Scup ( Stenotomus chrysops ): 2012 Update

Scup (Stenotomus chrysops): 2012 Update

• Managed as a unit stock from New England to Cape Hatteras, NC

• Maximum size & age fish in NEFSC SVs and fishery samples:SV: 1973 - 41 cm FL at age 14; 1976, 1978 - 38 cm at age 14; 2001 - 41 cm FL at age 9Comm land: 1970s - 45-46 cm FL at ages 8-10, 40 cm at

14

• 50% mature at age 2; M = 0.20

• Commercial trawl fishery; recreational rod and reel fishery• Comm. landings ~50%; Comm. discards ~30%• Rec. landings ~20%; Rec. discards <1%

• NEFSC SVs peaked in late 1970s, early 2000s• Comm landings (and probably total catch) peaked in 1955-1965

ScupTotal Commercial Landings and NEFSC Spring Biomass Index

Year

1940 1950 1960 1970 1980 1990 2000 2010

Met

ric T

ons

(live

wei

ght)

0

5000

10000

15000

20000

25000

NEF

SC S

prin

g (k

g pe

r tow

)

0

2

4

6

8

10

12

14

Total commercial landings and NEFSC Survey Spring biomass index.

Assessment history Scup (Stenotomus chrysops)

• First analytical assessment: 1995 SAW 19 - ADAPT VPAHigh CVs on estimated Ns; uncertain comm discards (constant ratio for 1984-1988; high variability in rates for 1989-1994)

• 1997 SAW 25: “Poor quality of input data” (Discard estimation, landings length sampling); assessment downgraded to “exploratory VPA” to provide general trends

• 1998 SAW 27: “Exploratory VPA” and ASPIC production model rejected as basis for management; index approach adopted; NEFSC, MADMF, RIDFW, CTDEP, NJBMF available

• NEFSC Spring used for Biomass BRP = SSBMSY Threshold;

SAW 19 YPR Fmax = FMSY

Assessment historyScup (Stenotomus chrysops)

• 1998 SAW 27: Recommended move to index-based assessment– 1955-1965: Sustainable commercial landings ~20,000 mt – stock at

BMSY– Late 1970s: closest NEFSC SV peak – commercial landings at

about one-half of 1955-1965 level – stock at one-half BMSY • NEFSC Spring used for Biomass BRP = SSBMSY Threshold =

1977-1979 mean = 2.77 SSB kg/tow; SAW 19 YPR Fmax = FMSY = 0.26

• SAW27 Recommendations adopted in FMP Amendment 12 as basis for BRPs

• Amendment 14 formalized proxy BMSY = 2*2.77 = 5.54 SSBkg/tow

Assessment historyScup (Stenotomus chrysops)

• 2000 SAW 31: Index-based for biomass (NEFSC Spring SBBkg/tow) and F (catch curves); F => 1.0 for ages 0-3

• 2002 SAW 35: Index-based; Relative Exploitation Index (landings/index) developed to help set quotas; F = unknown

• 2003-2008: MAFMC Monitoring Committee updates of NEFSC Spring SSB Index basis for biomass status; No reliable F estimates – use REI to monitor F

Data Poor Stocks Working Group (DPSWG) 2008Scup (Stenotomus chrysops)

• ASAP model: sufficient as basis for stock assessment

• Non-parametric BRPs: SSB/R, Y/R to get Fmax, F40% (M= 0.20)

• R from 1984-2007 (period with fishery and SV age data)

• MCMC for year T+1 Ns for AGEPRO

• AGEPRO for SSBMSY, 2009 TAC

• Considered multiple configurations and model settings to evaluate sensitivity and uncertainty

Data Poor Stocks Working GroupScup (Stenotomus chrysops): December 2008

• Scup not overfished, overfishing not occurring in 2007

• Improved R and low F, SSB increased to 119,000 mt in 2007, F decreased to 0.05 in 2007, relative to:

• SSBMSY = SSB40% = 92,044 mt• FMSY = F40% = 0.177 (M = 0.2)• MSY = 16,161 mt total catch; 13,134 mt landings; 3,027 mt discards

Data Poor Stocks Working GroupScup (Stenotomus chrysops): December 2008

• DPSWG 2008 Peer Review Panel Advice:

• "...rapid increases in quota to meet the revised MSY would be unwarranted given uncertainties in recruitments. A more gradual increase in quotas is a preferred approach reflective of the uncertainty in the model estimates and stock status.“

• TAC 2009: 7,049 mt = 15.54 mlbs• TAL 2009: 5,071 mt = 11.18 mlbs


• Status for 2008: Not Overfished, Not Overfishing• SSB2008 = 188,000 mt; • F2008 = 0.042 (fully recruited ages 2-7+); • R2008 = 192.4 million age 0 fish

• TAC for 2010: 7,752 mt (17.090 mlbs)• TAL for 2010: 6,400 mt (14.110 mlbs)• Increase of 10% over 2009 TAC


• Status for 2009: Not Overfished, Not Overfishing• SSB2009 = 155,000 mt; • F2009 = 0.043 (fully recruited ages 2-7+); • R2009 = 140 million age 0 fish

• ACL for 2011: 14,479 mt (31.920 mlbs)• TAL for 2011: 12,020 mt (26.500 mlbs)• Increase of 87% over 2010 TAC


• Status for 2010: Not Overfished, Not Overfishing• SSB2010 = 186,000 mt; • F2010 = 0.040 (fully recruited ages 2-7+); • R2010 = 44 million age 0 fish

• ACL for 2012: 18,543 mt (40.881 mlbs)• TAL for 2012: 16,749 mt (36.925 mlbs)• Increase of 163% (2.6 x) over 2009 TAC (ACT)


• Update Landings and Discards through 2011• Update Survey Indices through 2011• Age compositions use 2011 ALKs• Retain DPSWG 2008 Assessment ASAP

configuration and run model• Update status for 2011• Assume 2012 TAL (landings quota) is caught• Make projection to determine 2013 OFL

1984

1985

1986

1987

1988

1989

1990

1991

1992

1993

1994

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

2007

2008

2009

2010

2011

0

100

200

300

400

500

600

700

800

0

500

1000

1500

2000

2500

3000

3500

4000

Scup Fishery Sampling Intensity

Comm Land Comm Disc Rec Land Rec Disc

Year

Met

ric to

ns p

er 1

00 le

ngth

s

Rec

Disc

Met

ric to

ns p

er 1

00 le

ngth

s

Scup Total Catch Mean Weights at Age

Year1983 1986 1989 1992 1995 1998 2001 2004 2007 2010 2013

Mea

n w

eigh

t (kg

)

0.0

0.5

1.0

1.5

2.0Ages 0 - Age 7+

1960 1970 1980 1990 2000 20100

2

4

6

8

10

12

14

16

NEFSC Biomass Indices

Spring Fall Winter

Year

Surv

ey k

g/to

w

1960 1970 1980 1990 2000 20100

100

200

300

400

500

600

0

200

400

600

800

1000

1200

Scup Age 0 Abundance Indices

NEFSC CTDEP NYDEC VIMS RIDFW Trap

Year

Surv

ey N

/tow

RIDF

W T

rap

N/hr

1975 1980 1985 1990 1995 2000 2005 20100

5

10

15

20

25

30

35

40

45 MADMF Biomass Indices

Spring Fall

Year

Surv

ey k

g/to

w

1980 1985 1990 1995 2000 2005 20100

5

10

15

20

25

30

35

0

2

4

6

8

10

12

14

RIDFW Indices

Fall Spring Coop Trap

Year

Fall

Surv

ey k

g/to

w

Sprin

g Su

rvey

kg/

tow

; Tra

p N

/trap

/hr

1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 20100

50

100

150

200

250

300

350

400

450

URIGSO Abundance Index

URIGSO

Year

URIG

SO N

/tow

1980 1985 1990 1995 2000 2005 20100

5

10

15

20

25

30

35 CTDEP Biomass Indices

Spring Fall

Year

Surv

ey k

g/to

w

1980 1985 1990 1995 2000 2005 20100

1

2

3

4

5

6

7 NYDEC Abundance Index

NYDEC

Year

Surv

ey A

ge 2

+ N/

tow

1980 1985 1990 1995 2000 2005 20100

5

10

15

20

25

30

35

40

45 NJDFW Biomass Index

NJDFW

Year

Surv

ey k

g/to

w

1980 1985 1990 1995 2000 2005 20100.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

0

1

2

3

4

5

6

7

8

ChesMMAP and NEAMAP Biomass Indices

ChesMMAP NEAMAP Spring NEAMAP Fall

Year

Ches

MM

AP k

g/to

w

NEAM

AP k

g/to

w

NEFSC Spring Survey Indices by Age

Age (years)

1 2 3 4 5 6 7

Yea

r

1975

1980

1985

1990

1995

2000

2005

2010

+

NEFSC Fall Survey Indices by Age

Age (years)

0 1 2 3 4 5 6 7

Yea

r

1975

1980

1985

1990

1995

2000

2005

2010

+

NEFSC Winter Survey Indices by Age

Age (years)

1 2 3 4 5 6 7

Yea

r

1975

1980

1985

1990

1995

2000

2005

2010+

CTDEP Spring Survey Indices by Age

Age (years)

1 2 3 4 5

Yea

r

1975

1980

1985

1990

1995

2000

2005

2010

+

CTDEP Fall Survey Indices by Age

Age (years)

0 1 2 3 4 5

Yea

r

1975

1980

1985

1990

1995

2000

2005

2010

+

NYDEC Survey Indices by Age

Age (years)

0 1 2

Yea

r

1975

1980

1985

1990

1995

2000

2005

2010


• Status for 2011: Not Overfished; Not Overfishing• SSB2011 = 190,000 mt; • F2011 = 0.034 (fully recruited ages 2-7+); • R2011 = 154 million age 0 fish

• Currently no “internal” retrospective patterns

SSB (000s mt)

0 25 50 75 100 125 150 175 200

Fish

ing

Mor

talit

y

0.0

0.2

0.4

0.6

0.8

1.0

1.2

FMSY = F40% = 0.177

0.5*SSBMSY= 46,022 mt

SSBMSY = 92,044 mt

1996

1997

1998

1999

20002001 2002

20032004

20052006

2007 2009

1995

2008 20102011

1984

1985

1986

1987

1988

1989

1990

1991

1992

1993

1994

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

2007

2008

2009

2010

2011

0

20,000

40,000

60,000

80,000

100,000

120,000

140,000

160,000

180,000

200,000

Scup Assessment ComparisonMRIP: MRFSS ratio = 1.028

MRFSS MRIP

Year

SSB

(mt)

1984

1986

1988

1990

1992

1994

1996

1998

2000

2002

2004

2006

2008

2010

0

2,500

5,000

7,500

10,000

12,500

15,000

0.0

0.2

0.4

0.6

0.8

1.0

1.2

Total Catch and Fishing Mortality

Total Catch F

Year

Cat

ch (m

t)

Fish

ing

mor

talit

y (F

)

1984

1986

1988

1990

1992

1994

1996

1998

2000

2002

2004

2006

2008

2010

0

25,000

50,000

75,000

100,000

125,000

150,000

175,000

200,000

0

50

100

150

200

250

300

350

Spawning Stock Biomass (SSB) and Recruitment (R)

R SSB

Year

SSB

(mt)

R (a

ge 0

, mill

ions

)

0 25,000 50,000 75,000 100,000 125,000 150,000 175,000 200,0000

50

100

150

200

250

Scup S-R Datafor 1984-2011 Year Classes

SSB (mt)

R (a

ge 0

, mill

ions

) 2011


• A between-assessment comparison provides another measure of assessment uncertainty due to “historical retrospective” in model estimates

• The 2012 update SSB and F estimates are intermediate with respect to the 2008 DPSWG assessment and 2009 update estimates and close to the 2010-2011 update estimates;

• The 2012 recruitment estimates are in general larger compared to the 2011 assessment

1984

1986

1988

1990

1992

1994

1996

1998

2000

2002

2004

2006

2008

2010

0

25,000

50,000

75,000

100,000

125,000

150,000

175,000

200,000

Scup Assessment Comparison

DPS2008 S2009_UPDATES2010_UPDATE S2011_UPDATES2012_UPDATE

Year

SSB

(mt)

1984

1986

1988

1990

1992

1994

1996

1998

2000

2002

2004

2006

2008

2010

0.0

0.2

0.4

0.6

0.8

1.0

1.2


DPS2008 S2009_UPDATE S2010_UPDATES2011_UPDATE S2012_UPDATE

Year

Fish

ing

Mor

talit

y

1984

1986

1988

1990

1992

1994

1996

1998

2000

2002

2004

2006

2008

2010

0

50

100

150

200

250

300

350


DPS2008 S2009_UPDATES2010_UPDATE S2011_UPDATES2012_UPDATE 1984-2011 Mean

Year

Rec

ruits

: age

0 (m

illio

ns)

Scup (Stenotomus chrysops): 2012 Update• Short term projection for 2013 OFL

• Use 2008 DPSWG BRPs (SSBMSY = 92,044 mt; FMSY = 0.177)

• AGEPRO stochastic projection– resample 1984-2011 CDF of age 0 recruitment

• Note MSY = 13,134 mt of Total Landings + 3,027 mt Total Disc = 16,161 mt of Total Catch

• Specify Landings in 2012 = TAL = 16,749 mt; • Median Discards = 3,334 mt; median Total Catch = 20,083 mt • Median F2012 = 0.158, below FMSY• Median SSB2012 = 204,000 mt, above Btarget


• Specify F in 2013 = FSMY = 0.177

Total Catch = 21,680 mt = Overfishing Limit (OFL for 2013) Landings = 17,981 mt and Discards = 3,721 mt(note: independent medians so do not exactly total)

Median SSB2013 = 196,000 mt, above Btarget

Documents

Scup ( Stenotomus chrysops ): 2012 Update