Food and feeding habits of cod from the Balsfjord, northern Norway during a one-year period

The stomach contents of cod sampled by bottom trawl nine times in one year from three stations in the Balsfjord (69°N) were analysed. The possibility that the results were biased due to the cod feeding in the trawl net was discarded. In all 72 different animal taxa were recorded in the food. Of thes...

Full description

Bibliographic Details
Published in:ICES Journal of Marine Science
Main Author: Klemetsen, Anders
Format: Text
Language:English
Published: Oxford University Press 1982
Subjects:
Online Access:http://icesjms.oxfordjournals.org/cgi/content/short/40/2/101
https://doi.org/10.1093/icesjms/40.2.101
Description
Summary:The stomach contents of cod sampled by bottom trawl nine times in one year from three stations in the Balsfjord (69°N) were analysed. The possibility that the results were biased due to the cod feeding in the trawl net was discarded. In all 72 different animal taxa were recorded in the food. Of these 11 taxa made up the principal prey of cod in the fjord: deep water prawn Pandalus borealis , capelin Mallotus villosus , and small krill Thysanoessa spp. were the most important. The others were the polychaete Nephtys sp., the mysids Erythrops sp. and Michteimysis mixta , the amphipods Arrhis phyllonyx, Halirages fulvocinctus , and Rhachotropis macropus , the krill Meganycliphanes norvegica , and herring Clupea harengus . Krill was probably the only prey taken in midwater. The relative importance of the prey and also the diversity of food in the cod stomachs varied between the stations. Food diversity was lowest at the mid-fjord station. This was probably due to smaller environmental variations, a lesser edge effect, and less influence of adjacent prey communities on this large and deep trawling ground. The fullness of the stomachs showed no seasonal trend and was not consistent between stations. Neither spawning nor the polar darkness seemed to influence food intake.