Sun Bear

The sun bear is the smallest bear species, found in tropical forests of Southeast Asia from northeast India through mainland Southeast Asia to Brunei and Indonesia. It weighs 25-65 kg and stands nearly 70 cm at the shoulder, with short, jet-black fur and an orange to cream chest patch that gives it its name. It is the most arboreal of all bears and an excellent climber, sunbathing or sleeping in trees 2 to 7 m above the ground. An omnivore, it eats ants, bees, beetles, honey, termites, seeds and fruit, extracting insects and honey with an exceptionally long tongue. It does not hibernate.

About the sun bear

The sun bear is the smallest bear species and the only member of the genus Helarctos. It lives in the tropical forests of Southeast Asia, from northeastern India to Borneo, and is named for the orange to cream crescent on its chest. It is the most tree-dwelling of all bears.

Helarctos malayanus was first described from Sumatra in 1821, and its genus name combines the Greek words for "sun" and "bear." It is also called the honey bear, a nod to its love of raiding bees' nests. Its closest relatives have been debated: sun bears and sloth bears can produce fertile hybrids, and genetic studies suggest those two species were the first branches of their subfamily, outside the Ursus group, which includes the two black bears, such as the American black bear.

The sun bear stands nearly 70 cm (28 in) at the shoulder, with a head-and-body length of 100 to 140 cm (39–55 in). Adults weigh 25 to 65 kg (55–143 lb), and males are roughly 10 to 20% larger than females. The build is stocky, with large paws, strongly curved claws, small rounded ears and a short snout.

Its coat is the shortest of any bear, a fit for a hot climate. The fur is usually jet black but can range from gray to red, and the snout is gray, silver or orange. The chest patch is typically U-shaped, though it can be round or spotted, and it varies from orange or ochre-yellow to buff, cream or even white. A few sun bears have no patch at all. Cubs are grayish-black with a pale snout and a dirty-white chest mark.

The head is large and heavy for the body, with very large teeth, especially the canines. Its bite is unusually strong for its size: a 50 kg (110 lb) sun bear can bite with a force of about 1,900 to 2,000 newtons at the back teeth. That power may help it tear into tropical hardwood trees for insects and honey. It also has an exceptionally long tongue for licking insects and honey out of crevices.

Behavior and diet

The sun bear is built for climbing. Inward-turned front feet, a flattened chest, powerful forelimbs and big claws make it an excellent climber, and it spends more time in trees than any other bear. It sunbathes or sleeps 2 to 7 m (6.5–23 ft) above the ground. Most resting spots are hollow fallen logs, but it also uses tree cavities, spaces under logs and roots, and high branches. It is a capable swimmer too.

Sun bears are mostly diurnal, though they may be more active at night where people are around. They live alone, except for mothers with cubs. They do not hibernate, probably because food is available all year in the tropics.

When it wants a better view or a better scent, a sun bear stands on its hind legs. If threatened, it rears up and shows off its chest patch to intimidate the enemy. It grunts and snuffles while foraging, gives short barks when surprised, and during the breeding season can roar. Sun bears are also known for intelligence: one captive bear watched sugar being locked in a cupboard and later opened the lock with its claw. A 2019 study found that sun bears can mimic each other's facial expressions with precision comparable to gorillas and humans.

The diet is broad. Sun bears eat ants, bees, beetles, termites and honey, along with seeds and many kinds of fruit, including figs. They rip open hollow trees with their claws and teeth to reach wild bees and honey, and they break apart termite mounds, holding the pieces in their front paws while licking and sucking out the insects. They also eat the heart of coconut palms and crush oil-rich seeds such as acorns. Reptiles, birds, deer and even forest tortoises are eaten occasionally. When fruit is scarce, they shift to eating more insects. In Central Borneo, sun bears play an important role in dispersing the seeds of the tree Canarium pilosum.

Home ranges cover roughly 7 to 27 sq km (2.7–10.4 sq mi). The tiger is the sun bear's main predator, while dholes and leopards occasionally kill them. In one recorded case, a large reticulated python swallowed a wild female sun bear.

Sun bears breed year-round. Sun bears become sexually mature at two to four years of age, and reported pregnancy lengths range from 95 to 240 days. Cubs are born in hollow trees, one or two at a time, weighing about 325 g (11.5 oz). They are born deaf with closed eyes, and they cannot see until about 50 days old. Mothers guard their cubs fiercely, and the young stay with them for nearly three years.

Range and habitat

The sun bear lives in the tropical forests of Southeast Asia. Its range reaches from northeastern India in the north through Bangladesh, Myanmar, Thailand, Cambodia, Laos and Vietnam, and south to Malaysia, Brunei and Indonesia. A sighting in Yunnan Province in 2017 confirmed it in China. It has disappeared from Singapore.

Two main forest types support it: seasonal deciduous and evergreen forests north of the Isthmus of Kra, and non-seasonal evergreen rainforest in Malaysia and Indonesia. It is usually found at low elevations, for example below 1,200 m (3,900 ft) in western Thailand and peninsular Malaysia, but in India more sun bears have been recorded at up to 3,000 m (9,800 ft), probably because lowland habitat has been lost.

Sun bears tend to avoid heavily logged forest and areas near people. Even so, they sometimes enter farms, plantations and orchards, where they may be treated as pests. Populations appear to get smaller moving north, and numbers are especially low at the northern and western edges of the range.

Conservation status

The sun bear is listed as Vulnerable on the IUCN Red List, in a 2017 assessment. The global population is estimated to have fallen by about 35% since the 1990s, and populations are declining in most countries where it lives. It is already locally extinct across much of its former range, especially in Thailand.

The biggest threats are heavy deforestation from farming, logging and fires, and hunting for the wildlife trade. Southeast Asia lost almost 12% of its forest cover between 1990 and 2010. Sun bears are poached for meat, kept as pets, and killed for body parts such as gall bladders sold in traditional medicine. They are also kept on bear bile farms in Laos, Vietnam and Myanmar. Farmers sometimes shoot or poison them to protect coconut and snakefruit crops.

The sun bear is listed on Appendix I of CITES and is legally protected from hunting across its range except in Sarawak and Cambodia, though enforcement is often weak. The sun bear has been managed under a captive-breeding Species Survival Plan since late 1994, and several sanctuaries in Southeast Asia care for rescued bears and work against illegal trade.