Any lice with that salmon? Parasite plagues global industry

ST. ANDREWS, New Brunswick -- Salmon have a lousy problem, and the race to solve it is spanning the globe.

A surge of parasitic sea lice is disrupting salmon farms around the world. The tiny lice attach themselves to salmon and feed on them, killing or rendering them unsuitable for dinner tables.

Meanwhile, wholesale prices of salmon are way up, as high as 50 percent from last year. That means higher consumer prices for everything from salmon fillets and steaks to more expensive lox on bagels.

The lice are 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. Scientists and fish farmers are working on new ways to control the pests, which Fish Farmer Magazine stated last year costs the global aquaculture industry about $1 billion annually.

So far, it has been an uphill struggle that is a threat to a way of life in countries where salmon farming is a part of the culture.

Experts said defeating the lice will take a suite of new and established technology, 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.

Farmed salmon was worth nearly $12 billion in 2015, according to the Food and Agriculture Organization of the United Nations.

The only hope is to develop new methods to control the spread of lice, which are present in the wild but thrive in the tightly packed ocean pens for fish farming, said Shawn Robinson, a scientist with the Canadian Department of Fisheries and Oceans.

The lice can grow to about the size of a pea and lay thousands of eggs in their brief lifetime.

Atlantic salmon have held their own with sea lice in the wild for centuries, and fish farmers managed them in aquaculture environments for many years.

Farmers in Canada identified the lice as a problem around 1994, said Jonathan Carr, executive director of research and environment with the Atlantic Salmon Federation.

Feeding fish a pesticide with the active ingredient of emamectin benzoate became the tool of choice to control lice, Carr said.

But about 2009, the lice appeared to become resistant to the pesticide, and they have spread globally since.