Changing surface conditions in sea-cages to prevent parasite infections

Amoebic gill disease and salmon lice are among some of the greatest challenges the Norwegian Atlantic salmon farming industry faces. Manipulating surface conditions and pushing fish down beneath the surface layers with the highest infestation pressures could potentially control and prevent infestations. Dr. Daniel Wright from the Institute of Marine Research tested if a permanent freshwater surface layer in snorkel sea-cages can reduce amoebic gill disease and salmon lice levels compared to standard commercial cages. While freshwater surface layers were unable to prevent or reduce AGD and lice infestations, further research should test if other behavioural and environmental manipulations can be used to prevent parasites from infesting farmed salmon.