sun bear

Southeast Asia and East Asia are home to three bear species: 1) the sloth bear of the Indian subcontinent; 2) sun bears (also known as Malayan bears) of southern Asia; and 3) moon bears (also known as Asiatic black bears) bears of Asia. Relatively little is known about these bears. There are also brown bears in the Himalayas, northern China, Mongolia, Japan and Russia but I will cover them later in articles on Northern Asian Animals. [Sources: Wikipedia, Bears of the World by Terry Domico and Mark Newman (Facts on File, 1988) and articles from National Geographic, Smithsonian magazine and the New York Times]

Sun Bears

The sun bear, also known as the honey bear, is he only truly tropical bear. Relatively small and elusive, it is found primarily in the lowland tropical rainforests in Southeast Asia, northeast India, Bangladesh, southern China and the islands of Sumatra and Borneo. The largest population of them is thought to be in Borneo. The sun bear is named after the reddish “sun” patch on its chest that varies in shape from a U-shape to a circle to an irregularly-shaped spot---and sometimes is not present at all. Its stocky, doglike body and small size have earned it the ocla name dog bear.

The sun bear is mainly nocturnal and little is known about it. It spends much of its time in trees and sometimes rests or even sleeps on rough nests made of bent-over broken branches. On the Sabah-Sarawak border of Borneo, sun bears have been reported living at 2,300 meters. The fact that so few bears are found even in relatively undisturbed rain forests has led scientists to surmise they need very large territories to survive.

Adult sun bears have few predators except humans, due to their fierce reputation and formidable teeth. Occasionally, they may be overwhelmed by tigers, or large reticulated pythons. Other possible predators include the leopard, the clouded leopard, and the sun bear's larger relative, the Asiatic black bear. The bear's loose skin on its neck allows it to wriggle its body inside its skin far enough to turn around and bite its attacker when grabbed. It addition to biting it can rip at attackers with its sharp claws. Some locals say a sun bear is the most dangerous animal a person can encounter in the forest and even tigers keep their distance. There have been reports of unprovoked attacks on other animals, with the sun bear barking as it attacks.

Sun bears are very hard to find in the wild and precious little is known. The recent decline in the sun bear population can be largely attributed to the hunting of "nuisance bears" that destroy crops and widespread poaching driven by the market for their fur and for their bile, which is used in Chinese medicine. Sometimes mothers are shot by poacher for their body parts and the cubs are sold as pets. Because it spends so much time in trees, the sun bear can sometimes cause damage to property. It has been known to destroy coconut palms and cacao trees on plantations. They like palm hearts---whose removal can kill a tree--- and sometimes return to same place on successive night, inflicting heavy damage. The biggest threat to the sun bear is habitat destruction as a result of deforestation caused by slash-and-burn agriculture, logging and rubber and palm oil plantation development.

Sometimes, sun bears are captured or bred to be domestic pets---a role for which they are considered desirable, due to their relatively inoffensive nature and small size in comparison with other bears. Cubs are very playful and adorable. Poachers in Borneo use logging roads to gain access remote tracts of forest and scan the forest with searchlights---an illegal technique in the U.S. called “jacklighting”---to locate bears and other animals by the bright glow of their eyes and stun them long enough to blast them out of the trees with a shotgun. The IUCN classified the sun bear as "vulnerable" in 2007.

Sun Bear Characteristics

The sun bear is 120 to 150 centimeters (47 to 60 inches) long and stands 60 to 78 centimeters (24 to 28 inches) at the shoulder, making it the smallest member in the bear family. It tail is 1.2 to 2.8 inches (3 to 7 centimeters ) long. Males tend to be 10 to 45 percent larger than females. Males normally weigh between 30 and 70 kilograms (66 and 154 pounds) and females between 20 and 40 kilograms (44 and 88 pounds). A bear that is over 50 kilograms is considered big.

The sun bear possesses very long sickle-shaped claws that are relatively light in weight. These claws and large paws with naked soles are adaptions for tree climbing. Its inward-turned feet make the bear's walk pigeon toed, but also assist it in climbing which it does by hugging the tree with its front limbs and ahuling itself up with its teeth. The claws are also used to dig for worms and insects, to tear ip barck and old logs to get at termites and remove honey from bee’s nests.

It has small, round ears and a stout snout. The sun bear possesses a very long, slender tongue, ranging from 8 to 10 inches (20 to 25 cm) in length. The bear uses it to extract honey from beehives and gather grubs from deep inside holes. Loose skin around its neck allows it to turn and fight even if a predator such as a tiger seizes it by the neck.

Unlike other bears, the sun bear's fur is short, desne and sleek. This adaptation is probably due to the lowland climates it inhabits. The dense fur which you think might be a handicap in dense forests is actually quite good at shedding rain and mud. Dark black or brown-black fur covers its body, except on the chest, where there is a pale orange-yellow marking in the shape of a horseshoe. Similar colored fur can be found around the muzzle and the eyes. These distinctive markings give the sun bear its name.

Sun Bear Feeding

The diet of the sun bear consists mainly of invertebrates and fruits but as omnivores they will eat a wide variety of foods including small vertebrates, such as lizards, birds, and turtles, eggs, the young tips of palm trees, nests of bees, grubs, berries, sprouts, roots, and coconuts. In fact, sun bears have been observed to eat over 100 insect species and over 50 plant species. Sometimes it feeds on termites by placing its front paws alternately in a termite nest, licking off the insects with it long tongue when they crawl on his claws.

Despite being able to eat many leaves, the sun bear has certain favourite food sources. This was demonstrated in a study where termites, ants, beetles and beetle larvae made up the majority of the invertebrates eaten, whilst figs were the most important fruit source consumed. They eat termites by thrusting their paws into termite mounds and licking them off their paws. Fruit is picke in the trees. Fallen fruit is collected on the ground, The sun bear's fondness for honey gives rise to its alternative name of the 'honey bear'. In Malay and Indonesian, it is known as 'Beruang Madu' which translates to honey bear.

The sub bear’s powerful jaws can crack open nuts. Its long, powerful claws are used to break into tree trunks and fallen logs to access honey, grubs and termites. Much of the sun bear's food must be detected using its keen sense of smell, as its sight is poor. Because food supplies in rains forest are scattered and rot quickly bears often have to cover a lot of ground and move quickly doing so to locate food.

Sun Bear Behavior and Mating

sun bear range

While studies of Sun Bears in the wild indicate they live solitary existence, most likely due to competition for food, in captivity they exhibit social behavior. Being a primarily nocturnal creature, the sun bear tends to rest during the day on lower limbs not far above the ground. They sometimes make nests that resemble those made by orangutans but are closer to a tree’s trunk. Sun bears sometimes travel in pairs and often leave scratch marks on trees, presumably to mark their territory or declare their presence in an area.

The sun bear does not hibernate, and, as a result, it can reproduce year-round. The offspring reach sexual maturity after three to four years and may live up to 30 years in captivity. A female sun bear can produce one or two cubs per per pregnancy. Sun bears undergo a roughly 96 day gestation period after which the 300 to 400 gram cub is born blind and hairless with nearly transparent skin. The cub is initially totally dependent on its mother and suckling can continue for about 18 months. After one to three months, the young cub can run, play and forage near its mother.

Females mate at about once every three years any time of the year. Courtship lasts two days to a week, during which time sun bears display behaviors like hugging, mock fighting, head bobbing and even kissing. There is some suggestion that sun bears might be monogamous. There have been sightings of sun bear couples with young. Captive male sun bears have been observed placing their paws over their heads, in a human-like frustration pose, after losing battle with their “bossy” wives, who sometimes steal their food. Cubs like to to suck their paws, often making a “humming” nose when they do so. Adult sometimes make loud roars and grunts.

Moon Bears

Asiatic black bears are sometimes called moons bears after the crescent shape white mark on the otherwise black bear has on its neck. This animal is widely distributed throughout the mountains and forests of Asia from Iran and Pakistan in the west to Japan in the east and Russia to the north and the Himalayan foothills to south. Further south in the rain forests of Southeast Asia the sun bear makes its home. Moon bears are relatively plentiful in some places but overall are threatened by overhunting and loss of habitat. There are an adaptable species found in coastal and at elevations of over 4000 meters. Between 16,000 and 25,000 of them live in high-altitude forests in Asia. They are a protected species.

The moon bear’s scientific name Selanarctos thibetanus literally means “moon bear of Tibet.” Also called the Tibetan black bear or Himalayan black bear, the animal is morphologically very similar to some prehistoric bears, and regarded by some scientists as the ancestor of all other existing bear species. Though largely herbivorous, Asian black bears can be very aggressive toward humans, and have frequently attacked people without provocation. The species was described by Rudyard Kipling as "the most bizarre of the ursine species."

Scientists have proposed that Asian black bears are a surviving, slightly-modified form of Ursus minimus, an extinct species that arose four million years ago. With the exception of the age of the bones, it is often difficult to distinguish the remains of Ursus minimus with those of modern Asian black bears. Asian black bears are close relatives to American black bears, with which they share a European common ancestor; the two species are thought to have diverged 3 million years ago, though genetic evidence is inconclusive. The earliest American black bear fossils greatly resemble the Asiatic species. One DNA study could not statistically resolve the branching order of sloth bears and the two black species, suggesting that sloth bears, moon bears and American black bears underwent a rapid radiation event.

Moon Bear Characteristics

Asian black bears are similar in general appearance to brown bears, but are more lightly built and are more slender limbed. On average they are slightly smaller than American black bears, though large males can exceed the size of several other bear species. Male moon bears grow to around twice the size of females, however, females can often be dominant and can usually be distinguished by the thicker ruff of fur around their necks.

Asian black bears measure 70 to 100 centimeters (28 to 40 inches) at the shoulder, and 120 to 195 centimeters (47 to 77 inches) in length. The tail is 11 centimeters (4.4 inches) long. Mature males typically weigh between 91 to 150 kilograms (200 to 330 pounds), with an average weight of about 113 kilograms (about 250 pounds). Females weigh about 65 to 90 kilograms (143 to 198 pounds), with large ones up to 140 kilograms (308 pounds). The largest Asian black bear on record weighed 200 kilograms (440 pounds). Zoo-kept specimens can weigh up to 225 kilograms (500 pounds). When balanced on their hind legs moon stand 1.5 to two meters tall.

Although their senses are more acute than those of brown bears, their eyesight is poor, and their powers of hearing moderate, the upper limit being 30 kHz. The skulls of Asian black bears are relatively small, but are thick, particularly in the lower jaw. Compared to other bears, moon bears have relatively flat faces (the projections of the skull are weakly developed). Although mostly herbivorous, the jaw structure of Asian black bears is not as specialised for plant eating as that of pandas.

Moon bears have thick, shaggy fur, ranging in colour from ebony black to a lighter brown-black. Their fur is quite thick around the neck and shoulders, giving them a manelike ruff. Moon bears living in warm areas such as northeast India have shorter, thinner coats. For a long time it was thought there were many Asiatic black bear subspecies but now it there is some debate as whether these are true subspecies or just different geographical races.

Moon bears have rounded heads, big round ears and short, strong claws which enable them to climb with ease. Moon bears are the most bipedal of bears. They have been observed walking almost half a kilometer upright. They usually live for 25 to 30 years in the wild. The oldest Asian black bear in captivity died at the age of 44.

Moon Bear Behavior

Asian black bear range

Moon bears tend to be solitary and diurnal, and are most active at dawn and dusk animals once they reach adulthood. They love to make dens in tree hollows, old logs and caves and often sleep there during the day or up in a tree. In some places moon bears build “basking couches,” elevated, oval-shaped beds made of twigs and branches that are thought be constructed to get the bears off the ground when the weather is cold or rainy. Some of these have been seen 20 meters off the ground.

Some Asiatic black bears hibernate. Pregnant females always hibernate. In the southern part of their range most Asiatic black bears don’t hibernate. Some migrate to lower elevations to find food. On the northern side of their range hibernation is well established. Hollows in logs and trees are preferred denning sites. In Japan the bears almost always choose sites where deep snow covers the den. In Tokyo, the Ueno Zoo was able to artificially induce an Asiatic black bear to hibernate helping the animal create a denn with a bed of straw and lowering the temperature in its pen to replicate the conditions in the mountains of northern Japan where the bear is from.

Home territories are estimated to be between six and 14 square kilometers. But, with sufficient food, Asian black bears can remain in an area of roughly one to two square kilometers, and sometimes even as little as a half to one square kilometer. Moon bears may migrate and spend the warmer months of the year at higher altitudes and then descend to the lowlands during colder months.

Asian black bears may live in family groups consisting of two adults and two successive litters of young. They will walk in a procession of largest to smallest. They are good climbers of rocks and trees, and will climb to feed, rest, sun, elude enemies and hibernate although some older bears may become too heavy to climb. Many moon bears spend half their lives or more in trees and they are one of the largest arboreal mammals. Some break branches and twigs to place under themselves when feeding on trees, thus causing many trees in their home ranges to have nest-like structures on their tops.

Moon bears are highly intelligent and make a large variety of vocalisations, including grunts, whines, roars, slurping sounds (sometimes made when feeding) and "an appalling row" when wounded, alarmed or angry. They make clucking sounds during play and courting, "tut-tut-tut" sounds when cautiously approaching other bears and huffing sounds when warning or about to attack. They issue warnings or threats by hissing, and scream when fighting. The "tut tut" sounds are thought to be produced by bears snapping their tongue against the roof of their mouth. Females are more vocal than males.

Moon Bear Feeding

Moon bears are classified as carnivores, although they follow an omnivorous diet. Their diet varies according to location and season, but predominantly consists of vegetables, fruits, nuts, acorns, honey, leaves, insects, small mammals, birds, beetle larvae, invertebrates, grubs, bees, eggs, garbage, mushrooms, grasses, seeds, herbs, cherries, dogwood, oak nuts, grain and carrion. Occasionally, moon bears may attack livestock or raid crops. There have been a number of reports of bears killing sheep, goats and cattle in Kashmir and Tibet. In Japan they sometimes damage timber trees by pealing back the bark to gnaw one sapwood underneath.

Moon bears are more herbivorous than brown bears, and more carnivorous than American black bears. They opportunistic feeders that gorge themselves on a variety of seasonal high calorie foods, storing the excess calories as fat, and then hibernate or reduce their activity during times of scarcity. Black bears will eat pine nuts and acorns of the previous year in the April to May period. In times of scarcity, they enter river valleys to gain access to hazelnuts and insect larvae in rotting logs. From mid-May through late June, they will supplement their diet with green vegetation and fruit. Through July to September, they will climb trees to eat bird cherries, pine cones, vines and grapes. On rare occasions they will eat dead fish during the spawning season, though this constitutes a much lesser portion of their diet than in brown bears. In the 1970s, black bears were reported to kill and eat Hanuman langurs in Nepal. They will kill ungulates with some regularity, including domestic livestock. Wild ungulate prey can include muntjacs, serow, takin, wild boar and adult water buffaloes, which they kill by breaking their necks.

The main natural predator of Asian black bears is the tiger, although leopards, and packs of wolves and dholes can be a threat. Eurasian lynxes are a potential predator of cubs. Black bears usually dominate Amur leopards in physical confrontations in heavily vegetated areas. The Asian black bear's range overlaps with that of sloth bears in central and southern India, sun bears in Southeast Asia and brown bears in the southern part of the Russian Far East. Russian brown bears may attack black bears, though Himalayan brown bears seem to be intimidated by them in direct encounters. They will eat the fruit dropped by black bears from trees, as they themselves are too large and cumbersome to climb.

Moon Bear Mating and Young

The moon bear breeding season is typically from mid June to mid August with births in winter or early spring after a gestation period of 200 to 240 days. Females generally have their first litter at the age of three years. Pregnant females generally make up 14 percent of populations and are capable of delayed implantation.

Pregnant females typically prepare their dens for hibernation in mid October, and sleep from November until March. Their dens can either be dug out hollow trees (often 20 meters or more above ground), caves or holes in the ground, hollow logs, or steep, mountainous and sunny slopes.

Cubs weigh 230 to 300 grams ounces at birth, and begin walking at four days of age, and open their eyes three days later. The skulls of newborn black bear cubs bear great resemblance to those of adult sun bears. Litters can consist of one to four cubs, with two being the average. Cubs have a slow growth rate, reaching only 2.5 kilograms after two months. Moon bear cubs will nurse for two years or more and become independent at two to three years. There is usually a two to three year interval period before females produce subsequent litters.

Moon Bear Characteristics and Behavior in Japan

Most Asiatic black bears weigh between 50 and 80 kilograms, with large males reaching a weight of 120 kilograms when the are fattened up at the end of autumn. Both males and females are deep black in color except for a white or cream crescent-shaped mark on their chest, which gives them the common name of “moon bear.” The size and shape of the crescent varies greatly and may even be completely absent.

Black bears have excellent hearing and sense of smell but have relatively poor eyesight. They are excellent diggers, tree climbers and swimmers. They can outrun a person on open ground and have been observed swimming 300 meters in Japan. In some places they build feeding platforms---high up in beech and oak trees and made by bending and snapping branches---that are used to feed on nuts and acorns.

Japanese black bears roam forests from sea level to the subalpine zone high on mountainsides. They are omnivores that eat nuts, fruits, insects, ants, insect grubs, river crabs, honey, leaves, acorns, other items from the forest and meat. Most of the meat they eat comes from carcasses although they have been observed hunting small deer and other animals. Their diet changes with season. In the spring and summer they load up on new shoots, buds, flowers, bulbs and tubers. In the autumn they feast on acorns, chestnuts and beechnuts as well as berries if they can find them.

Bears in Japan hibernate for around four months generally beginning in late November. When they become sufficiently fattened up they seek a cozy den in a cave, rock shelter, partially rotted log or the hollow of an old tree. While they are hibernating their body temperature drops only a few degrees and they can easily be woken up. Bears are very active in the autumn as they seek food to sustain themselves through winter hibernation. When autumn food is in short supply some bears will remain active through much of the winter. At the Ueno Zoo a bear has been artificially-induced to hibernate by replicating the conditions in the bear’s home territory.

Black bears mate in the early summer with females giving birth in their winter den. A females gives birth to one or two cubs every two or three years, a relatively slow rate of reproduction. Young bears stay close to their mothers for the first two years of their lives, gaining protection and learning skills they need to survive on their own.

Threatened Moon Bears and Humans

The Asiatic black bear is classified as “vulnerable” on the International Union of the Conservation of Nature’s Red List of endangered species. They are threatened by losses to their forest habitat and excessive hunting to gain bile and other body parts for the traditional Asian medicine trade. These are problems that bears face more elsewhere in Asia than in Japan. See China, Health, Chinese Medicine

Moon bears are the most valued bears for traditional medicine, partly because the species was so abundant in the areas where traditional medicine originated. Poaching for gall bladders and skin are the main threat faced by black bears in India. The main habitat threat to Chinese black bears is overcutting of forests, largely due to human populations encroachment, particularly in Shaanxi, Ganshu, and Sichuan provinces. They are also overhunted for black bear paws and gall bladders. Cubs have great economic value.

Vietnamese black bear populations have declined rapidly due to the pressures of human population growth and unstable settlement. South Korea remains one of two countries to allow bear bile farming to continue legally. As reported in 2009, approximately 1,374 bears reside in an estimated 74 bear farms where they are kept for slaughter to fuel the demands of traditional Asian medicine. Fewer than 20 bears can be found at Jirisan Restoration Center, located in Korea's Jirisan National Park.

In India mothers are sometimes shot and the cubs are captured and train to perform and dance by itinerant street performers and circuses. The Indian government has it has taken measures to crack down on this practice but says it doesn’t want to go too far and deprive people of their livelihood.

Although black bears have been afforded protection in Russia since 1983, illegal poaching, fuelled by a growing demand for bear parts in the Asian market, is still a major threat to the Russian population. Many workers of Chinese and Korean origin, supposedly employed in the timber industry, are actually involved in the illegal trade. Some Russian sailors reportedly purchase bear parts from local hunters to sell them to Japanese and Southeast Asian clients. Russia's rapidly growing timber industry has been a serious threat to the Asian black bear's home range for three decades. The cutting of trees containing cavities deprives black bears of their main source of dens, and forces them to den on the ground or in rocks, thus making them more vulnerable to tigers, brown bears and hunters.

Along with sun bears, Asian black bears are the most typically used species in areas where bears are either used in performances or as pets. Asian black bears have an outstanding learning ability in captivity, and are among the most common species used in circus acts. According to Gary Brown: The Asiatic black bears are the comedians of the performing bears. They appear to appreciate applause and will intentionally move into their prescribed position late to attain laughter and attention. Black bears are easily tamed, and can be fed with rice, maize, sweet potato, cassava, pumpkin, ripe fruit, animal fat and sweet foods. Keeping captive black bears is popular in China, especially due to the belief that milking the bear's gall bladder leads to quick prosperity. Bears are also popular as pets in Vietnam.

Moon Bears in Japan

There are two species of bear found in Japan: the Asiatic black bear and Ezo brown bear. Black bears are found throughout Honshu and Shikoku. Some have even been seen prowling around the streets of Kyoto. They are the same as Asiatic black bears found in China, India, Southeast Asia and Russia.

Japanese black bears are divided into seven recognized subspecies. There are healthy numbers of the main subspecies that lives mostly in mountainous areas of central and northern Honshu but the other six---in Kyushu, Shikoku, eastern and western Chugoko, the Kii Penninsual of Wakayama Prefecture, on the Himokita Peninsula in Aomori Prefecture---have been designated as endangered. The Kyushu subspecies is probably already extinct.

No one knows how many black bears there are. A study by the Environmental Ministry in 1991 estimated the number to be between 8,400 and 12,600. There are currently thought to be 10,000 to 20,000 of them, with some living a few dozen kilometers west of central Tokyo in the Kaone Mountains and Tanzawa Mountains of western Kanagawa Prefecture.

The number of black bears in western Honshu has been dramatically reduced by the prevalence of introduced cedars and cypresses, which produce no acorns for the bears to eat.

Image Sources: Wikimedia Commons

Text Sources: National Geographic, Natural History magazine, Smithsonian magazine, Wikipedia, New York Times, Washington Post, Los Angeles Times, Times of London, The Guardian, Top Secret Animal Attack Files website, The New Yorker, Time, Newsweek, Reuters, AP, AFP, The Economist, BBC, and various books and other publications.

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© 2008 Jeffrey Hays

Last updated May 2014

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