Gulf of Alaska Groundfish Plan Team Sandra Lowe and James N. Ianelli Gulf of Alaska Groundfish Plan Team Update on groundfish stock trends for the Gulf

Gulf of Alaska Groundfish Plan Team

Sandra Lowe and

James N. Ianelli


Update on groundfish stock trends

for the Gulf of Alaska

Additional GOA Plan Team MembersDiana Stram NPFMC

Bill Bechtol ADFG

Tory O’Connell ADFG

Mike Ruccio ADFG

Lew Halderson UAF

Kathy Kuletz USFWS

Bill Clark IPHC

Farron Wallace WDF

Jeff Fujioka AFSC

Sarah Gaichas AFSC

Jon Heifetz AFSC

Tom Pearson AKR

Beth Sinclair NMML


Summary by biomass


Projected biomass by species~4 million tons total

Sablefi sh

5%

Rockfi sh

19%

Pollock

17%

Flatfi sh

16%

Arrowtooth

32%

P. Cod

11%


Summary by ABC’s


Projected ABC’s by species 414,820 tons total

Pollock

13%

Flatfi sh

25%

Arrowtooth

38%

Atka mackerel

0% P. Cod

13%

Sablefi sh

3%

Rockfi sh

8%


ABC SummarySpecies 2002 2003 ChangePollock 58,250 54,350 down 3,900 (7%)Pacific cod 57,600 52,800 down 4,800 (8%)Flatfish 63,900 63,690 down 210 (<1%)

Flathead sole 22,690 41,390 up 18,700 (82%)

Arrowtooth 146,260 155,140 up 8,880 (6%)

Sablefish 12,820 13,110 up 290 (2%)

Pacific ocean perch 13,190 13,660 up 470 (4%)

Northern rockfish 4,980 5,530 up 550 (11%)Shortraker/Rougheye 1,620 1,620 same -Other slope rockfish 5,040 5,050 up 10 -

Pelagic shelf rockfish 5,490 5,490 same -Demersal shelf rockfish 350 390 up 40 (11%)Thornyheads 1,990 2,000 up 10 (1%)Atka mackerel 600 600 same -

Total 394,780 414,820 up 20,040 (5%)


Pollock

0

1,000

2,000

3,000

4,000

0

100

200

300CatchRecruitmentBiomass

Bio

mass

or

Recr

uit

men

tC

atch


Pollock

0

1,000

2,000

3,000

4,000

1962

1965

1968

1971

1974

1977

1980

1983

1986

1989

1992

1995

1998

2001

Catch

Biomass

Bio

mass


Fit to winter EIT surveys

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1990 1992 1994 1996 1998 2000 2002 2004

Year

Bio

ma

ss (

mill

ion

t)

Model predictedSurvey estimates


NMFS bottom trawl survey (1984-2001)

0.0

0.4

0.8

1.2

1.6

2.0

1980 1985 1990 1995 2000

Bio

ma

ss (

mill

ion

t)

Model predicted

Survey estimates

0.00

0.05

0.10

0.15

0.20

0.25

0.30

0.35

1988 1990 1992 1994 1996 1998 2000 2002

ADFG crab/groundfish trawl survey (1989-2002)

0.00

0.05

0.10

0.15

0.20

0.25

0.30

0.35

1988 1990 1992 1994 1996 1998 2000 2002

Year

Bio

ma

ss (

mill

ion

t)

Model predicted

Survey estimates

Fit to trawl surveys…


0.0

0.2

0.4

0.6

0.8

1.0

1960 1965 1970 1975 1980 1985 1990 1995 2000

Year

Mill

ion

t

B40%

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

1961 1964 1967 1970 1973 1976 1979 1982 1985 1988 1991 1994 1997 2000

Spawning biomass

Recruitment

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

1961 1964 1967 1970 1973 1976 1979 1982 1985 1988 1991 1994 1997 2000

Year

Rec

ruitm

ent

(Bill

ions

)

Recruitment

Pollockmodelresults


Added pollock conservation measures

Model selected

Survey catchability assumption fixed at 1.0

Updated maturity-at-age used

Assuming average 1999 yearclass

Constant-buffer scheme used

No adjustments to the 2002 Shelikof Strait survey

estimate


Shelf break


Pollock 2003 ABCAverage 1999

year class1999 year class

as estimated

Author's adjustment 49,600

102,000Maximum permissible

59,200

86,000


20% 30% 40% 50%

Percent of unfished

2002 Prob(SSB<B20) = 0.21

2003, Prob(SSB<B20) = 0.02

2004, Prob(SSB<B20) = 0.00


Pollock Spawning biomass

Spawning biomass (1,000’s tons)

2003 = 177

B40% = 240

B20% = 120



Flathead sole 22,690 41,390 up 18,700 (82%)

Arrowtooth 146,260 155,140 up 8,880 (6%)

Sablefish 12,820 13,110 up 290 (2%)

POP 13,190 13,660 up 470 (4%)



Total 394,780 414,820 up 20,040 (5%)


Pacific cod

Notes:

Selectivity estimated over three stanzas:

1978-86, 1987-99, & 2000 to the present

Risk-averse ratio applied to F40%

Steller sea lion prey species

Last survey in 2001 (next in 2003)


Pacific cod

0

300

600

900

1978 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002

Bio

mas

s (t

hous

ands

of m

t)

0

100

200

300 Recruitm

ent (millions age 3

fish)

Catch Recruitment Age 3+ Biomass


Pacific cod

Female spawning biomass (tons)

2003 = 88,300

B40%= 90,300

B20%= 45,150



Flathead sole 22,690 41,390 up 18,700 (82%)

Arrowtooth 146,260 155,140 up 8,880 (6%)

Sablefish 12,820 13,110 up 290 (2%)




Total 394,780 414,820 up 20,040 (5%)


Flathead sole (new assessment)

0

50

100

150

200

250

300

1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002

Age

3+ B

iom

ass

(tho

usan

ds m

t)

0

2

4

Catch (thousand

s mt)

Biomass

Catch


Flathead sole

Female spawning biomass (tons)

2003 = 93,500

B40%= 38,100


Arrowtooth flounder

0

0.5

1

1.5

2

1977 1980 1983 1986 1989 1992 1995 1998 2001

Age

3+ B

iom

ass

(mill

ions

mt)

0

0.2

0.4

0.6

Recruitm

ent (billions age 3

fish)

Recruitment

Biomass


Flatfish 2003 ABC’s260,220 tons total

Shallow water

19%

Arrowtooth

59%

Flathead sole

16%

Deep water

2%

Rex sole

4%



Flathead sole 22,690 41,390 up 18,700 (82%)

Arrowtooth 146,260 155,140 up 8,880 (6%)

Sablefish 12,820 13,110 up 290 (2%)




Total 394,780 414,820 up 20,040 (5%)


Sablefish Notes

Survey abundance increased ~6% from 2001 estimate

Status “moderate” and increased from recent low

levels (nearly at B40% level)

Authors proposed ABC recommendation based on

estimates of probability of future stock sizes

Plan Team agreed with ABC (in general) but not the

method


Sablefish

0

200

400

600

1960 1964 1968 1972 1976 1980 1984 1988 1992 1996 2000

Age

4+ B

iom

ass

(1000s

mt)

0

30

60

90

120 Recruitm

ent (age 2)

Age 2 Recruitment

Biomass age 4+


Sablefish spawning biomass


2003 = 210

B40%= 216



Flathead sole 22,690 41,390 up 18,700 (82%)

Arrowtooth 146,260 155,140 up 8,880 (6%)

Sablefish 12,820 13,110 up 290 (2%)




Total 394,780 414,820 up 20,040 (5%)


Pacific ocean perch

0

100

200

300

1977 1980 1983 1986 1989 1992 1995 1998 2001

Thou

sand

s

Bio

mas

s

0

60

120

180

Thou

sand

s

Recruitm

ent age 2

Catch

Recruitment

Biomass


Northern rockfish

0

20

40

60

80

100

120

140

160

180

1977 1980 1983 1986 1989 1992 1995 1998 2001

Thou

sand

sA

ge 6

+Bio

mas

s

0

10

20

30

40

50

60

70

80 Thousand

sRecruitm

ent age 2

CatchRecruitmentBiomass


POP & northern rockfish biomass

0

50

100

150

200

250

300

350

1977 1980 1983 1986 1989 1992 1995 1998 2001

Thou

sand

sA

ge 6

+Bio

mas

s

POP

Biomass


Slope Rockfish 2003 ABC’s25,860 tons total

POP

53%

Northern

21%

Other slope

20%

Shortraker

/Rougheye

7%


Rockfish spawning biomass


POP:

• 2003 = 112

• B40% = 105

Northern:

• 2003 = 43

• B40% = 25


Pelagic shelf rockfish: biomass

0

20

40

60

80

1987 1989 1991 1993 1995 1997 1999 2001

Bio

mas

s (1

000s

mt)

Combined

Dusky avg

Widow & yellowtail avg

Dusky, widow, & yellowtail


Pelagic shelf rockfish: catch

0

3

6

9

1987 1989 1991 1993 1995 1997 1999 2001 2003

metr

ic t

ons

(1,0

00's

) CatchTACABC

Dusky, widow, & yellowtail


Demersal shelf rockfish

0

5

10

15

20

25

30

35

1990 1992 1994 1996 1998 2000 2002

Bio

mas

s (1

000s

mt)

0

0.2

0.4

0.6

0.8

1

1.2

Catch (1

000s m

t)

BiomassCatchTACABC


Thornyheads

0

30

60

90

1977 1980 1983 1986 1989 1992 1995 1998 2001

Bio

mas

s or

Rec

ruit

men

t

(1000s

mt

or fi

sh)

0

3

6

9

Catch

(1000s m

t)

Catch

Age 5 recruitment

Age 5+Biomass


Thornyhead spawning biomass


2003 = 22.8

B40% = 15.8


Rockfish Stock Status

0

40

80

120

Thousands

Pacific ocean

perch

Northern

rockfish

Shortspine

thornyheads

B40%

SpBiom 2003


Rockfish Stock StatusSpawning biomass / BMSY

100%

125%

150%

175%

Pacific ocean perch Northern rockfish Shortspine

thornyheads


ABC summary relative to maximum permissible

0

20

40

60

Thousands

Poll

Pcod

Sab

lefi

sh

POP

NRF

SR/R

E

Slo

peRF

She

lfRF

SS

T

Dem

Shl

fRF

Atk

a

ABC

Max Permissible

Documents

Gulf of Alaska Groundfish Plan Team Sandra Lowe and James N. Ianelli Gulf of Alaska Groundfish Plan Team Update on groundfish stock trends for the Gulf