Fishing lines: The fish farm debate has its hooks in us all

My daughter, Amber, has just forced herself to eat lashings of salmon in the cause of research. It was part of a GCSE food-technology project looking at whether we should be getting our fish from farms or the sea. Quite a mature choice, I thought. At 15, my project would have been to discover how many chips you can cram in your mouth.

My daughter, Amber, has just forced herself to eat lashings of salmon in the cause of research. It was part of a GCSE food-technology project looking at whether we should be getting our fish from farms or the sea. Quite a mature choice, I thought. At 15, my project would have been to discover how many chips you can cram in your mouth.

Amber's project included testing her classmates to see if they could tell the difference between wild and farmed salmon. In the process, the last of our fresh salmon disappeared; but I didn't grumble – much; the results were very interesting.

More than 80 per cent could identify the farmed fish: pretty good, considering that so few people get a chance to eat the proper stuff nowadays. Any salmon you buy will almost certainly be farmed. That applies to many other denizens of the fish-counter too. Turbot, halibut, bream, even cod are now grown down on the farm rather than out in the sea.

You may think this is a good thing because it answers a growing demand for fish. But fish farms generate pollution from their waste products. On Ireland's west coast, the evidence that a slump in sea trout numbers has been caused by fish farms is incontrovertible.

The Sunday Times Magazine recently ran a story taking nature's side. The front page, illustrated with a wedge of grilled salmon decorated with lemon grass, said: "Tasty? It should be. It's been dyed, disinfected and bred in a polluted, parasite-infected cage ... and they call it healthy food." Fish Farming International roared back like a caged salmon. Few things are more entertaining than two publications hitting each other with wet fish. But some of the replies from Scottish Quality Salmon were spurious.

Arguing against the statement that "wild salmon and sea trout are being driven inexorably towards extinction," it quotes a Worldwide Fund for Nature report that says: "90 per cent of the salmon populations are known to be healthy in four countries – Norway, Ireland, Iceland and Scotland. These are countries where salmon farming is an important industry taking pressure off wild salmon stocks." Yet earlier this year I read that Scottish wild-salmon stocks were at their lowest levels since records began.

Many of my acquaintances who go to Scotland for the the salmon season have returned with tales of woe. No fish. This is bad news for Scotland's tourist economy, because many of these anglers are considering switching to Ireland, where rivers like Blackwater and the Moy still get decent runs.

Although Fish Farming International argues that "salmon farming is an industry with much to offer Scotland: jobs, experts, reputation and fine quality salmon", its financial benefits are a pittance compared to what a good run of wild salmon generates.

A lot of my animosity towards fish farms is rooted in what salmon represent: salmon are the epitome of freedom; caging them is like locking an eagle in an aviary.