The frog-eating bat (Trachops cirrhosus) uses frog mating calls to detect, locate, and assess its prey. Like the female túngara frogs, this bat shows a strong preference for complex calls over simple ones (Ryan et al., 1982).
T. cirrhosus ranges from southern Mexico to Brazil (Cramer et al., 2001) and is highly opportunistic in its diet, consuming a large variety of arthropods (Bonaccorso, 1978; Kalko et al., 1996; Bonato et al., 2004), as well as many types of vertebrate prey, including lizards, birds, smaller species of bats, and most famously, frogs (Bonato & Facure, 2000; Rodrigues et al., 2004). T. cir- rhosus is not alone in feeding on frogs; several species of bats are frog predators. What is extraordinary about T. cirrhosus is its ability to eavesdrop on the sexual advertisement calls of male frogs and use these calls to obtain its prey.
Studies from Barro Colorado Island and the surrounding areas in Panama show that T. cirrhosus responds to the calls of numerous frog species. Given the frog mating call alone, T. cirrhosus can distinguish palatable from poison- ous prey, and prey that is too large to capture from prey that is an appropriate size (Tuttle & Ryan, 1981). It prefers higher-amplitude túngara frog calls to ower-amplitude calls, and it prefers calls at a faster call rates to calls at slower call rates (Tuttle & Ryan, 1981). It also generalizes from the calls of known prey to the calls of unknown prey (Ryan & Tuttle, 1983). While T. cirrhosus rely primarily on frog advertisement calls in its hunting approaches, experi- ments show that at close range bats can also use echolocation and chemical cues to sequentially update their assessment of prey quality (Page et al., 2012).