Wind farms are shrinking golden eagles’ habitats as they are afraid of the blades, a study has found.
The birds of prey are eight times less likely to fly near turbines when they are rotating compared with when they are switched off, scientists from the ecological company Natural Research Projects have found.
It is thought the birds are avoiding areas where turbines are situated because the noise and movement makes them feel threatened. Another theory is that the circling blades remind them of human arms, or they associate them with human activity.
The findings run contrary to earlier research, which suggested that wind turbines primarily pose an injury threat to wildlife, as birds can get caught in the blades when they fly too close.
This is believed to be the first study to expose the threat to habitat posed by wind farms.
Dr Phil Whitfield, one of the study’s authors, said: "Previous research on Golden Eagles, notably in the United States, has tended towards collision with turbine blades as the main consequence of their interaction with wind farms.
"Our study shows across numerous wind farms in Scotland, this was not the case, but that deleterious habitat loss through avoidance of turbines was the main impact."
Scientists studied the behaviour of 59 golden eagles before and after the introduction of 80 wind farms in Scotland. GPS tracking devices recorded them at tens of thousands of locations and mapped their routes.
Computer modelling suggests they keep at least 70 metres away from the turbines when they are switched on and rotating.
It is hoped the findings could better inform plans by the Government to reintroduce golden eagles to the environment through "rewilding" – restoring an area of land to its natural, uncultivated state.
Environment Secretary George Eustice said earlier this year: "We want to see a nature-rich Britain with further action to bend the curve of species loss in this country. We will recover threatened species and provide opportunities for reintroduction through a range of projects."
The golden eagle was hunted to extinction in England and Wales during the 19th century.
Weighing up to a stone and with a wingspan of seven feet, it is now the top predator in the Scottish countryside, which is home to around 500 pairs. They mainly feast on rabbits and hares, and have an average lifespan of 23 years.
A "species reintroductions task force", run by Natural England, is examining how to bring back creatures lost due to human activities to reverse the decline of wildlife.
Speaking last year about the golden eagle reintroduction feasibility study, an RSPB spokesperson said: "The RSPB is broadly supportive of this idea.
"Seeing these magnificent birds back in England’s skies would be marvellous and restore a sense of wildness to some of our upland landscapes."
The study was published in the journal IBIS.