Campaigners are contemplating legal action alleging animal cruelty after a video showed farmed salmon being deloused by a floating washing machine.
They say a boat caught on camera sucking caged salmon from a Highland loch to remove an infestation of sea lice with warm water is a “torture chamber” which leaves some dead.
The fish farm, however, argues that removing lice protects fish welfare. The treatment only last 30 seconds and the vast majority of salmon survive, it says.
Video by campaigners
Thermolicers pump salmon through tubes to a machine that washes them in water between 30 and 34 degrees centigrade, some 20 degrees warmer than the loch water. The change in temperature is aimed at removing the lice without harming the salmon.
Recent scientific research also found that salmon exposed to water temperatures above 28 degrees centigrade behaved as if they were in pain. Marine and veterinary researchers in Norway observed fish swimming faster, crashing into tank walls and shaking their heads.
Many salmon die from other problems at fish farms, including diseases and algal blooms. The Ferret reported in July 2020 that over 10 million fish – 25,770 tonnes – died prematurely in 2019, with death rates quadrupling over the last 18 years.
Two environmental campaigners and local residents, Andrew Holder and Maggie Brotherston, filmed a thermolicer boat in action at a fish farm on Loch Creran, north of Oban, on 14 July. “The incidence of sea-lice on industrially farmed salmon is out of control,” they said.
“With chemicals and cleaner fish failing to control the sea-lice problem, industrial salmon farmers are, in desperation, turning to mechanical methods.”
They added: “This is a torture chamber for farmed salmon. The thermolicer subjects fish to unnatural high temperatures of up to 34 degrees centigrade. This can cause pain and injury.”
A specialist UK law firm, Advocates for Animals, is now assessing the lawfulness of thermal lice treatments and considering possible legal challenges. “From the photographic evidence we have seen it appears that there is a strong legal case to answer,” said the firm’s solicitor, Edie Bowles.
“Farmed salmon are afforded protection from “unnecessary suffering” under the Animal Health and Welfare (Scotland) Act 2006. The photographs we have seen indicate systemic and obvious pain and suffering.
“Welfare standards on salmon farms need to be improved in order to comply with the law.”
The Scottish animal campaigns charity, OneKind, argued that the video showed that thermolicers were “highly stressful” for farmed salmon. It was not only the high temperatures that were harmful, it suggested.
“Salmon are seen crowded together, propelled along tubes and then metal rollers,” said the group’s campaigner, Eve Massie.
“The crowding of the salmon seen before they enter the tubes is recognised as a harmful process because the fish are exposed to abrasive surfaces, which can cause them physical damage.”
The Scottish Greens called for a review of the salmon farming industry. “People are rightly upset when they see the conditions and methods used by industrial scale fish farming,” said the party’s environment spokesperson, Mark Ruskell MSP.
“The figures we obtained from the Scottish Government show just how many salmon die as a result of this approach. But it also undermines Scotland’s reputation for good food and a clean environment.”
The Loch Creran salmon farm is run by Scottish Sea Farms. The company responded to criticisms on social media by saying that thermolicing used no additives and the lice were “disposed of responsibly on land”.
The company confirmed to The Ferret that the video showed thermolicer treatment on Loch Creran. Its head of fish health, Dr Ralph Bickerdike, had been present at the time.
“Proactive health treatments such as these are carried out specifically to protect fish welfare, removing lice just as is done with other farmed livestock,” he said.
“The treatment system itself was carefully designed from the outset to minimise handling and duration, with fish passing through lukewarm water for just 30 seconds and monitored closely throughout.”
Bickerdike added: “In this particular instance, the treatment successfully delivered 97 per cent clearance of lice with 99.8 per cent fish survival, demonstrating that, just like vaccinations of cats and dogs, the long-term health and welfare benefits outweigh potential short-term discomfort.”
He pointed out that water temperature was “fined-tuned” before every treatment to balance optimal removal of sea lice with fish welfare. “The upper limit of 34 degree centigrade was informed by work published by the Norwegian Institute for Marine Research showing that exposing 2.5-3 kilogram salmon to seawater up to 34 degrees for a maximum of 30 seconds did not cause undue harm or stress,” he said.
Cover image and video thanks to Andrew Holder and Maggie Brotherston.