Reproduction
A black and white ruffed lemur mother guards her infant in their nest. Click image for larger version.
Ruffed lemur reproduction is highly seasonal. The animals breed in Madagascar between May and July. Most infants are born, after a 102 day gestation, in September and October. In North Carolina, breeding usually occurs in December or January with births in April or May.
Ruffed lemur females give birth to litters of up to six infants (two or three is more typical) in well-concealed, well-constructed nests 10 to 20 meters up a tree. Varecia are the only diurnal primates in the world to keep their infants in a nest. Females can nurse up to six infants simultaneously. Infant ruffs are not as well developed at birth as other species, which is not surprising given the brief gestation period.
At birth, infants are not capable of grasping the mother, so if she needs to transport them, she must pick them up and move them one at a time in her mouth. The mother generally moves her infants away from the nest after a week or two, at which point she leaves them parked in a tree while she forages nearby. Infants develop rapidly, and by three or four weeks they can attempt to follow their mother on their own. Not surprisingly, infant mortality appears to be very high for this species, with 65% of infants failing to make three months of age, due to accidental falls and related injuries.