Terms of Reference

Stock Structure of Dungeness Crab (Metacarcinus magister) in British Columbia

Regional Peer Review - Pacific Region

March 11-13, 2025

Nanaimo, BC

Chairperson: Katie Gale

Context

The commercial Dungeness Crab fishery in British Columbia (BC) has been in existence for over 100 years. Fisheries and Oceans Canada (DFO) manages the crab fishery which consists of 7 Crab Management Areas (CMAs; A, B, E, G, H, I, and J) in BC. Dungeness Crab fisheries are primarily managed based on a ‘3 S’ (size, sex, and season) management strategy. This management strategy is designed to allow sexually mature sublegal male crabs 1-2 reproductive seasons prior to recruiting into the fishery, to protect female crabs, and to protect crabs during vulnerable softshell periods.

To ensure that Dungeness Crab complies with the Fish Stock Provisions of the Fisheries Act, and DFO’s Precautionary Approach (DFO 2009), DFO must estimate reference points and stock status. Before this can be achieved, the stock structure of Dungeness Crab in BC first needs to be defined. Understanding the biological scale of the stock is important to avoid biased assessments and potentially localized depletions (e.g., Ying et al, 2011). This requires reviewing all relevant information on the biological population structure of Dungeness Crab in British Columbia to inform the spatial scale of future management.

Fisheries and Oceans Canada (DFO) Fisheries Management Branch has requested an evaluation of the stock definition for Dungeness Crab in British Columbia from the Science Branch.

The advice arising from this Canadian Science Advisory Secretariat (CSAS) Regional Peer Review (RPR) process will be used to inform resource managers on the stock definition of Dungeness Crab in BC. This definition will be used in future work, by informing the scale at which management tools such as reference points should be applied.

Objectives

The following working paper will be reviewed and provide the basis for discussion and advice on the specific objectives outlined below.

Brendan Aulthouse, Meghan Burton, Kyle Krumsick, Shannon Obradovich, Andres Araujo. Stock Structure of Dungeness crab (Metacarcinus magister) in British Columbia. 2025. CSAP Working Paper 2025

The specific objectives of this review are to:

1. Evaluate the stock definition for Dungeness Crab in BC given all available information and data on genetics, life history, fishery characteristics, and oceanography; and
2. Identify and discuss key uncertainties and knowledge gaps as they pertain to the stock definition.

Expected Publications

• Science Advisory Report
• Research Document

Expected Participation

• Fisheries and Oceans Canada (Science, and Fisheries Management sectors)
• Academia (e.g. University of British Columbia)
• First Nations
• Commercial Industry
• Sport Fishing Advisory Board

References

• DFO. 2009. A Fishery Decision-Making Framework Incorporating the Precautionary Approach. Fisheries and Oceans Canada.
• Ying, Y., Chen, Y., Lin, L., and Gao, T. 2011. Risks of ignoring fish population spatial structure in fisheries management. Canadian Journal of Fisheries and Aquatic Sciences 68(12): 2101–2120.