Seasonal changes in zooplankton composition in the Barents Sea, with special attention to Calanus spp. (Copepoda)

The Barents Sea is an important area with respect to fisheries resources (i.e. capelin and cod). In May, June and August 1981 zooplankton biomass was measured along a transect at 30°E, from the ice border southwards. A maximum was recorded in Atlantic water by the end of June (>100 g wet weight m−2 In August the biomass values were relatively low south of the Polar front and increased northwards into Arctic water (−50 g m−2 The species composition was influenced by the distribution of cold Arctic water and warmer Atlantic water. The zooplankton was dominated by the copepods Calanus finmarchicus and C. glacialis; the former is regarded as an Atlantic species and C. glacialis as an Arctic species.