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Providing evidence to improve practice

Individual study: Effectiveness of shelters at reducing predation of common tern Sterna hirundo chicks by gulls Larus spp. at a nesting colony near Port Colborne, Ontario, Canada

Published source details

Burness G.P & Morris R.D. (1992) Shelters decrease gull predation on chicks at a common tern colony. Journal of Field Ornithology, 63, 186-189


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

Physically protect nests with individual exclosures/barriers or provide shelters for chicks of ground nesting seabirds Bird Conservation

A small before-and-after study in 1990 study on a breakwater in Lake Erie, Canada (Burness & Morris 1992) found that no common tern Sterna hirundo chicks were predated by herring gulls Larus argentatus or ring-billed gulls L. delawarensis over 12 days following the provision of small plywood shelters (two 12.5 x 25 cm rectangles attached to form a 10 cm high triangular shelter), compared with ten chicks being predated in the eight days between first hatching and shelter provision. A total of 29 chicks were studied, with 11 disappearing (six before shelter provision and five after) in addition to those predated.