The Abundance and Diversity of Phyllostomid Bats are Influenced by Environmental Factors, Landscape Composition, and Configuration in Oaxaca, Mexico

Abstract

Human-induced changes in landscape composition and configuration have a significant impact on species, including bats. Some bat species may be affected, while others can take advantage of the new available resources. In this study, we analyzed the response of the abundance, effective number of species, and dominance of bats to landscape composition and configuration, as well as a set of environmental factors in the municipalities of Santa María Huatulco and San Miguel Lachiguiri, Oaxaca, southeastern Mexico. We used a multimodel inference statistical approach to identify those variables explaining bat abundance and diversity of bats captured with mist nets. A 5.5 km radius circular landscape was established from an urban center in Huatulco and Lachiguiri. Within these areas, 1 km radius units (nine in Huatulco and eight in Lachiguiri) varying in the proportion of tropical forest, urban area, agriculture, and grassland were established. From 2020 to 2022, we captured 477 bats (58.49% in Huatulco and 41.51% in Lachiguiri) belonging to 21 species. The most abundant species were Artibeus lituratus (33.1% of the captures) and Artibeus jamaicensis (21.4%). The diversity of trophic guilds was twice as high in Lachiguiri (n = 6) compared to Huatulco (n = 3). In general, the variables that influenced the abundance and diversity of bats were the proportion of the landscape covered by human settlements and by deciduous forest, the fractal dimension index, temperature, seasonality, and distance to urban centers. Our results show that changes in landscapes, as well as temperature, play an important role in bat diversity in the study area. Conservation actions should be aimed at conserving all elements of the landscape that allow increasing the availability of resources (i.e., food, roosts) and, with it, the diversity and abundance of neotropical bats.