What is the potential environmental impact of escaped salmon?
Salmon farming is a young activity — the first fish were harvested in the early 1970s — and there is no substantial genetic difference between the farmed and the wild fish. Relatively few generations, about five, have been completed within modern enclosed farming systems. The farmed salmon genome is composed entirely of naturally occurring genes also found in wild salmon. Captive breeding has resulted in the ability to select for naturally occurring characteristics that suit salmon farming, for example faster growth growth rates, but even the combination of selective breeding and ideal growth conditions only achieves a difference of a few months between farmed salmon and the fastest growing wild salmon. The genetic map of a farmed salmon and a wild salmon are indistinguishable. However, the behaviour of farmed and wild salmon are different. The wild fish is a predatory animal while farmed salmon are used to being fed on a regular basis. That is a disadvantage for the farmed fish if it
