III.

Types of Bears

The bear family includes eight species, each showing remarkable variation in physical features and habits. Some scientists believe that bears and animals in the raccoon family share a common ancestor and are more closely related to each other than to other carnivores. Other scientists believe that bears are more closely related to walruses and sea lions. In the past, zoologists placed the giant panda in the raccoon family, but recent analysis of the giant panda’s genetic makeup and fossil evidence have convincingly established the giant panda as a member of the bear family.

A.

Giant Panda

Possibly the world’s best-known wild animal, the giant panda has a round body, a bullet-like head with small ears, and a short, stumpy tail. Its shaggy coat is white with a black patch around each eye and a ring of black around the shoulders, front legs, and chest. The giant panda can reach a length of 1.5 m (5 ft) and weigh 100 kg (220 lb).

The giant panda has the smallest range and smallest population of all the bears. Only about 1,600 individuals live in bamboo forests in the mountains of south-central China. Bamboo makes up about 99 percent of the giant panda’s diet, and the bear spends 12 to 14 hours each day eating up to 18 kg (40 lb) of bamboo leaves and stems or 39 kg (85 lb) of shoots. The giant panda brings food to its mouth with its front paws, using a long wrist bone that works like a thumb to grasp bamboo stems. Despite their cute, cuddly appearance, giant pandas can be provoked to aggressive defensive behavior.

With such a small population, a narrow habitat range, and a highly specialized diet, giant pandas are widely considered in great danger of extinction. They are classified as endangered species on both the United States Fish and Wildlife Service Endangered Species List and the Red List of Threatened Species compiled by the World Conservation Union (IUCN), a nongovernmental organization that compiles global information on endangered species. These classifications offer these animals protection and provide opportunities for conservation management, including strictly enforced protection from hunting in their habitats. The Chinese government, as well as many private organizations and zoos around the world, support conservation activities that encourage local people to protect the giant panda and its habitat. A number of programs sponsored by zoos or other breeding centers have attempted to breed giant pandas in captivity, although most of these programs have proved unsuccessful. Among the difficulties faced by captive breeders has been the problem of encouraging a female giant panda to mate with a selected male during the two to three days of the year when she is most fertile, a period known as estrus.

B.

Spectacled Bear

Creamy-white rings surrounding the eyes give the spectacled bear its name. Its shaggy coat of black or dark brown is marked by white or yellow coloring on the muzzle and in a roughly shaped circle on the chest. Also known as the Andean bear, it is the only bear native to South America, where it lives on the forested slopes of the Andes Mountains from western Venezuela and Colombia south to Ecuador, Peru, and Bolivia.

Spectacled bears grow to a length of about 1.8 m (about 6 ft) and weigh 62 to 154 kg (137 to 340 lb); the males are much larger than the females. Spectacled bears eat diverse foods, including small mammals and birds, grasses, fruits and berries, and parts of bromeliads (plants such as pineapple), orchid bulbs, and palm nuts. These bears build tree nests for sleeping during the day from which they can pluck fruit from nearby branches.

The IUCN Red List of Threatened Animals lists the spectacled bear as vulnerable. This status means that the bear faces a high risk of extinction in the near future, due to human encroachment on its habitat, hunting, and poaching to extract bear parts for use in folk medicine. Although the South American countries that are home to these bears have laws protecting the animal, enforcement of these laws is usually weak.

C.

Sun Bear

Named for the golden-colored crescent that adorns its chest, the sun bear is also known as the Malayan sun bear and the dog bear. A rarely seen resident of Southeast Asian rain forests, sun bears range from Burma south to the islands of Sumatra and Borneo. Sun bears grow up to 1.5 m (5 ft) long and weigh 27 to 66 kg (60 to 146 lb), making them the smallest of bears. The coat is short, sleek, and black, with light brown feet and white or orange-yellow fur on the muzzle and chest. The sun bear uses its extremely long tongue to feed on insects and honey in tree cavities. Its diet also includes fruits and vegetation, birds, and other small animals.

The sun bear is listed as vulnerable on the IUCN Red List of Threatened Animals. Scientists know little about the sun bear’s natural history, population numbers, and distribution. However, the destruction of rain forests in Southeast Asia for timber harvesting and to make room for new farmland and houses, makes the future of the sun bear seem bleak. Hunting in Thailand may have reduced its numbers in some parts of that country by 50 percent in 20 years.

D.

Sloth Bear

So called for its close resemblance to the sloths of Central and South America, the sloth bear is also occasionally referred to as the honey bear. Sloth bears inhabit forests and tall grasslands in India, Nepal, Sri Lanka, and Bhutan. Their long, shaggy coat is commonly black, but it may be red or reddish-brown, turning a lighter color on the muzzle and chest. The sloth bear grows to about 1.8 m (about 6 ft) and weighs 54 to 140 kg (119 to 310 lb). Other carnivores that share their habitat, including tigers and leopards, prey on these medium-sized bears. This may be why sloth bear mothers carry their one or two cubs on their backs—so that they can protect their young while making a quick escape from predators.

Sloth bears eat a variety of fruits, honeycombs, and insects, but with their hairless lips, flexible snout, and gapped front upper teeth these bears are particularly adapted for feeding on ants and termites. They use their long claws to open ant and termite nests. Their lips and snout then form a central opening that acts as a suction tube, which they use to suck up the insects, making sucking and blowing noises that sound like a jackhammer.

Listed as vulnerable by the IUCN Red List of Threatened Animals, sloth bears are regularly killed in order to obtain and sell bear parts, such as gallbladders, that are used in folk medicine. Laws to prevent killing of sloth bears and the export of their parts are poorly enforced, resulting in a significant harvest of the species for commercial purposes.

E.

Asiatic Black Bear

The Asiatic black bear is also known as the moon bear for the distinctive white, crescent-shaped patch on its chest. Other names for this bear include the Himalayan bear, the Tibetan bear, and the Japanese black bear. This bear lives in temperate mountain forests in widely separated areas in Asia, ranging from Afghanistan to Vietnam and northeast China, as well as in southeast Russia, Taiwan, and on the Japanese islands of Honshū and Shikoku. Its coat is usually black, but it may be brown, with white coloration on the chin. The Asiatic black bear can reach 1.6 m (5.25 ft) in length and can weigh up to 200 kg (440 lb).

Asiatic black bears climb trees to collect the fruits and nuts that make up most of their diet; they also gather these morsels on the forest floor. Many Asiatic black bears migrate seasonally—in warmer months they move to higher elevations and in colder months they return to lower elevations. Most Asiatic black bears (except those in the southern parts of their range) fatten up in the fall and then retreat to a den during the winter.

Despite its protection by the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), which regulates and restricts the trade of threatened plants and animals, the Asiatic black bear is highly prized on the black market. It is a popular circus animal, and it remains a favored species for gall bladders and other bear parts used in traditional medicine. The IUCN Red List of Threatened Animals rates this bear as vulnerable. Without strict law enforcement preventing trade on international markets, this bear is at high risk of extinction in the near future.

F.

American Black Bear

American black bears are native to North America, ranging from Alaska and Canada to mountains in northern Mexico. They are secretive, forest-living creatures that have learned to adapt to human-populated areas. They have even been known to winter in suburban back yards without the human residents’ knowledge. After centuries of hunting and habitat destruction following the European colonization of North America, black bear numbers are now stable or increasing, even in the eastern United States where human population is dense. The National Biological Service of the United States Department of the Interior estimates that there are 650,000 to 700,000 black bears in North America.

The smallest of North America’s three bear species, the American black bear can grow to 1.8 m (6 ft) in length and weighs from 40 to 300 kg (90 to 660 lb), with males larger than females. American black bears usually have glossy black coats, although bears with red- and honey-colored coats are common. The Kermode bear, a subspecies of black bear that lives in the rain forests of British Columbia, Canada, sports white fur. The black bear’s mostly vegetarian diet includes grass and green plants, berries and other fruits, and walnuts and acorns, although black bears sometimes eat deer fawns and moose calves. In preparation for fasting during the winter months, a black bear gains up to 1.5 kg (3 lb) per day for two months in the fall.

The American black bear is a mostly thriving species in the United States; only isolated black bear populations in Louisiana, Texas, and Mississippi are listed as threatened by the U.S. Fish and Wildlife Service. Some experts believe that Florida’s small black bear population should have the protection offered by a threatened status. All 32 states with black bear populations have established carefully managed sport-hunting programs. Hunters kill more than 40,000 black bears each year. CITES prohibits the trade in American black bears and bear parts unless a special permit is obtained, certifying that the trade will not harm the species, that the specimen was obtained legally, and for living specimens, that adequate measures were taken to assure safe transport.

G.

Brown Bear

The brown bear is distinguished from other bear species by the presence of a prominent shoulder hump and an upturned snout. The brown bear’s vast range includes parts of Europe, Asia, and North America, where the bears inhabit a variety of habitats, including tundra, dense forests, and deserts. Within these regions, populations are mostly small, isolated, and restricted to remote areas. Coat color in brown bears ranges from a creamy white through various shades of brown to almost jet-black. In certain subspecies of brown bears, such as the grizzly bear found in inland areas, the hairs on the back may be white-tipped, giving the outer coat a grayish, or grizzled, appearance.

Brown bears, along with polar bears, are the largest of the bear species. In general, brown bears range in weight from less than 90 kg (200 lb) for small females to more than 800 kg (1,760 lb) for the largest males. Brown bear populations differ significantly in size, depending largely on available diet. Coastal populations that feed on abundant, fatty salmon in Alaska, for instance, may be three times larger than inland bears, such as grizzlies, which subsist on plant parts, insects, and some meat they steal from wolves or catch themselves. As a result of their fatty fish diet, the Alaskan brown bear, a subspecies that ranges throughout coastal Alaska and western Canada, and the Kodiak bear, a subspecies found on three Alaskan islands that make up the Kodiak archipelago, are the largest brown bears. The Alaskan brown bear may weigh up to 800 kg (1,760 lb) and reach 2.3 m (7.5 ft) in length. The Kodiak bear can grow to 770 kg (1,700 lb) and reach the towering height of 3 m (10 ft).

The brown bear population in Alaska is estimated at 32,000. Elsewhere in North America, brown bears may number fewer than 1,200 individuals, and these animals are listed as threatened by the U.S. Fish and Wildlife Service. In 2007 the population of grizzly bears in Yellowstone National Park was removed from the list of threatened and endangered species, although grizzlies in other areas are still listed as threatened.

The IUCN Red List of Threatened Animals does not list the brown bear, although populations in Western Europe have been greatly reduced by habitat destruction and hunting. Fewer than 10 bears remain in the Pyrenees Mountains between Spain and France, and a similar number survive in the Italian Alps. About 5,000 to 6,000 brown bears live in Eastern Europe, and more than 120,000 live in Russia.

H.

Polar Bear

The polar bear inhabits the polar regions of the Northern Hemisphere, where its white fur blends perfectly with its ice- and snow-covered Arctic habitat. Although primarily found along coasts and ice floes, polar bears may winter in dens up to 48 km (30 mi) inland. Polar bears are one of the largest bear species and can grow to a length of 2 m (7 ft) and weigh up to 800 kg (1,760 lb). Excellent long-distance swimmers, polar bears use their large front feet as paddles and trailing back feet as rudders.

With little vegetation in their frigid environment, polar bears are the most carnivorous of bears, eating primarily seals and sometimes young walruses. They prefer to hunt seals on land or ice but may stalk them from under water. During the summer months when ice floes melt, polar bears are unable to hunt seals and may wander far inland seeking berries, bird eggs, and other foods.

Polar bears are listed as vulnerable on the IUCN Red List of Threatened Species. The United States is considering adding the polar bear to its list of threatened and endangered species under the Endangered Species Act. From 22,000 to 25,000 polar bears make up 19 population groups that live in five Arctic areas of Greenland, Norway, Russia, Canada, and the United States.

Loss of sea ice as a result of global warming may pose the greatest threat to polar bear populations—the bears use the ice for hunting seals and for resting. As much as two-thirds of the world’s population of polar bears may disappear within 50 years as sea ice dwindles. Concentration of pollutants in the Arctic food chain can also affect health and reproduction in polar bears. In addition, polar bear populations remain at risk from ongoing oil and gas exploration and development in the Arctic region. Hunting policies that target adult male polar bears may reduce reproduction success in some regions of Canada.