'The risk come next year', anglers warn, as they reel in hundreds of farmed fish after Mowi escape

Calls were made to fine corporate giant Mowi after 75,000 farmed fish escaped enclosures in the north of Loch Linnhe, near Fort William, during Storm Amy earlier this month.

Gales of up to 90mph in the first named storm of the season shifted mooring anchors that breached pen nets at the farm, leading to the escape incident.

Activists and anglers have raised concern about the impact the escapees could have on Scotland’s endangered wild Atlantic salmon populations from interbreeding.

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Mowi has repeatedly denied claims the farmed fish will cause damage.

John Gibb, director of the Lochaber District Salmon Fishery Board, who has reeled in more than 300 farmed fish across the Lochaber river network in the past few days, said while the commercially-raised fish were unlikely to cause problems at the moment, there could be risk to them next year.

“At the moment these are immature fish, so they can’t spawn right now,” Mr Gibb told The Scotsman. “It will be next year by the time we find out if they’ve spawned with the wild fish, which would mean weakening the wild Atlantic salmon gene.

“The wild salmon have spent thousands of years acclimatising perfectly. These farmed fish have been bread to be fast growing and have a high fat content - what the consumer wants - and that’s nothing to do with nature.

“That’s what worries us as fishery managers.”

Mr Gibb said a focused effort by anglers on the surrounding rivers was ongoing to catch the escapees to minimise impact.

The angler, who is also fishery manager on the nearby River Lochy, said the bulk that were being caught were local to Loch Linnhe.

He said: "It was such a huge number that escaped, you’d expect to find a reasonable number to be caught. But these fish are technically in their marine phase, which means in nature they should be out at sea. The majority have gone out to sea."

Although believed to be the biggest escape incident, it is not the first. Some 50,000 fish escaped from a farm at Carradale, in Argyll and Bute, during another named weather event, Storm Ellen, in 2020.

Mowi funded work to discover whether the fish had interbred with the wild population. The company found the escape had almost no detectable impact.

Mr Gibb said Mowi had been co-operative by reporting the latest incident to fisheries boards “straight away” and the company would be involved in ongoing monitoring.

Next year, with the fish growing bigger after having 12 months at sea, it will be more challenging to tell the difference between the farmed and the wild fish by simply looking at them, Mr Gibb said.

“The only way you can tell is take a scale sample, send it off to genetics department at UHI Inverness and they will tell us whether it’s farmed or not,” he said. “So we will 100 per cent be able to tell next year whether these fish are spawning with the wild fish.

“Obviously the whole thing just shouldn’t have happened.”

Davy Gunn, an angler in the area, said he had dispatched nearly 30 farmed fish from two rivers in two days.

Posting online about his find, Mr Gunn said: “They are in every Lochaber river and down Loch Linnhe. It’s a sickening task dispatching these poor fish and burying them.”

The latest Mowi escape incident is understood to be the biggest yet in Scotland, bringing the company’s overall escape toll to half a million since 2000.

A spokesperson for Mowi said: “Mowi continues to work closely with the Lochaber District Salmon Fishery Board on this matter.”