Streetlights and bat conservation

Day, J., Baker, J., Schofield, H., Mathews, F. & Gaston, K.J. (2015) Part-night lighting: implications for bat conservation. Animal Conservation, DOI: 10.1111/acv.12200.

Artificial nighttime lighting has many effects on biodiversity. A proposed environmental managementoption, primarily to save energy, is to alter the duration of night lighting. Using the greater horseshoe bat Rhinolophus ferrumequinum as an example of a photophobic species, we explored roadside behaviour patterns throughout the night to assess the potential impact of part-night lighting. We found a large primary peak in activity 1 h after sunset, followed by a smaller secondary peak before sunrise. Simulated part-night lighting scenarios reveal that to capture a large proportion of bat activity, streetlights should be switched off before midnight. Current proposed uses of part-night lighting are unlikely to capture natural peaks in activity for nocturnal species.