Habitat use, fruit consumption, and population density of the black-headed night monkey, Aotus nigriceps, in Southeastern Peru

Abstract

The study of wild black-headed night monkey (Aotus nigriceps) ecology is limited to a single field station, despite the species being found across a vast distributional range in the Amazon.We studied several aspects of their ecology, specifically habitat use, group size, population density, and diet. All sampled groups were found in secondary tropical rainforest, often dominated by either native bamboo or cane species. Sleeping sites were often in bamboo stands, though groups were also found in cane thickets and lianas. This is in contrast to other Aotus studies which have found groups living in tree cavities and lianas. Population density estimates varied between field sites (19 and 50 individuals per km 2 ), but both were consistent with other Aotus studies (31-40 individuals per km 2 ). And, twelve seed species were recovered from fecal samples over the course of two field seasons, dominated primarily by Cecropiaceae, Piperaceae and Moraceae. Our results suggest that the black-headed night monkey can survive and even