Wind energy turbines kill hundreds of thousands of bats annually globally, creating a significant and growing wildlife welfare and conservation challenge.
Wind energy has critical climate benefits but imposes real welfare and conservation costs on bat populations. Bats struck by turbines or killed by barotrauma die from traumatic injury, internal hemorrhage, and collapsed lungs. Deaths often occur during autumn migration when bats travel in concentrated paths that overlap with wind farm siting. Curtailment programs that halt turbines during low-wind migration nights are the most cost-effective mitigation, imposing only 1-3% energy production loss for 50-90% mortality reduction. Acoustic deterrent systems are also being developed. Mitigation should be standard practice at all wind facilities in bat migration zones.