Science Advisory Report  2012/025

Reference points for American Plaice (Hippoglossoides platessoides) in NAFO Subarea 2 + Division 3K and Subdivison 3Ps

Summary

Subarea 2 + Division 3K

• Total mortality due to all causes, including fishing, has been decreasing on more recent cohorts.
• In Div. 2J3K, an empirical biological limit reference point (LRP) was determined from examining stock recruit data from the RV survey. Generally recruitment has been impaired when the survey SSB index is below 70 000 t and therefore this was chosen as the LRP. It may be necessary to re-evaluate the LRP once more data are available at higher SSB (as SSB approaches the LRP).
• The 2009 estimate of survey SSB indicates that the stock is at 24% of the LRP. Estimates are not yet available for 2010 and 2011.
• It was not possible to determine an upper reference point or a removals (F-based) reference point for this stock.

Subdivision 3Ps

• A Bayesian Surplus Production Model was applied to catch data from 1960-2010 and survey data from 1980-2010 for American Plaice in Subdiv. 3Ps. Consistent with the DFO PA policy Blim is 40% B_msy, the upper stock reference is 80% B_msy and F_lim is F_msy. Stock status relative to these reference points was estimated from the model.
• Stock size estimated from this model has been increasing slowly since 1993, however, current biomass is 50% of B_lim and therefore the stock is in the critical zone. The probability of being below B_lim is high (0.94). Current fishing mortality is estimated to be 64% of F_lim. The probability of being above F_lim is 0.2.

This Science Advisory Report is from the Fisheries and Oceans Canada, Canadian Science Advisory Secretariat, Regional Peer Review meeting of March 20-21, 2012, An Update of Stock Status and Determination of Limit Reference Points for the American Plaice stocks in i) NAFO Subarea 2+ Division 3K, and ii) NAFO subdivision 3Ps. Additional publications from this process will be posted as they become available on the DFO Science Advisory Schedule.

Complete document (PDF, 275 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.