Journal article

Parasites under pressure: salmon lice have the capacity to adapt to depth-based preventions in aquaculture

Andrew Coates, Ben L Phillips, Frode Oppedal, Samantha Bui, Kathy Overton, Tim Dempster



The evolution of pesticide resistance has driven renewed interest in non-chemical pest controls in agriculture. Spatial manipulations (physical barriers and fallowing, for example) can be an effective method of prevention, but these too might impose selection and cause rapid adaptation in pests. In salmon aquaculture, various non-chemical approaches have emerged to combat parasitic salmon lice (Lepeophtheirus salmonis) – a major pest with clear signs of evolved chemical resistance. ‘Depth-based’ preventions, now widely implemented, reduce infestation rates by physically segregating salmon from lice in their infective copepodid stage occurring in surface waters. Copepodids distributed deeper ..

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Awarded by Research Council of Norway

Funding Acknowledgements

Funding was provided by the Research Council of Norway project "Environmental requirements and welfare indicators for new cage farming locations and systems" (Future Welfare, #267800) awarded to FO and TD. We thank staff at the Austevoll (Institute of Marine Research; IMR), Norway and Vindsvik (Mowi ASA), Norway, salmon farms for their on-site assistance with collection of salmon lice. We thank Tina Oldham, Lise Dyrhovden and Martin Peter Matre from IMR's Matre research station for assistance in louse collection, salmon husbandry and column construction. The use of salmon to rear lice was conducted in accordance with the laws and regulations controlling experiments and procedures on live animals in Norway (Animal ethics permit: FOTS ID 12935).