6 slick tricks for keeping warm - six different ways by which animals keep warm

Denise Belick Binderup

### Denise Belick Binderup

How do you keep toasty warm when winter gets freezing cold? Do you bundle up in thick clothes? Snuggle with your family on the sofa? Animals do the same kinds of things to cope with cold. Here are some of their winter warm-ups.

1. FURRY COATS

A mammal's fur coat keeps out the shivery chills. How? Most fur has two layers. The inner layer is short and fuzzy. It traps little pockets of air close to the body, which help hold in the body's heat. The long outer hairs act like an umbrella. They help keep the wind, rain, and snow from getting through to the skin.

Many furry animals, such as wolves and mountain goats, grow extra-thick fur in the fall. Then they're all "layered-up" for the winter!

2. DOWN JACKETS

Do you ever wear a down jacket or vest when you go outside? It can keep you warm on a nippy day. That's because down jackets are filled with the soft, fuzzy down feathers of ducks or geese.

Down works for a bird the same way the inner layer of fuzzy fur works for a mammal. The fluffy down feathers catch and trap little pockets of air next to the bird's body. The air pockets help keep in the bird's body heat.

When the bird puffs up its outer feathers, they can trap even more air. Have you noticed how round and plump birds look when it's cold out? They're not little fatties--they're just puffed up to keep warm!

3. RAINCOATS

It's hard to stay warm if you're wet. Even on a warm day, getting wet can give you the shivers. So if you have to go out in the rain, you probably wear clothes that keep you dry, such as a raincoat, a rain hat, and boots. These things are all waterproof--water rolls right off them.

Animals that live near water have some neat ways to make their bodies water- proof too. Many water birds, such as ducks and swans, keep out the water with oil. Here's how it works: Each bird has an oil gland near its tail. With its bill, the bird smears oil from the gland all over its outer feathers. The oil acts like a raincoat--water rolls right off the bird!

Mammals such as beavers, minks, and otters also use oil to keep dry. Next to each of their long outer hairs is a tiny oil gland. When the animals groom their fur, they spread oil over these hairs. The animals also have a layer of short inner hairs that trap air next to their skin. The air helps keep them warm in cold water.

4. CHUBBY WARMTH

You couldn't survive very long in cold water if you were wearing an ordinary swimsuit. Instead, you'd have to wear a rubbery diving suit. The suit would help hold in your body heat and keep you from freezing.

Whales, seals, and walruses--animals that swim in the world's coldest sea waters--have a layer of fat that works like a diving suit. The fat, called blubber, is right under the animal's skin. It helps keep in body heat, so the animal stays warm, even in cold water. The colder the water is, the more blub- ber an animal needs. Some whales may have a layer of blubber as thick as 20 inches (50 cm).

5. SNUGGLING

Have you ever snuggled close to someone on a chilly day? This keeps you warm in two ways: Scrunching up--pulling your arms and legs in close to your warm body--protects you from the cold. Plus, you can share body heat with the other person.

Animals may do the same thing when they're cold. Squirrels huddle together in a hollow tree. Bluebirds cuddle inside a birdhouse. Bees clump together in a hive, vibrating their flight muscles to keep warm. And in rocky dens, some- times more than 100 snakes twist together. This may protect them from the cold and from drying out.

6. HEATING WITH SNOW

Most people protect themselves from winter wind and cold by going inside. Some animals also find a way to get "indoors"--under the snow! Small mammals such as mice, shrews, and voles make tunnels. The tunnels run along the ground, where it's warmer than the cold air above the snow. The snow acts like a blanket, sheltering the animals from bitter-cold winds.

A few animals make "snow houses" in a different way: They take a nosedive! Birds such as grouse and ptarmigans (TAR-mih-gunz) fly headfirst into soft snowdrifts. There they dig out a bird-sized snow house to protect themselves from the cold wind outside.

Whether they're burrowing birds, blubbery whales, or snuggling squirrels, animals have lots of ways to keep warm in winter. Maybe some of their tricks could work for you!

COPYRIGHT 1996 National Wildlife Federation
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