By Pam Ehler
Geographic Range
Woolly lemurs are found only on the northwest and eastern sides of the island of Madagascar, off the southern coast of Africa.
(Harcourt and Thornback, 1990; Wolfheim, 1983) (Harcourt and Thornback, 1990; Wolfheim, 1983)
Other Geographic Terms:
island endemic 
.
Habitat
(2624 to 6560 ft)
Avahi laniger is found in tropical regions. The population found in western Madagascar (A. laniger occidentalis) occupy dry seasonal forest where the elevation varies. In east Madagascar, A. laniger laniger occurs in a humid coastal forest at lower elevations.
(Flannery, 2000; Nowak, 1991; Parker, 1990) (Nowak, 1991; Parker, 1990; Wisconsin Regional Primate Research Center and University of Wisconsin - Madison, 2001a)
These animals are found in the following types of habitat:
tropical ; terrestrial .
Terrestrial Biomes:
rainforest ; scrub forest .
Physical Description
(21.12 to 45.76 oz; avg. 33.44 oz)
(11.81 to 17.72 in; avg. 14.76 in)
Avahi laniger typically weighs between 600 and 1,300 g. Head and body length varies between 300 and 450 mm.
Woolly lemurs are typically grey-brown or reddish-brown in color, but color varies within the species. Th forearms, hands, legs, and feet are white and the tail is reddish-orange. The fur is thick and woolly (hence the common name), unlike other members of the family Indriidae, which have silky fur. Woolly lemurs have a spherical face which is covered in short hairs, their small ears are concealed within the woolly fur. Avahi laniger has large eyes and a short snout, and a characteristic white stripe that goes up the thigh. Sexes are similar, and it is nearly impossible to distinguish between males and females from a distance, though males have slightly larger molars and skulls. The lower incisors of woolly lemurs are modified into comb-like structure.
(Nowak, 1991; Parker, 1990) (Nowak, 1991; Parker, 1990)
Some key physical features:
endothermic ; bilateral symmetry .
Sexual dimorphism: male larger.
Reproduction
These interbirth interval of these animals is not known.
Breeding occurs from March to May.
Like many mammals on Madagascar, male and female A. laniger seem to mate for life. Couples stay together, raise their young, and live as a family.
(Parker, 1990) (Parker, 1990)
Mating systems:
monogamous .
Breeding occurs from March to May, followed by a gestation of approximately 135 days. Infant woolly lemurs are born during August and September and develop slowly. The baby stays with its mother and is weaned the following wet season. The time to weaning averages 6 months. Other members of the family Indriidae become independent after about 2 years of age.
(Nowak, 1991; Jolly, 1984)
Key reproductive features:
iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization ; viviparous .
Although it is the mother that does most of the care for infant woolly lemurs, the father stays close by. Males have never been seen with a clinging infant.
Infants are dependent upon the mother until they are fully capable of feeding and traveling on their own. From birth to about 2 months, the infant is carried crosswise on the mothers' front side, and nurses 3 to 4 times a day in lengthy sessions. The mother situates herself in a comfortable position to settle down for an afternoon nap and feed her young. As the infant gets older, it moves from being carried on the front to the back and then begins to slowly venture away from the mother.
Feeding behavior begins incidental to play. Young begin playing with the food that the mother is eating, and casually gnaw on the twig or fruit. Thus they gradually learn which foods are safe and good to eat.
At this age, infants become more aware of the surrounding environment by grasping onto nearby branches. By 6 months, the now-weaned infant learns to leap from branch to branch following its mother. Infants do occasionally fall, sometimes up to 30 feet. In a few more months, they learn how to judge distances and make difficult leaps. At one year of age infant woolly lemurs become independent, although the mother is still close by. Even at 2 years of age, the relationship between mother and child is relatively close.
(Harcourt, 1991; Jolly, 1984; Nowak, 1991) (Harcourt, Apr 1991; Jolly, Oberle, and Albignac, 1984; Nowak, 1991)
Parental investment:
altricial ; pre-fertilization (provisioning, protecting: female); pre-hatching/birth (provisioning: female, protecting: female); pre-weaning/fledging (provisioning: female, protecting: female); pre-independence (provisioning, protecting: female); post-independence association with parents; extended period of juvenile learning.
Lifespan/Longevity
Little is known about the lifespan of A. laniger. They are reportedly unsuccessful in zoos, living no longer than three months in captivity outside of Madagascar. However, other members of the family Indriidae are reported to live over 23 years in captivity. It is reasonable to assume that A.laniger has a similar potential lifespan.
(Parker, 1990; Tattersol and Sussman, 1975; Nowak, 1991) (Nowak, 1991; Parker, 1990; Tattersol and Sussman, 1975)
Behavior
Woolly lemurs are nocturnal. They use vertical clinging and leaping as a means of locomotion. When they descend from trees, they stand erect and leap with both feet together holding their arms up in the air much like other lemurs and sifakas.
Because of the low nutritive value of their diets, woolly lemurs are unable to maintain high levels of energy. These lemurs spend long periods of time sleeping. They are highly social animals, forming particularly close and long-lasting family ties.
(Harcourt, 1991; Nowak, 1991) (Harcourt, Apr 1991; Nowak, 1991)
Home Range
Group ranges of eastern woolly lemurs (A. laniger laniger) are 1 to 2 ha in size and do not overlap, indicating some degree of territoriality. This is not the case in western woolly lemurs (A. laniger occidentalis), where home ranges may reach 4 ha. (Harcourt, Apr 1991; Nowak, 1991)
Communication and Perception
As in other primates, it is likely that these animals use a variety of modalities of communication. Vocal communication has been reported. In addition, tactile communication, especially within the family unit, is expected. Visual communication, in the form of body postures and gestures probably also occurs.
Food Habits
The diet of A. laniger is very similar to that of the closely related species Indri indri. The two species are able to live in the same area and share the same diet because they have different activity periods. Avahi laniger is active at night, whereas I. indri is a diurnal species. Although woolly lemurs have been known to eat flowers and fruits, their diet consists mainly of young leaves. They eat only the leaf blade, leaving the midrib and petiole behind.
One male A. laniger studied by Harcourt (1991) made some interesting feeding actions. The male often went to the end of a branch to pick leaves, then returned to the main trunk to eat them. He was also seen eating bits off leaves that remained attached to the tree.
(Cowlishaw & Dunbar, 2000; Harcourt, 1991)
Avahi laniger eats the leaves, buds, and twigs of: Harongana, Hafotra malady, Bararata, Hafidahy, Varongy, Voara, Herodrano, Fatsikahitra, Tavolarano petite feuille, Tavolomalady, Malambovany, Rotra madinika, Rahiaka, Mahanoram, Sary, Karambitoma, Rotra and Fohaninasity. (Cowlishaw and Dunbar, 2000; Harcourt, Apr 1991)
Plant Foods:
leaves; fruit; flowers.
Predation
- humans (Homo sapiens)
- owls (Strigiformes)
- Henst's goshawks (Accipiter henstii)
Woolly lemurs are small and secretive, protecting them from some predators. Their primary wild predators are Henst's goshawks, which find them while resting on exposed branches during the day.
(Flannery, 2000; Harcourt & Thornback, 1990; Wolfheim, 1983) (Harcourt and Thornback, 1990; Wisconsin Regional Primate Research Center and University of Wisconsin - Madison, 2001a; Wolfheim, 1983)
Ecosystem Roles
Woolly lemurs act as a prey species for several predators, including humans. Through its folivory, A. laniger may influence plant composition in the forests where they live.
(Flannery, 2000) (Wisconsin Regional Primate Research Center and University of Wisconsin - Madison, 2001a)
Economic Importance for Humans: Negative
None known
Economic Importance for Humans: Positive
Although A. laniger is an endangered species, it is still hunted for food by Malagasy people.
(Harcourt & Thornback, 1990) (Harcourt and Thornback, 1990)
Ways that people benefit from these animals:
food .
Conservation Status
IUCN Red List: [link]:
Lower Risk - Near Threatened.
US Federal List: [link]:
Endangered.
CITES: [link]:
Appendix I.
Woolly lemurs are a species of great concern in conservation efforts, as are many other species in the Lemuridae and Indriidae families. This concern is mainly due to the considerable amount of habitat loss in Madagascar's tropical rainforests. Although this island known for extraordinary levels of endemic biodiversity and conservationists are working hard to protect lemur species, habitat loss and the hunting of lemurs for food continues at a rapid pace.
(Harcourt & Thornback, 1990; Nowak, 1991) (Harcourt and Thornback, 1990; Nowak, 1991)
Other Comments
There are two subspecies of A. laniger: Avahi laniger laniger is found in eastern Madagascar, and A. laniger occidentalis is found in northwestern Madagascar. The two subspecies are so similar that some researchers do not consider them to be distinct, though some behavioral differences have been noted.
(Flannery, 2000; Tattersall & Sussman, 1975) (Tattersol and Sussman, 1975; Wisconsin Regional Primate Research Center and University of Wisconsin - Madison, 2001a)
For More Information
Find Avahi laniger information at
Contributors
Nancy Shefferly (editor), Animal Diversity Web Staff.
Pam Ehler (author), University of Northern Iowa.
Jim Demastes (editor), University of Northern Iowa.
