The 1983 Pacific west coast bottom trawl survey of groundfish resources : estimates of distribution, abundance, age and length composition

The Northwest and Alaska Fisheries Center conducted a bottom trawl survey during July-October, 1983, the third in a series of triennial assessment surveys of Pacific whiting, Merluccius productus, and important continental shelf rockfish species (genus Sebastes). Two chartered bottom trawl vessels were deployed in the area from Monterey Bay, California to Estevan Point on Vancouver Island, British Columbia (lat. 36°48'N - 49°15'N). Bottom trawl hauls were attempted at 596 stations at depths of 55-366 meters (30-200 fathoms); 561 of these hauls were considered satisfactory. This report describes the sampling and analytical methods used and summarizes the data collected during the bottom trawl survey. The contents include temperature data, catch composition, distribution and relative abundance of major groundfish species, and rankings of fish species by International North Pacific Fisheries Commission (INPFC) areas and depth strata in terms of catch per unit effort. Biomass, population, and size composition estimates by INPFC area are presented for the more commercially important species. Additionally, estimates of age composition by INPFC area for Pacific whiting are included. Detailed haul and catch information and results of computer analyses are appended. 1984 NMFS (National Marine Fisheries Service) NWFSC (Northwest Fisheries Science Center) AFSC (Alaska Fisheries Science Center) Library Public Domain 1864