Coastal cod in Northern Norway

Abstract

Northeast Arctic cod dominates the Norwegian cod fisheries, but a significant part of the landings are Norwegian coastal cod. In the past, landings of coastal cod by Norway have been estimated to be ∼5% of the total international cod landings north of 62°N. In contrast to Northeast Arctic cod, the coastal cod is restricted mainly to fjords and coastal areas. The coastal cod is distinguished from Northeast Arctic cod by the growth zones of the otoliths, but there is often doubt about the classification. In 1980–1983, a research program on coastal cod in northern Norway was carried out. The program was concentrated on five major fjord systems. Sampling and tagging of cod was carried out on the spawning grounds during the spawning seasons. In addition, some tagging of immature fish was carried out on the coast in autumn. Northeast Arctic cod occurred only in low numbers on the fjord spawning grounds, usually <5% of the total. Samples of cod, mostly immature, from the coast generally contained a higher proportion of Northeast Arctic cod, between 5 and 25%. The coastal cod tend to return to the same spawning grounds year after year, but some leave the fjords during the feeding season. Problems of defining a stock are discussed. Although the relationship between Northeast Arctic cod and coastal cod is unclear, the regularity in the spawning in at least some of the fjords indicates that they contain populations which are, to a large extent, self sustained.