Differential responses to visual and acoustic cues during escape in the bat Anoura geoffroyi: Cue preferences and behaviour

Abstract

Wild Anoura geoffroyi tested in their home cave can use either visual or acoustic cues to guide their escape from a Y-maze; but they selectively attend to the visual cue whenever possible. When orienting visually, bats choose to ‘head for the light’ which in a cave marks the exit. When forced to orient acoustically, bats select a closed runway and hang up to roost. With each of the six combinations of visual and acoustic cues tested, bats emit echolocation cries in most trials and indicate by their behaviour that they are aware of the acoustic parameters of their surroundings. Nonetheless, they select their escape route visually whenever possible, disregarding seemingly pertinent acoustic information. This persistent attention to the visual cue was even more marked when captive bats were tested in the laboratory. The results distinguish the functions of vision and echolocation and show the complex relationship between these two senses in microchiropteran bats.