Shooting and fishing: Fish farms are killing off our rivers

IT IS NOW PRETTY WELL ACCEPTED that lice from fish farms have been the death of the west coast sea trout fishery and have not done the salmon much good either. The great irony, it now emerges, is that the people who have most benefited from fish farming are the local estates, which usually own both the salmon and sea trout fishing rights as well as the land, quays and jetties that fish farm operators need for their operations.

So, while they have been letting their fishing to an increasingly dispirited band of anglers, the same estate-owning riparian owners have as often as not been raking it in from the rents they can charge the fish farmers.

Now it is perfectly true that when this fish farm malarkey started more than 20 years ago no-one fully understood the long-term effects of tinkering with the environment. Fish farming seemed a terrific wheeze. Here was a pioneering industry to prop up a failing Highland economy. Trebles all round.

Indeed, the relationship between farmed fish and wild fish was so little understood that river owners and fish farms connived to let out a few farmed fish to bolster catches.

However, now we know that salmon farming and wild fish don't mix, you have to wonder whether it is wise of estates to keep taking the fish farmers' coin in the full knowledge they are helping destroy the stocks of wild salmon and sea trout.

Take, for instance, the River Aline in Morvern, Argyll. Sea trout numbers have plummeted since Ardtornish estate allowed a smolt farm in Loch Arienas for the production of juvenile salmon. This time it is not the sea lice that have done for the sea trout population but too much rich food.

The wild trout are so well fed thanks to the smolt farm feed pellets and nutrients from fish guano that they don't need to go to sea in search of food to return as sea trout. Instead, they get bigger and fatter, stay in the loch feeding under the cages and eat one another. No wonder the estate can boast a 16lb brown trout, double the size of the biggest previous catch.

Meanwhile, the odd thoroughbred sea trout still turns up and the estate has embarked on a salmon stocking regime. But the odd thing about all this is that one of the directors of Ardtornish estate, Hugh Raven, is also a director of the Government's Sustainability Commission, a director of The Soil Association Scotland and numerous other eco trusts and charities, and stood as a Labour MP.

It seems unlikely that Mr Raven could be unaware of the connection between salmon smolts and sea trout numbers, especially as his sister, the glass engraver Jane Raven, walks out, as granny used to say, with that nice Andrew Wallace, who runs both the Association of Scottish River & Fishery Management and the Association of Scottish Fishery Boards. "We believe that the whole issue of the siting of freshwater smolt farms needs to be addressed," Mr Wallace has said.

As we now know that smolts can be reared in artificial ponds and tanks on land rather than in lochs, there doesn't seem to be any reason, apart from the fact it is cheaper for the fish farm operator and lucrative for an estate, to keep smolt cages in lochs. But as the pragmatic Mr Raven puts it: "Aquaculture is increasingly going to supply the world's fish needs – we have to accept that, and work to make it sustainable."

Quite.

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