Diet and trophic structure in assemblages of montane frugivorous phyllostomid bats

Abstract

Neotropical frugivorous bats display a trophic structure composed of bat species with dietary preferences of core plant taxa (Artibeus-Ficus + Cecropia, Carollia-Piper, Sturnira- Solanum + Piper). This structure is hypothesized to be an ancestral trait, suggesting that similar diets would be observed throughout a species' range. However, most evidence comes from lowlands where data from montane habitats are scarce. In high mountain environments both diversity of bats and plants decreases with altitude; such decline in plant diversity produces less plants to feed from, which should ultimately affect the trophic structure of frugivorous bats in mountain environments. Here, we present a comprehensive review of the diet of frugivorous bats in Neotropical montane environments and evaluate their trophic structure in middle and higher elevations by combining a literature database with field data. We use the concept of modularity to test whether frugivorous montane bats have dietary preferences on core plant taxa. Our database revealed 47 species of montane bats feeding on 211 plant species. We find that the networks are modular, reflecting the trophic structure previously reported. We also found that in highlands the tribe Ectophyllini are Cecropia + Cavendishia-specialists rather than Ficus-specialists, and we describe new interactions reflecting 14 species of plants, including three botanical families previously not reported to be consumed by bats.