Adverse effects of noise pollution on foraging and drinking behaviour of insectivorous desert bats.

Human-generated noise can deleteriously affect many animals. Echolocating bats, which crucially depend on sound for their activity, might therefore serve as bioindicators to quantify the ecological effects of sound pollution. While the influence of sound pollution on animal behaviour has been widely studied, the impact of music is almost unknown. We tested whether music, broadcast loudly, affects bats' foraging and drinking behaviour. The study was done at two waterbodies, where bats drink and forage in the Negev Desert, Israel, during summertime, when water availability is limited: both sites, one isolated natural pond and one artificial waterbody, frequently host recreational parties and concerts. We broadcast music whose frequency range did not overlap with that of bat echolocation calls, and acoustically assessed bat activity before and after the music broadcast. At the remote waterbody, used by bats as a drinking site, the number of bat passes did not vary between treatments. However, after music was broadcast, bats performed significantly more unsuccessful drinking attempts. At the artificial waterbody—a foraging site—activity decreased significantly after music was broadcast. Additionally, music had a cumulative effect on bats, since overall activity significantly decreased over the experimental period. Noise may affect bats by narrowing their attention or distracting them from their primary task. Broadcasting loud music near remote waterbodies is, therefore, significantly hazardous for bats and other wildlife. [ABSTRACT FROM AUTHOR]