Sleeping sites of common marmosets (Callithrix jacchus) in defaunated urban forest fragments:: a strategy to maximize food intake

The purpose of this study was to investigate if there was any species-specific type and structure of sleeping sites of common marmosets Callithrix jacchus and their key determinant. The study was conducted in an urban fragment of the Atlantic forest of north-eastern Brazil, where a group of common marmosets was followed for 488 h. For this purpose we used ad lib observations, performed twice a week, when the animals were entering and leaving the sleeping sites, identified potential predators of the common marmosets through interviews with local people, and identified the trees that provided them with fruit and/or exudate during the study. Five sleeping sites were identified, all invariably in the border of the native forest and the orchard. No predators of common marmosets were seen by local people or recorded during this study, and the sleeping trees were located invariably in the place where there was the highest concentration of feeding trees, regardless of its structure. There was no species-specific type and structure of sleeping places of common marmosets. The key variable defining the choice of a sleeping place was the availability and location of immediate sources of food.