Journal article

Sea lice infestation level alters salmon swimming depth in sea-cages

Samantha Bui, Frode Oppedal, Lars Stien, Tim Dempster



Host-parasite systems are often characterised by a co-evolutionary arms race, with avoidance behaviour being the first line of defence for hosts. In aquatic ecosystems, the rapid rise of fish farming has elevated host abundance, altering the context of host-parasite interactions. Behavioural defences in host fish may adapt to combat infection pressure in the captive environment. We tested whether farmed Atlantic salmon Salmo salar altered their swimming depth in response to the ectoparasitic sea louse Lepeophtheirus salmonis. Parasite loads were manipulated on individual fish, which were implanted with internal tags that recorded swimming depth. During daylight hours, salmon exhibited identi..

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University of Melbourne Researchers


Awarded by Norwegian Seafood Research Fund grant

Funding Acknowledgements

We thank Pascal Klebert (SINTEF) for providing the DST tags, and Jan Erik Fosseidengen, Gunnar Didriksen and Velemir Nola at Austevoll Research Farm (IMR, Norway) for their technical support. We thank Ben Phillips (University of Melbourne) for his comments on the manuscript. Funding was provided by a Norwegian Seafood Research Fund grant (F.O., L.S. and T.D., 900884) and an Australian Research Council Future Fellowship grant (T.D.).