Influences of Stock and Site on Growth and Mortality in the Blue Mussel (Mytilus edulis)

Reciprocal transfers of three blue mussel (Mytilus edulis) stocks among three rearing sites resulted in marked changes in growth, mortality, and maximum biomass. Results indicate that site differences were major determinants of the growth effects, while stock differences were chiefly responsible for the mortality effects. The overall effect on biomass and potential yield was approximately equally attributable to site and stock influences. The results have relevance to aquaculture and environmental assessment using mussels and illustrate genotypic responses that may be significant for fisheries management.