Aerial hawking in a gleaning specialist bat (Trachops cirrhosus) does not involve a high-resolution buzz

Aerial-hawking bats adjust their biosonar in the search, approach and capture phases of echolocation to guide aerial prey interception. Some bat species have secondarily evolved a gleaning strategy that relies on passive acoustic cues to detect and capture prey on vegetation. Here, we tested the hypothesis that such a gleaning specialist, the fringe-lipped bat, Trachops cirrhosus, must use stereotyped aerial-hunting echolocation phases, including a buzz when opportunistically capturing aerial prey. Using data from sound-recording tags on 8 individuals, we reject this hypothesis by showing that fringe-lipped bats can detect and intercept aerial prey by echolocation but do so with modest biosonar adjustments and without producing a high-resolution buzz. These findings challenge the notion that the stereotyped echolocation phases of hawking bats are required for aerial prey capture and show that echolocation is an extremely versatile sensory system that can be employed across otherwise specialized foraging niches.