Where Do Sun Bears Live? Tropical Forests Across 11 Southeast Asian Countries

Where do sun bears live?

Sun bears (Helarctos malayanus) live in the tropical and subtropical forests of Southeast Asia, across 11 range countries: Bangladesh, India (northeast), Myanmar, China (Yunnan), Laos, Thailand, Vietnam, Cambodia, Malaysia (peninsula and Borneo), Indonesia (Sumatra and Borneo), and the small Bornean sultanate of Brunei. The core habitat is lowland dipterocarp rainforest below 1,200 metres, with hill and mountain populations reaching 2,800 metres in Sumatra. The wild population is estimated at 25,000 to 50,000 individuals and has declined by 30 to 50 percent over the past 30 years.

A Bear of the Tropical Lowland Forest

Walk into the dipterocarp forest of Danum Valley in Sabah just before dawn, when the night-shift cicadas have gone silent and the gibbon chorus is still ten minutes away, and you are walking through the heart of sun bear country. Old claw marks score the trunk of an Aglaia tree at chest height. A torn-open termite mound sits at the base of a fallen log. Twenty metres up, in the crown of a fruiting strangler fig, a small black bear with a cream-coloured chest patch is hauling fruit toward its mouth, sixty kilograms of carnivore balanced on a branch the thickness of a wrist.

The sun bear is the only bear that lives its entire life in the tropics, the only one with a fully arboreal lifestyle, and the smallest of the eight living bear species. For a complete species overview see the main sun bear profile. This guide narrows the focus to a single, surprisingly tangled question: where, exactly, does this animal still live?

The simple answer is Southeast Asia. The full answer is a 4,000 kilometre arc of lowland rainforest, peat swamp, and hill forest that crosses 11 countries, two great islands, and one of the most rapidly transformed landscapes on Earth.

The 11 Countries of the Sun Bear

The species range traces the Indo-Malayan region from the eastern fringe of the Indian subcontinent through mainland Southeast Asia and onto the Sunda Shelf islands. From north and west to south and east, sun bears are recorded in:

Bangladesh, in the Chittagong Hill Tracts (status uncertain, possibly extinct)
India, in the northeastern states of Assam, Arunachal Pradesh, Manipur, Mizoram, Nagaland, and Tripura
Myanmar, throughout the country in remaining forest blocks
China, in southern Yunnan province at the Lao and Myanmar border
Laos, across the Annamite range and the northern uplands
Thailand, in protected areas including Khao Yai, Khao Sok, and the Western Forest Complex
Vietnam, in southern protected forests including Cat Tien and Yok Don
Cambodia, in the Cardamom Mountains and the eastern plains forests
Malaysia, on peninsular Malaysia and across Sabah and Sarawak on Borneo
Indonesia, on Sumatra and across Kalimantan on Borneo
Brunei, in the Bornean rainforests of Belait, Tutong, and Temburong

The species is absent from the Philippines, Java, Sulawesi, the Lesser Sundas, and from the Himalayan foothills above the tropical forest line. Bangladesh sits at the northwestern edge of historical range and may now have lost its last bears, although verification is difficult because surveys have not been completed since the early 2000s.

The sun bear is the most poorly studied of the world's eight bears. We have an idea of where they should be from forest cover maps, but on the ground they are vanishing from places we still draw on the range map. — Siew Te Wong, founder of the Bornean Sun Bear Conservation Centre

For the broader picture of how sun bear conservation interacts with the forest economy, see the sibling article Sun Bear Conservation: Bile Farming and Deforestation.

Population by Country

Sun bear numbers are notoriously hard to pin down. The species is shy, low density, often arboreal, and lives in forest interiors that defy systematic line transect counts. Most country totals come from a combination of camera trap arrays, sign transects, occupancy modelling, hunter interviews, and expert elicitation. The IUCN Bear Specialist Group declines to publish a single global figure, instead presenting a range from roughly 25,000 to 50,000 individuals.

Table 1: Estimated sun bear population and status by country

Country	Estimated bears	Primary range	Trend
Indonesia (Sumatra + Kalimantan)	~12,000 to 20,000	Lowland and hill rainforest, peat swamp	Declining
Malaysia (Sabah + Sarawak + Peninsula)	~5,000 to 8,000	Bornean dipterocarp forest, peninsular reserves	Declining
Myanmar	~3,000 to 6,000	Tanintharyi, Hukawng, Sagaing	Declining
Laos	~1,500 to 3,000	Annamite range, Nakai-Nam Theun	Strongly declining
Cambodia	~1,000 to 2,000	Cardamoms, Eastern Plains landscape	Declining
Thailand	~500 to 1,000	Western Forest Complex, Khao Yai cluster	Stable in reserves, declining elsewhere
Vietnam	~150 to 400	Cat Tien, Yok Don, Bach Ma	Strongly declining
China (Yunnan)	~150 to 300	Xishuangbanna, Nangunhe	Strongly declining
India (northeast)	~150 to 500	Namdapha, Dampa, Mizoram-Manipur hills	Declining
Brunei	~100 to 300	Ulu Temburong, Belait	Stable, very small
Bangladesh	possibly 0	Chittagong Hill Tracts	Possibly extinct
Global total	~25,000 to 50,000	Tropical Southeast Asia	Declining (IUCN Vulnerable, decreasing)

Numbers compiled from IUCN Bear Specialist Group assessments, national wildlife agency reports, and peer-reviewed occupancy and camera trap studies. All estimates carry wide confidence intervals.

For context on how this population compares with that of other bears, see where do grizzly bears live and where do spectacled bears live. Sun bears are roughly twice as numerous as Andean bears but cover a much smaller global land area, because tropical lowland forest is far more productive than Andean cloud forest.

The Habitat: Lowland Dipterocarp Rainforest

The defining habitat of Helarctos malayanus is lowland dipterocarp rainforest, a forest type dominated by towering trees of the family Dipterocarpaceae. These trees fruit in mast events every two to seven years, releasing simultaneous superabundances of oil-rich seeds across thousands of square kilometres. Sun bears, like orangutans and bearded pigs, time their reproduction loosely to these mast cycles and concentrate around fruiting Shorea, Dipterocarpus, and Hopea trees during the peaks.

Beyond the dipterocarps, the forest provides:

Wild figs (Ficus spp.) — keystone food across the entire range
Durian, langsat, rambutan, and other Sundaic fruits
Termite mounds of Macrotermes and Globitermes, broken open for the queens and brood
Stingless bee colonies in hollow trees, raided for honey and larvae
Beetle larvae in dead and dying hardwood, accessed by tearing open trunks
Sleeping platforms built of bent branches in the canopy at 10 to 20 metres

The bear's body is built for this forest and almost nothing else. Inward-rotated forepaws hook around vertical trunks. Claws up to 10 centimetres curve back toward the body for vertical traction. A 20 to 25 centimetre tongue probes deep into bee combs and termite galleries. Loose neck skin allows the bear to swivel inside its own coat when threatened by a clouded leopard or tiger. Take the dipterocarp canopy away and the entire toolkit becomes useless. For more on the bear's tropical food specialisation see what do sun bears eat.

Lowland dipterocarp forest is not just where the sun bear lives. It is what the sun bear is made of. The species's anatomy, its tongue, its nest-building, its mast-tracking reproduction, all evolved in that single forest type. The forest goes, the bear goes. — Gabriella Fredriksson, Sumatran sun bear field researcher and IUCN Bear Specialist Group co-chair

Elevation: From Peat Swamp to the Cloud Line

Sun bears are usually thought of as a strictly lowland species, but the truth is more interesting. Across the range the elevation ceiling rises with latitude. On the equator, in Sumatra and Borneo, sun bears can climb well above 2,000 metres because tropical mountains carry warm, productive forest much higher up. On the northern fringe of the range, in Yunnan and northern Myanmar, the ceiling drops to about 1,500 metres because forest above that line becomes too cold and seasonal for the species.

Table 2: Elevation use across the sun bear range

Elevation band	Habitat type	Region	Use intensity
0 to 200 m	Peat swamp, freshwater swamp, lowland dipterocarp	Sumatra, Kalimantan, southern Myanmar	Core habitat, highest densities
200 to 800 m	Lowland and hill dipterocarp forest	All range	Core habitat, highest densities
800 to 1,500 m	Hill dipterocarp, lower montane forest	Borneo, Sumatra, Yunnan, Annamites	Frequent
1,500 to 2,000 m	Lower montane forest	Sumatra (Barisan range), Sabah (Crocker, Trus Madi)	Moderate, seasonal
2,000 to 2,800 m	Upper montane forest	Sumatra (Kerinci, Leuser), Sabah (Kinabalu)	Confirmed, low density
above 2,800 m	Subalpine and grassland	Kinabalu summit zone	Absent

The Sumatran population on the Barisan range, where camera traps have recorded sun bears at over 2,500 metres in Kerinci-Seblat and Leuser, demonstrates that the species can persist at high elevation when the forest itself extends that high. The Yunnan population near Xishuangbanna sits closer to the 1,500 metre ceiling typical of mainland mountains.

For the related question of how a small bear copes with this kind of vertical mobility, see how small is the sun bear, world's smallest bear.

Two Subspecies, Two Islands

Sun bears are currently divided into two recognised subspecies based on body size, skull morphology, and chest patch shape:

Helarctos malayanus malayanus — the mainland and Sumatran form. Larger, with a broad chest blaze.
Helarctos malayanus euryspilus — the Bornean form. Noticeably smaller, with a narrower chest patch and shorter coat.

The Bornean subspecies is restricted entirely to the island of Borneo, distributed across Indonesian Kalimantan, Malaysian Sabah and Sarawak, and Brunei. Some genetic studies suggest the divergence between Bornean and mainland sun bears is deep enough to warrant full species status, although the IUCN currently retains the single-species treatment.

This taxonomic split has practical consequences. A Bornean sun bear and a Sumatran sun bear are separated by the South China Sea and have not exchanged genes for hundreds of thousands of years. Conserving the species means conserving both lineages on both islands, plus the relict mainland populations that may yet hold further unrecognised diversity.

Key Reserves and Strongholds

Sun bears persist mainly inside large protected forest blocks. The following sites anchor the long-term outlook for the species across the range.

Borneo (Sabah, Sarawak, Kalimantan, Brunei):

Danum Valley Conservation Area — Sabah; the type locality for much modern sun bear research
Tabin Wildlife Reserve — Sabah; secondary forest with confirmed breeding population
Kinabalu National Park — Sabah; elevational range from foothill to montane forest
Maliau Basin Conservation Area — Sabah; remote intact dipterocarp forest
Lanjak Entimau Wildlife Sanctuary and Betung Kerihun National Park — Sarawak and West Kalimantan, contiguous transboundary forest
Kayan Mentarang National Park — East Kalimantan, the largest protected forest of Indonesian Borneo
Ulu Temburong National Park — Brunei

Sumatra:

Gunung Leuser National Park — Aceh and North Sumatra; one of the species's strongholds
Kerinci-Seblat National Park — central Sumatra; high-elevation records up to 2,800 metres
Bukit Barisan Selatan National Park — southern Sumatra
Way Kambas National Park — eastern Sumatra; lowland forest with confirmed bears

Mainland Southeast Asia:

Khao Yai, Khao Sok, and the Western Forest Complex — Thailand
Cat Tien National Park, Yok Don, and Bach Ma — Vietnam
Cardamom Mountains and Eastern Plains landscape — Cambodia
Nakai-Nam Theun and Nam Et-Phou Louey — Laos
Hukawng Valley, Tanintharyi, and Htamanthi — Myanmar
Xishuangbanna and Nangunhe — Yunnan, China
Namdapha and Dampa — northeastern India

The Bornean Sun Bear Conservation Centre in Sandakan, Sabah, founded by Siew Te Wong in 2008, is not itself a wild reserve but plays an outsized role in the species's future by rescuing illegally captured bears, conducting research, and rewilding individuals into adjoining Sepilok forest. For the broader story of why so many sun bears end up in rescue, see Sun Bear Conservation: Bile Farming and Deforestation.

The bears we rescue come from cages, kitchens, and bile farms across Sabah and Sarawak. Every one of them is a forest animal. Our job is to put forest back into the bear, and then to put the bear back into the forest. — Wong Hui Min, programme manager, Bornean Sun Bear Conservation Centre

Population Decline: 30 to 50 Percent in 30 Years

The single most important fact about sun bear distribution today is that the range is shrinking fast. The IUCN Red List assessment estimates a global population decline of 30 percent over the past three sun bear generations (about 30 years), with some range states experiencing declines well above 50 percent. The species is listed as Vulnerable, decreasing.

The drivers of decline are well documented:

Oil palm plantation expansion, particularly across Sumatra, Sarawak, and Sabah
Industrial-scale logging of lowland dipterocarp forest
Pulp and paper plantations replacing peat swamp forest in Sumatra
Road construction, which fragments contiguous forest into isolated blocks
Poaching for bile and gall bladder for traditional medicine markets
Cub capture for the pet trade, often after the mother is killed
Snaring, especially the indiscriminate wire-noose snares now epidemic across Indochina

The effect of these pressures is uneven. In Sabah, where logging is regulated and the protected area network is extensive, sun bears are still relatively common in the forest interior. In Vietnam, by contrast, decades of intense snaring have pushed the species to the edge of functional extinction in many former range areas. In Cambodia, a study by the Wildlife Conservation Society in the Eastern Plains landscape found camera-trap detection rates of sun bears falling sharply between the early 2000s and the late 2010s as snaring pressure rose.

The empty forest syndrome is now a sun bear problem. We can fly over Indochina and see canopy that looks intact, then walk in on the ground and find no bears, no ungulates, and no large primates. The forest is the wrapper, not the contents. — IUCN Bear Specialist Group, sun bear status assessment

For comparative ecological context the giant panda profile provides another example of a tropical-to-subtropical Asian bear whose range has collapsed under habitat loss, while are sun bears dangerous addresses the question of how often sun bears come into contact with people in the few places where they still do.

The Mountain Populations

Two mountain populations deserve specific attention because they show that the sun bear is not strictly a lowland species when conditions allow.

The Yunnan population in southern China occupies the 800 to 1,500 metre band of the Xishuangbanna and Nangunhe protected areas. This population is small, fragmented, and increasingly isolated from contiguous range in northern Laos and Myanmar. Population estimates run from about 150 to 300 individuals.

The Sumatran montane population is more substantial. Camera traps in Kerinci-Seblat National Park have recorded sun bears at elevations exceeding 2,500 metres on the slopes of Gunung Tujuh and Gunung Kerinci. In Leuser, individual bears have been confirmed at over 2,800 metres. These records are at or near the upper elevational limit of any tropical bear and demonstrate the species's ecological flexibility when continuous forest extends that high.

Sumatran sun bears at 2,800 metres are not vagrants. They are part of a resident montane population that has probably persisted there since the Pleistocene, when the lowlands periodically flooded and the bears retreated upslope. — Oryx, sun bear distribution review

For the related question of how mothers raise cubs in such varied terrain see Sun Bear Cubs and Mothers.

Why the Range Looks the Way It Does

Three deep biogeographic facts shape sun bear distribution:

The Sunda Shelf. Borneo and Sumatra were repeatedly connected to the Asian mainland during Pleistocene low sea-level periods, allowing sun bears to colonise both islands. The Bornean subspecies has been isolated since the last connection broke roughly 10,000 years ago.
The Tropical Rainforest Climate Belt. Sun bears require year-round fruit and insect availability. They cannot follow the deciduous monsoon forests that extend further north and west, because those forests have a hungry season the bear cannot survive without entering torpor (and sun bears do not hibernate).
The Wallace Line. East of the Lombok Strait the fauna shifts to Australasian lineages and the dipterocarp forest disappears. Sun bears never crossed the Wallace Line and have no presence on Sulawesi, the Moluccas, the Lesser Sundas, or New Guinea.

These three constraints together produce the modern range: a band of dipterocarp-dominated tropical forest stretching from northeastern India and Bangladesh down through mainland Indochina, across the Malay Peninsula, and onto the western islands of the Sunda Shelf, and stopping abruptly at every climate, ocean, and ecological boundary.

A Few Numbers to Hold Together

11 range countries
Total population: 25,000 to 50,000 (highly uncertain)
Decline: 30 to 50 percent over 30 years
Elevation range: 0 to 2,800 metres (Sumatra), 0 to 1,500 metres (Yunnan)
Core habitat: lowland dipterocarp rainforest
Two subspecies: mainland H. m. malayanus, Bornean H. m. euryspilus
Largest population: Indonesia (Sumatra plus Kalimantan combined)
Smallest viable population: Brunei, Vietnam, China (each under a few hundred)
Possibly extinct: Bangladesh

References

Scotson, L., Fredriksson, G., Augeri, D., Cheah, C., Ngoprasert, D., and Wai-Ming, W. (2017). Helarctos malayanus. The IUCN Red List of Threatened Species. https://doi.org/10.2305/IUCN.UK.2017-3.RLTS.T9760A45033547.en
Fredriksson, G. M., Wich, S. A., and Trisno (2006). Frugivory in sun bears (Helarctos malayanus) is linked to El Nino-related fluctuations in fruiting phenology, East Kalimantan, Indonesia. Biological Journal of the Linnean Society, 89(3), 489-508. https://doi.org/10.1111/j.1095-8312.2006.00688.x
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Linkie, M., Guillera-Arroita, G., Smith, J., Ario, A., Bertagnolio, G., Cheong, F., et al. (2013). Cryptic mammals caught on camera: Assessing the utility of range wide camera trap data for conserving the endangered Asian tapir. Biological Conservation, 162, 107-115. https://doi.org/10.1016/j.biocon.2013.03.028
Te Wong, S., Servheen, C., Ambu, L., and Norhayati, A. (2005). Impacts of fruit production cycles on Malayan sun bears and bearded pigs in lowland tropical forest of Sabah, Malaysian Borneo. Journal of Tropical Ecology, 21(6), 627-639. https://doi.org/10.1017/S0266467405002622
Crudge, B., O'Connor, D., Hunt, M., Davis, E. O., and Browne-Nunez, C. (2018). Groundwork for effective conservation education: an example of in situ and ex situ collaboration in South East Asia. International Zoo Yearbook, 52(1), 167-175. https://doi.org/10.1111/izy.12181

Where Do Sun Bears Live? Tropical Forests Across 11 Southeast Asian Countries