# Presentation: 193309

## Update on groundfish stock trends for the Gulf of Alaska

- Sandra Lowe
- and James N. Ianelli
- Gulf of Alaska Groundfish
- Plan Team

**Update on groundfish stock trends ****for the Gulf of Alaska**

- _Additional GOA Plan Team Members_
- Diana 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

## Summary by ABC’s

## Projected ABC’s by species 414,820 tons total

## ABC Summary

**Species**

**2002**

**2003**

**Change**

- Pollock

-         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

- Biomass or Recruitment

- Catch

**Notes:**
The pollock slide shows average recruitment (818 million fish) for
2001 from the 1999 year class, rather than the estimated recruitment
value of 3.29 billion.  Average recruitment from the 1999 year class was
assumed in the projections to derive ABC, etc.

The Plan Team's pollock ABC has been reduced by the 1,700 mt Prince
William Sound GHL (groundfish harvest level).  This was taken out off
the top from the Shumagin, Chirikof, Kodiak and West Yakutat areas.

## Pollock

- Biomass

**Notes:**
The pollock slide shows average recruitment (818 million fish) for
2001 from the 1999 year class, rather than the estimated recruitment
value of 3.29 billion.  Average recruitment from the 1999 year class was
assumed in the projections to derive ABC, etc.

The Plan Team's pollock ABC has been reduced by the 1,700 mt Prince
William Sound GHL (groundfish harvest level).  This was taken out off
the top from the Shumagin, Chirikof, Kodiak and West Yakutat areas.

## Fit to winter EIT surveys

## Fit to trawl surveys...

- Fit to trawl surveys...

## Pollockmodelresults

**Spawning biomass**

**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 ABC

- Average 1999 year class

- 1999 year class
- as estimated

- Author's adjustment

- 49,600

- 102,000

- Maximum
- permissible

- 59,200

- 86,000

## Percent of unfished

- 20%

- 30%

- 40%

- 50%

- 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

## ABC Summary

**Species**

**2002**

**2003**

**Change**

- Pollock

-         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%)

- POP

-          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%)

## Pacific cod

**Notes:**
- Selectivity estimated over three stanzas:1978-86, 1987-99, & 2000 to the present
- Risk-averse ratio applied to *F**40%*
- Steller sea lion prey species
- Last survey in 2001 (next in 2003)

## Pacific cod

## Pacific cod

**Female spawning biomass (tons)**
- 2003 = 	88,300
- B40%	=	90,300
- B20%	=	45,150

## ABC Summary

**Species**

**2002**

**2003**

**Change**

- Pollock

-         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%)

## Flathead sole (new assessment)

## Flathead sole

**Female spawning biomass (tons)**
- 2003 = 	93,500
- B40%	=	38,100

## Arrowtooth flounder

## Flatfish 2003 ABC’s260,220 tons total

## ABC Summary

**Species**

**2002**

**2003**

**Change**

- Pollock

-         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%)

## Sablefish

**Notes**
- Survey abundance increased ~6% from 2001 estimate
- Status “moderate” and increased from recent low levels (nearly at *B**40%* 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

## Sablefish spawning biomass

**Spawning biomass (1,000’s tons)**
- 2003 = 	210
- B40%	=	216

## ABC Summary

**Species**

**2002**

**2003**

**Change**

- Pollock

-         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%)

## Pacific ocean perch

## Northern rockfish

## POP & northern rockfish biomass

## Slope Rockfish 2003 ABC’s25,860 tons total

## Rockfish spawning biomass

**Spawning biomass (1,000’s tons)**
- POP:
- 2003 = 	112
- B40%	=	105
- Northern:
- 2003 = 	43
- B40%	=	25

## Pelagic shelf rockfish: biomass

- Dusky, widow, & yellowtail

**Notes:**
2)  Pelagic shelf rockfish - formally the dusky rockfish M was applied
to a 3 survey average biomass to come up with the complex ABC.  Now the
assessment appropriately partitions out dusky rockfish and considers
them in Tier 4, versus the other components - widow and yellowtail
rockfish, which are in Tier 5.  ABCs are computed separately for dusky
(F=M x ave. biomass) and for widow and yellowtail combined (0.75M x ave.
biomass).  The slide now shows the dusky ave. biomass and the widow and
yellowtail ave. biomass

## Pelagic shelf rockfish: catch

- Dusky, widow, & yellowtail

**Notes:**
2)  Pelagic shelf rockfish - formally the dusky rockfish M was applied
to a 3 survey average biomass to come up with the complex ABC.  Now the
assessment appropriately partitions out dusky rockfish and considers
them in Tier 4, versus the other components - widow and yellowtail
rockfish, which are in Tier 5.  ABCs are computed separately for dusky
(F=M x ave. biomass) and for widow and yellowtail combined (0.75M x ave.
biomass).  The slide now shows the dusky ave. biomass and the widow and
yellowtail ave. biomass

## Demersal shelf rockfish

## Thornyheads

## Thornyhead spawning biomass

**Spawning biomass (1,000’s tons)**
- 2003 	= 	22.8
- B40%	=	15.8

## Rockfish Stock Status

## Rockfish Stock StatusSpawning biomass / BMSY

## ABC summary relative to maximum permissible