A comparison between three Atlantic salmon river stocks; using classical population genetics, differences in life history traits and performance in sea ranching

Characterisation of stocks is essential for fisheries and environmental management in order to conserve genetic diversity. However, classical populationgenetic methods frequently fail to document stock differences. In this paper we list a number of characters that were used to compare the performance of the offspring of three adjacent river stocks during the freshwater period in culture until release, and their returns as adults. The emphasis will be put on life history traits and their consequences for growth and fishing mortality. We also present data on polymorph isozyme variation between wild fish from the stocks. The overview indicate that it rnay be necessary to include a number of traits to differentiate between stocks