Setting Catch Limits: Assessment, Peer Review,Targets, and Thresholds

Transcription

1 Setting Catch Limits: Assessment, Peer Review,Targets, and Thresholds Steve Ralston NOAA Fisheries SWFSC, Santa Cruz, CA Lingcod (Ophiodon elongatus) Courtesy Ray Troll

2 Four Fishery Management Plans Groundfish rockfish, roundfish, flatfish, elasmobranchs Salmon Chinook (king), coho (silver) Coastal pelagic species (CPS) sardine, mackerel, squid, anchovy Highly migratory species (HMS) tunas, billfish, pelagic sharks

3 Detailed Look at Groundfish Stock assessment process Peer review Targets and Thresholds (ACLs) Healthy stocks Rebuilding stocks Assemblage targets Starry flounder Platichthys stellatus Courtesy Ray Troll

4 Regulating PFMC Groundfish Harvests Stock Assessment Pacific Fishery Management Council Team Stock Assessment Terms of Reference science review Harvest Policy Wall of Science Socioeconomic, Allocation, and Other Issues A three meeting process, with a five month notice and comment period, to be conducted once every 2 years Exploitable Biomass Allowable Biological Catch (ABC) Optimum Yield (OY) OY < ABC Promulgate Regulations

5 Contents of Groundfish Stock Assessment Title Page and Authors Executive Summary Introduction Assessment Data landings, compositions, surveys, sample sizes, CVs, etc. Modeling History response to previous STAR and GAP comments Model Description fleets, likelihood components, constraints, etc. Model Selection parsimony vs. realism, likelihood profiles, residuals Base run all model parameters, time series, selectivities, S-R, etc. Reference Points Harvest Projections & Decision Tables Regional Management Considerations Research Needs Appendices parameter and data files

6 Stock Assessment Terms of Reference Introduction STAR Goals and Objectives Shared Responsibilities NMFS Responsibilities STAT Responsibilities GMT Responsibilities GAP Responsibilities SSC Responsibilities Council Staff Responsibilities Stock Assessment Priorities Terms of Reference for STAR Panels and Their Meetings Suggested Template for STAR Panel Report Terms of Reference for Groundfish STAT Teams Terms of Reference for Stock Assessment Updates Appendix A: Stock Assessment Review Calendar Appendix B: Outline for Groundfish Stock Assessment Documents Appendix C: Template for Executive Summary Prepared by STAT Teams Appendix D: Example of a Complete Stock Assessment Executive Summary

7 Full (Benchmark) Stock Assessments Full stock assessments are reviewed at a STock Assessment Review (STAR) panel STAR panels last a week, during which time two assessments are reviewed STAR panels have four scientific reviewers SSC member chairs meeting At least one (usually two) CIE One person with assessment experience gained on the US west coast Panels include representatives of the groundfish management (=plan) team and the advisory panel

8 Contents of Review Panel Report Summary of the STAR Panel meeting: Name and affiliation of panel members List of analyses requested, rationale, and response Description of base model and uncertainty Comments on the technical merits or deficiencies Explanation of areas of disagreement among Panel members and between STAR and STAT Unresolved problems and major uncertainties Issues raised by the GMT and/or GAP representatives Research priorities

9 Decision Tables to Express Uncertainty A creative role for the STAR panel Canary rockfish (Sebastes pinniger)

10 Updated Stock Assessments To qualify as an update a model must first be reviewed and certified by a full STAR panel. Only addition of newly acquired data (e.g., recent landings, survey results, compositions, etc.) is allowed All aspects of model structure must remain unchanged (turn the crank) Meeting is conducted by the SSC groundfish subcommittee and usually takes about 2 3 hours If a problem arises the assessment is referred to the mop up panel as a full assessment

11 SFA Biomass Based Control Rule (FMP Amendment 11) 0.20 Allowable Biological Catch / Optimum Yield ABC is based on Fmsy or its proxy OY is reduced if spawning potential is below 40% of K control rule for translating stock size into optimum yield strategy ABC 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% Spawning Output as a % of Virgin Spawning

12 The Rockfish Problem Relative Depletion 120% 100% 80% 60% 40% Canary Bocaccio Cowcod POP Darkblotched Widow Yelloweye 20% 0% Year

13 Harvests Based on Science 4,000 3,500 3,000 Stock assessments Canary rockfish Metric Tons 2,500 2,000 1,500 1, Catch ABC Year

14 Rebuilding Depends on Rate of Fishing Probability of rebuilding rebuilding with no fishing F=0 Tmin 1 generation Possible range of harvest 70% Years Tmax 50% bocaccio Sebastes paucispinis

15 What About Data Poor Stocks Approximately 80 species in groundfish FMP and only some 30 have been fully assessed with dynamic models Swept area biomass with F MSY = M approximation for a handful of rockfishes a 25% precautionary reduction in ABC is applied Many others have ABC set based on Restrepo et al. (historical landings) a 50% precautionary reduction in ABC is applied Species are aggregated into assemblages (e.g., slope rockfish north of lat N)

16 Salmon Management Over 60 salmon stocks designated in the FMP with conservation objectives Some stocks managed to meet ESA recovery goals and some for OY under Magnuson Act PFMC management focuses on sustainable fisheries while meeting NMFS imposed recovery goals Chinook salmon Oncorhynchus tshawytscha Courtesy Ray Troll

17 OY (Escapement Goal) Typically Based on Spawner Recruit Analysis A happy fisherman

18 Salmon Assessment Conducted intensively by Salmon Technical Team (STT) during March & April meetings Compile preceding year s data on catch and escapement Abundance of jacks (age 2 males) used to predict coming run through the use of sibling regressions

19 Sibling Regression Prediction can be for the entire run or for the same cohort (brood year)

20 Weak Stock Management Multiple stock escapement and exploitation rate goals are evaluated in the Chinook Fishery Regulation Analysis Model (FRAM) Time area impacts are modeled based on the ocean distribution and abundance of stocks as determined from coded wire tag returns Different season structures evaluated until all escapement & exploitation rates goals are met Happens quickly at March and April meetings

21 Salmon Peer Review Changes to methodology are reviewed and certified by the SSC salmon subcommittee in the Fall with Council approval in November Each year stock specific data from regional stakeholders are assembled, examined, and certified by the STT Run forecasts are presented to the SSC for review in March Occasional independent peer review on a specific issue (CIE review of KOHM in 2006)

22 2008 Pacific sardine assessment update

23 Pacific Sardine Harvest Control Rule HG t+1 = (Biomass t Escape min ) μ SST US portion 66,932 = (662, ,000) %

24 Control Rule is Environmentally Explicit Jacobson, L. D., and A. D. MacCall Stock-recruitment models for Pacific Sardine (Sardinops sagax). Can. J. Fish. Aquat. Sci. 52:

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