Fears for wild salmon after one million fish escape from farms

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The Independent Online

Up to one million farmed salmon and sea trout escaped from their sea cages during the storms that ravaged Scotland last week, triggering fears that the country's remaining wild salmon stock could be wiped out.

Up to one million farmed salmon and sea trout escaped from their sea cages during the storms that ravaged Scotland last week, triggering fears that the country's remaining wild salmon stock could be wiped out.

Between 600,000 and a million farmed salmon and sea trout are believed to have escaped from cages which were ripped apart or sunk by 120mph winds and high seas.

Environmentalists fighting to secure tougher legislation governing fish farms are worried that the mass escape will have a detrimental affect on the remaining numbers of wild salmon in Scotland's rivers.

Opponents of fish farms estimate that up to 400,000 fish have escaped every year for the past five years but the force of last week's storms meant many more fish escaped at once.

"Official industry figures suggest that in excess of 600,000 salmon were lost," said a spokesman for the Scottish Executive yesterday. "Our advice from Fisheries Research Services suggests the losses include a significant number of mortalities and many more of those that got away will die."

Last year, 55,000 wild salmon were caught in Scotland and there are a number of rivers now believed to have fewer than 100 native salmon left.

"This is a disaster for Scotland's royal fish which are already under pressure from pollution and sea lice infestations from farmed fish," said Bruce Sandison, of the Salmon Farm Protest Group, which has been campaigning for the Scottish Executive to force fish farmers to move their business out of the sea and into land-based containment tanks.

He added: "A species which has existed in Scottish waters for 10,000 years since the end of the last ice age is on the verge of extinction."

Opponents of fish farms have long worried that escaped salmon were breeding with native wild fish and destroying the natural gene pool which had been built up over centuries.

Many fear that such a sudden influx of up to one million escaped fish will tip the balance of nature as they compete with wild salmon for habitat and a finite food supply.

"It is clear from last week's storms that the cages being used are inadequately designed for the purpose they are supposed to be built for," said Mr Sandison. "This was and is a disaster that is going to happen again until the Scottish Executive forces this industry ashore."

Fiona Cameron of the Sea Trout Group, which lobbies to minimise the adverse impact of fish farming on wild salmon and sea trout, said the escape could have a major impact on wild stocks. "If farmed fish go up salmon rivers they are likely to breed with wild salmon and the progeny will not be so successful," said Ms Cameron.

"Over time, the wild stock of a river could be completely wiped out as a result because each successive generation becomes less fit for the environment it finds itself in."

She added: "Wild salmon are specifically tailored for their environment. Stocks from an east coast river might not necessarily thrive if they were suddenly transplanted in a west coast river.

"If even just 1 per cent of these escaped fish make it upriver, where - in some areas - stocks have declined to such an extent there are less than about 100 native salmon, it would have a devastating affect."

There are more than 300 fish farms in Scotland, many of them using a series of circular or square metal-framed cages anchored in sheltered sea lochs which support conical shaped nets capable of holding tens of thousands of fish at a time.

Yesterday, Scottish Quality Salmon (SQS), an umbrella group for the industry, said that a significant number of the escaped fish had been recovered.

"Six pens thought damaged in the storms off Western Isles have been secured and all the fish contained in them are alive and well," said a spokesman.

"The extreme storm that hit Scotland last week has caused extensive damage across many sites and operations, with a number of our member companies reporting damage to pens, boats and other equipment. "This will undoubtedly cause significant business disruption, which, in turn, could impact on a number of rural businesses and the jobs and communities that depend upon them for their livelihood."

The SQS played down the impact that the escapes might have on wild salmon. "The majority of the fish in pens affected are likely to have died during the storms and at this time of year it is extremely unlikely that surviving fish will seek river spawning grounds, instead heading out to feeding grounds at sea," said the spokesman. "There is also clear evidence that many have been eaten by predators such as the large seal population on the Western Isles."