Fishing around for answer on restocking

You can’t help feeling that new attempts to restock Scottish rivers with salmon – hardly a novel concept – are very much a last throw of the dice. Previous river stocking efforts, with the notable exception of the west coast Carron, have met with limited if any success. Catches of wild salmon have crashed everywhere. Climate change, predation at sea, lack of food and of course west coast fish farm lice all play their part. So while many consider lice from fish farms a prime cause for the crash in west of Scotland salmon stocks, we have to hope the latest attempts at restocking, backed by the salmon farmers themselves, will produce something. Anything.

While a novel attempt by the local river board to restock the Lochy with the backing of seafood company Mowi (formerly Marine Harvest) is seen by critics as nothing less than a cynical PR wheeze by the world’s largest salmon farmer, it has to be better than doing nothing; sitting on the river bank wringing our hands and bemoaning the end of an era.

And at least the Lochy experiment is a new and untried approach to restocking. Instead of rearing smolts from the eggs of wild fish and sending them to sea, which is the traditional approach, 200-300 Lochy smolts will be netted in the river and grown on to maturity in specially dedicated Mowi cages at Lochailort.

The fully grown adults will then be reintroduced to the river to spawn in tributaries that have been rendered barren by the lack of returning adult fish. Their progeny, the thinking goes, will have retained their wild genetic integrity and give them a better chance of survival once they go to sea.

It is essentially a numbers game. Send more young fish to sea but with an inbuilt capacity for survival and at least some – or at least more than at present – will survive to return. Maybe.

There are other restocking projects afoot, backed by the salmon farming industry, each with slightly different approaches. The Scottish Salmon Company is working with the local estate to restock the Forsa on Mull. But so far only the Carron – again with fish farming industry support – can claim much success and that has taken years of dedicated work. Whether any success on the Lochy can be translated to suffering east coast rivers, unaffected after all by fish farms, is another matter.

And it will be two years before anyone can tell if the Lochy trial is worth scaling up. It would be ironic if wild Scottish salmon can be saved by the very industry largely blamed for its demise.