Singing away from home: Songs are used on foraging territories in the African megadermatid bat, Cardioderma cor

The diversity of song repertoires and functions of singing in mammals have been little investigated. In bats, singing in the roost to court and defend mates has been studied; however the concept of territorial behaviors and the role of singing outside of the roost are poorly understood. The heart-nosed bat, Cardioderma cor, roosts in groups in the hollows of baobab trees, but disperses to exclusive areas whereby they move about foraging and singing. We investigated singing in this species by mist-netting, pit-tagging, and tracking 12 singing individuals during which we recorded songs and collected movement and singing behavioral data. Male C. cor individuals returned to same foraging area nightly, which are often over 100 m across, and favored perches whereby they sang back and forth with neighbors. Compared to high frequency echolocation, low-frequency, repetitive song syllables are likely adapted for song transmission across the cluttered bush habitat. Songs varied within and across individuals acoustically and temporally. Song playbacks elicited investigative and aggressive responses, confirming that these bats use song to create and defend territories. Song variability supports the possibility of other functions of singing, such as discrimination of conspecifics or displays of motivational level.