2017 AOP Panel Meeting - National Oceanic and Atmospheric ... · • i.e., Georges Bank cod...

2017 AOP Panel Meeting

Gulf of Maine Atlantic cod Michael Palmer NEFSC

Woods Hole, MA July 24, 2017

2015 update assessment • Stock status

• Issues and uncertainties • Two accepted models (M=0.2 and M-ramp), overall uncertainty in current levels

of natural mortality • M=0.2 model exhibits major retro pattern, M-ramp has minor retro pattern • Recent low recruitment compromises rebuilding potential

U.S. Department of Commerce | National Oceanic and Atmospheric Administration | NOAA Fisheries | Page 2

Assessment Proxy reference points M=0.2 M-rampFfull, 2014 0.956 (0.664 - 1.387) 0.932 (0.654 - 1.304)FMSY 0.185 0.187Ffull, 2014/FMSY 5.11 4.98Overfishing Yes YesSSB2014 (mt) 2,225 (1,713 - 2,892) 2,536 (1,942 - 3,298)SSBMSY (mt) 40,187 (27,551 - 58,228) 59,045 (44,976 - 76,525)SSB2014/SSBMSY 0.06 0.04Overfished Yes YesMSY (mt) 6,797 (4,608 - 9,990) 10,043 (7,560 - 13,130)Median age1 recruitment (000s) 4,406 (1,458 - 14,450) 8,965 (2,489 - 15,908)

2015 update

2017 update: anticipated challenges • Consideration of retrospective adjustment for M=0.2

model (moderate)

• Natural mortality assumptions for short-term projections (moderate)


2017 update: modelling approach • Update the SAW/SARC 55 ASAP models through 2016 • Update F40% FMSY proxies

• Use recent 3-year average weights • Update SSBMSY proxies

• 2012-2016 geometric mean for 2015 t+1 recruitment • 1982-2012 median for 2018 and beyond (model w/

recruitment declining to zero below hinge point) • Update short-term projections (2018-2020)

• 3 year example projections at FMSY proxy


2017 update: backup in the event of model failure • Application of recent survey trends to adjust recent

catch • i.e., Georges Bank cod approach

• Average index from NEFSC spring and fall surveys • LOESS smooth (span=0.3) of the 1982-2016 series • Fit log linear regression to last 3 years (2014-2016) • Compute proportional change (i.e., regression slope) • Apply to average catch from 2014-2016 to estimate a

proxy 2018 OFL


The end [Additional info as needed]


Georges Bank Atlantic Cod

• 2015 Operational Update – ASAP model not accepted – Empirical Approach used

• Plan B smooth

2017 Operational Update

• Update survey data and add recent years – NMFS spring and fall surveys

• Add recent catch • Apply Plan B smooth

– Based on EGB cod, expect increase in catch advice

2017 AOP Panel Meeting

Gulf of Maine haddock Michael Palmer NEFSC

Woods Hole, MA July 24, 2017

2015 Operational Assessment • Stock status

• Issues and uncertainties • Generally good model diagnostics • Size of the 2012 and 2013 year classes


Assessment Proxy reference points BaseFfull, 2014 0.257 (0.164 - 0.373)FMSY 0.468 (0.391 - 0.547)Ffull, 2014/FMSY 0.55Overfishing NoSSB2014 (mt) 10,325 (7,229 - 14,453)SSBMSY (mt) 4,623 (2,036 - 9,283)SSB2014/SSBMSY 2.23Overfished NoMSY (mt) 1,083 (489 - 2,148)Median age1 recruitment (000s) 1,335 (253 - 8,198)

2015 update

2017 update: anticipated challenges

• Evaluating uncertainty in recent year class strength • Anticipated to be a minor issue in the 2017 update

• Survey data do not indicate strong terminal year classes • Additional information to inform the 2012 and 2013 year classes

• Incorporation of revised recreational post-release mortality estimates (Mandelman et al.

2016 and 2017) • Current approach assumes 50% post-release mortality • Mandelman et al. work provides season and size-class specific mortality estimates • Application of the Mandelman et al. work has several challenges (described in Palmer

2017) • Only have lengths sampled directly from the recreational fishery from 2004 onward • Low length sample size when stratified by semester (~n=3)

• Unlikely to have perceptible impact on assessment results • Impact on estimates of total fishery removals from 2004 to 2016:

• Biomass: -1.2% - 3.3% • Numbers: -0.3% to 6.0%


2017 update: modelling approach • Update the SAW/SARC 59 ASAP model • Update F40% FMSY proxy

• Use recent 5-year average weights • Update SSBMSY proxy

• 1977-2016 geometric mean for 2017 t+1 recruitment • 1977-2014 median for 2016 and beyond

• Update short-term projections (2018-2020) • 3 year example projections at FMSY proxy


2017 update: backup in the event of model failure • Application of recent survey trends to adjust recent

catch • i.e., Georges Bank cod approach

• Average index from NEFSC spring and fall surveys • LOESS smooth (span=0.3) of the 1977-2016 series • Fit log linear regression to last 3 years (2014-2016) • Compute proportional change (i.e., regression slope) • Apply to average catch from 2014-2016 to estimate a

proxy 2018 OFL


The end [Additional info as needed]


Georges Bank Haddock

Liz Brooks NEFSC

July 24, 2017

Update Existing VPA (Ages 1-9+)

• Add US landings and discards (2015-2016) • Add Canadian landings and discards (2015-2016) • Add 2015-2016 NEFSC Fall BTS (ages 0-5) • Add 2016-2017 NEFSC Spring BTS and DFO Spring

(ages 1-8)

Update Stock Status • 2015 Stock Status (ρ-adjusted):

– Not overfished (SSB2014/SSBMSY= 1.38) – No overfishing (F2014/FMSY=0.62)

• Current Reference Points (based on F40%) • FMSY = 0.39; SSBMSY = 108,300 mt; MSY = 24,900 mt • Will update with recent 5 yr. average biological information

Projections

• Short-term projections at FMSY and 0.75*FMSY • Projection inputs: same assumptions as at GARM-III,

2012 and 2015 Updates: – Recent 5 yr. average for WAA, maturity AA, selectivity;

examine WAA trend for 2013 yclass – Sample cdf of recruitments, exclude 1963, 2003, 2010, 2013

and 2 most recent point estimates (2016, 2017) – Sensitivity projection will include the large year classes, but

still exclude most recent 2 point estimates – Perform bootstrap of VPA to obtain 1000 vectors of NAA in

year T+1 (2017) to initiate projections

Fall Back Plan

• Retrospective pattern in last assessment; if retrospective pattern continues, examine diagnostic and “rho adjust” if appropriate

• If VPA diagnostics not acceptable, use recent average catch

Proposed Update for Gulf of Maine Winter Flounder

Lead Scientist: Paul Nitschke Last Assessed: 2015 Operational Assessments

30+ Survey Area Swept

NEFSC

July 24, 2017

Current Status • Overfished status is Unknown • Overfishing not occurring


90% confidence intervals are shown for biomass and exploitation rate

Presenter

Presentation Notes

BRPs from CRD 12-06 Table L22

Assessment Plan • Update trends in the NEFSC, MDMF, and MENH

survey indices. • Estimate 2015 and 2016 30+ cm survey area swept

biomass for non-overlapping strata from the NEFSC, MDMF, and MENH surveys.

• Estimate 2015 and 2016 catch (commercial & recreational landing, recreational discards, large mesh trawl discards and gillnet discards).


Presenter

Presentation Notes

ABCs/recommended status is based on the terminal year of the fall index but will update through the spring 2017, if MENH and MDMF is available? 15% mortality rate assumed on rec b2s and 50% on commercial discards.

Assessment Plan 30+ cm Survey Area Swept Biomass Estimate. Used in SARC 52 (2011) and in the 2014 & 2015 Operational Updates.

• Exploitable Biomass = 30+ cm biomass index per tow x total survey area / tow footprint x q

• Exploitation rate = catch / 30+ cm biomass • Overfishing BRPs are based on F40% from length

based YPR with 30 cm knife edge selectivity (Not planning on updating F40% since overall von Bertalanffy growth is not expected to change much).


Presenter

Presentation Notes

F40% from overall von Bert growth in the length based YPR should not change much and I am not planning on updating this (wasn’t update in the 2015 op-up). If overall long term growth did actually change then questions would arise as to why this occurred. This may enter the benchmark realm? For example, did growth change due to oto sectioning or because overall growth is actually shifting over time? Also, if overall growth is changing then it may not be appropriate to lump all ages data together for the whole time series? This seems to be more of a benchmark question. Q is assumed to = 0.6 on wings.

Assessment Plan • Estimate Fall 2015-2016 and

Spring 2016-2017 30+ cm biomass from the NEFSC, MDMF and MENH surveys.


Presenter

Presentation Notes

The fall was used for status determination due to concerns of missing spawning fish within the estuaries during the spring which are not available to any survey. Some evidence of this can be seen in the state survey proportions spring verse fall. However in some years (2012 & 2013) the total spring estimates were higher than the fall which violates my theory.

The End?


Backup Plan C? There is no real plan C; unless a Q assumption change or multiyear 30+ area swept biomass (average fall and spring year t+1) average is considered a plan C?


Presenter

Presentation Notes

Would Q assumption changes and/or biomass estimate based on averages from the reviewers be considered a plan C?

Cape Cod-Gulf of Maine Yellowtail Flounder

Larry Alade 2017 Groundfish Operational Assessment Plan

Population Dynamics Branch Northeast Fisheries Science Center

July 24, 2017

Previous 2015 Operational Assessment

• Last assessed in the 2015 Groundfish Operational Assessment

• VPA Model (1985-2014); Ages 1-6+ – VPA tuned to six age-specific Surveys:

• NEFSC and Mass DMF (Spring Ages 1-6+; Fall Ages1-5) • ME/NH surveys (Spring 2-5; Fall 2-4)

– Age and time invariant M = 0.2 – Commercial Catch (landings plus discards)

• Stock Status – Overfished and overfishing occurring

2017 OA Base Plan: Update Existing VPA Model

• Update Fishery dependent data – Comm. landings and discards = CAA (2015-2016)

• Update NEFSC, Mass DMF, and ME/NH surveys and age comp: Spring (2016-2017) and Fall (2015- 2016) – NEFSC Surveys - Bigelow length based calibration

factors available from peer review in TRAC 2010 • Biological: No changes to M, maturity (age

specific and time invariant), or timing of spawning.

Biological reference points and Stock Status

• 2017 Operational Assessment Update – Update Stock Status with 2016 values:

• Current Status: Overfished (SSB2014/SSBMSY= 0.16), Overfishing (F2014/FMSY=2.3)

– Update Biological Reference Points

• Fishing reference points (based on F40%) • Biomass reference points:

– Recruitment (1985-2014 + Hindcast back to 1977 per Rec. from GARM III)

– 5 yr mean WAA, maturity and selectivity (2012-2016) • Current reference points

– FMSY = 0.279; SSBMSY = 5,259 mt; MSY = 1,285 mt

Projections • Short-term projections (Median catch 2018-2020)

– Fstatus quo (F = F2016) – FMSY = F40% (YPR) – 75%FMSY

• CCGOM under rebuilding plan (End date = 2023) – Frebuild (Iterative approach for yrs 2018-2023)

• Projection inputs same assumptions as previous 2015 OA (Basis: GARM III): – Recent 5 yr. average for WAA, maturity AA, selectivity – Sample cdf of recruitments (including hindcast values) – Bootstrap VPA to obtain 1000 vectors of NAA in year T+1

(2017) to initiate projections


• In the last 2015 Operational Assessment – Quality of model fit was somewhat consistent

with previous assessment (2012 update and 2015 OA)

– However retrospective pattern was stronger and retro adjustment was implemented

Plan B (Only If necessary)

• Empirical Assessment approach – Apply Catchability estimates from the twin trawl Study

to expand survey catch/tow to absolute biomass estimates.

• Bigelow estimates (Fall and Spring Survey) – Exploitation rate will applied to survey biomass

estimates to generate catch advice. • Catch Advice: Period for exploitation rate (undetermined) • GB Yellowtail, range of exploitation rates were mgt. catch

quota – Biomass reference points – Unknown

Larry Alade 2017 Groundfish Operational Assessment Plan

Population Dynamics Branch Northeast Fisheries Science Center

July 24, 2017

Southern New England-Mid Atlantic Yellowtail Flounder

Previous Assessment

• Last assessed: 2015 Groundfish Operational Assessment

• ASAP Model (1973-2014); Ages 1-6+ – ASAP tuned to three age-specific surveys and a larval

index: • NEFSC (Spring ages 1-6+ 1973-2015; Fall ages 1-6+ for years

1973-2014) • Larval abundance Index (Summer 1977-1987; 1995-2015)

– Time invariant, age-specific M – Commercial Catch (Landings plus discards) - CAA

• Discards: Apply 90% Discard Mortality (Barkley and Cadrin, 2012)

– Stock Status : Overfished and overfishing is occurring

2017 OA Base Plan: Update Existing ASAP model

• Update US landings and discards Incl. CAA (2015-2016) – Update fishery selectivity blocks as necessary

• Add NEFSC, Fall and Spring (2015-2016) and larval abundance index (2015-2016) – Bigelow length based calibration factors available from

peer review in TRAC 2010 • Biological:

– No changes to M – No changes to Maturity, or timing of spawning

Update Existing Biological Reference Points and Stock Status

• 2017 Operational Assessment Update

– Update Stock Status: • Current status: Overfished (SSB2014/SSBMSY= 0.26), and

Overfishing is occurring (F2014/FMSY= 4.69)

– Update Biological reference points: • Fishing Reference Points (based on F40%) • Biomass reference points:

– Two Stage cdf of recruitment series (1973-2015) – Recent 5 yr mean WAA, maturity and Selectivity (2012-2016)

• Current reference points: – FMSY = 0.35; SSBMSY = 1,959 mt; MSY = 541 mt

Projections • Short-term projections (median catch 2018-2020)

– FStatus quo (F = F2016) – FMSY = F40%

– 75%FMSY

• Projection inputs assumptions = SARC 54: – Recent 5 yr. average for WAA, maturity AA, selectivity

(2012-2016) – Two stage Sampling cdf of recruitments series (1973 -

2015) – ASAP MCMC simulations to obtain 1000 vectors of NAA in

year T+1 (2017) to initiate projections


• Quality of model fit to input data was relatively consistent.

• However, emergence of strong retrospective pattern

• If model diagnostics continues to deteriorate with regards both precision and retrospective bias…..Then develop Plan B

Plan B (Only if necessary)

• Empirical Assessment approach – Apply Catchability estimates from the twin trawl Study

to expand survey catch/tow to absolute biomass estimates.

• Bigelow estimates (Fall and Spring Survey) – Exploitation rate will applied to survey biomass

estimates to generate catch advice. • Catch Advice: Period for exploitation rate (undetermined) • GB Yellowtail, range of exploitation rates were mgt. catch

quota – Biomass reference points – Unknown

Georges Bank Yellowtail Flounder

• 2015 Operational Update – Presented for information only – Empirical Approach used

• Survey expansion

2017 Operational Update

• Presented for information only • TRAC met July 11-14, 2017 • SSC to meet August 8 • Empirical approach used (survey expansion)

– Changed survey q (0.37 to 0.31) – Change survey tow area (door spread to wing

spread) – Still recommend decrease in catch due to

declining surveys

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2017 AOP Panel Meeting - National Oceanic and Atmospheric ... · • i.e., Georges Bank cod...

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