History

As indicated by their name, Atlantic salmon are native to the east coasts of Canada and the US as well as streams of other countries tributary to the Atlantic Ocean.  In their native range, they are a highly valued species.  Although there were some early attempts to release Atlantic salmon on the West Coast, most if not all Atlantic salmon now in the wild are escapes from commercial net pen aquaculture facilities operated in Washington and British Columbia.  Well over 1 million Atlantic salmon have escaped from net pens as a result of storm events, equipment malfunction, vandalism, or predators (seals, sea lions) tearing at the netting.  In 1990, for example, the industry reported that 3.7% of farmed fish escaped. 

Photo courtesy of Huon Aquaculture

 Threat

Escaped Atlantic salmon have been documented to successfully reproduce in numerous streams on Vancouver Island, British Columbia.  These fish compete with native salmon and steelhead for spawning and rearing habitat as well as food resources.  Atlantic salmon that have escaped from aquaculture facilities also may be carriers of disease and parasites that infect native fisheries.   

Management Implications 

A report by the David Suzuki Foundation noted that anglers in southwest British Columbia waters have caught more than 18,000 Atlantic salmon while 556 have been caught in Alaskan waters.  Numerous streams on Vancouver Island now support populations of Atlantic salmon although data on population trends mostly are lacking.  The aquaculture industry claims that improvements in equipment and oversight have reduced escapes, but accidents, storms and predators continue to release fish to the detriment of native fisheries.  

References

Atlantic Salmon Watch Program.  A research program operated by Fisheries and Oceans Canada in cooperation with the states of Alaska and Washington and available online at www.pac.dfo-mpo.gc.ca/sci/aqua/ASWP_e.htm