Variability among populations of wild and farmed Atlantic salmon - morphology and genetics

Morphological comparisons of farmed and wild stocks of Atlantic salmon have shown that it is possible to discriminate between stocks by using morphological characters. We will use this method to characterise juvenile Atlantic salmon in wild populations th at experience different intrusion rates of farm escaped salmon. We will also compare populations of Atlantic salmon that are reared for conservation purposes in the Live Gene Bank for salmon with their wild population of origin. Our objective is to test i f wild Atlantic salmon are affected morphologically by escapes. Morphological classification of individuals will be checked with a genetically-based assignment test using single nucleotide polymorphisms. We want to use these methods: 1. Morphological ch aracters - a pronounced morphological variability has been shown to exist between wild and farmed populations. This variability may have energetic consequences for the salmon and these differences in morphology can yield a more optimal farmed salmon. We i ntend to determine morphological variation in a wide variety of different populations and strains. 2. Genetic variation -analyses of Single Nucleotide Polymorphism markers (SNPs) will be used to examine concordance between morphological classification of juvenile salmon and genetic assignment to wild or farm origin. Finally, the morphology and genetics data will be synthesized in an analysis to assess the degree of genetic interaction between farmed and wild salmon in rivers having different levels of i ntrusions of farmed salmon.