Spatiotemporal patterning of acoustic gaze in echolocating bats navigating gaps in clutter

Abstract

Summary We challenged four big brown bats to maneuver through abrupt turns in narrow corridors surrounded by dense acoustic clutter. We quantified bats' performance, sonar beam focus, and sensory acquisition rate. Performance was excellent in straight corridors, with sonar beam aim deviating less than 5° from the corridor midline. Bats anticipated an upcoming abrupt turn to the right or left by slowing flight speed and shifting beam aim to “look” proactively into one side of the corridor to identify the new flightpath. All bats mastered the right turn, but two bats consistently failed the left turn. Bats increased their sensory acquisition rate when confronting abrupt turns in both successful and failed flights. Limitations on biosonar performance reflected failures to switch beam aim and to modify a learned spatial map, rather than failures to update acquisition rate.

By a whisker: the sensory role of vibrissae in hovering flight in nectarivorous bats

“…BRNs are consistent ways in which individuals differ from each other while engaged in the same behavioural tasks and are an important and useful way to quantify aspects of animal personality. BRNs have now been documented in bats both in a sensory context [35,36] and in a behavioural foraging context [37], and they promise to be an important aspect in future research of bat behavioural ecology. Although it is possible that these differences arise from slight differences in vibrissa trimming procedures, we think that it is unlikely because we consistently trimmed vibrissae to the length of the surrounding fur and checked that no visible vibrissa tips were left protruding from the chin and sides.…”