White-eared titi of 11.5 hours, 2.7 hours of which is spent feeding. Titi monkeys sleep on branches at least above the ground. In the same manner as resting during the day, titi monkeys huddle together and twine tails to sleep. Though there is little published research on the diet of the white-eared titi, titi monkeys in general are omnivores that eat fruit, leaves, insects, and seeds. They mostly eat leaves, especially protein-rich young leaves and leaf buds, so a significant period of the day is spent resting to digest the cellulose. They consume more than 100 different species of plants and fruit.
Coimbra Filho's titi preferred habitat for Coimbra Filho's titi consists of densely wooded areas, preferring the dense understory and lower canopy. However, it is able to survive in damaged or fragmented forests, which currently comprise a large portion of its range. This is due to a tolerance to highly disturbed areas, as well as the ability to subsist in areas composed primarily of young or second growth forests. While other species in "Callicebus" are native to many areas of South America from Colombia to Brazil, Peru and north Paraguay, Coimbra Filho's titi is found only in a very small area in the states