A plague of parasitic sea lice has spread through salmon farms globally, causing an estimated $1 billion in losses and sending prices of farm-raised salmon up 50 percent, according to the Washington Post. “The lice are actually tiny crustaceans that have infested salmon farms in the U.S., Canada, Scotland, Norway and Chile, major suppliers of the high-protein, heart-healthy fish,” the Post said. As a result, the industry has contracted by about 10 percent.
To combat the lice, the industry is trying a number of different measures, “including older management tools, such as pesticides, and newer strategies such as breeding for genetic resistance. The innovative solutions in use or development include bathing the salmon in warm water to remove lice and zapping the lice with underwater lasers.”
The Post said that the industry first fought the parasite with the active ingredient of emamectin benzoate, “but around 2009, the lice appeared to become resistant to the pesticide, and they have spread globally since.”
To keep the parasite from infecting wild salmon, “Norwegian farmers are looking to use new closed-in pens that resemble giant eggs instead of typical mesh pens,” the newspaper said. “Scottish farmers have deployed a device known as a Thermolicer to warm the water and detach the lice from fish. And farmers in North America and Europe are experimenting with using species of ‘cleaner fish’ to coexist with the salmon and eat the lice,” it reported.
“Research about farming salmon along with mussels, which researchers have found will eat larval sea lice, is underway. Underwater drones inhabit the other end of the technological spectrum, zapping lice with lasers to kill them. That technology was developed in Norway and has been used there and in Scotland,” it said.