The Sulawesi bear cuscus (Ailurops ursinus) is an endemic marsupial species inhabiting the island of Sulawesi. In its native region, the animal is also known locally as Bubutu mehmu.
The distribution of the Sulawesi bear cuscus mostly lies within the main island of Sulawesi. Beyond the mainland, populations are also found on several surrounding satellite islands, including Buton Island, Muna Island, the Togean Islands, and Peleng Island in the Banggai Archipelago.
The Sulawesi bear cuscus spends its entire lifespan in trees, which is also known as an arboreal lifestyle. Its living space requires an intact primary and secondary forest canopy. The species inhabits forest ecosystems ranging from coastal lowlands to mountainous areas above 600 meters above sea level.
Physically, an adult Sulawesi bear cuscus weighs between 7 and 10 kilograms, with a body length of approximately 61 centimeters. It is equipped with a prehensile tail that is nearly as long as its body. Its tail supports its body weight while climbing or reaching for young leaves at the tips of branches.
Slow-Paced Life in the Canopy
Ecologically, the Sulawesi bear cuscus is classified as a strict folivore. The species is recorded consuming young leaves from 31 different plant species, encompassing trees, lianas, and mistletoes.
The dietary variety contrasts with the duration of its feeding activity in the wild. Chewing food accounts for only about 5 percent of the bear cuscus's daily activity. The vast majority of its day—around 63 percent—is spent resting on tree branches.
The activity pattern of the species is diurnal, which means it is active during the day. Its characteristic sets the bear cuscus apart from most members of the family Phalangeridae or other cuscus species, which are generally nocturnal.
Natural Vulnerability to Poaching
As an arboreal mammal, the bear cuscus rarely descends to the ground. Interconnected tree branches serve as its primary pathways through the forest. The presence of the species is restricted to areas with dense canopies and minimal human access.
The diurnal habits of the bear cuscus make its presence easily observable from beneath the trees. When facing threats, it cannot escape quickly due to its slow climbing speed.
Those factors leave the bear cuscus vulnerable to poaching. Hunting is carried out for its meat or to capture the animal for the pet trade. The harvesting activity remains a primary factor depressing wild bear cuscus populations.
In addition to poaching, the Sulawesi bear cuscus faces changes in its living space. As an animal that conducts most of its activities high above the ground, it travels across interconnected tree canopies.
Deforestation and forest fires alter the vegetation structure. The loss of trees fragments the bear cuscus's habitat, which steadily reduces its movement range and overall population in its native range.
The International Union for Conservation of Nature (IUCN) lists the Sulawesi bear cuscus as Vulnerable with a decreasing population trend. Meanwhile, at the national level, Ailurops ursinus is listed as a protected species under the Regulation of the Minister of Environment and Forestry No. P.106/2018.
References:
- Nugraha, R., & Marliana, S. N. (2025). A species under siege: modelling habitat suitability for the bear cuscus Ailurops ursinus in South Sulawesi. Oryx, 1–10. https://doi.org/10.1017/S0030605324001406
- Salas, L., Dickman, C., Helgen, K., & Flannery, T. (2019). Ailurops ursinus. The IUCN Red List of Threatened Species 2019. https://doi.org/10.2305%2FIUCN.UK.2019-1.RLTS.T40637A21949654.en
