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Providing evidence to improve practice

Action: Deter birds from landing on shellfish culture gear using spikes on oyster cages Bird Conservation

Key messages

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A replicated and controlled study from Canada found that significantly fewer birds landed on oyster cages with spikes attached, compared to control cages.


Supporting evidence from individual studies


A replicated and controlled experiment in summer and autumn 2006 and 2007 in oyster Crassostrea virginica farms off the coast of New Brunswick, Canada (Comeau et al. 2009), found that ‘AntiCormo’ devices (spikes attached to oyster cage floats) significantly reduced the number of birds roosting on oyster cages (0-1.3 birds/100 cages at one site with AnitCormo cages; 0-42 birds at a second vs. 100-499 birds/100 cages at a control farm). Five species were seen on oyster cages (double-crested cormorants Phalacrocorax auritus, herring gull Larus argentatus, great black-backed gull L. marinus, common tern Sterna hirundo and great blue heron Ardea herodias).


Referenced papers

Please cite as:

Williams, D.R., Child, M.F., Dicks, L.V., Ockendon, N., Pople, R.G., Showler, D.A., Walsh, J.C., zu Ermgassen, E.K.H.J. & Sutherland, W.J. (2019) Bird Conservation. Pages 141-290 in: W.J. Sutherland, L.V. Dicks, N. Ockendon, S.O. Petrovan & R.K. Smith (eds) What Works in Conservation 2019. Open Book Publishers, Cambridge, UK.