleye Pollock Example
NOAA Fisheries
Ecosystem Science
Jason Link, Ph.D
Senior Scientist
Ecosystem Management
Ihde, T, and H. Townsend. 2013. Interview with Jason Link: champion for ecosystem
science and management. Fisheries 38(8):363 - 369
Stock assessments by region (2013)
Alaska
31
11
Northwest
Pacific Islands
3
Northeast
4
6
5
Southwest
8
Southeast and
Caribbean
U.S. Department of Commerce
| National Oceanic and
Atmospheric Administration |
What is stock assessment?
Biomass = Birth + Growth - Catch - Death
We collect data from the fishery and from surveys to determine:
Birth (recruitment), growth, and death (natural mortality) from which
we get an optimum level of catch (fishing mortality)
Optimum catch is based on Maximum Sustainable Yield (MSY)
Assessment and management’s job is to determine the level of risk
we are willing to take to maximize the return from the fishery
A high growth stock produces a high rate of return, with high volatility
A low growth stock produces a low rate of return, with low volatility
Dana Hanselman
Stock Assessments
Groundfish Trawl Data
(age, size, CPUE)
Other Fishery Data
Sablefish
Walleye Pollock
Mathematical
Models
Fish Biomass &
Mortality Estimates
Recommendations to the
Fishery Management Council
(Stock Assessment and
Fishery Evaluation)
Reports
Harvest Guidelines/ Regulatory
Measures
Gulf of Alaska Sablefish
Gulf of Alaska Sablefish Survey
Stock Assessment and Fishery
Evaluation Reports
Gulf of Alaska
Sablefish
http://www.afsc.noaa.gov/refm/stocks/assessments.htm
500
400
300
200
100
Survey
Cooperative longline
Domestic longline
0
Relative Population Number
Western GOA, Aleutian Islands, and Bering Sea
1980
1985
1990
1995
2000
2005
2010
2000
2005
2010
2000
2005
2010
200
150
100
50
Survey
Cooperative longline
Domestic longline
0
Relative Population Number
Central
YearGOA
1980
1985
1990
1995
100
50
Survey
Cooperative longline
Domestic longline
0
Relative Population Number
150
Eastern
YearGOA
1980
1985
1990
1995
2000
1997
2008
Seek to account for the effects of
environmental variation on fish stocks
and fisheries.
http://www.afsc.noaa.gov/REFM/Docs/2013/ecosystem.pdf
Pg. 148
Ecosystem indicators and
sablefish recruitment
Modeling age-2 sablefish abundance
50
Shared rearing habitat for juvenile
salmon and age-0 and age-1 sablefish
Indicators: age-0 sablefish stage
August chlorophyll a (+)
August sea temperature (+)
Juvenile pink salmon abundance (+)
2nd order autoregressive (+)
Yasumiishi, Shotwell, Hanselman, Orsi, Fergusson in prep
30
20
10
-10
0
Age-2 sablefish (millions)
40
Observed
Fitted
Residuals
2002
2004
2006
2008
2010
2012
Year
Figure 5. Joint linear regression and time series error model describing age-2 sablefish abundance as a function of
chlorophyll a and sea temperature during the age-0 phase, juvenile pink salmon estimated from adult returns,
and a 2nd order autoregression process (R2 = 0.97, F = 50.5, P-value = 0.00008, BIC = 73).
Bering Sea
Walleye Pollock
Bering Sea Walleye Pollock
Bering Sea Walleye Pollock
Sustain ecosystem observations,
process oriented research, and
integrative modeling
At what life history stage does
climate have the greatest impact
on fish recruitment?
21
Hypotheses
Climate and Ecosystem Productivity Hypothesis
H1: Climate change and variability have predictable affects
on the bottom-up and top-down mechanisms which
regulate fish recruitment.
Critical size and period Hypothesis
H2: The effects of climate and ecosystem function on fish
recruitment are most evident during 2 critical periods:
1) early to juvenile stage when mortality is a function of
growth rate;
2) the first winter when mortality is a function of size and
energetic status obtained during previous summer and fall.
Fisheries – Oceanographic Surveys
Northern Bering
Sea and Chukchi
Sea Assessment
Southern Bering
Sea Assessment
40° Longitude
18° Latitude
Gulf of Alaska
Assessment
3
Spring Temperature Anomaly
2
Bering Sea
Sea Surface Temperature Anomaly
Poor Recruitment
1
Better Recruitment
0
-1
-2
-3
1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010
Zooplankton (Fish Food)
Euphausiids
180
large
small
12000
160
10000
140
120
8000
100
6000
80
60
4000
40
2000
20
0
0
2002 2003 2004 2005 2006 2007 2008 2009 2010 2011
Small zooplankton (No. m-3)
Large zooplankton (No. m-3)
Large Copepods
Small Copepods
Age 0 Pollock Diet
BASIS Fish Diets; Theragra chalcogramma; 30 - 97 mm
100
Theragra chalcogramma
Euphausiids
Ammodytes hexapterus
Mallotus villosus
Fish
Shrimp
Limacina helicina
Crab Larvae
Larvaceans
Small Copepods
Large Copepods
Chaetognaths
Themisto spp.
Small meroplankton
Others
Prey Items (%)
80
60
40
20
0
2003
Coyle et al. 2011
2004
2005
2006
Year
2007
2008
2009
Age 0 Pollock
Fitness
kJ/g wet wt.
6.5
Warm
Cold
5.5
Critical value
4.5
3.5
2.5
2002
2004
2006
2008
2010
2012
Age 1
Relationship to Recruitment
Age 0
Oscillating Control Hypothesis
Bering Sea Walleye Pollock
Bottom up
Climate connection
to ecosystem
Top down
Ecosystem connection
to fish recruitment
Hunt et al. 2011
Integrated Model
Goal: Understand the impact of climate variability
and change on ocean conditions and birth,
growth, and death of commercial fish.
Trophic Dynamics
Thank You!
Climate Scenario
Example
From IPCC climate models
BEST-BSIERP Bering Sea
Bering Sea Project underscores commitment
to research supporting the ecosystem approach
to fisheries management
● $52 M funding
● 24,205 person-days of fieldwork completed
● 100 principal investigators
● 2007 – 2010 Field Work
● 2011 – 2013 Synthesis
bsierp.nprb.org
Project
● 119 publications to date
bsierp.nprb.org
0.2
0.5
-0.2
0.0
-0.6
-0.5
Effect on pollock survival
Ecosystem Indicator:
Average Summer
Sea Temperature
7.5
8.0
8.5
9.0
9.5
SST at age-0
Coyle et al. 2011
10.5
7.5
8.0
8.5
9.0
9.5
10.5
SST at age-1
36
What is stock assessment?
Example 1: The dividend stock
Rougheye rockfish:
Maximum age: ~200 years
Maximum sustainable harvest rate: 3%
Change in annual quota: +-2%
Example 2: The growth stock
Walleye pollock:
Maximum age: ~ 20 years
Maximum sustainable harvest rate: ~30%
Change in annual quota: +/- 20%
Dana Hanselman