Transcript Ecosystem Considerations in Fisheries Management

Status of the Southeastern Bering Sea
– Upper Trophic Level and Aggregate Indicators
Linking Ecosystem-Based
Management Goals with
Ecosystem Research
Fisheries
And The
Environment
I. ECOSYSTEM ASSESSMENT
Objectives for Ecosystem Protection:
1. Maintain predator-prey relationships
a.
b.
c.
d.
pelagic forage availability
spatial/temporal conc. of fishery impact on forage fish
removals of top predators
introduction of non-native species
CLIMATE and FISHING
2. Maintain diversity
a. species diversity
b. functional (trophic, structural habitat) diversity
c. genetic diversity
3. Maintain energy flow and balance
a. human-induced energy redirection
b. system impacts attributable to energy removal
Bering Sea/Aleutian Islands
195
BS
level oflevel
catch
BSTrophic
Trophic
195
Ice Cover
Index
Ice Cover
Index
AIAI
Trophic
level oflevel
catch
Trophic
Surface
Winter
Air
Temp.
Surf. Winter Air Temp.
Total salmon
catch
Total salmon
catch
PDO
PDO
Herring
recruits
Herring
recruits
MaySST
SST
May
Productivity
COMUCOMU
Productivity
AOI
AOI
Atka(R/S)
(R/S)
Atka
TotalCPUE
CPUE
Total
BS Diversity
BS Diversity
Jellyfish
biomass
Jellyfish
biomass
AK Plaice(R/S)
(R/S)
AK Plaice
Cod(R/S)
(R/S)
Cod
Pollock(R/S)
(R/S)
Pollock
BS Richness
BS Richness
Total crab
biomass
Total crab
biomass
BLKI Productivity
BLKI Productivity
TBMUTBMU
Productivity
Productivity
RLKI Productivity
RLKI Productivity
YFS(R/S)
(R/S)
YFS
POP
POP(R/S)
(R/S)
Northerns
(R/S)
Northerns
(R/S)
GTGT(R/S)
(R/S)
ATF
ATF(R/S)
(R/S)
sole(R/S)
(R/S)
RockRock
sole
FHS(R/S)
(R/S)
FHS
Summer
Bottom
Summer
BottomTemp.
Temp.
Hook Line
and Line
Effort
Hook and
Effort
AI Bottom
Trawl
Duration
AI Bottom
Trawl
Duration
BS Bottom
Trawl
Duration
BS Bottom
Trawl
Duration
BSPelagic
Duration
BS Pelagic
TrawlTrawl
Duration
2.6>X>1.6
1.6>X>0.5
0.5>X>-0.5
-0.5>X>-1.6
-1.6>X>-2.7
no data
190
197
197
197
195
197
198
198
198
197
197
196
198
198
197
197
197
196
196
197
197
197
197
197
198
199
199
199
199
2000
1995
1990
1985
1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004
1980
X>2.6
190
1975
Legend
191
1970
Year
196
Objectives for Ecosystem Protection:
1. Maintain predator-prey relationships by examining:
a.
b.
c.
d.
pelagic forage availability
spatial/temporal conc. of fishery impact on forage fish
removals of top predators
introduction of non-native species
2. Maintain diversity by examining:
a. species diversity
b. functional (trophic, structural habitat) diversity
c. genetic diversity
3. Maintain energy flow and balance by examining:
a. human-induced energy redirection
b. system impacts attributable to energy removal
Objectives for Ecosystem Protection:
1. Maintain predator-prey relationships by examining:
a. pelagic forage availability
Significance threshold: changes outside natural variability
for prey relative to predator demands
Indicators:
-NMFS bottom trawl survey catches of forage fish
-BASIS surveys -age-0 pollock (BS)
-ADFG herring
-Groundfish trends
-Groundfish fishery bycatch amounts
-Bristol Bay sockeye salmon
120
100
80
2004
2006
1998
2000
2002
1992
1994
1996
1986
1988
1990
1982
1984
30
1982
1984
1986
1988
1990
1992
1994
1996
1998
2000
2002
2004
2006
FORAGE –NMFS (Lauth)
Eulachon
20
10
0
Capelin
60
40
20
0
Abundance
Age-4 recruits
2003
1998
1993
1988
1983
1978
Abundance & Recruits (millions fish)
Biomass
Catch
400
2000
200
1000
0
0
Biomass and Catch (1,000s mt)
FORAGE –Togiak Herring (F. West)
FORAGE – Juvenile sockeye and pollock
-BASIS (Eisner et al.)
2000
Juvenile
Sockeye
Counts
Age-0
Pollock
Counts
2001
2002
2003
2004
Other
Ugashik
Naknek
Kvichak
Egegik
70
60
50
40
30
20
2001
1996
1991
1986
1981
1976
1971
1966
0
1961
10
1956
Catch plus escapement (millions)
Bristol Bay Sockeye Salmon (L. Fair)
B.Sea
Groundfish
1976/77 shift
1988/89 shift
0.20
YFS
0.20
0.30
ATF
0.10
0.00
-0.10
-0.10
1996
1990
1984
1978
1972
-0.20
0.20
ROCK SOLE
0.60
0.40
R/S Anomalies
0.00
0.20
COD
NORTHERNS
0.10
0.20
0.00
0.00
-0.20
-0.20
-0.40
0.40
FH SOLE
-0.10
0.40
0.20
0.20
0.00
0.00
-0.20
-0.20
0.30
GT
AI ATKA
0.20
0.10
0.00
-0.10
0.40
POP
0.00
0.20
-0.50
002
996
990
984
978
972
966
960
-0.40
2002
1996
1990
1984
-0.20
1978
1960
0.00
2002
1996
1990
1984
1978
1972
AK PLAICE
0.50
1966
1.00
1960
2002
1996
1990
1984
1978
1972
1966
1960
-0.40
1972
1966
1960
2002
-0.20
-0.20
POLLOCK
0.20
0.10
0.00
0.00
Other shift
1966
0.40
0 .5
1980
1980
2000
1998
1996
1994
1992
1990
1988
1986
1984
2002
2000
1998
1996
1994
1992
1990
1988
1986
1984
1982
1978
1978
0 .5
1 .0
- 0 .5
0 .0
0 .5
1 .0
Bering Sea
1982
1976
1976
0 .0
Recruitment Index
- 0 .5
Recruitment Index
- 1 .0
1974
1 .0
1974
0 .5
1972
0 .0
1970
- 0 .5
1970
1972
1974
1976
1978
1980
1982
1984
1986
1988
1990
1992
1994
1996
1998
2000
2002
1972
- 1 .0
Survival Rate Index
0 .0
1970
1970
1972
1974
1976
1978
1980
1982
1984
1986
1988
1990
1992
1994
1996
1998
2000
2002
- 0 .5
Survival Rate Index
Groundfish – Combined Std. Indices of Recruitment and
Survival (Mueter)
Gulf of Alaska
Biological Response to Climate
Flatfish Distribution-(Spencer)
Objectives for Ecosystem Protection:
1. Maintain predator-prey relationships by examining:
a.
b.
c.
d.
pelagic forage availability
spatial/temporal conc. of fishery impact on forage fish
removals of top predators
introduction of non-native species
2. Maintain diversity by examining:
a. species diversity
b. functional (trophic, structural habitat) diversity
c. genetic diversity
3. Maintain energy flow and balance by examining:
a. human-induced energy redirection
b. system impacts attributable to energy removal
Objectives for Ecosystem Protection:
1. Maintain predator-prey relationships by examining:
a.
b.
c.
d.
pelagic forage availability
spatial/temporal conc. of fishery impact on forage fish
removals of top predators
introduction of non-native species
Significance threshold: catches high enough
to cause biomass of top predator(s) to fall
2. Maintain diversity
examining:
belowby
min.
biol. acceptable limits
a. species diversity
b. functional (trophic,
structural habitat) diversity
Indicators:
c. genetic diversity -Trophic level of the catch
-Population status of top predators
3. Maintain energy flow
andtakes
balance
examining:
-Fishing
of topby
predators
a. human-induced energy
redirection
-Seabird
incidental take
b. system impacts attributable to energy removal
4
2000
1990
2000
1990
1980
1970
0.0
1980
1
0
1.0
1970
2
2.0
1960
1,000
FIB Index
3
3.0
Trophic level catch
2,000
1960
Total catch (1000 t)
TOP PREDATORS – Trophic level of the catch
FIB= index that shows a decline
in TL only when catches do not
increase as expected
TOP PREDATORS
•Northern fur seal pup production continued
decline (Sinclair et al.)
325
50
Pups born (1,000's)
St. Paul
275
St. George
40
225
30
175
20
125
73
78
83
88
93
98
03
10
73
78
83
88
93
98
03
TOP PREDATORS – Seabirds (Fitzgerald et al.)
Seabird Breeding Chronology
Seabird Population Trends
>3days earlier than average
12
=within 3days of average
Frequency
>3 days later than average
8
6
4
2
0
N.BS/Chuk. SE BS
SW BS
16
GOA
SEAK
Negative trend
No discernable trend
Positive trend
N.BS/Chuk. SE BS
Seabird Productivity Levels
>20% below average
14
Frequency
Frequency
10
18
16
14
12
10
8
6
4
2
0
Within 20% of average
12
>20% above average
10
8
6
4
2
0
N.BS/Chuk. SE BS
SW BS
GOA
SEAK
SW BS
GOA
SEAK
Effort
BSAI
Incidental take
250,000
0.16
200,000
0.12
150,000
0.08
100,000
0.04
50,000
2003
2002
2001
2000
1999
1998
1997
1996
1995
0
1994
0
0.1
(per 1,000 hooks)
0.2
Incidental take rate
300,000
1993
Fishing Effort (in 1,000's of hooks)
TOP PREDATORS
Seabird Incidental Take (Fitzgerald et al.)
PREDATOR -Bering Sea Jellyfish (Walters)
400,000
350,000
250,000
200,000
150,000
100,000
50,000
2004
2002
2000
1998
1996
1994
1992
1990
1988
1986
1984
1982
0
1980
Biomass (t)
300,000
Objectives for Ecosystem Protection:
1. Maintain predator-prey relationships by examining:
a.
b.
c.
d.
pelagic forage availability
spatial/temporal conc. of fishery impact on forage fish
removals of top predators
introduction of non-native species
2. Maintain diversity by examining:
a. species diversity
b. functional (trophic, structural habitat) diversity
c. genetic diversity
3. Maintain energy flow and balance by examining:
a. human-induced energy redirection
b. system impacts attributable to energy removal
Objectives for Ecosystem Protection:
 Maintain predator-prey relationships by examining:




pelagic forage availability
spatial/temporal conc. of fishery impact on forage fish
removals of top predators
introduction of non-native species
2. Maintain diversity by examining:
a. species diversity
Significance threshold: catch high enough to cause biomass to
fall below or be kept from recovering from min. biol. acceptable
limits
Indicators:
-Status of protected and managed stocks relative to thresholds
-Species richness and diversity
-Areas closed to fishing
-Pop’n trends -other nontarget species from surveys (eg. eelpouts)
-Bycatch trends of sensitive species lacking population estimates
Ecosystem Mngt Info. –Area closures (Coon)
SPECIES DIVERSITY –
and
diversity (Mueter)
12
1985
1990
1995
2000
Richness= number of species per haul
2.0
1.8
1.6
Species per haul
13
14
index
Shannon-Wiener
Species per haul
15
Species richness
1985
1990
1995
2000
Diversity= function of number of
species and relative abundance per
haul
Objectives for Ecosystem Protection:
1. Maintain predator-prey relationships by examining:
a.
b.
c.
d.
pelagic forage availability
spatial/temporal conc. of fishery impact on forage fish
removals of top predators
introduction of non-native species
2. Maintain diversity by examining:
a. species diversity
b. functional (trophic, structural habitat) diversity
c. genetic diversity
3. Maintain energy flow and balance by examining:
a. human-induced energy redirection
b. system impacts attributable to energy removal
Objectives for Ecosystem Protection:
2. Maintain diversity by examining:
b. Functional (trophic and structural habitat) diversity
Significance threshold: catch high enough to cause change
outside observed natural variability
Indicators:
-guild or size diversity
-bottom gear effort
-HAPC biota bycatch
-habitat research:
Distribution of deep-water corals in AI
Seafloor mapping and colonization studies
Effects of trawling on benthic habitat
Growth and recruitment of coral
Spatial and temporal patterns in BS invertebrate assemblages
Demersal fish community size spectrum, 1982-2002
(Bartkiw et al.)
a
a
Through time:
12
fewer small individuals and
11
10
more large individuals
9
8
7
ln (N +1)
6
1986
1984
Year
4.42
1982
4.23
3.98
ln (length midpoint +1)
3.65
3.16
2
1
0
1988
1990
1992
1994
1996
1998
2000
2002
5
4
3
Observed Bottom Trawl duration (24 hour days)
SPECIES DIVERSITY- Bottom trawl effort (Coon)
3500
3000
2500
2000
1500
BS
GOA
AI
1000
500
0
1990
1992
1994
1996
1998
2000
2002
2004
0
300
10
200
5
100
Sea anemone
2000
0
1982
1984
1986
1988
1990
1992
1994
1996
1998
2000
2002
2004
2006
Seapens
1982
1984
1986
1988
1990
1992
1994
1996
1998
2000
2002
2004
15
1982
1984
1986
1988
1990
1992
1994
1996
1998
2000
2002
2004
2006
FUNCTIONAL DIVERSITY – HAPC Biota (Lauth)
Sponge
1500
1000
500
0
Objectives for Ecosystem Protection:
1. Maintain predator-prey relationships by examining:
a.
b.
c.
d.
pelagic forage availability
spatial/temporal conc. of fishery impact on forage fish
removals of top predators
introduction of non-native species
2. Maintain diversity by examining:
a. species diversity
b. functional (trophic, structural habitat) diversity
c. genetic diversity
3. Maintain energy flow and balance by examining:
a. human-induced energy redirection
b. system impacts attributable to energy removal
Objectives for Ecosystem Protection:
3. Maintain energy flow and balance by examining:
a. human-induced energy redirection
Significance threshold: long-term changes in system biomass,
respiration, production, energy-cycling due to discards and offal
Indicators:
-Prohibited species bycatch amounts
-Nontarget catch and discards
-Groundfish discards
-Trends in scavenger species
ENERGY REDIRECTION
Prohibited Catch (Hiatt and Terry)
400
BAIRDI CRAB
OTHER TANNER CRAB
10000
CHINOOK SALMON
OTHER SALMON
No. fish (1000s)
No. of crab (1000s)
15000
300
200
5000
100
0
8000
RED KING CRAB
OTHER KING CRAB
HALIBUT MORTALITY
HERRING BYCATCH
Metric tons
6000
200
4000
100
2004
2003
2002
2001
2000
1999
1998
1997
1996
1995
0
1994
2004
2003
2002
2001
2000
1999
1998
1997
1996
0
1995
2000
1994
No. of crab (1000s)
0
300
ENERGY REDIRECTION
Discards (Hiatt and Terry)
Bering Sea/Aleutian Islands
Tonnage discarded
Percent discarded
16%
200
8%
Improved retention
regulations
2004
2003
2002
2001
2000
1999
1998
0%
1997
0
1996
4%
1995
100
Discard rate
12%
1994
Discards (1000 t)
300
Objectives for Ecosystem Protection:
1. Maintain predator-prey relationships by examining:
a.
b.
c.
d.
pelagic forage availability
spatial/temporal conc. of fishery impact on forage fish
removals of top predators
introduction of non-native species
2. Maintain diversity by examining:
a. species diversity
b. functional (trophic, structural habitat) diversity
c. genetic diversity
3. Maintain energy flow and balance by examining:
a. human-induced energy redirection
b. system impacts attributable to energy removal
Objectives for Ecosystem Protection:
3. Maintain energy flow and balance by examining:
b. system impacts attributable to energy removal
Significance threshold: long-term changes in system biomass,
respiration, production, energy-cycling due to fishery removals
of energy
Indicators:
-Total catch relative to production
ENERGY REMOVAL -Total Catch
2,500,000
Eastern Bering Sea Catch
2,000,000
Catch (mt)
Other species
Crab
1,500,000
Flatfish
Pacific herring
1,000,000
Rockfish
Pacific cod
500,000
Walleye pollock
1954 1959 1964 1969 1974 1979 1984 1989 1994 1999
Year
Bering Sea
Gulf of Alaska
1400
300
1200
250
1000
200
800
150
600
400
100
200
50
0
0
GOA ASP (1000 mt)
7000
6000
5000
4000
3000
2000
1000
0
-1000
1978
1980
1982
1984
1986
1988
1990
1992
1994
1996
1998
2000
2002
2004
BS ASP (1000 mt)
ASP (1000 mt)
ENERGY REMOVAL– ASP (Mueter)
Management Goals
Groundfish FMP Goals
• Prevent overfishing
• Promote sustainable fisheries and communities
• Preserve food web
• Manage incidental catch and reduce bycatch and
waste
• Avoid impacts to seabirds and marine mammals
• Reduce and avoid impacts to habitat
• Promote equitable and efficient use of fishery
resources
• Increase Alaska native consultation
• Improve data quality, monitoring and
enforcement
Ecosystem Assessment
Objectives
• Maintain predator-prey
relationships
• Maintain diversity
• Maintain energy flow
and balance
Groundfish FMP
Goals
Ecosystem
Considerations Indices
Prevent overfishing
Status of stocks, annual surplus productivity
Promote sustainable fisheries and
communities
Fishing overcapacity programs
Preserve food web
Pelagic forage availability, spatial/temporal conc. of
fishery impact on forage fish, removals of top
predators, introduction of non-native species
Manage incidental catch and reduce
bycatch and waste
Prohibited species, discards, bycatch, scavenger
population trends
Avoid impacts to seabirds and marine
mammals
Seabird and mammal incidental take, population
abundance, productivity, and chronology trends
Reduce and avoid impacts to habitat
EFH research, effects of fishing gear on habitat
research
Promote equitable and efficient use of
fishery resources
Fishing overcapacity programs, groundfish fleet
composition
Increase Alaska native consultation
ANTEK of climate regimes
Improve data quality, monitoring and
enforcement
Executive Summary
• CLIMATE
– North Pacific in uncertain state
– BS continues to warm, less sea ice and earlier retreat
• BIOLOGY
–
–
–
–
–
–
–
BS summer zooplankton biomass: low 2000-2004
BS jellyfish biomass: low 2000-2004
Warming trend may affect flatfish distribution
Most seabirds show no discernable population trend
2002 seabird breeding chronology was early
2004 N. fur seal pups born continued to decline
ASP in BS decreased from 1978-2004
• FISHERY EFFECTS
– 2003 and 2004 increases in herring and other salmon
bycatch
– 2003 seabird incidental take rate same as 2002
Website: Geoff Lang
http://access.afsc.noaa.gov/reem/ecoweb/index.cfm
Summary
• No noted significant adverse impacts of fishing on
the ecosystem (relating to predator/prey interactions, energy
flow/removal, or diversity).
• There are gaps in understanding the system-level
impacts and spatial/temporal effects of fishing on
community structure and prey availability.
• Future: incorporate predictions from multispecies
models.
• Need research, validation of models, and models
focused on understanding spatial processes, and
improvements in monitoring systems
• A range of possible climate scenarios and plausible
effects on recruitment should be entertained.