Sea lice infestations are prompting ongoing culling of farmed salmon in Tálknafjörður, though outbreaks have proven less severe in nearby Arnarfjörður and Dýrafjörður, RÚV reports. A veterinarian with the Icelandic Food and Veterinary Authority (MAST) has stated that treatments in the latter fjords have been effective, although colder winter temperatures, affecting the salmon’s ability to convalesce, pose challenges.
Sea lice in the southern Westfjords
The culling of farmed salmon severely damaged by sea lice is still ongoing in Tálknafjörður in the southern Westfjords. As noted in an article on RÚV yesterday, there has also been an excessive presence of sea lice in the nearby fjords of Arnarfjörður and Dýrafjörður. In one area of Arnarfjörður, the salmon are beginning to show signs of lice-induced lesions.
Veterinarian Berglind Helga Bergsdóttir from the Icelandic Food and Veterinary Authority (MAST) does not consider the situation dire enough to necessitate culling. “The situation is much better in both Arnarfjörður and Dýrafjörður. It’s not really comparable,” Berglind told RÚV yesterday. In Arnarfjörður, lice cleansing with hot water has been completed and has proven effective. Elsewhere in Arnarfjörður and in Dýrafjörður, medications are being used to rid the salmon of sea lice.
The treatment, however, is a race against time. As noted by RÚV, the intervention becomes more problematic for the fish as winter progresses. “All treatments lead to some degree of scale loss, and the healing and defences of the fish decrease with the lower sea temperatures,” Berglind concluded.
As noted in a press release from MAST in October: “Medications for sea lice can have negative effects on the ecosystems surrounding fish farms. Experience from neighbouring countries also shows that sea lice can develop resistance to drugs. Therefore, the use of medications in the fight against lice is a remedy that should not be applied except in absolute necessity. Consequently, the Icelandic Food and Veterinary Authority has encouraged companies to seek other methods to control lice infestations.”