Sun Bear

The sun bear is named so for its characteristic orange- to cream-coloured, crescent-like chest patch. It is the smallest of all bear species. It is stockily built, with large paws, strongly curved claws, small rounded ears and a short snout. The head-and-body length is between 100 and 140 cm (39 and 55 in), and the shoulder height is nearly 70 cm (28 in). Males tend to be larger than females by roughly 10-20%. Adults weigh 25–65 kg (55–143 lb). The snout is grey, silver, or orange. The fur is generally jet black, but can vary from grey to red. The hair is silky and fine, and is the shortest of all bear species, suiting its hot tropical habitat. The characteristic chest patch, typically U-shaped, but sometimes circular or spotlike, varies from orange or ochre-yellow to buff or cream, or even white. Some individuals lack this patch. Sun bears can expose the patch while standing on their hind feet as a threat display against enemies. Infants are greyish black with a pale brown or white snout and the chest patch is dirty white; the coat of older juveniles may be dark brown. The underfur is particularly thick and black in adults, while the guard hairs are lighter. Two whorls occur on the shoulders, from whence the hair radiates in all directions. It has a crest on the sides of the neck and a whorl in the centre of the breast patch. …

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 consider the species monotypic.

The sun bear leads a particularly arboreal lifestyle among bears. It is a capable climber; it sunbathes or sleeps in trees 2 to 7 m (6 ft 7 in to 23 ft 0 in) above the ground. Bedding sites consist mainly of fallen hollow logs, but they also rest in standing trees with cavities, underneath fallen logs or tree roots, and in tree branches high above the ground. It is also an efficient swimmer. 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 intelligence; a captive bear observed sugar being stored in a cupboard locked by a key, and later used its claw to open the lock. …

The generic name Helarctos comes from two Greek words: ήλιος (hēlios, related to the sun) and αρκτος (arctos, bear). Another name is "honey bear", beruang madu in Malay and Indonesian, in reference to its habit of feeding on honey from honeycombs.