Abstract
The global aspiration for clean energy needs to accommodate biodiversity concerns. While India’s wind energy has grown annually by ~ 15% in recent past, their ecological impacts have not been assessed systematically. We studied bird mortality at wind farms in Thar Desert; a renewable energy hotspot, harboring ~ 300 bird species including critically endangered vultures and bustards. Our study spanned 3000 km2 open natural ecosystem with ~ 900 turbines. We searched carcasses at 90 randomly selected turbines using seven multi-season surveys. We compared mortalities from the first survey to concurrent surveys at 28 control sites. We corrected mortality estimates for persistence and detection biases. We observed bird crossings at 16 turbines to examine relative vulnerability of species. We found 124 bird carcasses at turbines and none at control sites. Bias adjusted mortality was 1.24 ± 0.18SE bird turbine− 1 month− 1 which yielded annual mortality of ~ 4464 birds per 1000 km2 area. Mortality was lower in undulating grasslands, higher at single turbines than clustered turbines, and increased with hub height. Bird biometry or overlap between flight height and turbine impact zone did not influence relative vulnerability of bird families. To minimize these impacts, the transition from fossil fuels to renewable energy should mainstream regional assessments and mitigation measures.