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Sloth Bear


Order: Carnivora
Genus & Species: Melursus ursinus
Family: Ursidae


Listed as Vulnerable by IUCN, due to fragmented populations, competition with other animals (particularly humans) for space and food, deforestation, and the bear parts trade for use in traditional Asian medicines. Natural predators such as wild dogs, tigers, and leopards also take a toll on juveniles. Less than 10,000 remain in the wild.


Most are found in India & Sri Lanka. They have also been reported in lower elevations of Bangladesh, Nepal, and Bhutan.


Prefers grasslands and forested areas at predominantly lower altitudes. It is more often found in drier forests and areas with rock outcroppings.


Sloth bears prefer to forage at night, in a solitary fashion, when temperatures are cooler. However, females with cubs may forage during the day, so as not to compete with other bears or nocturnal predators for resources.


In the wild is 20 – 25 years; up to 40 years in captivity


In the wild: omnivorous.  Their diet depends greatly on the local habitat and season. Diet can consist of termites or other insects, grubs, cultivated crops, grass, honey, eggs, carrion, fruits, berries, and flowers.

At the zoo: Omnivore chow, insects, honey, browse, eggs, a wide variety of fruits and vegetables.


These animals were initially classified as bear sloths, due to their slow gait and ability to climb trees. Not until 1810 did the classification change; for sake of simplicity, the name was switched to sloth bear.

Sloth bears are stocky with long, shaggy, black hair and a white U- or Y-shaped marking on the chest. They have large lips, a long tongue, a pale muzzle and well-developed hook-like claws that enable them to climb trees and dig for termites.

Females and males do not differ greatly in height or length, they are up to 6.25 feet (1.9 m) long, and up to 36 inches (92 cm) tall; Adult male: 200-320 pounds (91-145 kg)   Adult female: 121-210 pounds (55-95kg)


Reproduction:  Sloth bears reach sexual maturity at about 3 to 4 years of age. When mating, sloth bears are loud, and often engage in hugging or mock fighting. Mating usually occurs April – June.  Gestation is 180-210 days in captivity. Like some bears, sloth bears can delay implantation of the fertilized embryo if the food supply is scarce. One to three cubs are born in the dry season, usually in December or early January. Birth occurs in a den, cave, or a shelter beneath boulders. Average birth weight is 10.5-17.5 ounces (300-500 g).

Parental care:  Although newborn cubs have strong toes and forelegs, they are extremely tiny and blind at birth. Their eyes open in about three weeks, and they can walk at four weeks. Rapid growth occurs, mostly in the legs. Young receive nourishment from their protein-rich mother’s milk for up to three years, but start to sample other foods when 2 to 3 months old. Cubs stay with their mother until they are independent and can care for themselves, at 2 or more years of age. Hence, females have breeding intervals of 2 or 3 years.

Ecology, Adaptations, Etc:

Perhaps another reason that sloth bears were thought to be sloths was their massive consumption of insects, especially termites. Because termite and ant colonies are an abundant and consistent source of food for sloth bears, they are the only bear specifically adapted for feeding on insects. Sloth bears dig out insect mounds with their sharp, 3-inch (7.6 cm) long claws. Then, they blow away the dirt and debris with their long, mobile lips. Finally, with a huge breath, the sloth bear sucks out the termites. Since sloth bears lack their two front incisors and have a hollowed palate, they can quickly remove the insects like a high-powered vacuum. Sloth bears also love honey, and they will easily climb up to 26 feet (8 m) into the trees or hang from branches to raid honeycombs.

Sloth bears are solitary except when raising young or mating. The bears have a number of vocalizations, but their purpose is not understood.

Sloth bears have an excellent sense of smell, good vision and satisfactory hearing. Reliance on their sense of smell, rather than sight or hearing, can lead to confrontation between humans and sloth bears. Often, the shy sloth bear’s reaction to being startled is to attack savagely with a charge.

Fun Facts:

Unlike other species, a sloth bear mother will carry the cubs on her back! Sloth bears are known to suck their front paws while sleeping. Sloth bears do not hibernate, due to the climate and environment.