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James N. IanelliAlaska Fisheries Science CenterSeattle, WA
Trends in North Pacific Cod and Pollock
Trends in North Pacific Cod and Pollock
Outline
Alaska pollock:Gulf of AlaskaEastern Bering SeaBogoslof and Aleutian Islands regionRussian zone
• Recent US-Russian negotiations
Pacific cod
0
1
2
3
4
5
6
7
8
1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 2001
Cat
ch in
Mill
ion
t North America
AsiaAsia
Donut Hole
World pollock catch 1981-2002
Pollock Fishery Areas
GOA
Kamchatka
EBS
NBS
WBSSea of Okhotsk
Aleutians
Est. 2002 Pollock Catch by area
Total: ~2.57 million t
E. Bering Sea
58%
W.Kamch.
11%
Others
4%
Okhotsk
11%GOA
2%
W.Bering
14%
Conservation Strategies Key Quota management acronyms
• ABC’s (acceptable biological catch)
• TAC’s (total allowable catch)
• OFL’s (overfishing levels)
ABCTAC Catch
GOA
Gulf of Alaska
Gulf of Alaska pollock age 3+ biomass trend
0
2,000
4,000
1970 1974 1978 1982 1986 1990 1994 1998 2002
Thousands of tons
2002 survey estimate low—but 1999 yearclass well above average
Gulf of Alaska summaryWinter 2002 survey estimates low…
2001 TAC 105.8 thousand tons,
2002 TAC 58.25 thousand tons,
2003 likely to be between 40-60 thousand tons
1999 year class well above average
Steller sea-lions likely to affect TAC-setting in this
area
Eastern Bering Sea Pollock
GOA
Kamchatka
EBS
NBS
WBSSea of Okhotsk
Aleutians
Eastern Bering Sea Pollock Biomass trends
Highly dependent on recruitment
• Both highly variable
Three surveys in 2002:
• Limited shelf acoustic survey in winter
• Summer trawl and acoustic surveys
Issues :
Extent of straddling stock
Steller sea lions
Fishery Characteristics for 2002
Within-year production (E. Bering Sea)k-tons
0
250
500
25-Jan 05-Feb 15-Feb 25-Feb 07-Mar 17-Mar 27-Mar 06-Apr 16-Apr 26-Apr
Cu
mu
lati
ve
po
lloc
k c
atc
h
199719981999200020012002
2002 Winter fishery distribution
Catch size distributionJan-June July - Dec
20 25 30 35 40 45 50 55 60 65 70
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
Length (cm)20 25 30 35 40 45 50 55 60 65 70
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
Length (cm)
2002 survey data…
Pollock density from bottom-trawl survey
Bottom temperature and pollock density…
Bottom trawl survey biomass estimates
0.0
2.0
4.0
6.0
8.0
10.0
1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 2001
Year
Mill
ion
s o
f to
ns
Bottom-trawl survey abundance at age
2000
Age
2001
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
20021992
1992
1992
2000
Age
2001
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
2002
1996
1996
1996 2000
Age
2001
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
20021992
1992
1992
2000
Age
2001
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
2002
1996
1996
1996 2000
Age
2001
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
20021992
1992
1992
2000
Age
2001
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
2002
1996
1996
1996
Results from integrated model Recruitment estimates…
Year class index
0
25,000
50,000
75,000
1963 1965 1967 1969 1971 1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 2001
Nu
mb
ers
at
ag
e 1
EBS Biomass trend
0
5,000
10,000
15,000
1975 1980 1985 1990 1995 2000
Th
ou
san
ds
of
ton
s
Change in age-composition estimates
2001
2002
2003
9897
96
9594 93
92
0
3,000
6,000
9,000
12,000
3 4 5 6 7 8 9
Last year's assessment
Current assessment
9998
97
96
9594 93
0
3,000
6,000
9,000
12,000
3 4 5 6 7 8 9
0
3,000
6,000
3Age
0
3,000
6,000
3Age
2000
1999 1998 19971996
1995 1994
0
3,000
6,000
9,000
12,000
3 4 5 6 7 8 9
199519961997199819992000
2001
0
3,000
6,000
9,000
12,000
3 4 5 6 7 8 9Age
Age
Steller sea lion population update
2002 est.
0
10,000
20,000
30,000
1990 1995 2000
Sea Lion issues NEPA, ESA compliance problems by NMFS
1. Species still listed as “endangered”
2. Action that may affect recovery of species
identified (fishing)
3. Consultation may be required for the Gulf of Alaska
pollock (and other) fisheries
Ecosystem issues Committee reviewing North Pacific TAC-setting
process relative to ecosystem needs
• Report due to Council in December
• May look to Antarctic system (CCAMLR) for meeting
perceived ecosystem requirements
Environmental factors increasing in application to
all fish-stock assessments
• Long-term and short-term productivity
Other issues
Marine Stewardship Council
Final announcement delayed to early next year
• Eastern Bering Sea pollock apparently passed ok
Essential Fish Habitat requirements
Pollock fishery important since mid-water
Cooperative acoustic data collection established
To monitor pollock abundance in Critical Habitat
Acoustic return…
Relative sA: Survey vs Fishery
Aleutian Islands Region
GOA
Kamchatka
EBS
NBS
WBSSea of Okhotsk
Aleutians
Aleutian Islands Region
Pollock stock surveyed poorly
Bottom trawl gear
Every 2 years
2002 estimate ~360,000 tons (> double estimate from 1990s)
Pollock as bycatch only since 1999 for sea lion concerns
Last year quota expectation for 2002 ~25,000 tons
• NOT! Set to bycatch only again…
Pollock prognosis for 2003: bycatch
Aleutian Islands recent surveys
Basin or “Donut Hole” Region
Central Bering Sea Convention
Some experimental fishing/surveys Poor catch rates
Bogoslov survey index of this stock still low Estimates of over 1 million tons may trigger an International
Basin fishery
Recruitment patterns appear to have changed
Non contiguous parties wish for a quota
• Closures since 1992
• Recovery not apparent
Bogoslov survey estimates
Millio
ns o
f to
ns
0
0.5
1
1.5
2
2.5
1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002
Donut-hole(Central Bering Sea)
Stock indicator
Russian Zone
Catch, Survey information
Central Bering Sea consultation
GOA
Kamchatka
EBS
NBS
WBSSea of Okhotsk
Aleutians
Russian stock condition:Navarin basin biomass estimates
0
50,000
100,000
150,000
200,000
250,000
1996 1997 1998 1999 2000 2001 2002
Hydroacoustic
Bottom trawl
Russian stock condition: Western Bering Sea biomass trend
Thousands of tons age 2+
0
500
1,000
1,500
2,000
2,500
1970 1980 1990 2000
Russian stock conditionSpawning stock size in Sea of
OkhotskThousands of tons
0
500
1,000
1,500
2,000
2,500
3,000
1998 1999 2000 2001 2002 2003
US-Russian bilateral meetings“The disputed agreement of 1990 was signed by Eduard Shevardnadze, then USSR Minister of Foreign Affairs, and James Baker, US Secretary of State, for the USA to overtake an approximate 50,000 square kilometres of sea from Russia. The strip abounds in fish. Russia's State Fishing Committee experts estimate the annual catch of Pacific pollock alone at 200,000 tons. The agreement cost Russia an approximate 2.8 million tons of fish at more than US$1.4 billion, complain experts.”
Sept 2002 Moscow ICC meeting report
“… The U.S. delegation made clear that the United States is not prepared to review or renegotiate the maritime boundary treaty, though the U.S. was prepared to discuss other areas of cooperation.”
Observed catch
Russian quota breakdown for 2002Total 930,000 tons
N Okhotsk
Sea
19%
W Sakhalin
7%
N Bering
39%
W Bering
1%
W
Kamchatka
27%
E Sakhalin
1%
Kuriles-
Kamchatka
6%
Pollock Summary Gulf of Alaska
2001 summer and 2002 winter survey estimates low Good sign of 1999 year class (impact expected by 2004) TAC prognosis again about ~50 kt
Aleutian Islands Stocks Increasing Steller sea lion issues close to resolution TAC may be re-instated ~35,000 t
Aleutian Basin - Bogoslof: Fishery continues to be unlikely in near future
Eastern Bering Sea Stock outlook on track in near term, ABC expected to decline 1996 year-class not as prevalent in recent surveys 2003 TAC likely to be around 1,480 kt
Russia: Sea of Okhotsk and other areas may be undergoing species shift
• Herring Quota reductions may increase illegal fishing
Pacific Cod Abundance trends
0
1,000
2,000
3,000
4,000
1978
1980
1982
1984
1986
1988
1990
1992
1994
1996
1998
2000
2002
West BeringNorth BeringGulf of AlaskaEast Bering
Sea lion issues also concern Pacific cod
P. cod and Atka mackerel considered with pollock as
essential for sea lions
Issue was the level of concentrations during spawning
seasons within Critical Habitat
Due to the higher complexity, management problems more
difficult
• Multiple gear-types and fishing sectors
Pacific Cod Outlook 2002
Gulf of Alaska projected ABC/TAC stable or slight
increase
Eastern Bering Sea ABC/TAC likely to be flat
• Strong year classes evident but survey estimate lower
Russian Pacific cod considered stable and small
EBS Pacific cod biomass trend
0
400,000
800,000
1,200,000
1,600,000
1978 1983 1988 1993 1998 2003
Survey observation
Model Estimate