Echolocation and flight behaviour in hearing-impaired and normal-hearing bats

Bats are acoustic specialists. Not only do they orient and forage with their ears, but they also communicate with each other using a rich repertoire of complex calls. Unlike most mammals, where the vocal repertoire is innate, bats have been considered vocal learners. Vocal learning refers to an animal’s ability to acquire new vocalizations through imitation. Known best for this trait are of course humans and birds, and the only other known examples are marine mammals and elephants, both hard to study. So, bats are the ideal model species. An animal learning a new vocalization must be able to hear and imitate new sounds, and then improve this imitation using auditory feedback. Deafening experiments are therefore critical to verify vocal learning. In this talk we will have a look at the vocalization and flight behavior of both normal-hearing bats and bats that were acoustically deafened at birth. Pups of both groups thrived and grew into adults that are socially integrated in the colony and eager flyers. Together, these bats give us some surprising insights on what they may or may not hear and how it affects the way they move through their environment.