Equipment for detecting animal ultrasound

Abstract The study of bioacoustics now includes many instances in which ultrasound is generated but can only be detected by the use of special equipment. In aerial encounters between bats and the insects that form their prey both participants use acoustical mechanisms which operate at 20–150 kc/s. More widespread observations of these phenomena are desirable and this article shows that the basic equipment is neither difficult nor expensive to acquire. Simple microphones and tuned detector/analysers are described, as well as the more elaborate techniques used for detailed analyses