Dietary affinities, resource overlap and core structure in Atlantic Forest phyllostomid bat communities

Abstract

Abstract The Phyllostomidae is arguably the most diverse family‐level clade of mammals. Associated with this high diversity is considerable heterogeneity in resource utilisation among species and across locales of the Neotropics. Despite heterogeneity, few attempts have been made to synthesise dietary patterns even for smaller regions within the Neotropics. Atlantic Forest is a large dynamic ecoregion in the southern Neotropics that is distinct from other Tropical forests because of its extensive latitudinal extent, elevated climatic heterogeneity, biodiversity and long history of anthropogenic modification. I obtained data on dietary affinities of 34 species of bats from 35 different sites spanning the entire Atlantic Forest. In Atlantic Forest, as in other places in the Neotropics, phyllostomids consumed arthropods, vertebrates, fruits, nectar and blood. Frugivores consumed and dispersed the fruits of 99 different species of plants and nectarivores pollinated an additional nine others. Dietary overlap was modest, yet significantly greater than expected based on a null model. The main axis of variation in diet separated species that primarily consumed animal material from those that primarily consumed plant material and this axis was significantly related to phylogenetic affinities of species. Unlike in other places in the Neotropics, frugivorous bats did not exhibit a core structure related to genus‐to‐genus matching of bat genera with plant genera. Generality of diets of frugivorous bats, further indicated by non‐randomly high dietary overlap, is likely to degrade core structure in these primarily Subtropical communities. Co‐occurrence of a large number of generalist bat species, seasonal climates and ubiquitous anthropogenic modification may serve to promote generality of resource utilisation of bats in Atlantic Forest. The Neotropics is vast and the bats that live within it are diverse. Future studies should explore spatial dynamics of dietary affinities and resource overlap to increase understanding of the context of strong and weak core structure of phyllostomid bat communities.