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Providing evidence to improve practice

Individual study: Use of cleaner- wrasse (Centrolabrus exoletus (L.)) and Ctenolabrus rupestris (L.)) to control infestations of Caligus elongatus Nordmann on farmed Atlantic salmon

Published source details

Tully O., Daly P., Lysaght S., Deady S. & Varian S.J.A. (1996) Use of cleaner- wrasse (Centrolabrus exoletus (L.)) and Ctenolabrus rupestris (L.)) to control infestations of Caligus elongatus Nordmann on farmed Atlantic salmon. Aquaculture, 142, 11-24


This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

Use natural control agents: cleaner wrasse Sustainable Aquaculture

In 1992, a replicated, controlled study in Ireland (Tully et al., 1996) found rockcook cleaner wrasse failed to consistently reduce numbers of lice, Caligus elongates, in sea-caged salmon, Salmo salar. When compared to control cages, the wrasse controlled infestation levels, preventing an outbreak on only one of the seven sampling periods. Each of five circular salmon cages (50-70m circumference, 10m depth) was stocked with between 13,000 and 24,000 salmon smolts. Wrasse were added to four cages at wrasse: salmon ratios between 1:37 and 1:49. Wrasse were not added to the control cage.