Salmons account for most of the finfishes produced in Canadian aquaculture. The Pacific region is the major contributor, possessing an aquaculture industry which produces more than half of all finfishes grown in Canada. In 1997, British Columbia produced over 40,750 tonnes of finfish of which 40,550 tonnes were salmon!
Salmon hatcheries have been in use in the Pacific region for over 100 years. The hatcheries were built to aid in rebuilding the natural populations by releasing young fry into streams and tributaries. As a result, many salmon populations in the Pacific northwest are composed largely of hatchery fish. Longheld beliefs that such practices could only benefit the fish stocks has been challenged by recent studies on the demographic, ecological and genetic impacts that hatchery fish have had on wild populations. The deleterious effects have been attributed to the reduced genetic diversity, altered behaviour and altered physiology of the hatchery fish. With a the high demand for salmon and the strain on the wild populations, researchers are working to improve the quality of salmon aquaculture while removing the negative impacts on wild populations.