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Providing evidence to improve practice

Individual study: Underwater playback of chase-boat engines reduces common eider Somateria mollissima numbers at mussel Mytilus edulis farms on Loch Striven and Loch Creran, Argyll, Scotland

Published source details

Ross B.P., Lien J. & Furness R.W. (2001) Use of underwater playback to reduce the impact of eiders on mussel farms. ICES Journal of Marine Science, 58, 517-524


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

Scare birds from fish farms Bird Conservation

A controlled, replicated before-and-after experiment in January-April and October 1998, and March 1999, in Argyll, Scotland (Ross et al. 2001), found that an underwater playback system (UPS) was effective in deterring common eider Somateria mollissima from feeding on mussels Mytilus edulis at farms on two sea lochs (47-80% fewer birds feeding after use of the UPS; 2-37 birds feeding before use). Underwater recordings of an approaching ‘scare boat’ (scaring by boat being a conventional deterrent method) were played via an underwater loudspeaker, and also a ‘control’ i.e. playback of an unassociated sound. Average return time of eiders after chasing by boat also increased significantly, suggesting that effectiveness was strengthened by UPS.