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Seals

in Animals

ImageCan you bend over backward and touch your nose to your feet? Can you hold your breath underwater for two hours? Can you dive hundreds of feet in icy water? Of course you can’t. You’re not a seal.

WHAT ARE SEALS?

Seals live in the ocean, but they breathe air just as dogs, whales, and you do. Like those animals, seals are mammals. Some seals are the size of small cars. Other seals are no bigger than the average dog.

Seals are excellent swimmers. Their bodies are flexible. They have flippers at the ends of their arms and legs to help them swim. Some seals can swim as fast as 25 miles (40 kilometers) per hour. Others can dive down hundreds of feet. These seals can store enough oxygen to stay underwater for more than two hours.

Seals don’t walk well on land. Some seals can waddle along by swinging their flippers back and forth. Other seals have to flop around on their bellies to move on land. Some seals use their flippers as paddles to slide across ice. These seals can slide along as fast as 16 miles (25 kilometers) per hour!

ARE THERE DIFFERENT KINDS OF SEALS?

There are lots of kinds of seals. Scientists group them into three main types: true seals, eared seals, and walruses.

True seals don’t have ears that stick out. Instead, they have small openings that lead to ears inside their head. True seals also have short flippers that are nearly useless for moving on land. They use their short flippers to slide across ice.

Eared seals include sea lions and fur seals. They have tiny ears you can see. They also have strong flippers that they can use to lift their bodies off the ground.

Walruses have wrinkled skin, lots of whiskers, and large tusks. They use their tusks as hooks to pull themselves out of the water onto floating blocks of ice.

WHERE DO SEALS LIVE?

Seals live in the ocean. Most seals live in cold waters near the North and South poles. Walruses live in Arctic waters. Some true seals live under the ice. They find cracks and holes in the ice so they can come up for air.

Some seals, such as monk seals, love warm, clear waters. They live near Hawaii or in the Mediterranean Sea.

HOW DO SEALS STAY WARM?

Adult seals have a thick layer of fat, called blubber, under their skin. Blubber keeps seals warm in cold water. Seals also use the blubber for energy when they can’t find food. Seals can live off the stored fat in blubber for weeks or even months.

Most baby seals don’t have a layer of blubber yet. They develop a thick fur coat to stay warm. Some seals shed their fur when they get older. Others, such as the fur seal, keep a thick coat their entire life. A fur seal has more hairs on one centimeter of its skin than you have on your entire head!

WHAT DO SEALS EAT?

Most seals eat fish, but different kinds of seals eat different things. The leopard seal, which lives near the South Pole, hunts penguins, seabirds, smaller seals, fish, squid, and krill (small, shrimplike creatures). Sometimes, it feeds off dead whales. Leopard seals even chase people who are standing on ice or scuba diving!

Sea lions and walruses sometimes eat other seals. More often, they eat fish. Walruses dig for clams, worms, shellfish, and other animals in the mud. They also dive deep and use their large “mustache” of whiskers to help them feel for food on the dark ocean floor. A big walrus can eat about 100 pounds (45 kilograms) of shellfish in one day.

DO SEALS COMMUNICATE?

Seals make and hear sounds underwater. They whoop, scream, bark, moan, and wail. Seals use these noises to find mates and scare away rivals. Some types of seals sing songs that last more than a minute.

ARE SEALS ENDANGERED?

Large sharks and killer whales hunt and eat seals. Polar bears kill seals on land and on ice in the Arctic. But people are the biggest threat to seals. People have hunted seals for food, skins, and blubber.

The northern elephant seal has nearly died out. Hawaiian and Mediterranean monk seals are also endangered, and a third type of monk seal is already extinct.

Many countries outlawed seal hunting in 1911. Since then, some seals have made a comeback. Others have not. Oil spills and pollution in the ocean still cause many seals to die.

Source: Microsoft ® Encarta