Bats (Mammalia: Chiroptera) of Ubajara National Park, Ceará, Brazil: a diversity assessment using complementary sampling methods

Abstract

Bats are unique among mammals in their capacity for powered flight and present high species diversity and feeding habits in the Neotropical region. Despite the remarkable increase in knowledge on the distribution of neotropical bats in recent decades, information on the species’ occurrence throughout Brazil is still widely heterogeneous, with significant knowledge gaps in many biomes. The Ubajara National Park (PNU), northwestern Ceará, is an area of extreme biodiversity in the Caatinga biome, characterized by several natural caves associated with a noticeable bat community. Herein, we carried out a complementary inventory of bat diversity in the PNU, focusing on six caves and their surrounding foraging sites. Two surveys totaling 36 sampling nights were conducted using complementary methods such as mist nets, harp trap, roosting searches, and acoustic monitoring. Thirty species of bats belonging to eight families were recorded. We found significant complementarity between the sampling methods resulting in the stabilization of the rarefaction curve. Eight species were found in roosting colonies in at least one of the sampled cavities. A total of 965 individuals from 18 species, with the majority belonging to the family Phyllostomidae, were recorded using active sampling techniques. Passive acoustic monitoring yielded 14 different sonotypes of species from the Emballonuridae, Mormoopidae, Molossidae, Vespertilionidae, and Noctilionidae families. The acoustic activity of bats from distinct families was higher in the dry season and varied throughout the night. Two species registered with passive acoustic monitoring were among the captured ones, thus reinforcing the importance of diversifying methodologies to obtain more complete bat inventories.