Avahi laniger (Gmelin 1788)

The eastern woolly lemur typically lives in monogamous pairs, but small groups of up to five related individuals have also been reported (4) (6). As a nocturnal and arboreal species, pairs or groups usually pass the day sleeping huddled together in thick foliage, several metres off the ground (2) (4) (6). Just after dusk, the pairs normally spend some time grooming, before going off to forage alone in the tree canopy, all the while maintaining contact through regular high-pitched whistles. Most foraging activity occurs in the first and last two hours of darkness, with the time in between normally spent resting and grooming (2) (4). When resting, it assumes a characteristic vertical posture by clinging to upright tree limbs and trunks (2) (4) (6). Leaves comprise the vast bulk of this species' diet, but very occasionally it will also take fruits and flowers (2) (4). Mature females are thought to be capable of producing a single infant each year, around August and September (4). Initially the young cling to the female's belly, but when older are transported on the back (2) (4).

In addition to being listed on Appendix I of CITES, which prohibits trade in the species except under exceptional circumstances, the eastern woolly lemur is present within several protected areas, including at least five national parks and two special reserves (1) (2) (3) (4). One of the main priorities for the conservation of this species is to resolve the uncertainty surrounding the taxonomic status of Avahi populations in Ankarana and the Kalambatritra Special Reserve (1).

While the common name of the woolly lemurs refers to their thick, tightly-curled fur, the generic name is an interpretation of their high-pitched defensive call, ava hee. Like all species in the genus, the eastern woolly lemur possesses a long, thin tail and elongated, powerful hind limbs that enable it to leap spectacular distances from one vertical perch to another (2) (4) (5). The upperparts of its body are grey-brown to reddish, becoming paler towards the rump, with the tail being noticeably rufous. The chest and abdomen are a much paler grey, while the backs of the thighs have conspicuous and highly distinctive white patches (2) (4). A small rounded head, large eyes and mostly hidden ears gives its face an almost owl-like appearance (4). Originally, Avahi laniger was split into two subspecies, but in 1990, the slightly smaller and paler, western woolly lemur was elevated to full species status as Avahi occidentalis (2) (4).

Found in tropical moist lowland and montane forest, and in secondary forest (1) (2) (4).

In the wake of recent genetic studies, and the description of several new species of Avahi, the exact distribution of the eastern woolly lemur has become unclear (1). In the past, the species' range was thought to extend the entire length of Madagascar's eastern rainforests, from the extreme south, possibly right up to the island's northern tip (1) (2) (4). However, the most recent distribution given for the species shows it as occurring only in the northern half of the island (1).

Classified as Least Concern (LC) on the IUCN Red List (1) and listed on Appendix I of CITES (3).

Although the eastern woolly lemur population is probably declining in response to habitat loss caused by logging and slash-and-burn agriculture, it is still relatively widespread and common. Furthermore, its nocturnal habit makes it less vulnerable to hunting, compared with many of the diurnal lemur species in the Indriidae family (1) (2) (4).