Sleeping site selection by black lion tamarins: a comparison between continuous forest and fragment

Sleeping site selection by primates can be influenced by several factors, such as predation, thermoregulation and territorial defense. Our objective was to investigate which of these factors influence the sleeping site selection by black lion tamarins and if there is divergence in the characteristics of the sleeping sites between a continuous forest and a fragment. We studied two groups of black lion tamarins, one in a continuous forest and one in a small and isolated fragment in the Pontal do Paranapanema, São Paulo, Brazil. We collected data on the physical characteristics of the sleeping sites and available trees within the both habitats. We used Mann-Whitney tests to compare the physical characteristics of the sleeping sites with available trees and Resource Selection Functions (RSF) to understand which of these characteristics are most important in choosing the sleeping sites. Black lion tamarins used taller trees, with a fewer canopy connections, and a higher degree of canopy cover compared to the available trees. The sleeping sites used by the continuous forest group were larger, with the first lower ramifications higher and with fewer number of canopy connections than the sleeping sites used by the fragment group. Our results evidenced the presence of anti-predation strategies by both black lion tamarin groups, with the continuous forest group presenting a more refined sleeping site selection process, in which the selection of only trees with a larger set of characteristics can be the result of greater availability of quality resources within the most preserved habitat. (AU)