Polar (or white) bear - a predatory mammal belonging to the Bear family. Ursus maritimus is its Latin name. Where does he live, what does a polar bear eat? How does it breed and interact with other animals? What is its population? Where does the animal live? More on this later in the article.
Origin
It was initially assumed that the separation of the brown and polar bears happened about 45-150 thousand years ago, possibly in the territory occupied by modern Ireland. But in recent studies it was revealed that the separation occurred about 338-934 thousand years ago. About a hundred to two hundred years ago, representatives of the species crossed, resulting in hybridization. As a result, all polar bears inhabiting the planet today are descendants of the resulting hybrids.
External data
The polar bear is considered one of the largest representatives of terrestrial mammals from the order of predators. The growth of individuals can reach 3 m, weight - up to a ton. The most common are males, whose weight is from 400 to 450 kg, and their body length is up to 250 cm. At the withers, the height is from 130 to 150 centimeters. Females weigh significantly less - from 200 to 300 kg. The smallest representatives live on Svalbard, and the largest - in the Bering Sea. White differs from other bears with a flat head and a long neck.
Skin color is black. The fur may have a color from yellowish to white (in the summer, the "fur coat" may turn yellow due to the constant exposure to direct sunlight). The hairs are hollow, and the hair itself is devoid of pigment. Translucent hairs are able to transmit
ultraviolet rays, due to which the cover acquires heat-insulating properties. During UV imaging, the polar bear may appear dark, and sometimes it may even turn green. This happens, as a rule, if there is a white bear in a zoo, in a hot climate. Due to the special structure of the hairs, microscopic algae are planted in them - hence the green color of the skin. In order not to freeze and not slide on ice, the soles of all limbs are lined with wool. Between the fingers is the swimming membrane, on the front of the paws there is stiff bristle. The rest of the article details what polar bears eat.
A life
Polar bears live on fast ice and drift ice. There they hunt and get their main food. What do polar bears eat? Their main food is hare (sea), ringed seal, walrus and other marine animals. He catches his prey, sneaking up from behind cover, or near the holes. As soon as the victim takes his head out of the water, the animal stuns it and pulls it ashore with a paw strike. A polar bear can also overturn the ice floe on which seals sit. Walrus hunting is conducted only on land. As a rule, he eats fat and skin. In the event of severe hunger, the whole carcass of the walrus is devoured. But usually the remains of the captured beast are then eaten up by Arctic foxes. But that’s not all what polar bears eat. On occasion, they can pick up carrion, dead chicks, fish, and eggs. They also include seaweed and grass. If polar bears appear in human-inhabited territories, then they can be seen in garbage cans, not far from landfills for household and food waste.
Even cases of robbery of food warehouses of expeditions by polar explorers are known. All that polar bears eat contributes to the accumulation of vitamin A in their liver. This compound is contained in their body in a sufficiently large amount. There is even evidence of several cases of liver poisoning. Is there a polar bear penguin? Such a question may arise in those who are new to the habitat of these animals. Penguins are known to inhabit the South, and polar bears inhabit the North Pole. Under natural conditions, they can not meet. It was told above that polar bears eat. And representatives of the South Pole are not included in their diet.
Roaming
In accordance with the annual change in the boundaries of the polar ice, polar bears make seasonal transitions. In summer, they retreat closer to the pole, in winter they wander to the southern territories, going to the mainland. Despite the fact that polar bears mainly stay on the ice and coasts, they can lie in the den on the islands or on the mainland, in some cases fifty kilometers from the sea. Hibernation, the duration of which varies from 50 to 80 days, is characteristic, as a rule, of pregnant females. Single females and males occur not annually and for a fairly short period.
Behavior
Despite the seemingly slowness, bears are quick and agile even on land. In the water, they dive and swim quite easily. From getting wet and cold in the water, the bear's body is protected by dense and very thick hair. A special adaptive task is performed by subcutaneous fat with a layer of up to ten centimeters. Masking a predatory beast is greatly facilitated by its light color. Polar bears have very well developed hearing, sight and smell. They can see their prey already for several kilometers, and, for example, they can smell seals for 800 meters.
Breeding
The race starts with polar bears in March and ends in June. In estrus, the female is usually followed by three to four males. By October, female individuals begin to tear out lairs in the sediment. The bears have their favorite territories where they gather (Wrangel Island, for example). Annually in such places there are about 150-200 burrows. In the dens, the bears settle only by mid-November, at the end of the latent stage of gestation of the cubs. The entire pregnancy lasts 230-250 days. At the end or in the middle of the Arctic winter, cubs are born. At the same time, the female herself remains in hibernation until April. It should be said that the bears have a low breeding potential. The first offspring appears in 4-8 years. The birth occurs once every two to three years, in one litter from one to three cubs. As a result, the female brings no more than ten to fifteen cubs throughout her life. Newborns have a weight of 450 to 750 grams. Three months later, with them, the female leaves the den and begins a wandering life. Up to one and a half years, the cubs remain with their mother. Throughout this period, she feeds the cubs with milk.
Social structure
It should be said that mortality among cubs reaches 10-30%. The life expectancy of bears is not more than 25-30 years, the record of longevity in captivity is forty-five years. As a rule, animals are peaceful in relation to representatives of their species. But during the mating season, clashes between males can occur. Sometimes adult males attack cubs, mostly males. Polar bears can interbreed with brown ones. As a result, fertile (reproductive) offspring appear - polar grizzlies.
Population Status and Economic Importance
The polar bear is listed in the Red Book of the Russian Federation as a rare species. Due to the high mortality of young animals and slow breeding, this animal becomes quite easily vulnerable. But even despite this, the population today is considered relatively stable, even growing in some way. Eskimos hunt polar bears for meat and skin. In Russia, animal hunting has been banned since 1956. In other countries (Greenland, Canada and the USA), polar bear hunting is limited. In Russia today there are about 5-7 thousand individuals. In this case, the shooting by poachers is about 150-200 bears per year.