Escape of a million farmed fish threatens wild salmon
By Severin Carrell
3rd August 2003
More than a million fish have escaped from fish farms over the past six years, threatening the survival of Britain's declining wild salmon populations.
The number of escapes - revealed by new government figures - has reinforced fears that farmed salmon are steadily killing off their wild counterparts by interbreeding, competing for food and by passing on infections.
The statistics also show that since 1999 at least 4.4 million salmon and trout have been killed in incidents involving poisonous growths of algae in the sea and invasions by jellyfish, including 1.9 million fish last year alone.
These figures, which exclude the millions of salmon and trout that die in cages each year from infectious diseases and parasites, have led to renewed criticisms about the treatment of farmed fish. At least seven mass escapes last year involved salmon from fish farms infected by a potentially fatal virus.
Conservationists link these escapes, caused by storms, broken cages and seals cutting open cages, and the regular outbreak of disease to a steep decline in wild salmon and trout populations in the north Atlantic. Wild salmon numbers have plunged from 12,000 tonnes caught in the mid-1970s to about 2,500 tonnes in 2000.
New research by Irish marine biologists has shown that young salmon created by the interbreeding of wild and farmed fish are dying out in the Atlantic before they can mate. These hybrids are also producing fewer young, suggesting that if cross-breeding continues, pure wild salmon will die out.
David Henderson, the Scottish director of the Salmon and Trout Association, said: "This research indicates that cross-breeding creates a non-viable strain.
"We totally deplore the fact that these escapes are allowed to happen. We think it's perfectly possible for the industry to avoid this by investing in cages that prevent escapes. We're tremendously worried that if these escapes continue, farmed fish might outnumber wild fish."
A spokesman for Scottish Quality Salmon, the main industry body in fish farming, admitted that escapes were the industry's "Achilles heel". He said: "They're not acceptable. We realise this is an issue.” He said fish farmers were trying to stem the losses by improving cage design.
Bruce Sandison, chairman of the Salmon Farm Protest Group, said: "These figures show the reality behind an industry that claims that its farmed fish come from clean, unpolluted waters. To prevent further damage to wild fish and the environment, this industry must be immediately brought ashore and conducted in land-based, closed-containment systems."
Scottish Quality Salmon insists that growing fish in land-based tanks would be economically disastrous, would take up large areas of land and be more polluting than doing it in the sea.
But the protest group argues that fish farmers are more concerned with profits than the environment. The industry has successfully persuaded the Government to delay introducing a new European Commission regulation that requires all fish killed by disease, accidents or parasites to be buried in licensed landfills rather than being recycled as animal feed or for cosmetics. The new regulation could cost up to £100m to implement, the industry claims.