GIANT PANDA

GEOGRAPHIC DISTRIBUTION:

Giant pandas live in a few mountain ranges in central China, in Sichuan, Shaanxi, and Gansu provinces. They once lived in lowland areas, but farming, forest clearing, and other development now restrict giant pandas to the mountains.

HABITAT:

Giant pandas live in broadleaf and coniferous forests with a dense understory of bamboo, at elevations between 5,000 and 10,000 feet. Torrential rains or dense mist throughout the year characterizes these forests, often shrouded in heavy clouds.

PHYSICAL DESCRIPTION:

The giant panda, a black-and-white bear, has a body typical of bears. It has black fur on ears, eye patches, muzzle, legs, and shoulders. The rest of the animal's coat is white. Although scientists do not know why these unusual bears are black and white, some speculate that the bold coloring provides effective camouflage into their shade-dappled snowy and rocky surroundings. The panda's thick, wooly coat keeps it warm in the cool forests of its habitat. Giant pandas have large molar teeth and strong jaw muscles for crushing tough bamboo. Many people find these chunky, lumbering animals to be cute, but giant pandas can be as dangerous as any other bear.

SIZE:

About the size of an American black bear, giant pandas stand between two and three feet tall at the shoulder (on all four legs), and reach four to six feet long. Males are larger than females, weighing up to 250 pounds in the wild. Females rarely reach 220 pounds.

STATUS:

The giant panda is listed as endangered in the World Conservation Union's (IUCN's) Red List of Threatened Species. There are about 1,600 left in the wild. More than 300 pandas live in zoos and breeding centers around the world, mostly in China.

LIFE SPAN:

Scientists aren't sure how long giant pandas live in the wild, but they are sure it's shorter than lifespans in zoos. Chinese scientists have reported zoo pandas as old as 35. The National Zoo's Hsing-Hsing died at age 28 in 1999.

DIET:

A wild giant panda’s diet is almost exclusively (99 percent) bamboo. The balance consists of other grasses and occasional small rodents or musk deer fawns. In zoos, giant pandas eat bamboo, sugar cane, rice gruel, a special high-fiber biscuit, carrots, apples, and sweet potatoes.

SOCIAL STRUCTURE:

Adult giant pandas are generally solitary, but they do communicate periodically through scent marks, calls, and occasional meetings. Offspring stay with their mothers from one and a half to three years.

The giant panda has lived in bamboo forests for several million years. It is a highly specialized animal, with unique adaptations.

FEEDING ADAPTIONS:

Millions of Zoo visitors enjoy watching giant pandas eat. A panda usually eats while sitting upright, in a pose that resembles how humans sit on the floor. This posture leaves the front paws free to grasp bamboo stems with the help of a "pseudo thumb," formed by an elongated and enlarged wrist bone covered with a fleshy pad of skin. The panda also uses its powerful jaws and strong teeth to crush the tough, fibrous bamboo into bits.

A giant panda’s digestive system is more similar to that of a carnivore than an herbivore, and so much of what is eaten is passed as waste. To make up for the inefficient digestion, a panda needs to consume a comparatively large amount of food—from 20 to 40 pounds of bamboo each day—to get all its nutrients. To obtain this much food means that a panda must spend 10 to 16 hours a day foraging and eating. The rest of its time is spent mostly sleeping and resting.

WATER:

Wild giant pandas get much of the water they need from bamboo, a grass whose contents are about half water. (New bamboo shoots are about 90 percent water.) But giant pandas need more water than what bamboo alone can provide. So almost every day wild pandas also drink fresh water from rivers and streams that are fed by melting snowfall in high mountain peaks. The temperate forests of central China where giant pandas live receive about 30 to 40 inches of rain and snow a year. Charleston, West Virginia—a city with a similar temperate climate—receives about the same amount of rain and snow: an average of 42.5 inches a year.

REPRODUCTION:

Giant pandas reach breeding maturity between four and eight years of age. They may be reproductive until about age 20. Female pandas ovulate only once a year, in the spring. A short period of two to three days around ovulation is the only time she is able to conceive. Calls and scents draw males and females to each other.

Female giant pandas give birth between 95 and 160 days after mating. Although females may give birth to two young, usually only one survives. Giant panda cubs may stay with their mothers for up to three years before striking out on their own. This means a wild female, at best, can produce young only every other year; in her lifetime, she may successfully raise only five to eight cubs. The giant pandas’ naturally slow breeding rate prevents a population from recovering quickly from illegal hunting, habitat loss, and other human-related causes of mortality.

DEVELOPMENT:

At birth, the cub is helpless, and it takes considerable effort on the mother’s part to raise it. A newborn cub weighs three to five ounces and is about the size of a stick of butter. Pink, hairless, and blind, the cub is 1/900th the size of its mother. Except for a marsupial (such as the kangaroo or opossum), a giant panda baby is the smallest mammal newborn relative to its mother's size.

Cubs do not open their eyes until they are six to eight weeks of age and are not mobile until three months. A cub may nurse for eight to nine months. A cub is nutritionally weaned at one year, but not socially weaned for up to two years.

LIFESTYLE:

A wild panda spends much of its day resting, feeding, and seeking food. Unlike other bears from temperate climates, giant pandas do not hibernate. Until recently, scientists thought giant pandas spent most of their lives alone, with males and females meeting only during the breeding season. Recent studies paint a different picture, in which small groups of pandas share a large territory and sometimes meet outside the breeding season. Much remains to be learned about the secret lives of these elusive animals, and every new discovery helps scientists in their battle to save this species.