Cultured salmonids are released or escape into the wild in large num

• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 2006
• Subjects: aquaculture; Atlantic salmon; competition; domestication; fisheries manage- ment; gene flow; maladaptation; migratory fish; population viability; Salmo salar; Norway
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.543.9591; http://icesjms.oxfordjournals.org/content/63/7/1234.full.pdf

ow nloaded from significant proportions of wild salmonid populations in fresh- and saltwater, causing consid-erable concern for the fitness and productivity of these populations. This paper focuses on the effects of escaped farmed Atlantic salmon (Salmo salar) on wild salmon. Farmed salmon have been under artificial selection for growth and other economically important traits for 30 years and are genetically different in their origin at the molecular and quanti-tative genetic levels. Escaped farmed salmon spawn in the wild with limited success. Their offspring outgrow those of wild origin but suffer higher mortality. Whole-river experiments in Ireland and Norway have shown that the lifetime success of farmed salmon is reduced relative to wild salmon. Based on data from these experiments, we model the future of wild salmon populations experiencing invasions of escaped farmed salmon. Simulations with a fixed intrusion rate of 20 % escaped farmed salmon at spawning suggest that substan-tial changes take place in wild salmon populations within ten salmon generations (w40 years). Low-invasion scenarios suggest that farmed offspring are unlikely to become estab-