Supplementary material from "Recognition of predator cues hinders social communication"

Antipredator defenses often rely on perception and discrimination of cues from predators, and alteration of behavior by potential prey. Characteristics of acoustic signals allow eavesdropping on calls of predators, permitting listeners to gauge predation risk by assessing the location and identity of the signaler. We tested the ability of bats that are preyed upon by other bats to discriminate between echolocation calls of predators and non-predators, and the impact of risk reduction strategies on communication. Bats distinguished between echolocation calls of predators and non-predators, recognizing predator calls with high accuracy. However, bats were more cautious when the structure of non-predator calls was similar to predator calls. In the presence of predator calls, bats ceased social communication, which could impact sociality and disrupt group cohesion.