Terms of Reference

Stock Status Update and Harvest Options for the Green Sea Urchin (Strongylocentrotus droebachiensis) fishery in British Columbia, 2021-2024

Science Response Process – Pacific Region

June 30, 2021
Virtual Meeting

Chairperson: Lyanne Curtis

Context

Stock assessments and harvest options for British Columbia’s Green Sea Urchin (Strongylocentrotus droebachiensis) fishery are conducted every two or three years. They provide advice to Fisheries and Oceans Canada (DFO) Fisheries Management for the development of the fishery’s multi-year Integrated Fishery Management Plans (IFMPs). The last stock status update was conducted in 2018 (DFO 2018a). The present process will update the previously published assessment results using the most recently available commercial catch and survey information (Perry et al. 2003; Zhang and Perry 2005; Perry et al. 2006; Waddell et al. 2010, DFO 2014, DFO 2016, DFO 2018a).

British Columbia’s Green Sea Urchin commercial fishery currently takes place in two regions of the coast: Northeast Vancouver Island (Pacific Fisheries Management Area - PFMAs; 11, 12 and 13), and Southeast Vancouver Island (PFMAs 18, 19 and 20). Since the last update, fisheries independent surveys were conducted in PFMAs 12 and 19, and are now conducted on a three-year rotation. In 2018, provisional reference points compliant with the DFO’s Fishery Decision-Making Framework Incorporating the Precautionary Approach (DFO 2009) were recommended (DFO 2018a) and subsequently implemented in the fishery (DFO 2018b). Using these reference points, Green Sea Urchin stock status can be estimated in Northeast and Southeast Vancouver Island management regions, where the long-term index sites are located.

DFO Fisheries Management has requested that Science Branch assess the status of the Green Sea Urchin stock open to commercial fishing, relative to the provisional reference points, highlight recent trends in local populations and population structure, and provide ranges of harvest options for the commercial harvest areas for Northeast (PFMAs 11, 12, 13) and Southeast (PFMAs 18, 19 and 20) Vancouver Island. The assessment, and advice arising from this Canadian Science Advisory Secretariat (CSAS) Science Response (SR), will be used to inform the development of the IFMP.

Objectives

The objectives for this Science Response are to:

1. Evaluate stock status of Green Sea Urchins in Northeast (PFMAs 11, 12, 13) and Southeast Vancouver Island (PFMAs 18, 19, 20) using the provisional reference points and density estimates derived from biological surveys within each management region;
2. Provide the ranges of sustainable harvest options and their associated risks for Northeast Vancouver Island (PFMAs 11, 12, 13) and Southeast Vancouver Island (PFMAs18, 19, 20);
3. Analyse index site survey data and present the recent trends in the local populations and population structure for Green Sea Urchins;
4. Examine and identify uncertainties in the data and methods; and
5. Provide recommendations for additional research or stock assessment programs.

Expected Publication

• Science Response

Expected Participation

• Fisheries and Oceans Canada (DFO) (Ecosystems and Oceans Science, and Fisheries Management sectors

References

• DFO 2009. A Fishery Decision-Making Framework Incorporating the Precautionary Approach.
• DFO. 2014. Stock status update and quota options for the Green Sea Urchin (Strongylocentrotus droebachiensis) fishery in British Columbia, 2013-2016 DFO Can. Sci. Advis. Sec. Sci. Resp. 2014/052.
• DFO. 2016. Stock Status Update and Harvest Options for the Green Sea Urchin (Strongylocentrotus droebachiensis) Fishery in British Columbia, 2016-2019. DFO Can. Sci. Advis. Sec. Sci. Resp. 2016/031.
• DFO. 2018a. Stock Status Update and Harvest Options for the Green Sea Urchin (Strongylocentrotus droebachiensis)Fishery in British Columbia, 2019-2021.DFO Can. Sci. Advis. Sec. Sci. Resp. 2018/054.
• DFO. 2018b. Pacific Region 2018-21 Green Sea Urchin Integrated Fisheries Management Plan.
• Perry, R.I., Zhang, Z., and Waddell, B.J. 2003. Assessment of green sea urchin (Strongylocentrotus droebachiensis) stocks in British Columbia, 2003. DFO Can. Sci. Advis. Sec. Res. Doc. 2003/082. 55 p
• Perry, R.I., Zhang, Z., and Waddell, B. 2006. Stock assessment and quota options for the Green Sea Urchin Strongylocentrotus droebachiensis fishery in British Columbia, 2006-2009. DFO Can. Sci. Advis. Sec. Sci. Advis. Rep. 2005/064.
• Waddell, B., Zhang, Z., and Perry, R.I. 2010. Stock assessment and quota options for the green sea urchin, Strongylocentrotus droebachiensis, fishery in British Columbia, 2010-2013. DFO Can. Sci. Advis. Sec. Res. Doc. 2010/027. vi + 36 p.
• Zhang, Z., and Perry, R.I. 2005. Use of state-space modeling with a Bayesian approach to estimate target reference points for green sea urchin (Strongylocentrotus droebachiensis) stocks in the Queen Charlotte Strait regions, British Columbia, Canada. Fish. Res. 74: 253-264.