Helarctos malayanussun bear

Geographic Range

Helarctos malayanus ranges from the eastern Himalayas to Szechuan in China, then southward throughout Burma, parts of Indochina and the Malayan peninsula. Their range is probably greater than what is actually known. (Sanderson, 1972; Ward and Kynaston, 1995)

Habitat

Sun bears are found in dense lowland tropical forests. They can commonly be found climbing in trees. (Sanderson, 1972)

Physical Description

Sun bears are the smallest bears in the family Ursidae. They stand 70 cm at the shoulder and are 1.2 to 1.5 m from head to tail. The tail itself is 3 to 7 cm. Males are larger than the females but only by 10 to 20%. They have short, wide, flat heads with small round ears. Their fur is rather coarse but appears sleek. This coat is entirely black except for a "U" shaped patch on the chest and a grey to faintly orange muzzle. The yellowish or white chest patch is highly variable, "U" shaped in some and completely absent in others. This mark may exaggerate bears' sizes during fights. The young are born with soft, shiny coats. The paws are fairly large with sickle-shaped claws and naked soles which are thought to be helpful in climbing trees. These bears have an interesting walk, with all four legs turned in while walking. (International Association for Bear Research and Management (IBA), 1999; Nowak, 1997; Sanderson, 1972; Ward and Kynaston, 1995)

  • Sexual Dimorphism
  • male larger
  • Range mass
    27 to 65 kg
    59.47 to 143.17 lb
  • Range length
    1.2 to 1.5 m
    3.94 to 4.92 ft

Reproduction

Little is known about mating in sun bears.

Little is known about the reproductive behavior of sun bears in the wild. Gestation period lasts about 95 days, but there is evidence of delayed implantation. Some sun bear pregnancies in a zoo in Fort Worth lasted 174 to 240 days. A sun bear at the Berlin Zoo actually gave birth two times in one year in 1961, first in April, then again in August, but this is rare. Litter size is usually around one to two but occasionally there are three. Newborns are blind, hairless, and helpless and weigh a mere 300 grams. Cubs stay with their mothers until fully grown and reach sexual maturity around three years of age. (International Association for Bear Research and Management (IBA), 1999)

  • Breeding interval
    Frequency of breeding in females is unknown.
  • Breeding season
    Breeding occurs throughout the year.
  • Range number of offspring
    1 to 3
  • Average number of offspring
    1-2
  • Average number of offspring
    1
    AnAge
  • Range gestation period
    95 to 240 days
  • Average age at sexual or reproductive maturity (female)
    3 years
  • Average age at sexual or reproductive maturity (female)
    Sex: female
    2372 days
    AnAge
  • Average age at sexual or reproductive maturity (male)
    3 years

Like other bear species, sun bear females invest large amounts of energy into raising their altricial young to a stage at which they are able to be independent.

  • Parental Investment
  • altricial
  • pre-fertilization
    • provisioning
    • protecting
      • female
  • pre-hatching/birth
    • provisioning
      • female
    • protecting
      • female
  • pre-weaning/fledging
    • provisioning
      • female
    • protecting
      • female
  • pre-independence
    • provisioning
      • female
    • protecting
      • female
  • extended period of juvenile learning

Lifespan/Longevity

In captivity sun bears have lived up to 24 years and nine months. (Helin, 1999)

  • Range lifespan
    Status: captivity
    24.75 (high) years
  • Average lifespan
    Status: captivity
    35.9 years
    AnAge

Behavior

Sun bears are active at night and are excellent and agile climbers. They sleep and sun bath in trees at heights from 2 to 7 m. This species does not go through periods of hibernation, probably because they live in tropical areas and their food sources are present year round. (Nowak, 1997; Sanderson, 1972)

Communication and Perception

Like other bear species, sun bears have a keen sense of smell. Bears tend to use their senses of smell and touch to find and manipulate food. They probably use olfactory cues to find potential mates and use some vocalizations. (Nowak, 1997)

Food Habits

Sun bears are opportunistic omnivores, with bees, termites, and earthworms comprising the main part of their diet. Fruit is also eaten when available. The former are more regular food sources than fruit and usually there is no need for H. malayanus to cover great distances in their search for food. These bears have long tongues that are helpful for obtaining insects from trees, termites from their nests, and honey from bee hives. Should the opportunity present itself, sun bears will eat small rodents, birds, and lizards along with scavenging tiger kills. In human populated areas their diet may include rubbish, livestock, and agricultural fruit such as bananas. (Ward and Kynaston, 1995)

  • Animal Foods
  • birds
  • mammals
  • carrion
  • insects
  • terrestrial worms
  • Plant Foods
  • fruit

Predation

Predation on sun bears is not reported. Because of their size they are likely to have few natural predators. Young bears may be killed by aggressive conspecifics or by tigers.

  • Anti-predator Adaptations
  • cryptic

Ecosystem Roles

In certain regions, sun bears are important in seed dispersal. In a study of H. malayanus in Borneo, one sample of these bear feces was found to contain 309 seeds of a certain species of plant. They also impact the colonial insect populations that they prey on. (McConkey and Galetti, 1999)

  • Ecosystem Impact
  • disperses seeds

Economic Importance for Humans: Positive

The gall bladders and other body parts of sun bears are used in folk medical practices. It has been proven, though, that they have no medicinal value. People hunt them for sport and profit. They are commonly sold as pets when they are cubs, but quickly outgrow the stage when they are manageable as pets. (Sanderson, 1972)

Economic Importance for Humans: Negative

Sun bears have been known to cause damage to crops such as oil palms, coconuts, and bananas.

  • Negative Impacts
  • crop pest

Conservation Status

Sun bears are one of the rarest bears. The exact number alive today is not known, but the population is steadily declining due to deforestation and hunting. Habitat destruction is causing these bears to live in smaller and more isolated patches. The land is being cleared to create coffee, rubber and oil palm plantations. Poachers are flocking to protected areas and reserves because they know there are bears there. Reserves may not even be providing sufficient habitats for these bears because their needs are not completely known. Not many conservation attempts have been done to save these bears because so little is known about them. (Servheen Christopher, March/April 1999; Ward and Kynaston, 1995)

Other Comments

One sun bear demonstrated his intelligence while in captivity. This particular bear took the rice that was given to him for food and scattered it on the ground. There were also chickens in this bear's lair and the scattered rice attracted these chickens, which the bear then captured and ate. (Nowak, 1997)

Contributors

Tanya Dewey (editor), Animal Diversity Web.

LeeAnn Bies (author), University of Michigan-Ann Arbor, Cynthia Sims Parr (editor), University of Michigan-Ann Arbor.

Glossary

acoustic

uses sound to communicate

altricial

young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching. In birds, naked and helpless after hatching.

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

carrion

flesh of dead animals.

chemical

uses smells or other chemicals to communicate

cryptic

having markings, coloration, shapes, or other features that cause an animal to be camouflaged in its natural environment; being difficult to see or otherwise detect.

delayed implantation

in mammals, a condition in which a fertilized egg reaches the uterus but delays its implantation in the uterine lining, sometimes for several months.

drug

a substance used for the diagnosis, cure, mitigation, treatment, or prevention of disease

endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

forest

forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

nocturnal

active during the night

omnivore

an animal that mainly eats all kinds of things, including plants and animals

oriental

found in the oriental region of the world. In other words, India and southeast Asia.

World Map

pet trade

the business of buying and selling animals for people to keep in their homes as pets.

rainforest

rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Epiphytes and climbing plants are also abundant. Precipitation is typically not limiting, but may be somewhat seasonal.

sedentary

remains in the same area

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

solitary

lives alone

tactile

uses touch to communicate

terrestrial

Living on the ground.

tropical

the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.

visual

uses sight to communicate

viviparous

reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.

year-round breeding

breeding takes place throughout the year

References

Helin, S. 1999. Mammalian of China. Beijing, China: China Forestry Publishing House.

International Association for Bear Research and Management (IBA), 1999. "Sun Bear" (On-line). Accessed Nov. 27, 2001 at http://www.bearbiology.com/sudesc.html.

McConkey, K., M. Galetti. 1999. Seed dispersal by sun bear *Helarctos malayanus* in Central Borneo. Tropical Ecology, 15: 237-241.

Nowak, R. 1997. ""Walker's Mammals of the World"" (On-line). Accessed Nov. 1, 2001 at http://www.press.jhu.edu/books/walkers_mammals_of_the_world/special.html.

Sanderson, I. 1972. Living Mammals of the World. Garden City, New York: Doubleday and Company.

Servheen Christopher, March/April 1999. "Bear COnservation Around the World" (On-line). Accessed Nov. 27, 2001 at http://www.fonz.org/zoogoer/zg1999/28%282%29bearconserve.htm.

Ward, P., S. Kynaston. 1995. Bears of the World. London: Blanford.