Proximity to wind-power plants reduces the breeding success of the white-tailed eagle

As a clean and renewable energy source, wind power is expected to play a major role in climate change mitigation. Despite its benefits, the construction of large-scale wind farms in many parts of the world is a cause of concern for wildlife, including the often vulnerable raptor populations. Here, we examined the influence of distance to wind-power plants on the white-tailed eagle Haliaeetus albicilla in terms of (1) breeding success; (2) post-fledging survival; and (3) territory occupancy and turbine avoidance (via nest site changes). Our results show that the probability of a pair breeding successfully is lower when the territory is located closer to turbines, potentially because of collision mortality (to which adults are particularly vulnerable). A capture-mark-recapture analysis showed no evidence for the effect of distance on post-fledging survival, suggesting that collision risk may not have been greater for juveniles that fledged closer to a power plant. The levels of disturbance experienced by birds in the study areas were not great enough to prevent breeding at closer distances to the turbines. Our findings on breeding success underline the importance of building appropriately sited wind farms as a way to reduce or avoid undesirable effects on avian populations.