Science Advisory Report 2018/007

Assessment of snow crab (Chionoecetes opilio) in the southern Gulf of St. Lawrence (Areas 12, 19, 12E and 12F) to 2017 and advice for the 2018 fishery

Summary

• Snow crab in the southern Gulf of St. Lawrence is considered as a single stock unit for assessment purposes. This stock unit comprises of fishing areas 12, 19, 12E, and 12F.
• The landings of snow crab from the southern Gulf of St. Lawrence in 2017 were 43,656 t from a revised quota of 43,475 t.
• The resulting exploitation rate of the 2017 fishery in the southern Gulf of St. Lawrence was estimated at 44%.
• The 2017 post-fishery survey biomass of commercial-sized adult male crabs was estimated at 66,021 t (95% confidence interval of 57,456 to 75,495 t), a decrease of 33.4% from 2016. The available biomass for the 2018 fishery, derived from the 2017 survey, is within the healthy zone of the Precautionary Approach (PA) framework.
• Total commercial biomass in the 2017 survey was composed 78% of new recruitment (51,262 t) and 22% of residual biomass (14,759 t). The recruitment to the commercial biomass decreased by 31% relative to the previous year.
• Based on the agreed harvest decision rule which has been assessed as compliant with the PA, the point estimate of the biomass in the 2017 survey of 66,021 t corresponds to an exploitation rate of 38.3% and a Total Allowable Catch (TAC) of 25,286 t for the 2018 fishery.
• The risk analysis indicates that the 2018 TAC derived from the harvest decision rule would result in a near 100% chance of the biomass for the 2019 fishery being above BUSR and in the healthy zone of the PA.

Fishery performance in 2017 in Area 12

• The 2017 landings in Area 12 were 39,825 t from a revised quota of 39,651 t.
• The CPUE (expressed as kg per trap haul (kg/th)) in 2017 (72.0 kg/th) increased compared to 2016 (64.0 kg/th).
• The incidence of soft-shelled crab in 2017 (6.0%) was comparable to 2016 (5.3%).

Fishery performance in 2017 in Area 19

• The 2017 landings in Area 19 were 2,944 t from a revised quota of 2,945 t.
• The CPUE in 2017 (142.8 kg/th) was comparable to 2016 (142.5 kg/th).
• The incidence of white-crab increased from 8.2% in 2016 to 11.6% in 2017.

Fishery performance in 2017 in Area 12E

• In Area 12E, the landings were 203 t from a revised quota of 199 t.
• The CPUE in 2017 (60.9 kg/th) increased compared to 2016 (51.5 kg/th).
• The incidence of soft-shelled crab in 2017 remained low, at 2.0% compared to 1.1% in 2016.

Fishery performance in 2017 in Area 12F

• The 2017 landings in Area 12F were 684 t from a revised quota of 680 t.
• The CPUE in 2017 (72.6 kg/th) increased compared to 2016 (43.9 kg/th).
• The incidence of soft-shelled crab decreased from 10.4% in 2016 to 1.9% in 2017.

This Science Advisory Report is from the Fisheries and Oceans Canada, Canadian Science Advisory Secretariat, regional advisory meeting of January 24-25, 2018 on the Stock assessment of the southern Gulf of St. Lawrence snow crab stock to 2017 and catch advice for the 2018 fishery. Additional publications from this process will be posted on the Fisheries and Oceans Canada (DFO) Science Advisory Schedule as they become available.

Complete document (PDF, 1,090 KB)

Accessibility Notice

This document is available in PDF format. If the document is not accessible to you, please contact the Secretariat to obtain another appropriate format, such as regular print, large print, Braille or audio version.