These rules help keep polar bear populations stable. Today, 25, to 40, polar bears roam the Arctic. See KidZone Bibliography for more information. Around the age of four or five the female polar bear can start having babies. They usually only have two cubs and they have these babies in a cave they've dug in a large snow drift. They stay there over winter and come out in spring with the babies. The babies are much smaller than human babies when they're born.
They are the size of a rat and weigh little more than a pound. They can grow to full man size in a year if they have lots of food. Male polar bears may grow 10 feet tall and weigh over pounds. Females reach seven feet and weigh pounds. In the wild polar bears live up to age Despite what we think, a polar bear's fur is not white. Each hair is a clear hollow tube. Polar bears look white because each hollow hair reflects the light.
On sunny days, it traps the sun's infrared heat and keeps the bear warm at 98 degrees F when they're resting. Polar bear fur is oily and water repellent. The hairs don't mat when wet, allowing the polar bears to easily shake free of water and any ice that may form after swimming.
This process is called delayed implantation. After feeding through the summer and fall, gaining as much weight as possible, pregnant female polar bears prepare to enter maternity dens to give birth to their cubs. To build a den, the female digs a small snow cave in a snowdrift —just large enough for her to turn around.
She then waits for the snow to close the entrance tunnel and completely hide the den under the snow. Wild polar bear cubs are most often born in December. The mother gives birth to cubs, with twins most common. The family remains in the den until spring. She is devoted to nursing and caring for her cubs. Totally dependent on their mothers, newborn cubs are blind, toothless, and covered with soft white fur.
Polar bear families generally emerge from their dens in March or April when the cubs are strong enough to survive in outside Arctic conditions and make the trek to sea ice. Now, mother bears can start teaching their young how to hunt seals on the ice and survive in the Arctic.
Polar bear cubs generally stay with their mothers for 2. Between the time they leave their mother and are mature enough to mate, polar bears are called subadults. Polar bears are considered adults when they are old enough to mate.
For females, this is ages , for males By the time they reach adulthood, adult males normally weigh kg , lb. Adult females usually weigh kg lb , though some can be larger.
In the wild, polar bears live an average of 15 to 18 years, although biologists have tagged a few bears in their early 30s. Join us in our efforts to encourage leaders to make a swift transition away from fossil fuels and to renewable energy sources, by spreading awareness about the real and pressing threat of climate warming. Conservation Concerns.
Polar bears hold great spiritual and cultural significance for Inuit communities. Polar bears are marine mammals Although polar bears spend a lot of time on land, they are perfectly suited for life in the ocean. Polar bears are the largest land carnivore Male polar bears can grow up to 2. Polar bears are tiny and helpless at birth Although polar bears grow to be huge, they start their life extremely small and helpless.
Polar bears typically give birth to twins Although polar bears can give birth to one to three cubs, they most commonly give birth to twins. Polar bears need sea ice Polar bears are dependent on sea ice to catch seals, as they are most efficient as ambush hunters. Polar bears are mostly Canadian There are 19 subpopulations of polar bears in the world, which are based on geographic sea-ice regions.
Polar bears can fast for up to eight months When the summer rolls around and sea ice retreats, polar bears head towards land to live out the ice free season. Facebook Twitter Google Plus.
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