Social Behavior
Family group of red-bellied lemurs (with male in the center) in the forest. Click image for larger version.
In the wild, red-bellied lemurs are found in family groups of two to six. Groups consist of an adult pair and their immature offspring. Studies in Ranomafana National Park in Eastern Madagascar have demonstrated that red-bellied home ranges in Madagascar average only around 20 hectares, quite small by typical large-bodied lemur standards. The entire home range is utilized on a daily basis, the borders are approached everyday and are actively defended against intrusion by neighboring groups-- making these animals one of the more territorial lemurs.
At the DLC juveniles remain within their family group until the age of two and a half or three, when sexually mature males are ejected by their fathers and females ejected by their mothers. Parents eject their young from the group whether the animals are housed in a small cage or a multiple acre enclosure. Since the home range size of this lemur in the wild is too small to support a large group of animals, it follows that juveniles would be "encouraged" by their parents to strike out on their own. Ejections of juveniles can be quite violent affairs, so Primate Technicians at the DLC in charge of red-bellied lemur family groups closely monitor tension levels in their groups.