Details of the largest mass escape of farmed salmon in the last ten years, in which some 80,000 individual farmed salmon escaped into the Scottish wilds, are only now emerging, despite taking place almost two years ago.

The ‘significant environmental incident’ – which now stands to threaten Scotland’s waters and wild fish populations – has only now come to light for the general public following a Freedom of Information request lodged by the investigations team at the UK-based environmental campaigning outfit, Green Britain Foundation.

The mass escape took place in February 2023 during the transportation of some 80,000 salmon smolts from Loch Shin. Yet, while the event marks the largest mass escape of its kind in the last decade, it had – until now – gone unreported to the public, raising serious questions over the transparency issues at Scottish government level.

The major incident, which campaigners say poses a severe risk of damaging Scotland’s endangered wild Atlantic salmon, only came to light due to a critical gap in official reporting mechanisms. 

Dale Vince, founder of the Green Britain Foundation, said: “This massive escape is a wake-up call for the damaging industry. For them, it’s about lost profit but for the rest of us it’s about the very real threat to our delicate marine ecosystems. 

“The fact that such a significant incident could go unreported for so long exposes dangerous blind spots in our environmental monitoring systems.”

Responding to calls upon the Freedom of Information act made by the Green Britain Foundation, the Scottish Government shared details of the previously unreported escape. The 80,000 salmon smolts, all of which were around 12 months old, were being transported by the Canadian-owned Cooke Scotland from Loch Shin. The fish were able to escape in transit via an unsecured hatch Cooke Scotland have put down to ‘human error’.

While such incidents have occurred before, few have been on such a scale. Meanwhile, officials only record escapes linked to specific farm sites. Because the escape took place during transportation, the obligation to report the incident falls outside of the official monitoring framework. It’s this loophole which has allowed one of Scotland’s largest salmon escapes to go unnoticed for nearly two years.

“This incident underscores the urgent need for a complete reassessment of how we monitor and regulate the salmon farming industry,” said Vince. “The health of our oceans and the integrity of our endangered wild salmon populations are at stake.”

The escape raises some serious environmental concerns, particularly regarding the potential for hybridisation between farmed and endangered wild Atlantic salmon populations. Research has previously shown that escaped farmed salmon can successfully breed with wild salmon, altering the genetic makeup of wild populations.

In a recent debate at the House of Lords, Lord Forsyth of Drumlean addressed such concerns when he said: “Escapees bring diseases to the wild population and whole rivers have been cleaned out of wild fish.”

He further argued that salmon farming has “resulted in environmental damage to wild fish populations and threatened other species.”

In an email exchange with the Green Britain Foundation, Lorna Munro, the epidemiology data manager for the Scottish government’s marine directorate, said the government is “currently considering the issue of reporting and transparency further.”

It’s a stance that has been met with disbelief by the campaigner behind the exposé who, in a written statement, said “the fact that officials are only considering changes to reporting requirements nearly two years after such a significant escape occurred is deeply concerning.”

What’s more, the campaign team positions that the escape ‘starkly contradicts’ recent salon industry assertions. In October, Ben Hadfield, the ceo of Mowi – a leading supplier of farm-raised salmon – told a Scottish Government Inquiry that “escape levels have dropped massively – to one fish, out of all the fish held in Scotland.”

The Green Britain Foundation has suggested that the recent revelation casts serious questions over the accuracy of industry-provided information. The Foundation is now, therefore, demanding an immediate revision of the reporting requirements, to include all salmon escapes, regardless of their location; the implementation of stricter regulations for fish transport and containment; and comprehensive environmental impact assessments of all aspects of salmon farming operations.

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