Abstract
There is increasing concern about the impact of the current boom in wind energy facilities (WEF) and associated infrastructure on wildlife. However, the direct and indirect effects of these facilities on the mortality, occurrence and behaviour of rare and threatened species are poorly understood. We conducted a literature review to examine the potential impacts of WEF on grouse species. We studied whether grouse (1) collide with wind turbines, (2) show behavioural responses in relation to wind turbine developments, and (3) if there are documented effects of WEF on their population sizes or dynamics. Our review is based on 35 sources, including peer-reviewed articles as well as grey literature. Effects of wind turbine facilities on grouse have been studied for eight species. Five grouse species have been found to collide with wind turbines, in particular with the towers. Fifteen studies reported behavioural responses in relation to wind turbine facilities in grouse (seven species), including spatial avoidance, displacement of lekking or nesting sites, or the time invested in breeding vs. non-breeding behaviour. Grouse were affected at up to distances of 500 m by WEF infrastructure, with indications of effects also at bigger distances. In six cases, a local reduction in grouse abundance was reported in areas with wind turbines, which possibly affected population size. Due to the differences in study duration and design, we cannot provide general conclusions on the effects of WEF on grouse populations. We advise applying the precautionary principle by keeping grouse habitats free of wind energy developments, in particular where populations are small or locally threatened. Future studies should preferably apply a long-term before-after-control-impact design for multiple areas to allow for more general conclusions to be drawn on the effects of WEF on rare and threatened wildlife species.