Evidence of bats colliding with wind turbines has been available from the US and Europe since the early 2000s and there is now evidence of this from the UK.
Direct impacts of wind farms can include collision and barotrauma (damage to tissues from air pressure changes around turbines); indirect impacts can include habitat loss (roosts, commuting routes and foraging areas) and fragmentation.
The Bat Conservation Trust supports the development of sustainable energy, including wind, but in line with Eurobats resolutions stresses that it is imperative that the potentially harmful impacts on bats and other wildlife (both direct and indirect) are taken into account through ecological impact assessments, carried out by professional ecologists, for all wind projects.
Ecological impact assessments should be carried out before deciding on the siting of onshore and offshore wind turbines and wind farms, large and small.
Where impacts are predicted, avoidance/mitigation measures and monitoring should be secured through robust planning conditions. Mitigation measures (in the form of curtailment of wind turbines during periods of high bat activity) are now known to be successful in reducing the impacts of wind turbines on bats whilst minimising losses in power generation. These methods are constantly being refined but ongoing monitoring is essential to inform the approach.
We would also like to see monitoring of existing wind turbine sites and remedial action where any issues are identified.
The Bat Conservation Trust was part of a collaboration of organisations involved in research into the impacts of wind farms on bats in the UK (Understanding the Risk to European Protected Species (bats) at Onshore Wind Turbine Sites to inform Risk Management) and subsequently producing the guidance on bats and wind farms, including surveying, impact assessment, mitigation and monitoring measures (Bats and Onshore Wind Turbines: Survey, Assessment and Mitigation).
We also recently submitted a response to the Offshore Energy Strategic Environmental Assessment (OESEA) Report 4 Consultation.
The Bat Conservation Trust also contributes to the work of the Eurobats Intersessional Working Group on Wind Turbines and Bat Populations.
Other useful references