On our last day in Vancouver, an article in the Globe and Mail explored the controversy surrounding salmon farming in British Columbia. Initially met with enthusiasm by the conservation community, the small, experimental farms of the 1970s seemed to provide an answer to the decimation of the wild salmon population. But, as the farms have become large, mechanized facilities, a number of environmental concerns have been raised.
Canada ranks fourth in salmon aquaculture, behind Norway, Chile and the U.K., and about 60% of its farms are in British Columbia. Though some of the B.C. facilities raise Pacific salmon, most have switched to Atlantic salmon which adapt better to the aquaculture environment and tend to grow faster. The newest facilities can handle almost 1 million fish, adding to concerns about local pollution and the spread of disease (especially sea lice). In addition, since most of these farms use netting for containment, schools of salmon often escape, raising concerns that they will spread disease to wild populations and compete with the latter for food and spawning sites.
A potential solution to these environmental threats is the development of solid-wall holding tanks which will permit filtration of the sea water, provide a mechanism for waste control and eliminate the risk of escape. Of course, such structures would cost more to build and operate, increasing the market price of farm-raised salmon. Whether consumers will accept the cost of environmental protection is another matter.
