Coastal Cod and Skrei in the Lofoten Area

Abstract

1) Otolith samples and length measurement of cod taken in Lofoten during March-April 1960 and 1961 by long line/purse seine and Danish seine are studied together with the recaptures of cod tagged in the same years from catches taken by hand line/purse seine and Danish seine. 2) The cod in the otolith samples was splitted into skrei and coastal cod by the structure of the zones in the otoliths. The relative number of coastal cod in the Danish seine catches was 73-92 percent, while the content of coastal cod in the long line/purse seine catches was estimated to 9-11 percent. The dominating age groups among skrei and coastal cod were 9-11 and 5-7 respectively, and the older age groups among the coastal cod were more abundant in the population fished by long line/ purse seine than the population fished by Danish seine. 3) Both coastal cod and skrei were during spring and summer migrating out of Lofoten. A very small part of the coastal cod seems to migrate further north than 70° N, while the skrei spread into the northern waters from Bear Island and West Spitsbergen to the South-East Barents Sea. On the migration from Lofoten in the tagging year the coastal cod and the skrei seem to some extent to be separated, but as the coastal cod grow older they join the skrei shoals. 4) Considerable inroads have been made by the fishermen on both the coastal cod and the skrei present in Lofoten during March-April 1960 and 1961. While several nations have been fishing the skrei, the coastal cod has mainly been fished by Norwegian fishermen.