‘Thermolicer’ makes a bid to tackle salmon farm scourge

The latest round in the salmon industry’s battle against sea lice has seen Scottish Sea Farms (SSF) invest £4 million in the “Thermoliser” – the first of its kind to be used in Scotland.

SSF, which produces around a quarter of Shetland’s farmed salmon, has been trying out the innovative system which has already been used successfully in Norway.

The Thermolicer is one of the most environmentally friendly ways to kill lice and SFF will be using it as its second resort, after salmon are grown in cages which also contain cleaner fish like lumpsuckers.

According to SSF: “There is a clear aspiration to reduce the need for medicinal treatments in the fight against the naturally occurring parasite and SSF continue to make investments to achieve this.”

The Thermolicer arrived in the isles last week and the intention is that it will be available for hire to all salmon operations in Shetland. The knowledge gained from its operation will be passed on to SSF’s other operators in mainland Scotland.

The Thermolicer is mounted on the deck of a large well boat and involves pumping salmon through water warm enough to be fatal to the lice, but cause no harm to the salmon.

It uses no chemicals in the treatment, but relies on the louse’s low tolerance for changes in temperature to eradicate the parasite. It is described as a “simple and environmentally friendly” method that goes beyond the traditional treatments.

SSF head of fish health Ralph Bickerdike said: “Sea lice is a challenge for all fish farmers in most salmon producing areas. At Scottish Sea Farms we intend being part of the solution to this challenge.

“Our work with SAIC (Scottish Aquaculture Innovation Centre) and other industry partners in this area has already reaped huge benefits through our work with wrasse and lumpfish – varieties of cleaner fish.

“The Thermolicer is the latest step in developing alternative tools to maintain a sustainable solution to fish health management.”

SAIC chief executive Heather Jones said: “We are delighted to see this level of innovation and collaboration happening in Scotland.

“The industry is tackling the biological issues it faces with energy and initiative, and with a strong commitment to sustainable practices.

“Scottish Sea Farms is leading the way, allowing the learning from deploying this new equipment being trialed to be shared with other operators in Shetland.”

Scottish Salmon Producers Organisation chief executive Scott Landsburgh said: “Scotland’s salmon farmers have always been at the forefront of new inventions creating technological solutions as needs have evolved.

“Collaboration and sharing knowledge and skills have been paramount in enhancing fish welfare. It also reinforces our commitment to environmental and industry sustainability – crucial in driving our industry forward.

“We look forward to hearing the results and seeing how it can integrate with established health management strategies to the benefit of the whole industry.”