The weird and wonderful monstrous machine above is a Thermolicer, the incredible secret bullet that the fish farming industry has bought to deal with the menace from sea lice. Judging by recent reports there are some problems with it:
Here are some (Soon to be)
Frequently asked Questions
The industry may have bought the machine, but who paid for it?
Perhaps we did!
Here is part of a news release from last October:
The drive to reduce sea lice and increase harvests of Scottish salmon has received a £1.76m boost, following a successful application to the European Maritime Fisheries Fund (EMFF).
Coordinated by the Scottish Aquaculture Innovation Centre (SAIC) on behalf of 11 companies, the award will enable a range of alternative technologies and approaches to be trialled in Scottish waters so that they can be evaluated for their ability to reduce sea lice – a naturally occurring parasite that affects farmed fish, costing the global industry over $1bn each year.
Says SAIC CEO Heather Jones: “The technologies being explored are capital intensive and their outcomes in Scottish waters are as yet unknown, therefore the financial and operational risks to industry are significant. By reducing those risks, this EMFF award will help catalyse trials on a commercial scale as opposed to an ad hoc or local basis.”
It’s not just the companies involved in the supported projects that stand to benefit. As part of the EMFF award, SAIC will commission a research project to capture the lessons learned, and share best practice with the wider sector and supply chain. There is also the potential to develop next generation technology for sale at home and abroad.
Amongst the alternative solutions being trialled is hydrolicer technology which uses low pressure water jets to dislodge sea lice; an innovative ‘bundle’ of technologies that brings best practice approaches into a single system; and a Thermolicer device which capitalises on the parasite’s low tolerance to sudden changes in temperature by briefly bathing fish in warmer water.
Comments Jim Gallagher, Managing Director of Scottish Sea Farms and one of the partners involved in the Thermolicer trials: “Everyone is clear on the real and urgent need to reduce sea lice. However significant capital investment is required to trial new solutions. The EMFF award is contributing additional resources to those invested by industry, enabling Scottish trials on a commercial scale. The new equipment will be accessible by many companies in Scotland’s salmon sector, supporting the industry’s common purpose in accelerating the widespread adoption of effective sea lice controls.”
So, how does the Thermolicer work?
According to the manufacturers Steinsvik
"The Thermolicer is a machine for commercial scale dip or bath treatment of fish. A sudden rise in water temperature is a well-known method of killing lice. We have developed a machine that does this on a commercial scale.
The fish are crowded and pumped into the machine where it passes through the processing loop in 25–30 seconds. Treatment water holds 30–34 degrees depending on ambient sea temperature. The treatment water is filtered, aerated, oxygenated and reused in the system. This simple and environmentally friendly treatment has an effect that goes beyond the expected in traditional treatment agents like chemicals and medicines."
If it's so terribly good, why did it kill the fish?
You will see from the BBC report reference to the fish suffering from Amoebic Gill Disease. The Thermolicer is of course not a treatment for AGD, so it seems likely that the fish had the disease and were also infested with sea lice. This is fairly common, because AGD, a sort of fish breathing disease weakens its victims and makes them more likely to be compromised by sea lice. Correspondingly, sea lice infested fish are bound to be weaker and more susceptible to disease.
34 degrees is the temperature at which sealice die, but it seems to have been simply too hot for its patients.
What is the maximum temperature which a salmon can endure?
Like most “cold-blooded” animals, salmon have little ability to regulate their internal temperature, so their body temperature is usually very close to that of the surrounding environment.
Research a few years ago Steinhousen et al and Eliason et al showed that salmon acclimatised to European water temperatures of a maximum of about 12 degrees began to show cardiac issues at temperatures above 21 degrees. Ambient water temperature in Scotland is rarely much above 8 degrees, so one can only guess the impact of a sudden increase to four times that. It seems likely that even healthy fish would be at risk of being compromised.
Does anybody care about whether or not the salmon suffer, being heated to four times what they're used to?
Seemingly not!
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