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Providing evidence to improve practice

Individual study: Nest shelters reduce weight loss in common eiders Somateria mollissima females on tundra in northeast Canada

Published source details

Fast P.L.F., Grant Gilchrist H. & Clark R.G. (2007) Experimental evaluation of nest shelter effects on weight loss in incubating common eiders Somateria mollissima. Journal of Avian Biology, 38, 205-213


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

Provide artificial nesting sites for wildfowl Bird Conservation

A replicated, randomised and controlled paired study in tundra on Mitivik Island, Hudson Bay, Nunavut, Canada, in 2001 and 2003 (Fast et al. 2007), found that female common eider Somateria mollissima provided with shelters whilst nesting lost less weight over the incubation period, compared to control females without shelters (average weight at end of incubation of 1,312 g for 34 sheltered birds vs. 1,266 g for 31 controls). Sheltered birds, however, appeared to lose weight more rapidly at the end of incubation. Sheltered nests had more stable temperatures than controls (average temperature range was 6.1oC lower for sheltered nest). Paired nests were less than 10 m apart (to ensure similar microclimates) and were at similar stages of incubation when a shelter consisting of a 46 x 46 cm roof and two 25 x 46 cm walls (with 12, 2.5 cm holes in) was placed over one of the nests. The walls were positioned facing east-west.