Time budget of Tana river red colobus

Data on the activity pattern of a group of red colobus monkeys (Colobus badius rufomitratus) living along the Tana river, Kenya, were collected during monthly 5-day observation periods between October 1973 and December 1974. The two most important activities were feeding and resting which occupy about one-third and one-half of daytime, respectively. These proportions vary considerably, however, according to age-sex class, time of day and month of year. Compared to a group studied at a rain-forest site in Uganda, the Tana animals spend substantially less time feeding and more time resting. Possible reasons for this difference are discussed.