Terms of Reference

Assessment of Nova Scotia (4VWX) Snow Crab

Regional Peer Review - Maritimes Region

February 24, 2015
Dartmouth, Nova Scotia

Chairperson: Kristian Curran

Context

Snow crab has been a dominant macro-invertebrate in the Scotian Shelf Ecosystem (SSE) since the decline of the groundfish. They are observed in large numbers in deep, soft-bottom substrates ranging from 60-280 m water depths and at temperatures generally less than 6°C. Snow crab in this area is in the southern-most extreme of its spatial distribution in the Northwest Atlantic. The snow crab fishery has been in existence in Nova Scotia since the early 1970s. It occurs annually throughout the year dependent upon the Crab Fishing Area (CFA). In support of the fishery, DFO Maritimes Fisheries and Aquaculture Management Branch has requested that DFO Science Branch assess the status of the resource and consequences of various harvest levels for the coming fishing season. The last assessment of snow crab was conducted in February 2014 (Cook et al. 2014; DFO 2014)

Objectives

The objectives for this science advisory assessment meeting are:

• Assess the overall status of 4VWX snow crab stocks as of the end of the 2014 season using the following indicators:
  • Abundance
    • Snow crab survey biomass index of males greater than 95 cm (commercial sizes)
  • Recruitment
    • Snow crab survey R-1 relative abundance
  • Exploitation Rate
    • Incidence of CC5 crab in the survey
    • Relative exploitation rate from the survey
  • Report on
    • Commercial catch rates in the 2013 fishery, compared to those in previous years
    • Abundance of female crab from the survey
• Evaluate the consequences of different harvest levels during the 2014 fisheries on stock abundance and exploitation rate.
• Report on the bycatch of non-target species in the snow crab fishery in 2013 and identify any notable changes in the occurrence of these bycatch species relative to previous years.
• Describe any relevant predator/prey interactions.

Expected Publications

• Science Advisory Report  
• Proceedings 
• Research Document

Participation

• DFO Maritimes Science 
• DFO Maritimes Fisheries and Aquaculture Management
• Provincial Government representatives
• Industry
• Aboriginal Organizations
• Environmental Non-government Organizations
• Other

References

DFO. 2014. Assessment of Nova Scotia (4VWX) Snow Crab. DFO Can. Sci. Advis. Sec. Sci. Advis. Rep. 2014/033.

Cook, A. M., Zisserson, B.M., Cameron, B.J. and Choi, J.S. 2014. Assessment of Scotian Shelf Snow Crab in 2013. DFO Can. Sci. Advis. Sec. Res. Doc. 2014/052. Vi + 101 p.