Bear Cub

3 Nov, 2006 in art pottery by admin

Bear Cub

The Life of a Polar Bear Cub

Found throughout the circumpolar Arctic, the polar bear is one of the largest land carnivores. Surviving mainly on a diet of seal, polar bears also eat kelp, scavenge on carcasses, and occasionally even kill a walrus or a small whale. Aptly titled Kings of the North, or Lords of the Arctic, polar bears are truly fascinating animals with unique characteristics, all of which enable them to survive in a harsh and unforgiving world.

So how does a polar bear start out in life? Well, sometime around midsummer, polar bears mate and then go their own separate ways. This is the point where things get very interesting. The fertilized egg divides into a hollow orb of cells called a blastocyst, then free floats in the uterus for four months before attaching to the uterine wall. This delay allows the female polar bear to build up the fat she needs, roughly 400 pounds of it, before the fetus or fetuses begin to develop. This also insures that the cub or cubs are not born too early. Typically, once the blastula begins to develop, one to three embryos will result with actual gestation taking another four months.

Not long after mating, the female polar bear begins preparing a den that she will enter sometime in mid October. Her den will be a hole dug into the deepest snowdrift she can find on a south facing slope and measures approximately 6.5 x 5 x 3 feet with an air vent in the top. There she will spend the winter in hibernation, the cubs being born sometime between November and January. At birth, a baby polar bear weighs around one pound and measures about twelve inches. Blind, deaf, and covered in very fine fuzz, the cubs are totally dependant on mom for food and warmth, spending all of their time nursing and sleeping. Roughly, one month later, the cubs will begin to hear sounds and shortly thereafter, they will open their eyes. At two months, they begin walking around the den. Finally, mom and cubs emerge from the den in March or April by which time the cubs weigh in at around 23 pounds.

For the first 12 weeks, mom and cubs stick close to the den while the cubs get used to the colder temperatures and develop their leg muscles. Polar bear cubs stay with the mom for about 2.5 years. During this time, she fiercely protects them while teaching them how to hunt for food and the basics of survival. The cubs start eating solid food when they are around 3-4 months old but continue to supplement their diet by nursing for another 18 months or so. At around one year of age, the young bears will start trying to hunt on their own, not truly becoming efficient hunters until they reach about two years old. Not long after this, once the mother is again ready to breed, either mom or her new suitor, will chase off the cubs, forcing them to make their way in the world.

Polar bear cubs grow quickly, weighing in at around 99 pounds by the time they reach 8 months old. Once they reach adulthood, a female polar bear will weigh in at 350-550 pounds and can measure over 8 feet tall while a male can easily weigh anywhere from 1,000 to 1,400 pounds and measure over 9 feet tall. Their life span varies but polar bears in the wild have an average life span of span of 20 years with a few living as long as 30.

Survival for polar bear cubs is not high, only 55% will make it to adulthood. They do have some unique factors to help them. A polar bear’s fur is not actually white. Each hair is a clear hollow tube with highly reflective qualities (making it appear white) while their skin is black to absorb heat from the sun. They can also swim for long periods while their thick layers of fat and water repellent fur protect them from the freezing water. Partially webbed front paws and elongated hind paws, which act like rudders, allow the polar bear to swim more efficiently. The pads of their feet, the only place on their bodies with the exception of their nose that is not covered with fur, have a layer of dermal bumps which combined with long hairs between the toes allow for friction against the ice.

Sadly, as of May of 2008, the classification of polar bears upgraded to “threatened” allowing them increased protection under the Endangered Species Act. A combination of melting arctic ice, oil drilling and over hunting have put these fascinating animals in danger of extinction, some experts saying there could be a reduction in the polar bear population of two thirds by 2050. The polar bear is the first animal whose decline ties directly to global warming. Let us hope that with continuing conservation efforts we can still save these magnificent creatures from disappearing along with the arctic ice that they call home.

About the Author

Louise Gilbert is passionate about the state of the environment, protecting endangered wildlife and their habitats, and the humane treatment of animals and pets. Her site can be viewed at www.baby-mammals.com

Is it called polar bear cub or puppy?

Is a baby polar bear a polar bear puppy or polar bear cub, or can either be used interchangeably?

cub

Bear cub falling asleep