Terms of Reference

2024/2025 Pacific Herring Stock Assessment, Forecast of Mature Stock Biomass, and Harvest Options for 2025 (HG, PRD, CC, WCVI)

Regional Peer Review - Pacific Region

September 23, 2024

Virtual meeting

Chairperson: Chris Rooper

Context

Pacific Herring (Clupea pallasii) in British Columbia are managed by Fisheries and Oceans Canada (DFO) based on five major and two minor stock assessment regions (SARs). The major SARs are Haida Gwaii (HG), Prince Rupert District (PRD), Central Coast (CC), Strait of Georgia (SoG), and West Coast of Vancouver Island (WCVI); the minor SARs are Haida Gwaii Area 2W (A2W) and WCVI Area 27 (A27).

Annual assessments of Pacific Herring abundance and forecasts began in the late-1980s for all major SARs. Starting in 2006, the assessment has used an integrated statistical catch-age (SCA) model fit to commercial catch data, biological data (i.e., proportion- and weight-at-age), and a fishery-independent abundance index of herring spawn derived from egg deposition surveys (i.e., the spawn index). The SCA model estimates spawning biomass and forecasts spawning biomass for the next year (Martell et al., 2012, DFO 2018, Cleary et al. 2019). Since 2015, Fisheries Management quota decisions have been based on a SCA model that assumes the spawn index is an absolute index of herring biomass (i.e., q=1). The SCA model will use this parameterization in 2024, following comparisons presented in DFO (2016; Table A1) and a bridging analysis (Cleary et al. 2019; Appendix D). The 2024 stock status update for HG, PRD, CC, and WCVI herring stocks will include data updates for 2024, and use the same SCA model reviewed in 2017 (Cleary et al. 2019) and implemented annually in years 2017-2023.

A management strategy evaluation (MSE) framework was first implemented in the Herring advisory process in 2018 (Benson et al. 2023; DFO 2020). Management advice for Pacific Herring in SoG and WCVI for the 2018/19 fisheries was derived from a peer reviewed analysis which simulation-tested management procedures (MPs; DFO 2019) as part of the MSE process. Subsequently, the first MSE cycle for the remaining major SARs was completed using methods outlined in DFO (2019a), and resulted in simulation-tested MPs for HG, PRD, and CC. Since 2018, updates for each SAR have occurred every 1-3 years, with the most recent MP updates presented in 2022 and implemented in 2023 and 2024 (DFO 2022, DFO 2023a, DFO 2024).

In June 2023, a Canadian Science Advisory Secretariat (CSAS) regional peer review process reviewed and accepted the “Application of a new modelling framework for the assessment of Pacific Herring (Clupea pallasii) major stocks and implementation in the management strategy evaluation process”^{Footnote 1}. The review (DFO 2023b) recommended a process for implementing the new assessment and operating model, updates to the management strategy evaluation process, and identification of exceptional circumstances should be developed in a phased approach in consultation with managers, First Nations and stakeholders. The outcome was to apply the new modelling framework this year for SoG and is described in a separate TOR.

DFO Fisheries Management has requested that DFO Science provide Pacific Herring stock status updates for 2024 and harvest advice for 2025 derived from simulation-tested MPs in 2022 for these 4 SARs: HG, PRD, CC, and WCVI. The assessment and advice arising from this CSAS Science Response (SR) process, using methods detailed in Cleary et al. (2019), and available peer-reviewed data, will be used to support the development of the 2024/2025 Integrated Fisheries Management Plan.

Objectives

Guided by the DFO Fishery Decision-making Framework Incorporating the Precautionary Approach (DFO 2009) under the Sustainable Fisheries Framework, a CSAS SR will be developed to provide the following information for the HG, PRD, CC, and WCVI SARs to:

1. Update stock and fishery status for 2024.
2. Estimate biomass, depletion, and recruitment.
3. Assess stock status relative to established reference points.
4. Summarize the spatial distribution of the spawn index (e.g., by Statistical Area).
5. Provide harvest advice for 2024/2025 for each major SAR using simulation-tested MPs.
6. Update stock trends using available spawn index and biological data for the minor SARs and Area 10.

Expected Publications

• Science Response

Expected Participation

• DFO Science and Fisheries Management

References

• Benson, A.J., Cleary, J.S., Cox, S.P., Johnson, S., and Grinnell, M.H. 2023. Performance of management procedures for British Columbia Pacific Herring (Clupea pallasii) in the presence of model uncertainty: closing the gap between precautionary fisheries theory and practice. DFO Can. Sci. Advis. Sec. Res. Doc. 2022/048. viii + 70 p.
• Cleary, J.S., Hawkshaw, S., Grinnell, M.H., and Grandin, C. 2019. Status of B.C. Pacific Herring (Clupea pallasii) in 2017 and forecasts for 2018. DFO Can. Sci. Advis. Sec. Res. Doc. 2018/028. v + 282 p.
• Cox, S.P., Benson, A.J., Cleary, J.S, and Taylor, N.G. 2019. Candidate Limit Reference Points as a Basis for Choosing Among Alternative Harvest Control Rules for Pacific Herring (Clupea pallasii) in British Columbia. DFO Can. Sci. Advis. Sec. Res. Doc. 2019/050. viii + 47 p.
• DFO. 2009. A fishery decision-making framework incorporating the Precautionary Approach.
• DFO. 2016. Stock Assessment and Management Advice for BC Pacific Herring: 2016 Status and 2017 Forecast. DFO Can. Sci. Advis. Sec. Sci. Resp. 2016/052.
• DFO 2018. Stock Assessment and Management Advice for BC Pacific Herring: 2017 Status and 2018 Forecast. DFO Can. Sci. Advis. Sec. Sci. Advis. Rep. 2018/002.
• DFO. 2019. Evaluation of Management Procedures for Pacific Herring (Clupea pallasii) in the Strait of Georgia and the West Coast of Vancouver Island Management Areas of British Columbia. DFO Can. Sci. Advis. Sec. Sci. Advis. Rep. 2019/001.
• DFO. 2020. Stock status update with application of management procedures for Pacific Herring (Clupea pallasii) in British Columbia: Status in 2019 and forecast for 2020. DFO Can. Sci. Advis. Sec. Sci. Resp. 2020/004.
• DFO. 2022. Stock status update with application of management procedures for Pacific Herring (Clupea pallasii) in British Columbia: Status in 2022 and forecast for 2023. DFO Can. Sci. Advis. Sec. Sci. Resp. 2022/046.
• DFO. 2023a. Management Strategy Evaluation Update and Evaluation of Upper Stock Reference Point Options for Pacific Herring (Clupea pallasii) in British Columbia, Canada. DFO Can. Sci. Advis. Sec. Sci. Resp. 2023/002.
• DFO. 2023b. Application of a new modelling framework for the assessment of Pacific Herring (Clupea pallasii) major stocks and implementation in the management strategy evaluation process. DFO Can. Sci. Advis. Sec. Sci. Advis. Rep. 2023/040.
• DFO. 2024. Stock Status Update with Application of Management Procedures for Pacific Herring (Clupea pallasii) in British Columbia: Status in 2023 and Forecast for 2024. DFO Can. Sci. Advis. Sec. Sci. Resp. 2024/001.
• Kronlund, A.R., Forrest, R.E., Cleary, J.S., and Grinnell, M.H. 2018. The selection and role of limit reference points for Pacific Herring (Clupea pallasii) in British Columbia, Canada. DFO Can. Sci. Advis. Sec. Res. Doc. 2018/009. ix + 125 p.
• Martell, S.J., Schweigert, J.F., Haist, V., and Cleary, J.S. 2012. Moving towards the sustainable fisheries framework for Pacific herring: data, models, and alternative assumptions; Stock Assessment and Management Advice for the British Columbia Pacific Herring Stocks: 2011 Assessment and 2012 Forecasts. DFO Can. Sci. Advis. Sec. Res. Doc. 2011/136. xii + 151 p.