Bear Cuscus

Observations: Little is known about these animals and few have been kept in captivity. One specimen lived 5.9 years at Berlin Zoo before it died in 1937 (Richard Weigl 2005).

Ailurops ursinus is the most primitive and plesiomorphic of all phalangerids, and is thus placed in a separate subfamily, Ailuropinae. It is hypothesized that A. ursinus was isolated on the island of Sulawesi when the island first emerged in the Miocene, accounting for the animal's morphological divergence from the rest of the family Phalangeridae.

(Flannery et al, 1987; George, 1987)

Perception Channels: tactile ; chemical

Under the name Phalanger ursinus, A. ursinus has protected status in Indonesia. Hunting greatly threatens this animal because of its low reproductive rate, particularly because females with young in the pouch may be killed and the young then abandoned, almost certainly dying.

(The Indonesian Nature Conservation Database, 2000; National Wildlife Federation, 2000; Lee, 2000)

US Federal List: no special status

CITES: no special status

IUCN Red List of Threatened Species: vulnerable

Although not much sought-after, the meat of A. ursinus is still commonly found in the restaurants and markets of Indonesia.

(Lee, 2000)

Positive Impacts: food

Although primarily a folivore, Ailurops ursinus also consumes unripe fruit, flowers and buds. These have not yet completed the development necessary in order to be able to give rise to another plant. Thus, the bear cuscus tends to restrict the reproductive potential of some plants.

Ailurops urisinus eats the leaves of many different tree species, but three make up half of the total diet. Young leaves are much preferred, probably because they are easier to digest and contain fewer toxins. However, the bear cuscus prefers mature leaves of mistletoes, which have more protein than the young leaves. A small amount of flowers and unripe fruit (which contains more protein than ripe fruit) are also eaten.

Common foods eaten include: tree leaves (Garuga floribunda, Melia azedarach, Dracontomelum dao), mistletoe leaves (Cananga odorata, Palaquium amboinense), unripe fruit, flowers and buds.

(Dwiyahreni et al, 1999; Lee, 2000)

Plant Foods: leaves; fruit; flowers

Primary Diet: herbivore (Folivore )

Ailurops ursinus is found only on Sulawesi and the Talaut Islands of Indonesia.

(George, 1987; USGS, 1996)

Biogeographic Regions: australian (Native )

Other Geographic Terms: island endemic

Ailurops ursinus is an arboreal marsupial that lives in the upper canopy of lowland tropical rainforests.

(Dwiyahreni et al, 1999; Lee, 2000)

Habitat Regions: tropical ; terrestrial

Terrestrial Biomes: rainforest

Ailurops ursinus has a short face and short, furry ears. The pelage is composed of a fine, wiry underfur and coarse guard hairs. Coloration ranges from black to grey to brown with a lighter colored belly and tips of extremities, with variation depending on geographic location and age of the animal.

The prehensile, unfurred tail is half of the total body length and is used in conjunction with the forefeet (which have two opposable digits) and syndactylous hindfeet to move between trees. Ailurops ursinus is the most primitive of all phalangerids, retaining primitive dentition and cranial features.

(George, 1987; Nowak, 1997; Myers, 1999; National Wildlife Federation, 2000)

Average mass: 7 kg.

Range length: 1.2 (high) m.

Other Physical Features: endothermic ; bilateral symmetry

Average mass: 7000 g.

Mating system and behavior is unknown.

(Hayssen et al, 1993)

An adult female A. ursinus gives birth one or two times a year.

(Lee, 2000)

Range number of offspring: 1 to 2.

Average weaning age: 8 months.

Key Reproductive Features: gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization (Internal ); viviparous

Young are born at an extrememly altricial stage and continue development in the mother's pouch. After eight months, development is sufficient to allow survival, although the young remains with the mother for an additional period. It is unknown at what age Ailurops ursinus reaches developmental maturity.

(Lee, 2000)

Parental Investment: altricial ; female parental care

The bear cuscus is the most primitive phalangerid, retaining primitive dentition and cranial features(4,6-8).

It occurs on the island of Sulawesi, Indonesia, and the adjacent Indonesian islands of Butung, the Peleng, Togian and Talaut Islands and possibly Muna (3-5). It ranges from sea level to over 600 m above sea level. It is typically found in the upper canopy of undisturbed tropical or subtropical lowland moist forests (2,9,10). It does not readily use disturbed habitats, so is not usually found in gardens or plantations.

It has an an average mass of 7 kg and is up to 1.2 m long. It has a short face and short, furry ears. The prehensile, unfurred tail is half of the total body length and is used in conjunction with the forefeet, which have two opposable digits, and syndactylous hindfeet to move between trees. The pelage is composed of a fine, wiry underfur and coarse guard hairs. Coloration ranges from black to grey to brown with a lighter colored belly and tips of extremities; variation depends on geographic location and the age of the animal.

It is largely diurnal and arboreal and is often found in pairs. It feeds on various leaves; the leaves of three species of trees make up half the total diet. Young leaves are much preferred, probably because they are easier to digest and contain fewer toxins. The cuscus prefers mature leaves of mistletoes, which have more protein than young leaves. It also eats a small amount of flowers, buds and unripe fruit (which contains more protein than ripe fruit) (9,10) . As it eats buds, it tends to restrict the reproductive potential of some plants.

An adult female gives birth to 1-2 young 1-2 times a year (1). The young are born at an extrememely altricial stage and continue development in the mother's pouch. They are weaned at @ 8 months, after which development is sufficient to allow survival, although the young stays with the mother for an additional period. One specimen lived 5.9 years at Berlin Zoo (11).

The Red List Category is Vulnerable, due to an ongoing population decline estimated and projected to exceed 30% in a 10 year period, due to the high rate of deforestation using large-scale logging for agriculture. The cuscus, under the name Phalanger ursinus, has nominaly protected legal status in Indonesia. Hunting and the pet trade greatly threaten it due to its low reproductive rate, particularly as females with young in the pouch may be killed and the young then abandoned, almost certainly dying (8,10,12). The meat is commonly found in restaurants and markets of Indonesia (10). The cuscus is abundant in some areas, but was much more plentiful. From 1979-1994, there was a 95% decline in Tangkoko-DuaSudara Nature Reserve due to hunting and this may be indicative of trends for North Sulawesi (13). It occurs in many protected areas, including: Tangkoko-DuaSudara Nature Reserve, various forest reserves and the Bogani Nani Wartabone, Lore Lindu and Morowali National Parks.

The Sulawesi bear cuscus, also known as the Sulawesi bear phalanger (Ailurops ursinus), is a species of arboreal marsupial in the family Phalangeridae that is endemic to Sulawesi and nearby islands in Indonesia. It lives in tropical moist lowland forest at elevations up to 600 m (2,000 ft) and is diurnal, folivorous and often found in pairs. A. ursinus is threatened by hunting, collection for the pet trade and deforestation.

When approached, their automatic reaction is to wrap their tail around a nearby branch and switch from tripedal and bipedal posture with their foreleg raised. While doing these movements, they're constantly making short, harsh sounds.

Bear cuscuses can feed on the young leaves of up to 31 different species of plants varying from trees, lianas, and mistletoes. Feeding only amounts to about 5% of their daily activity, compared to about 63% spent on resting.