Ultraviolet Illumination as a Means of Reducing Bat Activity at Wind Turbines

Tree-roosting bats die often at the blades of wind turbines, but reasons for this higher susceptibility of ‘tree bats’ remain unknown. One possibility is that bats might not be able to discriminate wind turbines from... [ view full abstract ]

Tree-roosting bats die often at the blades of wind turbines, but reasons for this higher susceptibility of ‘tree bats’ remain unknown. One possibility is that bats might not be able to discriminate wind turbines from trees. Attraction from afar may be a chronic problem of bat fatalities at wind turbines, because distant attraction could act against or beyond the influence of many curtailment and deterrence strategies. Despite low visual acuity, bats navigate by vision and can see the silhouettes of trees from great distances in darkness, a plausible distant-attraction cue. Furthermore, bats see light in the ultraviolet (UV) spectrum. We integrated these concepts and are pursuing the possibility that dim UV light that is not visible to humans or birds can be used to visually enhance turbines so that bats perceive them differently from long distances. Decreasing visual resemblance between turbines and trees at night might keep bats from approaching and perishing at turbine blades. This talk will detail our ongoing, multi-year effort to assess the practicality of using dim UV light to keep tree bats from turbines. Our promising results thus far have us moving forward with this research and we are now planning a full efficacy trial on operating wind turbines.