No abstract

Across the globe, millions of hectares of native vegetation have been replaced by commercial plantations, with negative consequences for biodiversity. The effects of the replacement of native vegetation with commercial plantations on the functional and phylogenetic diversity of bat assemblages remain understudied, and most studies have focused exclusively on the taxonomic component of diversity. Here, we investigate how the replacement of natural savannahs by acacia plantations affects the α- and β-diversity of bat assemblages. We sampled bats, using mist-nets at ground level, in natural forest, savannah areas and acacia plantations, in the Lavrados de Roraima in the northern Brazilian Amazon. Our results show that, in general, acacia is less diverse than native forests in terms of taxonomic and functional diversity, and is also less taxonomically diverse than the savannah matrix which it substitutes. The observed patterns of α- and β-diversity found in the present study are in large part driven by the superabundance of one generalist and opportunistic species, Carollia perspicillata, in the acacia plantations. Taken together, our results show that the replacement of areas of natural savannah by acacia plantations causes a regional loss in diversity across all diversity dimensions: taxonomic, functional and phylogenetic. However, further studies are required to fully understand the ecological and conservation implications of this landscape change.

Large islands near the mainland tend to have greater species richness than smaller or remote oceanic islands. This study aimed to compare the community of Phyllostomidae bats on the island of Maracá-Jipioca, in Amapá, northern Brazil, and on the adjacent mainland. We also compared the community in four vegetation types present in both areas. Sampling occurred during the wet and dry seasons of 2010 at 24 independent sampling points. We recorded 333 Phyllostomidae bats belonging to 19 species. Species richness did not differ between the island and mainland but was different among the vegetation types, with grassland being the poorest. Species composition and abundance were different between the island and mainland. This difference was significant for Carollia perspicillata and Phyllostomus elongatus, which were more abundant on the island and mainland, respectively. Artibeus concolor did not exhibit differences between the two areas but differed among the vegetation types, being more abundant in flooded forest. Our findings did reveal that isolation and distance act as selective pressures for Phyllostomidae bats.