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The polar bear is the biggest and baddest of the world's bears, as well as the only all white one. Called "ice bear" in Norway, one of his homes, he lives in five countries around the north pole, but spends much of his time at sea, hunting on the pack ice.
When polar bears are born, they are blind, fuzzy and toothless, and weigh about a pound. They look a lot like a big white rat or a Samoyed puppy. For the first couple of months, all they do is snuggle close to the sow bear for warmth, and nurse. By the time they leave the den at about 2 months old, they weigh close to 35 pounds and are sprouting canine teeth.
Polar bear cubs stay with their mother for the two years they need to acquire the hunting skills to survive on their own. When they're old enough to fend for themselves, ready or not, their mother runs them off and starts looking for a new boyfriend. As a sow breeds only every third year, she can have only three or four litters (twins are usual, but singletons happen) or not more than eight cubs in her life, a very low reproductive rate.
Just like people, polar bear girls grow up faster than boys. Sows are sexually mature at age 4. Boars start getting ideas at about 5 or 6, but don't get to do much about it for some years, as the big guys are more attractive to the ladies and get most of the action.
All Grown Up
A polar bear, male or female, is fully adult when capable of surviving and reproducing. Sows remain fertile until their early 20s, and sometimes longer. Boars get as big as they're likely to get and start to be serious contenders in the mating game at about 10; they can sire cubs until 19 or so.
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