Progression is by walking or running on larger branches, and leaping from tree to tree. Locomotion is more labored and cautious than with other Lemur species. Vocalizations include an intense roar of alarm, and a powerful, plaintive call for territorial expression. Group sizes can range from 2 to 16. All group members use a common home range, and aggression has been noted between groups.
Females form the core of the group, and defend the territory.
The weakest social bonds are between males. Grouping patterns change seasonally. Females group in larger numbers during the wet summer, and are more dispersed during the drier winter. The young are usually born in September and October. Infants are at first left in the nest, rather than being carried about by their mothers.