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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. [ABSTRACT FROM AUTHOR]

More than half of Brazil's Cerrado has been converted to agricultural land use, threatening its rich biodiversity that includes > 200 anuran species, most of which have aquatic larvae and are thus doubly susceptible to the environmental impacts of agriculture. Past research has largely focused on how land-use change affects adult anurans, which ignores potential impacts on the critical larval stage. We therefore investigated how agricultural land use (250–1000 m scale) and the local pond environment affect the diversity and distribution of tadpole assemblages across the central Cerrado. Tadpole richness declined significantly with increasing cropland within 250 m of ponds and with increasing water pH in permanent ponds. Permanent ponds are more prevalent in agricultural areas where streams are impounded to provide water for irrigation and livestock, and water pH increases with increasing agriculture, likely due to the widespread use of agricultural lime in the Cerrado. Tadpole communities exhibited high beta diversity (81–86% dissimilarity), with species replacement rather than nestedness accounting for 90–97% of species differences between ponds, which was largely driven by hydroperiod. Six species accounted for 70% of the dissimilarity, with most species either more abundant or found only in temporary ponds. Increased lentification, a corollary of agricultural land use, is profoundly altering tadpole assemblages, which has consequences for overall anuran diversity in the Cerrado given that permanent ponds support a different and less-diverse larval assemblage than ephemeral wetlands. Anuran conservation in the Cerrado should therefore additionally consider maintaining or restoring wetland hydrology and native-vegetation buffers around wetlands. [ABSTRACT FROM AUTHOR]

Context: Environmental filtering and limiting similarity have both been hypothesized to influence patterns of species co-occurrence, but in contrasting ways. While environmental filtering results in a greater similarity of functional traits among co-occurring species, limiting similarity predicts that only species with different functional traits can co-occur. Objectives: We evaluated the roles of environmental filtering versus competition in shaping patterns of species co-occurrence in terrestrial versus arboreal species of pond-breeding anurans, and also the influence of local and landscape environmental factors on those patterns, in the Brazilian Cerrado. Methods: We surveyed anurans within 85 ponds and adopted trait-based approaches to investigate patterns of co-occurrence within terrestrial and arboreal species groups. Results: Local-scale environmental filters related to hydroperiod were more important than landscape factors. Habitat split was an important landscape filter, as was the amount of forest relative to pasture cover for arboreal species and the number of water bodies for terrestrial species. Habitat filtering was trait-mediated for arboreal species within ponds of similar size, hydroperiod, and degree of habitat split. Competition was weaker than environmental filters and led to a checkerboard distribution in arboreal species, whereas terrestrial species exhibited limiting similarity within small ponds. Conclusions: The processes that shape species co-occurrence patterns are dependent on spatial scale, degree of habitat degradation, and relative habitat use of species (terrestrial vs. arboreal), such that environmental changes as a result of land-use intensification have the potential to profoundly alter the structure and dynamics of pond-breeding anuran communities in the Cerrado. [ABSTRACT FROM AUTHOR]