Fishery and Biology of Atlantic Cod (Gadus morhua) off the Southwest Coast of Newfoundland

Abstract

Data collected from the fishery off the southwest coast of Newfoundland indicated a decrease in the proportions of larger and older cod in ICNAF Division 3Pn in recent years. Changes in total mortality rates in 3Pn and on Burgeo Bank have been attributed to fluctuations in total landings and effort. Decreased growth rates for the younger cod and increased followed by decreased growth for the older cod were attributed to increased food supply superimposed on decreased bottom temperatures. Cod from Burgeo Bank grow faster than those from 3Pn. Sizes caught by various types of inshore boats were similar but larger fish were caught in deeper water, in eastern rather than western localities, and in the latter part of the season. Peak spawning occurs in May. Males were predominant in longline catches and matured at an earlier age and smaller size than females. Fish in the 3Pn area matured earlier and at a smaller size than Burgeo Bank fish. Vertebral averages at different localities in the area were similar but averages have decreased in recent years. Limited data on weights and fecundity are presented. Results are discussed in light of the separation of West Newfoundland and Burgeo Bank stocks.