Meeting Abstract
Echolocating bats rarely forage in isolation and the presence of both conspecific and heterospecific individuals have the potential to produce acoustic interference. Recent studies have shown that at least one bat species, the Brazilian free-tailed bat (Tadarida brasiliensis), produces specialized social signals that disrupt the sonar of conspecific competitors. We discuss the differences between passive and active jamming signals and whether heterospecific jamming occurs in species overlapping spatiotemporally as well as whether such interference elicits a jamming avoidance response (JAR). We compare the capture rates of tethered moths and the echolocation parameters of big brown bats (Eptesicus fuscus) challenged with the playback of the jamming signal normally produced by Brazilian free-tailed bats and playback of modified versions of this signal. There were no differences in the capture rates of targets with and without the jamming signal though significant changes in both spectral and temporal features of the bats’ echolocation were observed. Flexibility in echolocation is an important characteristic for overcoming various forms of acoustic interference and may serve a purpose in interspecific interactions as well as intraspecific ones.
