Birds and bats suffer higher mortality from wind turbines during seasonal migrations, a fact explored in a study published in PLoS ONE. The research analyzes data gathered from 248 wind turbines across the United States, a substantial portion of the nation’s installations, with the aim of uncovering patterns in wildlife fatalities linked to turbine operations.
Researchers, led by John Lloyd and colleagues, tallied carcasses of birds and bats found within turbine sites over the period from 2009 to 2021. The dataset revealed that, when only records with clearly known dates were included, 3,789 birds and 10,291 bats were recovered. The study emphasizes that these figures likely underrepresent total mortality due to imperfect detection and limited reporting in some areas.
The resulting models indicate that seasonal mortality patterns differ by ecoregion. In the central and western United States, where turbines are densely clustered in the prairie and plain landscapes, many bird species inhabit the region year-round and face a relatively constant risk of collision with turbine blades. By contrast, forest-dwelling birds experience mortality linked to long-distance migrations, showing two distinct death peaks aligned with spring and autumn migrations. Across all regions, bat fatalities peak in late summer and fall, with a notable rise from mid-June through mid-November, regardless of local habitat type.
The authors propose that understanding these patterns can inform the strategic placement and operation of wind energy facilities to minimize harm to wildlife while maintaining the benefits of clean energy. Their findings suggest that targeted siting, timing of activities, and wildlife monitoring can help reduce avian and chiropteran fatalities during migration periods.
Overall, the study contributes to a growing body of work aiming to balance renewable energy development with wildlife conservation in North America, offering data-driven insights for policymakers, operators, and researchers. [Citation: PLoS ONE study on wind turbines and wildlife fatalities]