Reproduction
A blue-eyed lemur female infant riding on her mother's belly. Click image for larger version.
Blue-eyed lemurs, like all diurnal lemurs, are seasonal breeders. In Madagascar, the breeding season ranges from April to June. In northern hemisphere locations, such as the DLC, most breeding occurs in November and December with births in March and April. During breeding season, both males and females experience physiological changes. By the time the females are approaching estrous, the testicle size of the males has become notably larger, and the males are becoming more aggressive towards and less tolerant of their fellow males.
In the wild, female blue-eyed lemurs give birth to one or two offspring in the fall, after a gestation period of approximately 126 days. It is possible for two females in the same group to become pregnant during the same breeding season. After successfully giving birth, mothers might immediately become very aggressive to other members of their group, threatening them and lunging at them if they come too close. After a few days or a week of guarding the infants, Juveniles are typically granted first access to the newborns, followed by the father, and later the other adult females in the group.
Although dichromatic as adults, both male and female blue-eyed lemurs are born with the same dark brown to black coloration. Infants cling to their mothers' bellies for the first 3 weeks, shifting position only to nurse. At three to four weeks of age, the young lemurs will begin to make short explorations of a foot or two away from their mother, quickly scurrying back to the safety of her belly at the first sign of danger. Infants begin to explore solid food at 4-6 weeks of age, sampling bits of whatever their mothers or other nearby group members are eating. Nursing continues, but with a steady decline in importance in the infant's diet, until the infant is weaned at 5 - 6 months of age.