Reactions of waterfowl (Anatidae) to the sounds of UAVs

Abstract

Geese, swans and ducks (Anatidae) are thought to avoid the sound of UAV rotor blades. In this study we measured the reactions of flocks of Anatidae to prerecorded UAV rotor sounds. The sound levels heard by Anatidae flocks were estimated using distance attenuation models of UAV rotor sounds. Our results indicated that rotor sounds below about 50 dB were not a primary avoidance factor, whereas avoidance behavior was triggered mainly by the visual impact of the UAV. However, if rotor sounds are louder than 50 dB, they may trigger avoidance by Anatidae.