Hearing in American leaf-nosed bats. IV: the Common vampire bat, Desmodus rotundus.

We behaviorally determined the audiograms of three Common vampire bats (Phyllostomidae, Desmodus rotundus), a species specialized to exist exclusively on blood. The bats were trained to respond to pure tones in a conditioned suppression/avoidance procedure for a blood reward and a mild punisher for failures to detect the tones. Common vampire bats have a hearing range from 716 Hz to 113 kHz at a level of 60 dB. Their best hearing is at 20 kHz where they are slightly more sensitive than other bats, and they have a second peak of good sensitivity at 71 kHz. They have unusually good sensitivity to low frequencies compared to other bats, but are less sensitive to low frequencies than most mammals. Selective pressures affecting high-frequency hearing in bats and mammals in general are discussed.