Moore’s Woolly Lemur, Avahi mooreorum
MOORE'S WOOLLY LEMUR
Avahi mooreorum
Geographic Distribution and Habitat
The Moore’s woolly lemur (Avahi mooreorum), also known as the Masoala woolly lemur, is a species of lemur found exclusively in the northeastern regions of Madagascar, in the province of Antsiranana. It is one of nine recognized woolly lemur species, also called avahis or woolly indris. All lemurs are endemic to Madagascar, and this species is found only in Masoala National Park. They inhabit both dry and wet forests, where they spend most of their day in the high canopy.
The Moore’s woolly lemur is very similar to the eastern woolly lemur (Avahi laniger), with the Moore’s being slightly more lightweight. It was only after DNA sequencing that they were recognized as an independent, separate species.
Size, Weight, and Lifespan
Moore’s woolly lemurs are relatively small, with a head-body length ranging from 11.2 to 13 inches (28.4–33 cm), a tail length of 11.6 to 14.6 inches (29.4–37.2 cm), and a weight of about 2 pounds (920 g). Except for their sexual organs, males and females are visually indistinguishable. Their lifespan is currently unknown.
Appearance
Moore’s woolly lemurs have thick, dark brown fur on their backs with light brown speckles, while their bellies are lighter, tending toward grey. A distinct white patch on the rear surface of their hind legs is the main visual characteristic for identifying this species.
Like other woolly lemur species, they have a characteristic white spot under their chin. Their eyes are round and large, with a yellow-orange hue, and they have a small black nose with curved nostrils.
Diet
Moore’s woolly lemurs are strictly herbivorous. They have a leaf-rich diet, though they also consume buds, fruits, flowers, and bark. Their preferred delicacies are leaves, which they are able to digest thanks to gut microbes. Studies have shown that lemurs possess specialized microbes that help them digest leaves from native trees, making them particularly vulnerable to deforestation, habitat loss, and relocation.
They feed on both young and mature leaves—a rather unusual habit for such small animals, as animals of their size typically lack the evolutionary adaptations needed to process leaves, which are often high in toxins. Among the various trees they consume, the dragon’s blood tree appears to be a favorite.
It’s amazing how advantageous the ability to digest leaves is, especially in Madagascar’s leaf-abundant habitats. Lemurs have evolved to depend on leaves as a primary food source, reducing competition by thriving on food that many coexisting species avoid due to its toxicity or unpalatable nature.
Behavior and Lifestyle
Moore’s woolly lemurs are nocturnal animals—that is, active at night—and they live most of their lives in trees. They become active when the sun sets, and as soon as they wake up, they groom themselves or their partner before starting their nightly routine of feeding and traveling within their home range. Their large, round eyes are adapted to capturing even the faintest light, helping them navigate at night.
Truth be told, they are not particularly active even during the night. Due to their leafy diet, they spend much of their time resting—partly because leaves are difficult to digest, and partly because their diet is low in readily available nutrients.
They spend most of their time high in the vegetation, leaping from tree to tree and rarely setting foot on the ground. If they need hydration, they absorb dew from the leaves they consume. They often have preferred sleeping sites, where they sleep huddled high in the canopy, against tree trunks and supported by branches.
Predators include birds of prey such as the woolly serpent eagle, Eutriorchis astur, Henst’s goshawk, Accipiter henstii, and the Madagascar harrier-hawk, Polyboroides radiatus, as well as mammals like the fossa, Cryptoprocta ferox.
Moore’s woolly lemurs are social but rarely seen in groups larger than two. They usually form close bonds with a partner. Interestingly, they tend to function as quite autonomous couples—often traveling alone and even sleeping separately on occasion. Their home range is approximately 2.5 acres (1.4 ha). While aggression between neighboring pairs has been observed, such data is limited.
They share their habitat with a variety of species, including mouse lemurs, Microcebus sp., and Scott’s sportive lemurs, Lepilemur scottorum. Among these, Moore’s woolly lemurs tend to occupy higher levels of the canopy and prefer thicker branches to slender twigs. A habit that allows for peaceful coexistence.
Woolly lemurs use vocalizations to maintain contact with their partners. When separated, they emit a whistle-like call to indicate their location. This whistle is also used to guide their partner back to the sleeping nest, although it may also serve as a warning to potential rivals.
Another call, known as “ava hy”—from which the species’ name avahi is derived—has an unclear function. Some researchers believe it supports social cohesion, while others interpret it as an alarm call. Mild alarm signals include snorts and grunts, often triggered by sudden disturbances or directed at human observers.
Grooming is also an important form of communication, used to reinforce social bonds.
Moore’s woolly lemurs lead a relatively secluded life. Rarely are they seen with more than one other individual, typically sticking to their mate and offspring, if present. While they appear monogamous, researchers have not ruled out the possibility of occasional mating outside the bonded pair, although this has not been observed.
Sometimes, different pairs forage together, but these associations are usually short-lived. The gestation period lasts around 5 to 6 months, with births typically occurring in late August or early September. Infants are weaned around six months of age and become independent by one year. Fathers don’t take an active role in raising their children.
The Moore’s woolly lemur feeds on leaves, contributing to the control of overgrown vegetation by acting as natural pruners. Because this species lives in the upper canopy of forests, it helps shape tree branches, allowing sunlight to reach the forest floor. Their activity is essential to forest regeneration and overall ecosystem health.
The Moore’s woolly lemur is classified as Endangered by the International Union for Conservation of Nature (IUCN, 2020), appearing on the IUCN Red List of Threatened Species. The area this species inhabits is severely fragmented and shrinking rapidly. Entire populations are disappearing due to unchecked human activities such as unauthorized logging, agricultural expansion, illegal hunting, as well as frequent hurricanes and wildfires. A shrinking home range, combined with these destructive forces, is having a severely detrimental impact on the species.
Moore’s woolly lemurs are listed in Appendix I of the Convention on International Trade in Endangered Species (CITES), an international agreement between governments whose goal is to ensure that international trade in specimens of wild animals and plants does not threaten their survival.
The Masoala National Park, which is known to host Moore’s woolly lemurs, is a protected area. The population around the Ambodiforaha area is comparatively stronger. Nevertheless, logging remains a serious threat—especially since these lemurs prefer living high in the canopy, making them particularly vulnerable to deforestation.
- Avahi mooreorum Lei, Engberg, Andriantompohavana, McGuire, Mittermeier, Zaonarivelo, Brenneman & Louis Jr., 2008. Retrieved April 5, 2025, from https://www.gbif.org/species/7601079
- Eppley, T.M.E., Borgerson, C., Sawyer, R.M. & Fenosoa, Z.S.E. 2020. Avahi mooreorum. The IUCN Red List of Threatened Species 2020: e.T16971566A115588141. https://dx.doi.org/10.2305/IUCN.UK.2020-2.RLTS.T16971566A115588141.en.
- Fenosoa, Z. S. E.,Sawyer, R. M., Andrianarimisa, A., Razafindraibe, H., Rakotomanana, H. & Donati, G. Height and support use of three sympatric nocturnal lemurs in different habitats varying in disturbance on the Masoala Peninsula. Lemur News, 21(39-43)
- Harcourt, C. (1991). Diet and behaviour of a nocturnal lemur, Avahi laniger, in the wild. Journal of Zoology, 223(4), 667–674. https://doi.org/10.1111/j.1469-7998.1991.tb04395.x
- Lei, R.; Engberg, S.E.; Andriantompohavana, R.; McGuire, S.M.; Mittermeier, R.A.; Zaonarivelo, J.R.; Brenneman, R.A.; Louis Jr., E.E. (2008). “Nocturnal lemur diversity at Masoala National Park” (PDF). Special Publications of the Museum of Texas Tech University. 53: 1–48.
- Smith, R. A., & University, D. The surprising reason why some lemurs may be more sensitive to forest loss. Retrieved April 5, 2025, from https://phys.org/news/2019-06-lemurs-sensitive-forest-loss.html
- Woolly Lemurs & where to find them| Madagascar Wildlife & Travel Guides | AQUA-FIRMA Water Wilderness & Wildlife Safaris. Aqua Firma. Retrieved April 7, 2025, from https://www.aqua-firma.com/wildlife/lemurs/woolly-lemur
Written by Mirko Cerrone, April 2025