Tucked within Norway’s fjord-riddled coast, nearly 3,500 fish pens corral upwards of 400 million salmon and trout. Not only does the country raise and ship more salmonoid overseas than any other in the world (1.1 million tons in 2018), farmed salmon is Norway’s third largest export behind crude petroleum and natural gas. In a global industry expected to quintuple by 2050, farmed salmon is a fine kettle of fish.
But raising salmon is not without its challenges. Feeding them makes up half of all operational costs. Parasitic crustaceans called sea lice (Lepeophtheirus salmonis) make easy meals of captive fish, attaching to their bodies by suction and grazing on skin, blood and mucus.
If they don’t kill the fish, some delousing methods, such as flushing fish with water, might. About 15 percent of farmed salmon die in traditional fish pens and sea lice cost the salmon industry several billion dollars annually, according to Norway Royal Salmon. A new remote-controlled fish pen—the first of its kind designed for the tempestuous waters of the open ocean—could help Norway meet the growing demand for salmon and at the same time reduce the cost of feed and mortalities that result from sea lice.