Terms of Reference

A revised operating model for Sablefish (Anoplopoma fimbria) in British Columbia, Canada

Regional Peer Review – Pacific Region

January 20, 2016
Nanaimo, British Columbia

Co-chairs: John Holmes and Julia Bradshaw

Context

Fisheries and Oceans Canada (DFO) and the British Columbia (BC) Sablefish fishing industry collaborate on a management strategy evaluation (MSE) process intended to develop and implement a transparent and sustainable harvest strategy. Sustainability of harvest strategies is determined by simulation testing alternative management procedures against operating models that represent a range of hypotheses about uncertain Sablefish stock dynamics. Performance of management procedures used in these tests is measured against pre-agreed conservation and catch objectives for the stock and fishery (Cox et al. 2011, DFO 2014).

The existing Sablefish fishery operating models were developed to represent alternative hypotheses about natural mortality rates, at-sea release mortality rates, individual growth rate, and recruitment autocorrelation. These processes are all fundamental to fish population dynamics, yet are typically the most difficult parameters to estimate reliably from fisheries data. The models are structured by age (25+ age-classes) and also by 30 growth groups; the latter dimension is added as part of an evaluation of size-based discarding, selective grading of fish at sea, and potential regulatory changes aimed at reducing these activities. Operating models were fitted to available data for the BC Sablefish fishery to estimate model parameters conditional on each hypothesis for subsequent simulation testing of alternative management procedures.

The Fisheries Management Branch of Fisheries and Oceans Canada requested advice from Science Branch to continue development of the Sablefish operating model to improve model structure and ability to represent uncertain biological and fishery processes prior to a full collaborative MSE process planned for 2016/17.

Objectives

Guided by the DFO Sustainable Fisheries Framework, particularly the Fishery Decision-making Framework Incorporating the Precautionary Approach (DFO 2009), meeting participants will review the working paper:

• A revised operating model for the Sablefish (Anoplopoma fimbria) fishery in British Columbia, Canada. S.P. Cox, A.R. Kronlund, and L. Lacko. CSAP Working Paper 2014GRF03.

The working paper will be used to provide advice with respect to the following objectives:

1. Review a revised Sablefish operating model and assess suitability for simulating realistic data that represent stock and fishery process such as natural mortality rates, sexually dimorphic growth, fishery selectivity, at-sea release mortality rates, recruitment dynamics, and changes in future division of catch among gear types.
2. Propose candidate operating model hypotheses to be used for subsequent evaluation of management procedures for the collaborative MSE process planned for 2016/17.

Expected Publications

• CSAS Science Advisory Report
• CSAS Research Document
• CSAS Proceedings

Participation

• DFO (Science, Fisheries Management)
• Aboriginal communities
• Province of British Columbia
• External reviewers
• Industry
• Non-governmental organizations and other scientists and stakeholders.

References

Cox, S.P., Kronlund, A.R., Lacko, L. 2011. Management procedures for the multi-gear Sablefish (Anoplopoma fimbria) fishery in British Columbia, Canada. DFO Can. Sci. Advis. Sec. Res. Doc.2011/063. viii + 45 p.

DFO. 2009. A Fishery Decision-making Framework Incorporating the Precautionary Approach.

DFO. 2014. Performance of a revised management procedure for Sablefish in British Columbia. DFO Can. Sci. Advis. Sec. Sci. Resp. 2014/025.