Estrutura das comunidades de morcegos em fragmentos de Cerrado e Floresta Estacional Semidecidual na região de Pirassununga/SP

Abstract

Bats are important elements of the Cerrado and Atlantic Forest biomes, considered priority hotspots for conservation. Due to their great diversity and morphological adaptations, they are pollinators, seed dispersers and pest controllers. They constitute about a quarter of the mammalian fauna of the tropics, with 181 species for Brazil and 81 for the state of São Paulo, whose vegetation has undergone processes of great exploitation. In this scenario, interspecific competition is described as a determining factor in the community structure of bats that is shaped by time, space and feeding factors. To understand the relationship between species and ecosystems, studies are needed to identify and analyze how communities are structured in the environment. For the region of Pirassununga/SP, Brazil, there is only the study by Silva (2017) on the survey of bat species. Thus, the objective of this study was to conduct a survey of bat species existing in the Cerrado and Semideciduous Seasonal Forest fragments of FAYS Farm, in the municipality of Pirassununga, checking the species richness, diversity and similarity, in addition to verifying how the bat community is structured in these two biomes. The study site belongs to the Air Force Garrison, with 1173 ha of Seasonal Semideciduous Forest and 827 ha of Cerrado. Six mist nets were used to capture the individuals four times per month, each lasting four hours, for nine months. Identification of the captured species was made with the aid of keys and identification guides, and after the necessary information was recorded the animals were released at the same location, with the exception of one specimen of each species that was placed in Museu de Zoologia da USP in São Paulo, Brazil. The feces were analyzed in the laboratory to identify the items consumed in the diet of the bat species. With a sampling effort of 1522 m²/h, 222 individuals of 18 species were captured, 16 of which occurred in the Semideciduous Seasonal Forest and 13 in the Cerrado. The most abundant species were Carollia perspicillata, Artibeus lituratus and Desmodus rotundus, with no significant difference in capturability between the areas. The Phyllostomidae family was the most captured, due to the mist net method in the understory. For the Semideciduous Seasonal Forest area, the species richness indices showed that there are still more species to be sampled, a common result in tropical environments. The communities of the two biomes are similar in terms of species composition, with the Semideciduous Seasonal Forest being slightly more diverse, due to the greater availability of resources. The number of captures showed no significant relationship with mean temperature or mean relative humidity, but night flights seem to be affecting the capturability. Females were captured in larger proportion than males, and the breeding period seems to follow the availability of resources, which fluctuates according to the months and environments. The frugivores of the Phyllostomidae family were the most captured, and 17 plant species were identified, in addition to insects and pollen as items belonging to the diet of all species collected. All of them tended to start their activities soon after sunset, with differences between species according to the food item consumed and the need to avoid competition for these items. The species found are characteristic of environments with a certain degree of human disturbance, and the results showed the importance of the species as pollinators, pest controllers, and dispersers, especially of pioneer plants. In addition, they revealed the presence of more species to be sampled, indicating the need for continued studies in this area.