Fine-mesh crowding net ‘can cut lice challenges in half’
A net that captures lice that fall off farmed salmon and trout when the fish are being crowded in a pen for treatment or harvesting may offer an economical way to reduce the problem of parasites.
The Norwegian-developed net, called catchLICE, is supplied by Kristiansand-based OK Marine and has been successfully tested by salmon farmer Bremnes Seashore.
“We found that catchLICE is gentle on the fish and collects significant amounts of lice - about twice as much as in conventional nets - which are very promising results and which can provide significant savings for the industry,” said Bremnes Seashore head of strategy and development Geir Magne Knutsen.
“It is important for the industry to get more tools in the toolbox, and catchLICE can be a very important product for the industry if the final results are as the preliminary results indicate.
“Removing lice from water has been a problem for a long time. When different types of handling are carried out or the fish must be harvested, nets are used that limit the space inside the cage and bring the fish together, but these nets do not eliminate the parasites that remain free in the water.”
OK Marine believes that using catchLICE eliminates the problem. The lice that fall off during crowding are caught in the net, and then removed by a lice filter on board treatment vessels.
“When the number of lice increases, lice quickly appear throughout the area. And then you have a problem,” said Knutsen.
“During the handling of fish, 50% of the lice can fall off the fish. If we can catch that 50% it will also reduce the need for treatments. In addition to the large savings the net will provide, it will also reduce waste and improve fish health significantly.”
The net has a mesh size of 2mm, which gives little scale loss for the fish during crowding.
Gentle on fish
“CatchLICE is gentle on the fish, and during handling it seems that the fish are calmer and less stressed than when using traditional nets,” said Knutsen.
OK Marine sales manager Inge F Salvesen is grateful for the good collaboration with Bremnes Seashore.
“CatchLICE has been under strong development over the past year, and many thanks go to Bremnes Seashore that took on the task of being at the front line with us to make the product mature for the market,” said Salvesen, who added that the salmon farmer’s participation had been crucial for the product.
The catchLICE net has been a development collaboration between Askvik Aqua, Bremnes Seashore, AKVA group - Egersund Net and OK Marine.