The diversity of neo-tropical primates is represented by 128 species, with 26 threatened species, 24 of which are endemic of Brazil. Of these threatened primates, 15 species occur in the Atlantic Forest, indicating an alarming state of conservation due to anthropogenic factors. Mata do Paraíso, the largest fragment of this biome in Viçosa, Minas Gerais, comprises an area of 384.5 ha, whose primate population is represented by Callicebus nigrifrons (Spix, 1823), known by titi monkey, and Callithrix sp., denominated marmosets. The present study aimed at estimating the density and population size of these species, as well as at determining their abundance in the area. Five linear 1 km transects, placed in a parallel fashion in a representative portion of the forest, were covered by following the premises of the methodology Distance for linear transects. The data were collected from August 2004 to February 2006, with 70 samplings, totaling 82.7km being sampled, with 24 primate detections. A density of 4.51groups/km² for Callicebus nigrifrons and 7.45groups/km² for Callithrix sp was obtained. Callicebus nigrifrons' abundance corresponded to 1.43 individuals/10 km sampled, and the abundance of Callithrix sp. corresponded to 1.17 individuals/10 km sampled. The population size of Callicebus nigrifrons was estimated in 28 individuals and for Callithrix sp., in 86 individuals. This result corroborates the need for further research to detect fluctuations along time, aiming to preserve and manage these species.
Primates; density; population size
