Social and nonsocial behaviours of sex- and age-matched enclosed and free-ranging rhesus monkeys (Macaca mulatta).

The behavioural profiles (time budgeting of social and nonsocial activities) and the frequencies of major social interactions of corral-enclosed rhesus monkeys were compared with sex- and age-matched free-ranging rhesus monkeys on La Cueva Island, Puerto Rico. All animals (n = 32) were provisioned ad libitum at specific feeder sites. The occurrence of 14 behaviours around feeders was compared with their occurrence away from the feeders by noting the location of each monkey relative to the feeder at the time of observation. An analysis of variance between free-ranging versus corral-enclosed groups and within groups by location (around or away from the feeder) revealed significant differences in several behavioural categories, including foraging, lookout, inactive, dominant, submissive, allogrooming, social contact, social initiative, active, and passive behaviours. When the effect of limited food distribution sites was analyzed by comparing data recorded away from the feeding sites, there were remarkably few differences between the groups.