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Providing evidence to improve practice

Individual study: Reducing egg predation to increase the productivity of capercaillie Tetrao urogallus in Abernethy Forest, Inverness-shire, Scotland

Published source details

Summer R.W., Green R.E., Proctor R., Dugan D., Lambie D., Moncrieff R., Moss R. & Baines D. (2004) An experimental study of the effects of predation on the breeding productivity of capercaillie and black grouse. Journal of Applied Ecology, 41, 513-525

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

Control predators not on islands for gamebirds Bird Conservation

A controlled before-and-after study years in northern Scotland between 1989 and 1999 (Summers et al. 2004) found that the breeding productivity of western capercaillie Tetrao urogallus and ‘survival’ rates of 48 artificial nests were higher during the last three years (1994-6) of predator removal, compared to nine sites without predator removal. However, in the previous two years of predator removal (1992-3) and years without removal (1989-91, 1997-9), productivity was lower on the experimental site. In non-removal years, productivity averaged 0.1 chicks/female, compared with 1.4 chicks/female in removal years. Predator removal involved trapping carrion crows Corvus corone (a total of 368) and shooting red foxes Vulpes vulpes (a total of 22 adults and 52 cubs).