The sun bear ( Helarctos malayanus) is a bear species in the family Ursidae found in the of Southeast Asia. It is the only species in the genus Helarctos and the smallest bear species, standing nearly at the shoulder and weighing . It is stockily built, with large paws, strongly curved claws, small, rounded ears and a short snout. The fur is generally short and jet black, but can vary from grey to red. The sun bear gets its name from its characteristic orange to cream-coloured chest patch.
The sun bear's unique morphology with inward-turned front feet, flattened chest, powerful forelimbs with large claws suggests adaptations for climbing, and it is an excellent climber and the most Arboreality of all bears. It sunbathes or sleeps in trees above the ground. It is mainly active during the day, though nocturnality might be more common in areas frequented by humans. It tends to remain solitary, but sometimes occur in pairs such as a mother and her cub. It does not hibernation, possibly because food resources are available the whole year throughout its range. It is an omnivore, and its diet includes ants, bees, beetles, honey, termites, and plant material such as seeds and several kinds of fruits; such as birds and deer are also eaten occasionally. It breeds throughout the year; individuals become sexually mature at two to four years of age. Litters comprise one or two cubs that remain with their mother for around three years.
The range of the sun bear is bounded by northeastern India to the north then south to southeast through Bangladesh, Cambodia, Myanmar, Laos, Thailand, and Vietnam in mainland Asia to Brunei, Indonesia, and Malaysia to the south. These bears are threatened by heavy deforestation and illegal hunting for food and the wildlife trade; they are also harmed in conflicts with humans when they enter farmlands, plantations, and orchards. The global population is estimated to have declined by 35% since the 1990s. It is listed as vulnerable on the IUCN Red List.
+ !Image !Name !Distribution !Description/Comments | |||
Malayan sun bear ( H. m. malayanus) | The Malayan sun bear occurs on the Asian mainland and Sumatra. | Smallest member of the bear family. | |
Bornean sun bear ( H. m. euryspilus) | The Bornean sun bear occurs only in Borneo. | Its skull is smaller than that of the Malayan sun bear. |
H. annamiticus, described by Pierre Marie Heude in 1901 from Annam, is not considered a distinct species, but is subordinated as a junior synonym to H. m. malayanus. In 1906, Richard Lydekker proposed another subspecies by the name H. m. wardii for a sun bear skull, noting its similarities to a skull from Tibet with a thicker coat, but the Tibetan specimen was later found to be an Asian black bear ( Ursus thibetanus). Genetic differences between the two subspecies are obscure and some authorities consider the species Monotypic taxon.
During feeding, the sun bear can extend its exceptionally long tongue to extract insects and honey. The teeth are very large, especially the Canine tooth, and the bite force quotient is high relative to its body size for reasons not well understood; a possible explanation could be its frequent opening of tropical hardwood trees with its powerful jaws and claws in pursuit of insects, larvae, or honey. The bite force is high for its size: a sun bear weighing bites with a maximum force of 1907.3–2020.6 Newtons on the rear molar. The head is large, broad and heavy in proportion to the body, but the ears are proportionately smaller; the palate is wide in proportion to the skull. The overall unique morphology of this bear, such as its inward-turned front feet, flattened chest, and powerful fore limbs with large claws, indicates adaptations for extensive climbing.
These bears dwell primarily in two main types of forests throughout their range - Deciduous forest and seasonally Evergreen forest forests to the north of the Isthmus of Kra, and non-seasonal evergreen forests in Indonesia and Malaysia. They are typically found at low altitudes, such as below in western Thailand and peninsular Malaysia, but this varies widely throughout the range; in India, larger numbers have been recorded at elevations up to than in low-lying areas, probably due to habitat loss at ground level. They occur in montane areas in northeast India, but may not extend farther north into the unfavourable and colder Himalayas region; their distribution might be restricted to the northwest due to competition with sloth bears. The sun bear is sympatric with the Asian black bear throughout the remaining areas in the mainland range featuring a mix of seasonal forest types, with monthly rainfall below for a long spell of 3–7 months. In mountainous areas, Asian black bears are more common than sun bears, probably due to scarcity of invertebrates on which to feed. The major habitats in southern Thailand and peninsular Malaysia are moist evergreen forests, with more or less unvarying climate and heavy rainfall throughout the year, and low-lying or montane dipterocarp forests. may be inhabited, but usually only when they are close to preferred habitat types.
The sun bear tends to avoid heavily logged forests and areas close to human settlement. However, sun bears have been seen in farmlands, plantations and orchards, where they may be considered vermin. A survey in Lower Kinabatangan Segama Wetlands showed that sun bears were feared but were not common in oil palm plantations; Bornean bearded pigs, elephants and were far more damaging to crops. Sun bears have been reported preying on poultry and livestock.
Fossil remains suggest its occurrence farther north during the Pleistocene; it may have occurred as far south as Java in the middle to Late Pleistocene. Fossils also known from the Middle Pleistocene of Thailand along with Stegodon, gaur, wild water buffalo, and other living and extinct mammals. Today, it is local extinction in the majority of its erstwhile range, especially in Thailand; populations are declining in most of the range countries. It disappeared from Singapore during the 1800s and 1900s, possibly due to extensive deforestation. Sun bear populations appear to decrease in size northward from Sundaland, and numbers are especially low in the northern and western extremes of the range. This has possibly been the case since prehistoric times, and is not a result of human interference. The population density varies from in Khao Yai National Park to in the Harapan Rainforest in southern Sumatra.
The sun bear is solitary but is sometimes seen in pairs such as mothers and cubs. For a broad view of its surroundings or smell far-off objects, it stands on its hind feet; it tries to intimidate its enemies by displaying its chest patch if threatened. Its vocalisations includes grunts and snuffles while foraging for insects, and roars similar to those of a male orangutan during the breeding season; less commonly, it gives out short barks when surprised. It does not hibernate, possibly because food resources are available the whole year throughout the range.
The sun bear is mainly active during the day, although nocturnality might be more common in areas frequented by humans. It is noted for its Animal cognition; a captive bear observed sugar being stored in a cupboard locked by a key, and later used its claw to open the lock. A study published in 2019 described skillful mimicry of facial expressions by sun bears, with precision comparable to that seen in and humans.
The sun bear has of varying sizes in different areas, ranging from in Borneo and Peninsular Malaysia; and in Ulu Segama Forest Reserve in Sabah.
The tiger is its major predator; and leopards have also been recorded preying on sun bears, but cases are relatively few. In one incident, a tiger-sun bear interaction resulted in a prolonged altercation and in the death of both animals. In another incident, a wild female sun bear was swallowed by a large reticulated python in East Kalimantan.
Sun bears usually do not attack humans unless provoked to do so, or if they are injured or with their cubs; their timid nature led these bears to be often Taming and kept as in the past. Sun bears are fierce when surprised in the forest.
On the island of Borneo sun bears were found to be hunted by pythons in their most vulnerable state. Pythons are successfully able to attack by taking advantage of the night time when the sun bears are sleeping or nursing their cub. In Southeast Asia, a male leopard ( Panthera pardus) has been photographed with a sun bear cub being held by the throat. This reported case has been reported to be the second confirmed predator as of 2019.
Studies have found evidence of pet trade and sale of sun bear parts such as in traditional Chinese medicine (TCM) shops in Sabah and Sarawak. In 2018 and 2019, 128 TCM outlets in 24 locations across Sabah and Sarawak were surveyed and bear parts and derivatives were recorded for sale in 25% of the outlets surveyed, many of which would have been derived from locally sourced sun bears. Sun bears were killed by shooting or administering poison to protect coconut and snakefruit plantations in east Kalimantan. A report published by TRAFFIC in 2011 showed that sun bears, along with Asian black bears and , are specifically targeted for the Bile bear trade in Southeast Asia, and are kept in bear farms in Laos, Vietnam, and Myanmar. Poaching is common in several countries in the region.
Hunting pressure is rising even in some protected areas; in the Nam Ha National Protected Area in Laos, hunter snares have been found that specifically target bears. A study in Nagaland (northeastern India) recorded a sparse distribution of sun bears in Fakim and Ntangki National Parks, and reported extensive illegal hunting for food and trade in bear parts. Protective laws have shown little success in controlling these threats, especially due to poor execution and high potential for gains by the trade.
The Bornean Sun Bear Conservation Centre, founded by Wong Siew Te in Sabah (Malaysia) in 2008, aims to work for the welfare of sun bears rescued from poor conditions in captivity and spread awareness about their conservation. The Malayan sun bears are part of an international captive-breeding program and a species survival plan under the Association of Zoos and Aquariums since late 1994. Since that same year, the European breed registry for sun bears is kept in the Cologne Zoological Garden, Germany.
Phylogeny
Characteristics
Distribution and habitat
Ecology and behaviour
Diet
Reproduction
Threats
Conservation measures
External links
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