Interactions of Atlantic salmon in the Pacific northwest IV. Impacts on the local ecosystems

The paper begins with the introduction of Atlantic salmon into the local ecosystems of the Pacific Northwest (Puget Sound), and describes potential interactions with native salmonids. Specific sections review possible hybridization between Atlantic and Pacific salmon, genetic dilution and alteration of the gene pool, the colonization of the aquatic environment by Atlantic salmon, and finally the interactions of wild salmon and genetically altered transgenics. This is followed by possible epidemics and transmission of waterborne disease, and reviews the potential for cultured Atlantic salmon, a non-native species, to introduce new diseases into the local ecosystem. There are nine specific items, from the diseases which might be involved, to potential interactions, and current policies for disease control. After a review of the potential ecological impacts in the Pacific Northwest, specifically the interaction with Pacific salmon and predation, there are three parts on the effects of artificial propagation practices in the region in general, the impacts of the introduction of various non-indigenous salmonid species, and a comparison of escapes or releases of propagated Atlantic and Pacific salmon. The last part examines the potential effects of Atlantic salmon vis-a-vis the Biological Status Reviews of west coast Pacific salmon stocks carried out by the National Marine Fisheries Service. The review ends by summarizing the varying degrees of risk carried by these issues.