Time-series data for a selection of forty fish species caught during the International Bottom Trawl Survey

Abstract

Relative abundance estimates of 40 fish species caught during the ICES coordinated International Bottom Trawl Survey are presented for the period 1970-1993. Trends in survey catches for eight commercial species are compared with total stock biomass estimates derived from stock assessment. In general, there is a remarkably good correspondence between these two independent parameters, suggesting that the survey is capable of registering significant changes in abundance. Among the 40 species, there are many more showing a positive trend during recent years than a negative one. However, the commercial species are all either declining or are stable. The most significant changes are observed in 'southern' species, which is probably related to a period of relatively warm winters after 1990. In many resident species, however, that appear to the increasing over a prolonged period of time, this explanation does not seem to apply.