Morcegos (Mammalia, Chiroptera) em refúgios diurnos artificiais na região Sudeste do Brasil

Abstract

Urbanized environments presents several constructs that can be used as roosts for bats. Roosts are fundamental to the development of the bats and social interactions that occur between members of the colony, besides being used as shelter from predators and to rest. The present work has as main objective to study bats using buildings in southeastern Brazil, emphasizing the state of Rio de Janeiro. In the first chapter, a literature review was conducted, in order to update the records of species that utilize buildings during the day in the state of Rio de Janeiro, to list such occurrences in southeastern Brazil and to determine which species coexist. The occurrence of 37 species using buildings in the region was identified, where 24 of them cohabit. Moreover, this study allowed the identification of the states of Espírito Santo and Rio de Janeiro as those with the lowest and highest number of samples in artificial shelters for bats, respectively. The second chapter had as main objective the study of the bats species Molossus molossus using residences in Marambaia Island, Rio de Janeiro, Brazil as roost, and analyze some abiotic features of these buildings. A total of 28 households were studied between March 2012 and February 2013, with the completion of one to three samples in each of the residences. To catch the bats, mist nets and trap were used, on different days, in order to compare the efficiency of two methods. Factors such as size, luminosity, number of entries and internal temperature of the roofs of the residences used as roosts were checked, in order toidentify the existence of a pattern in roosts with the largest number of individuals of the studied species. Displacement of individuals between roosts and time of the captures were analyzed. There was no relationship between the number of displacements and the density of individuals on the roost, as well as no pattern on the characteristics of the houses occupied by larger or smaller number of individuals of the species. Therefore, other factors must be analyzed so that the causes of occupations and displacements could be identified, as the humidity and the amount of guano within the roosts. In rooftops with large number of entrances, mist nets are more effective in capturing M. molossus. In rooftops with few entrances, the trap is efficient and presents advantages as the lowest cost and durability. Molossus molossus sheltering in the studied buildings of the Marambaia Island possibly form a single colony, and use one of the roosts to reproduce. The species showed peak of activity at twilight and no difference in activity time in relation to the moon phases. The ongoing study in buildings used by bats as roosts is important for acquiring more knowledge of these sites, and about the biology of these animals, which allows proper management of bats in anthropogenic environments