The horizontal distribution of arctic cod in relation to the distribution of bottom temperatures in the Barents Sea, 1978-1984 [fra "a workshop on comparative biology, assessment and management of gadoids from the North Pacific and Atlantic oceans" 24-28 June, 1985 Seattle, Washington]

Abstract

The results from acoustic-trawl surveys in January-March were analyzed together with observations of bottom temperatures at the same cruises. Estimates of abundance of cod within temperature intervals of one degree were calculated for each age group, and distributions of abundance on temperature were established. The analysis showed that the older age groups, fish aged 6 and 7 years, were consistently found in warmer water, i.e. farther west, than the younger fish. The variations in bottom temperatures of the distribution areas appeared to be larger for the younger fish, age group 1, than for the older age groups. Year to year variations of weighted mean bottom temperatures in the actual distribution areas of the various age groups were compared with corresponding variations in two fixed areas and in the Kola section. The comparison showed that the temperature variations in fixed locations only to a certain extent reflected the variations in the actual environmental conditions of the fish. The growth of the fish increased significantly during the period of observation coinciding with an increase in mean temperature of the distribution areas of the fish during the same period.