Britain's upland birds are in danger of being driven off hills and mountains by onshore wind farms. Scientists have found that birds, including buzzards, golden plovers, curlews and red grouse, are abandoning countryside around wind farms because the turbines act as giant scarecrows, frightening them away. The impact is small now because there are few wind farms but researchers warn that, with hundreds more planned, plus an increase in the size of turbines, the effect could become much worse. "We found evidence for localised reductions in bird breeding density around upland wind farms. Importantly, for the first time, we have quantified such effects across a wide range of species," said James Pearce-Higgins, an ecologist with the Royal Society for the Protection of Birds in Scotland. His research was conducted with scientists from Scottish Natural Heritage and the Scottish government's environment research directorate. It is one of the first scientific analyses of how the wind-farm construction programme might affect wildlife. The UK has 259 onshore wind farms, of which 108 are in England, 91 in Scotland, 33 in Wales and 27 in Northern Ireland. Planning permission has been granted for a further 222 and there are plans for another 270 after that. In the study Pearce-Higgins surveyed the populations of 12 bird species around a dozen upland wind farms in Scotland and northern England. These were compared with a similar number of control sites that had no turbines, but which had similar topography and vegetation. Upland areas were chosen because they have the strongest winds and so are preferred by wind-farm developers. They are also favoured, however, by some of Britain's most vulnerable bird species. Writing in the Journal of Applied Ecology, Pearce-Higgins and his colleagues said birds tended to stop nesting within half a mile of any turbine. Since the effect extends around each machine, up to two square miles could be affected by one turbine. Pearce-Higgins said: "Our results highlight significant avoidance of otherwise apparently suitable habitat close to turbines in at least seven of the 12 species studied, with equivocal evidence for avoidance in a further two species."