Research Documentt 1998/15

An assessment of the cod stock in NAFO Divisions 2J+3KL

By G.R. Lilly, P.A. Shelton, J. Brattey, N. Cadigan, E.F. Murphy, D.E. Stansbury, M.B. Davis, D.W. Kulka, and M.J. Morgan

Abstract

A Canadian moratorium on directed fishing has been in effect for the 2J+3KL cod stock since July 1992. Catches in 1993-1997 came from various combinations of by-catch, food fisheries, and sentinel surveys. The catch in 1997 was reported as 505 tons, consisting of 159 tons from by-catch and 346 t from sentinel surveys. The quantity of cod in offshore waters, as determined from bottom-trawl surveys, continued to be only 1-2% of values in the period 1983-1989. The total mortality rate estimated from the autumn surveys in 1995-1997 was very high (Z=0.77). The quantity of cod in the inshore remains uncertain. Catch rates in the inshore sentinel surveys were poor in Division 2J and in Division 3K north of White Bay, but were considered by sentinel fishers to be good at many sites from White Bay south. Nevertheless, an acoustic survey in inshore waters from White Bay to St. Mary's Bay in southern Division 3L provided a biomass estimate of only 18,000 t. A biologically justifiable analytical assessment was not achieved, as catches could not be reconciled with the autumn research vessel index. An exploration of current stock productivity indicated that the spawner biomass may decline in the absence of a fishery if the Z of 0.77 is appropriate for all components of the stock. Recruitment to the offshore continues to be extremely low.

Complete document (PDF, 6163 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.