can be found in other forest habitats, both primary and secondary, such as riparian (near fresh or brackish water), gallery, and upland forests. It is particularly common in forests close to rivers and lakes and at high elevations. It can be found in elevations as high as . This species prefers secondary forests and selects them over old-growth forests if given the choice. It is likely that the mantled guereza prefers these forests due to the increased number of food trees and the weaker chemical defenses of the species within. The mantled guereza is sometimes found in swamps as well as human-made habitats such as Eucalyptus plantations, which may be frequented when the monkey has nutritional deficiencies. Ecology The mantled guereza is primarily arboreal, but does sometimes descend on the ground to forage and travel, perhaps more so than most other colobines. It is diurnal and rests for up to half the day. Foraging or travelling are the next most common activity. Sometime after dawn, mantled guereza groups leave their sleeping trees and will return to them at dusk. During the day, the mantled guereza has long rest periods in between periods of moving and feeding. Other activities, including grooming, greeting, playing and being vigilant, are performed to a lesser extent. Despite its reputation as an exclusive leaf-eater, the mantled guereza is not an obligate folivore. While it mainly eats leaves and fruit, its diet is quite variable. It may eat bark, wood, seeds, flowers, petioles, lianas, aquatic-plants, arthropods, soil, and even concrete from buildings. The amount of each food item in its diet varies by area and time of year. Nutritional factors like protein, tannins, and sodium levels in leaves influence its food choices. It may even intermittently travel longer distances to access plants with higher levels of nutrition. Leaves usually make up over half of its diet, although fruits are occasionally eaten more depending on the season. When foraging for leaves, the mantled guereza prefers young ones over old. With fleshy fruits, the mantled guereza prefers to eat them unripe, which may serve to reduce competition with primates that eat ripe fruits. It consumes a number of plant species but only some make up most of its diet at a specific site. Like all colobi, the mantled guereza is able to digest leaves and other plant fibers with a large, multi-chambered stomach that contains bacteria in certain areas.