Tagging experiment results on cod in western Norway fjord areas

Abstract

During recent years, experiments with large scale release of artificially produced Q-group cod at locations in western Norway waters have been carried out with the aim ofincreaseing the cod catches. As the general knowledge of the cod biology in the release areas is rather poor, the effect of these releases on the cod stock size is still a matter of discussion. In 1981 and 1982 tagging of "wild" cod was carried out in two areas comparable to the experimental locations for artificially produced cod. In this paper migration and fishing pressure is discussed on the basis of recapture results from these tagging experiments. A preliminary comparison of results from the experiments on released artificially produced cod is made. The results indicate very limited migration away from the tagging seats; less than 30 n.miles. The recapture frequency was 32 and 40% in the two areas. The commercial catches of cod fram the main recapture areas are insignificant and thus indicate that the population sizes are very small.