Animal smorgasbord: the highly diverse diet of the Woolly False Vampire Bat ( <i>Chrotopterus auritus</i> ) in southeastern Mexico

Abstract Knowledge of multiple roosts of the carnivorous bat Chrotopterus auritus (Phyllostomidae) on the Yucatan Peninsula, Mexico, allowed for the first multi-seasonal multi-roost study of its ecology in a seasonal location near the northern limit of its distribution. Discarded prey remains were gathered systematically from 3 roosts, from January 2019 to March 2020 and from July to November 2021, with additional samples from 2018 and some material gathered opportunistically from another 3 roosts. Prey fragments were classified morphologically and identified through direct comparisons with museum specimens, ID guides, expert advice, and online photographs of species present in the area. Ecological data about the identified prey were compiled from the literature to search for insights into how, when, and where C. auritus is hunting. A total of 4,427 individual fragments of prey found beneath roosts yielded a minimum total of 962 individual prey and 115 taxa including 77 vertebrates, 33 arthropods, and 5 plants (fruit). Species-level identification was possible for 88 taxa and genera level for 10. The diet of C. auritus in this region is estimated to total up to 159 ± 14 prey species and was composed mainly of terrestrial vertebrates, especially rodents. Together, terrestrial vertebrates contribute 64% of individual prey and almost 97% of the total estimated mass consumed. Variation was observed in the diet throughout the year, and some differences were found between the 3 roosts studied systematically, potentially related to differences in the preservation of remains within the different structures due to scavenger access; in the availability of prey; and in the habits of bats in different roosts. Chrotopterus auritus appears to be an opportunistic and plastic predator, capable of feeding on a wide variety of organisms.