Bats in fragments of xeric woodland caatinga in Brazilian semiarid

Caatinga is a mosaic of xeric woodland with several savanna and tropical rainforest enclaves in interior of Northeastern Brazil. These enclaves seemingly result from expansion/retraction of mesic and dry biomes of South America following dynamics of climate changes in Pleistocene. Little is known about the influences of proximity to enclaves in species composition of xeric woodlands. The objective of this study was to analyze faunal components of bat communities in xeric woodland caatinga of the middle São Francisco River plain. Bats were collected in 20 caatinga fragments during one year. These data were compared with bibliographic data about bats' surveys in caatinga. The results showed high species richness in study area. We found a strong influence of rainforests but almost no influence of savanna habitats on bat species composition. There were no differences between habitats, however, when we considered taxonomy, body size and the composition of feeding guilds. Species richness and habitat use patterns may be associated with both the past occurrence of rainforests in the region during the Holocene as well as proximity to current rainforest enclaves.

► We evaluated the bat fauna composition caatingas of Middle São Francisco River Plain. ► The caatingas of Middle São Francisco River Plain have a high species richness of bats. ► The bat fauna have a strong influence of Rainforest and Xeric components. ► The bat fauna have no species shared only with Savannas components.