On the geographical distribution of arctic cod in relation to the distribution of bottom temperatures in the Barents Sea, 1977-1984
1984
Nakken, Odd | Raknes, Askjell
The results from acoustic-trawl surveys in January-March were analysed together with observations of bottom temperatures at the same cruises. Distributions of fish abundance for each age group of cod on temperature were established. The analysis showed that the older age groups, fish aged 6 and 7 years, were consistently found in warmer waters, i.e. further to the west, than the younger fish, aged 1-3 years. The variations from year to year in bottom temperatures of the distribution areas appeared to be largest for the youngest fish, the l year olds, and considerably larger than the corresponding temperature variations in two fixed reference areas. The mean lengths at age 4, 5 and 6 years were observed to increase significantly for the yearclasses 1975-1980 and this increased growth coincided with an increase in mean temperature of the distribution areas of the fish.
显示更多 [+] 显示较少 [-]