December 12, 2024

Lice outbreaks due to salmon farms in Norway have substantial impact on wild fish, report states

Dense populations of salmon in fish farms along Norway's coastline cause lice outbreaks that affect wild fish more than is desirable, according to a report from a group of experts.

Norway regulates the growth of salmon farming to limit the impact on wild fish of lice, a parasite that feeds on the skin, mucus, and blood of the fish, with the potential to leave large wounds.

The majority of Norway's 13 production areas have high or moderate risks, the government said on December 5, citing the findings of the experts. The report forms part of the initial assessment of whether salmon production should be reduced in the different farming zones or permitted to increase, with a decision made every other year.

Norway makes up more than half of global farmed supply, benefiting from favorable conditions along its fjords and coastline that are difficult to replicate elsewhere.

"With the hot summer this year, we were prepared that the lice impact would be higher in northern Norway than in previous years," Fisheries and Oceans Minister Marianne Sivertsen Naess said in the statement. "It is nevertheless worrying that the wild salmon in the vast majority of production areas is moderately affected by salmon lice."

The report indicated a high risk of lice in the zone near Bergen on the west coast, while the risk is moderate in eight other areas. There's a low to moderate risk in the area near Vesteralen in the north and a low risk in three other areas.

- Bloomberg