West coast Vancouver Island Pacific cod assessment : Évaluation de la morue du Pacifique de la côte ouest de l'île de Vancouver en 2002

Two versions of a delay-difference assessment model were used to predict the response of the stock to varying fishing levels for the 2003/04 fishing year, one which used the shrimp trawl abundance data and the second which left out these data to maintain comparability with the 2001 assessment. [...] The shrimp trawl index for May 2002 was used directly as an abundance index for the 2002/03 fishing year in the assessment model which used the shrimp trawl data and the index was used indirectly to predict the 2002/03 CPUE index for the assessment model which did not use the shrimp trawl data. [...] Therefore, this paper, at the request of the fishing industry and the Canadian Groundfish Research and Conservation Society (CGRCS), has undertaken to repeat the previous assessment of Pacific cod on the west coast of Vancouver Island by updating the available data and including a new index of abundance. [...] For the at-sea samples, the catch weight was the weight of the catch of the bottom trawl tow from which the sample was drawn. [...] The model estimated the catch data, based on an effort series calculated from the CPUE index (Table 1), the mean population weight at the beginning of the fishing year and the shrimp trawl survey biomass index, which was also assumed to occur at the beginning of the fishing year.