Temporal changes in harvesting dynamics of Canadian inshore fisheries for northern Atlantic cod, Gadus morhua

We quantified temporal changes in catch rate, fishing effort, and catch mis reporting for two sectors of the fixed-gear fishery for Newfoundland's nort hern Atlantic cod, Gadus morhua, from 1980 to 1991, the year preceding the stock's commercial fishing moratorium. Over the 12-year period, fishermen r eported catch rate declines of 40 and 75% in the trap and gillnet fisheries , respectively, associated with significant increases in nominal fishing ef fort. Additional changes to effort included smaller gillnet and trap mesh s izes, larger traps, longer soak times, and modifications to trap design to increase catch retention probabilities. Compared with the early 1980s, unre ported catches among inshore fishermen may have trebled by the late 1980s a nd early 1990s due to longer gillnet soak times, increased gear selectivity for small fish, and declining availability of fish of marketable size. The se patterns in harvesting dynamics are consistent with the hypothesis that the decline of northern cod was gradual and that increased rates of catch m isreporting contributed to increases in fishing mortality. The concomitants of declining fixed-gear catch rate, increasing quantitative and qualitativ e fishing effort, increased selectivity for smaller fish, and increasing le vels of unreported catches may represent general correlates of imminent fis h stock collapses.