POLAR BEAR
Ursus maritimus
meaning of Latin name: sea bear
DESCRIPTION: Male polar bears are about twice as big as females. Males can be 8’6” (2.6 m) and females are about 6’11” (2.1 m) long. Males can stand up to 11 feet (3.35 m) tall on their hind legs. Males can weigh 1,800 pounds (800 kg) and females 660 pounds (300 kg).
A polar bear's fur is translucent, reflecting the color of the ice and snow in which it lives. Many factors such as season, angle of light, and staining can affect the color reflected by the fur, and ranges from pure white to light brown.
RANGE/HABITAT: Polar bears are found along Arctic coastlines and ice flows, and are sometimes seen as far as 600 miles from land. Each bear has its own home range, in which it travels throughout the year, usually staying in one area through a season. Polar bears make seasonal migrations of between 1,200 and 2,500 miles (2,000 – 4,000 km) across the ice. They can occasionally swim more than 60 miles (100 km) or more in open water.
BEHAVIOR: Although they are closely related to bears like the grizzly, polar bears are actually considered to be marine mammals since they have characteristics that have adapted them for a marine lifestyle. They obtain almost all of their food from the ocean. They are streamlined for swimming, which allows for agility and endurance for long stays in the water. They even have tiny webs between their toes to help them swim. Also, polar bears have what no other bears have, a layer of blubber that keeps them warm while swimming in the cold Arctic seas.
The polar bear’s coat not only aids in warmth but in camouflage as well. Their favorite food is seal, which they locate with excellent eyesight and a keen sense of smell. If there are no seals to hunt, they will eat small whales, lemmings, and even geese, or scavenge animals already dead. They are one of the most powerful animals on earth. Inuit and Yupik people believe that the polar bear taught them to hunt. The Inuit name for the polar bear is nanook. Except for mothers and cubs, polar bears are usually solitary animals.
MATING AND BREEDING: Females give birth to one or two cubs around December. Cubs are born in a snow den in which they remain for three to five months. They may stay with their mothers for up to three years.
STATUS: Polar bears are a threatened species with a current population of around 21,000-28,000. They are also protected in the United States under the Marine Mammal Protection Act. One of the threats to polar bears is chemicals: tests have shown that some polar bears have traces of DDT and PCBs, showing that even in remote Arctic coastal areas, toxins can be found, carried by water and air. Since polar bears live in land controlled by Canada, the United States, Russia, Norway, and Greenland (Denmark), their fate depends on the people of those countries.
May be reprinted for scientific and educational purposes
Revised 2/06
|
Polar
Bears 