Activity pattern of the masked titi monkey,Callicebus personatus
A group of six masked titi monkeys was studied at the Sooretama Biological Reserve, Espírito Santo, Brazil. The family group consisted of adult male and female, three juvenile-subadult offspring, and an infant carried by the father. Two patterns of activity were identified: one in which two major feeding peaks were separated by a single long rest period and a relatively long travel distance between the two major feeding sites; and a second in which three major feeding peaks were separated by rest periods and travel was more evenly dispersed throughout the day.Callicebus personatus was similar toC. moloch in the folivorous supplementation of its frugivorous diet, and in having marked daily peaks in feeding and resting activities.C. personatus was similar toC. torquatus in the location of sleeping position on a large open bough, and the habit of calling from well within the territorial boundary. All three species are known to live in monogamous family units with parental care by the adult male, defend territories with loud intergroup vocalizations, and feed primarily upon a small number of widely dispersed fruits.