Loch Duart explores use of kelp hides in salmon farming
A new GBP 125,000 (USD 166,000, EUR 147,000) funding package has been granted by the U.K. Seafood Innovation Fund (SIF) for a company to explore the benefits of using natural kelp hides on fish farms.
Deployed in various sizes from one to nine meters in diameter, using a mix of naturally seeded and lab-grown kelp, KelpRings have been designed by Isle of Skye, Scotland-based KelpRing to offer a close as possible of an environment to what the cleanerfish ballan wrasse and lumpfish would experience in the wild.
The research will see KelpRings deployed at one of Loch Duart’s salmon farms for the next 18 months, as an alternative to the artificial seaweed hides typically used on fish farms. Additional support is being provided by the Sustainable Aquaculture Innovation Centre (SAIC) and the University of Stirling’s Institute of Aquaculture.
The trial will see Institute of Aquaculture researchers evaluate the impact of KelpRings against current standard conditions, assessing the preference of cleanerfish and mapping behavioral and physiological changes in the cleanerfish population related to their welfare. They will be also looking at cleanerfish efficiency by means of sea lice counts and the health and welfare state of salmon.
“Cleanerfish are naturally drawn to seaweed forests and by adding kelp hides to salmon pens, it allows the fish to act as they would in the wild, in their natural habitat. Wrasse and lumpfish can live a long and healthy life of up to 25 years if the conditions are right, and measures to enhance their wellbeing can only support their ability to treat sea lice,” KelpRing Founder Martin Welch said. “So far, the aquaculture sector has been incredibly positive about the prospects of using the system and we’re hopeful that the results from this latest trial will prove our hypothesis, with the kelp having a positive impact on Loch Duart’s cleanerfish population and a reduction in sea lice numbers.”
Loch Duart Cleanerfish Manager Lewis Bennett said he is of the opinion that the use of cleanerfish is the biggest innovation at Loch Duart.
“They play a vital and valuable role in the business, where they contribute to the fish health strategy. They are also a form of multitrophic farming incorporated into our salmon operations, where they keep our salmon free of sea lice, and we work to meet all of their requirements,” he said. “Being able to express their natural grazing behavior requires a range of factors to be met, such as having a habitat or structure in close proximity. We currently use artificial kelp for this, but being able to provide our wrasse with a more appropriate habitat should create a happier fish population and would reduce the need for artificial products. I am very keen to see the results on fish behavior but also the operational benefits of a habitat that doesn’t need cleaning or regular removal from the pen. As we have seen at Loch Duart across a range of factors, a natural option is always superior.”
A previous feasibility study with producer Scottish Sea Farms, combined with international research, showed the introduction of natural kelp on salmon farms can have medicinal properties and a calming effect on cleanerfish, boosting their ability to treat sea lice.
Photo courtesy of Loch Duart