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- a predator belonging to the suborder Canidae, the bear family and the genus bear. This unique mammal is an endangered species. Its most famous names are umka, oshkuy, nanuk and polar bear. It lives in the north, feeds on fish and smaller animals, and sometimes attacks humans. Just a few centuries ago, its population exceeded hundreds of thousands of individuals, but their systematic destruction forced conservationists to sound the alarm.
Where does the polar bear live?
The polar bear lives exclusively in the subpolar regions of the northern hemisphere, but this does not mean that the animal lives everywhere where there is non-melting Arctic snow. Most bears do not go further than 88 degrees north latitude, but the extreme point of their distribution in the south is the island of Newfoundland, the few inhabitants of which risk their lives every day trying to get along with a dangerous predator.
Residents of the Arctic and tundra zones of Russia, Greenland, the USA and Canada are also familiar with the polar bear. Most animals live in areas with drifting, multi-year ice, where many seals and walruses also live. Most often, the bear can be seen near a large hole, on the edge of which it freezes in anticipation of a seal or fur seal rising from the depths.
It is impossible to accurately determine the continent where the polar bear lives. The most extensive populations of these animals were named after the location of their main concentration. So, most predators prefer:
- the eastern shores of the Kara and East Siberian seas, the cold waters of the Laptev Sea, the New Siberian Islands and the Novaya Zemlya archipelago (Laptev population);
- the shores of the Barents Sea, the western part of the Kara Sea, the islands of the Novaya Zemlya archipelago, Franz Josef Land and Spitsbergen (Kara-Barents Sea population);
- Chukchi Sea, northern Bering Sea, eastern East Siberian Sea, Wrangel and Herald Islands (Chukchi-Alaskan population).
Directly in the Arctic, polar bears are rarely found, preferring more southern and warmer seas, where they have a better chance of survival. The habitat is variable and is associated with the boundaries of polar ice. If the Arctic summer drags on and the ice begins to melt, then animals move closer to the pole. With the onset of winter, they return to the south, preferring ice-covered coastal areas and the mainland.
Description of a polar bear
Polar bears, described below, are the largest mammalian predators on the planet. They owe their significant dimensions to their distant ancestor, who became extinct thousands of years ago. The giant polar bear was at least 4 meters long and weighed about 1.2 tons.
The modern polar bear is somewhat inferior in both weight and height. Thus, the maximum length of a polar bear does not exceed 3 meters with a body weight of up to 1 ton. The average weight of males does not exceed 500 kilograms, females weigh 200-350 kilograms. The height of an adult animal at the withers is only 1.2-1.5 meters, while the giant polar bear reached a height of 2-2.5 meters.
Coat, structural features of the body and head
The entire body of the polar bear is covered with fur, which protects it from severe frosts and allows it to feel comfortable even in icy water. Only the nose and paw pads are devoid of fur. The color of the fur coat can be crystal white, yellowish and even green.
In reality, the animal’s fur is devoid of pigmentation, it is colorless, the hairs are hollow, dense, hard, located at a minimum distance from each other. There is a well-developed undercoat, under which black skin with a 10-centimeter layer of fat is found.
The white coat color serves as an ideal camouflage for the animal. It is not easy for even an experienced hunter to spot a hidden bear, but seals and walruses often become victims of this cunning and cruel predator.
Structure of the torso, head and legs
Unlike a grizzly bear, a polar bear's neck is elongated, its head is flat, its front part is elongated, and its ears are small and rounded.
These animals are skilled swimmers, which is achieved due to the presence of membranes between their toes and is determined by where the polar bear lives most of the year. At the moment of swimming, it does not matter how much a polar bear weighs; thanks to its membranes, it can easily overtake even the fastest prey.
The legs of the predator are columnar, ending in powerful paws. The soles of the feet are covered with wool, which serves as ideal protection against freezing and slipping. The front parts of the paws are covered with hard bristles, under which sharp claws are hidden, allowing them to hold prey for a long time. Having captured the prey with its claws, the predator then uses its teeth. Its jaws are powerful, its incisors and fangs are well developed. A healthy animal has up to 42 teeth and no facial vibrissae.
All representatives of this species have a tail, the polar bear is no exception in this regard. Its tail is small, from 7 to 13 centimeters long, lost against the background of the elongated fur of the back of the back.
Endurance
The polar bear is an extremely resilient animal; despite its apparent clumsiness, it is capable of traveling up to 5.6 kilometers per hour on land and up to 7 kilometers per hour in water. The average speed of a predator is 40 kilometers per hour.
Polar bears hear and see well, and their excellent sense of smell allows them to smell prey located at a distance of 1 kilometer from them. The animal is able to detect a seal hiding under several meters of snow, or hiding at the bottom of a hole, even if it is at a depth of over 1 meter.
How long does a polar bear live?
Oddly enough, polar bears live longer in captivity than in their natural habitat. The average life expectancy in this case does not exceed 20-30 years, while a zoo inhabitant is quite capable of living over 45-50 years. This is due to the shrinking food supply, the annual melting of glaciers and the ongoing extermination of predators by humans.
In Russia, polar bear hunting is prohibited, but in other countries there are only some restrictions on this matter, allowing the extermination of no more than several hundred predators per year. In most cases, such hunting has nothing to do with the real needs for meat and skins, and therefore is a real barbarism in relation to this beautiful and powerful animal.
Features of character and lifestyle
The polar bear is considered a cruel predator that even attacks people. The animal prefers a solitary lifestyle; males and females gather together only during the rutting period. The rest of the time, bears move exclusively through their own territory, conquered from their other brothers, and this applies not only to males, but also to females with newborn offspring.
Hibernation
Unlike its brown counterparts, the polar bear does not have to hibernate for the winter. Most often, only pregnant females sleep on the eve of giving birth. Adult males do not sleep every season; the duration of hibernation is no more than 80 days (a brown bear sleeps from 75 to 195 days a year).
Reproduction of polar bears, care of offspring
Polar bears behave quite peacefully towards each other; most fights occur between males during the rutting period. At this time, not only adult animals can suffer, but also cubs, which prevent the female from re-participating in mating games.
Animals become sexually mature when they reach 4 or 8 years of age, while females are ready to bear offspring 1-2 years earlier than males.
The mating season lasts from late March to early June. One female can be pursued by up to 7 males. Gestation of offspring takes at least 250 days, which corresponds to 8 months. Pregnancy begins with a latent stage, which is characterized by a delay in embryo implantation. This feature is associated not only with the physiology of the animal, but also with its living conditions. The female must prepare for fetal development and long hibernation. Around the end of October, she begins to equip her own den, and for this purpose sometimes travels hundreds of kilometers. Many females dig dens near existing buildings. Thus, on the Wrangel and Franz Josef islands there are at least 150 nearby dens.
Embryo development begins in mid-November, when the female is already sleeping. Its hibernation ends in April and at about the same time 1-3 cubs, weighing from 450 to 700 grams each, appear in the den. The exception is the birth of 4 cubs. The babies are covered with thin fur, which practically does not protect them from the cold, therefore in the first weeks of their life the female does not leave the den, maintaining her existence at the expense of accumulated fat.
Newborn cubs feed exclusively on mother's milk. They do not open their eyes immediately, but a month after birth. Two-month-old babies begin to crawl out of the den, only to leave it completely when they reach 3 months. At the same time, they continue to feed on milk and stay close to the female until they reach 1.5 years. Small cubs are practically helpless, so they often become prey for larger predators. The mortality rate among polar bears under 1 year of age is at least 10-30%.
A new pregnancy in a female occurs only after the death of the offspring, or their introduction into adulthood, that is, no more than once every 2-3 years. On average, no more than 15 cubs are born from one female during her entire life, half of which die.
What does a polar bear eat?
The polar bear feeds exclusively on meat and fish. Its victims include seals, ringed seals, bearded seals, walruses, beluga whales and narwhals. Having caught and killed the prey, the predator begins to eat its skin and fat. This part of the carcass is what polar bears eat in most cases. They prefer not to eat fresh meat, making an exception only during periods of prolonged hunger strikes. Such a nutritious diet is necessary for the accumulation of vitamin A in the liver, which helps to survive a long winter without consequences. What the polar bear does not eat is picked up by the following scavengers - arctic foxes and wolves.
To satiate, a predator needs at least 7 kilograms of food. A hungry bear can eat 19 kilograms or more. If the prey is gone and there is no strength left to pursue it, then the animal feeds on fish, carrion, bird eggs and chicks. At such times, the bear becomes dangerous to humans. He wanders to the outskirts of villages, feeding on garbage and tracking down lonely travelers. In hungry years, bears also do not disdain algae and grass. Periods of long hunger strikes mainly occur in the summer, when the ice melts and retreats from the shore. At this time, the bears are forced to spend their own fat reserves, sometimes starving for over 4 months in a row. The question of what a polar bear eats becomes irrelevant during such periods, since the animal is ready to feed on literally everything that moves.
Hunting
The bear tracks its prey for a long time; sometimes it stands for hours near the hole, waiting for the seal to come up for air. As soon as the prey's head is above the water, the predator strikes it with a powerful paw. He grabs the stunned carcass with his claws and drags him to land. To increase its chances of being caught, the bear expands the boundaries of the hole and practically immerses its head in the water in order to have time to notice the appearance of prey.
Seals cannot spend all their time in the water; they need to rest sometimes, which is what polar bears take advantage of. Having noticed a suitable seal, the bear quietly swims up and turns over the ice floe on which it is resting. The seal's fate is sealed. If a walrus became the bear's prey, then everything is not so simple. Walruses have powerful defenses in the form of their front tusks, with which they can easily pierce an unlucky attacker. An adult walrus can be much stronger than a bear, especially if it is young and does not yet have sufficient experience in such battles.
With this in mind, bears attack only weak or young walruses, doing this exclusively on land. The prey is tracked for a long time, the bear creeps up to the closest possible distance, after which it makes a jump and leans on the victim with all its weight.
In its natural habitat, a bear has a minimal number of enemies. If an animal is wounded or sick, it can be attacked by walruses, killer whales, wolves, arctic foxes and even dogs. A healthy bear is larger than any of the named predators and can easily cope with even several opponents attacking en masse. A sick animal takes a significant risk and often prefers to avoid battle by resting in a den.
Sometimes small bear cubs, whose mother has gone hunting or is inattentively watching them, become prey for wolves and dogs. The life of the bear is also threatened by poachers who are interested in killing the animal in order to obtain its luxurious skin and large amounts of meat.
Family ties
First appeared on the planet approximately 5 million years ago. The polar bear separated from its brown ancestors no more than 600 thousand years ago, and yet its closest relative continues to be the ordinary brown bear.
Both the polar bear and the brown bear are genetically similar, therefore, as a result of crossing, completely viable offspring are obtained, which can subsequently also be used to produce young animals. Black and white bears will not naturally be born, but the young will inherit all the best qualities of both individuals.
At the same time, polar and brown bears live in different ecological systems, which affected the development of a number of phenotypic characteristics in them, as well as differences in nutrition, behavior and lifestyle. The presence of significant differences in all of the above allowed us to classify the brown bear, or grizzly, as a separate species.
Polar bear and brown bear: comparative characteristics
Both polar and brown bears have a number of distinctive features, the essence of which boils down to the following:
| Polar bear, or Umka | Black and brown bear | |
| Length | At least 3 meters | 2-2.5 meters |
| Body mass | 1-1.2 tons | Up to 750 kilograms maximum |
| Subspecies | Doesn't have any | The brown bear has a large number of subspecies that have spread throughout the world. |
| Physiological characteristics | Elongated neck, medium-sized flattened head. | Thick and short neck, massive rounded head. |
| Habitat | The southern border of the polar bear's habitat is the tundra. | Brown bears are distributed throughout the planet, at the same time preferring more southern regions. The limit of their habitat in the north is the southern border of the tundra. |
| Food preferences | The polar bear eats meat and fish. | In addition to meat, the brown bear eats berries, nuts, and insect larvae. |
| Hibernation time | Hibernation does not exceed 80 days. Mostly pregnant females go on vacation. | The duration of hibernation is from 75 to 195 days, depending on the region where the animal lives. |
| Gon | March-June | May - July |
| Offspring | No more than 3 cubs, most often 1-2 newborns in a litter. | 2-3 cubs are born, in some cases their number can reach 4-5. |
Both polar and brown bears are dangerous predators, which leads to natural questions about who is stronger in a fight, a polar bear or a grizzly bear? It is impossible to give an unambiguous answer to the question posed about who is stronger, or who will win, a polar bear or a brown one. These animals almost never intersect. In a zoo, they behave quite peacefully.
Interesting facts about the polar bear
There are many legends and myths about the polar bear. At the same time, some features of his behavior are so interesting that they deserve the attention of not only lovers of legends, but also young admirers of wildlife. Today the following is known about the polar bear:
- The largest predators are found in the Barents Sea; smaller animals prefer the island of Spitsbergen and the area near it.
- In photographs taken under ultraviolet light, the polar bear's fur appears black.
- Starving bears can cover enormous distances, moving not only on land, but also by swimming. In this, both the polar and the brown bear are similar. A bear swim lasting over 9 days was recorded. During this time, the female traveled over 660 kilometers across the Beaufort Sea, lost 22% of her weight and her one-year-old cub, but remained alive and was able to get ashore.
- The polar bear is not afraid of humans; a hungry predator is capable of making him its prey, tirelessly chasing him for many days. In the city of Churchill, which belongs to the Canadian province of Manitoba, there is a special place where bears that wander into the settlement are temporarily imprisoned. The existence of a temporary zoo is a necessary measure. Unfrightened by human presence, a hungry predator can enter a house and attack a person. After an overexposure and a hearty meal, the bear leaves the city less aggressive, which allows us to hope that it will not return soon.
- According to the Eskimos, the polar bear embodies the forces of nature. A man cannot call himself such until he enters into an equal confrontation with him.
- The giant polar bear is the ancestor of the modern bear.
- In 1962, a bear weighing 1,002 kilograms was shot in Alaska.
- The bear is a warm-blooded animal. Its body temperature reaches 31 degrees Celsius, which makes it quite difficult for the predator to move quickly. Running for a long time can cause your body to overheat.
- Children are introduced to the image of the polar bear through such cartoons as “Umka”, “Elka” and “Bernard”.
- The beloved “Bear in the North” candy also features an image of a polar bear.
- The official polar bear day is February 27th.
- The polar bear is one of the symbols of the state of Alaska.
Polar bears are considered to be insufficiently fertile, which is why their population is recovering extremely slowly. According to a check carried out in 2013, the number of bears in Russia did not exceed 7 thousand individuals (20-25 thousand individuals worldwide).
The first ban on the extraction of meat and skins of these animals was introduced in 1957, due to their almost complete extermination by local residents and poachers. Polar bears, whose habitat has been disturbed, are encroaching on human property.
Many of us believe that polar bears have white fur, but in reality this is not so: the animals’ hair, like the undercoat, is transparent and completely colorless. And they appear white to us because there is an air pocket inside each guard hair. When a light beam consisting of all the colors of the rainbow hits the wool, the colors from the air pockets are reflected and mix to create a white color.
Depending on the season and the location of the Sun, the animal’s fur can be not only white, but yellow or brown (bears living in captivity can even be green due to algae in artificial reservoirs). But if someone managed to shave off all the fur from an animal, they would be surprised to discover that the skin of a polar bear is black. The dark skin helps absorb and retain the sun's rays, protecting the predator from the Arctic frosts.
The polar or polar bear is the largest predatory mammal that lives on the surface of the earth (second only to the elephant seal). He is the closest relative of the brown bear and belongs to the bear family. In nature, there are about fifteen species of polar bear, and the total number of animals is about twenty-five thousand.
You can meet these animals in the subpolar latitudes of the northern hemisphere, starting from Newfinland and ending at 88° N. sh., and they live on ice floating in the Arctic off the coast of Eurasia and America, so they can only be classified as terrestrial inhabitants only conditionally.
If you think about the natural zone in which polar bears live, you might be surprised: they are the only large predators in the Arctic, ideally adapted for normal existence in polar latitudes. For example, during snow storms they dig holes in the snowdrifts, lie down in them and, without going anywhere, wait out the elements.
The size and weight of these animals largely depend on their place of residence: the smallest animals according to description live on Spitsbergen, while the largest ones live in the Bering Sea. The average height of a bear at the withers reaches about one and a half meters, while the weight of males significantly exceeds the weight of females:
- The weight of males ranges from 400 to 680 kg, length - about three meters (the mass of large lions and tigers does not exceed 400 kg);
- The weight of females ranges from 200 to 270 kg, the length is about two meters.
According to the description, the polar bear differs from other representatives of its species by its greater weight, powerful sloping shoulders, flat head and longer neck.
There is fur on the soles of the paws, which allows the animal not to slip and freeze. There is a membrane between the toes, and the structure of the paws allows polar bears to swim gracefully, gracefully and quickly. Large curved claws are not only capable of holding even strong prey, but also allow it to easily move on slippery ice and climb over blocks.
It is noteworthy that these animals are quite capable of reaching speeds of up to 10 km/h and swimming about 160 km without stopping. They are also very good divers and can stay underwater for about two minutes.
The polar bear does not freeze thanks to a thick, about 10 cm, layer of subcutaneous fat on the back, back of the body and hips, as well as very warm fur, which retains the heat generated. The predator's fur is very thick and dense; it not only reliably retains heat, but also protects the animal's body from getting wet, and its white color makes it possible to camouflage perfectly.
The teeth of polar bears are also noteworthy: in cross-section, they form annual circles of two cement layers. The tooth is tightly attached to the jaw, as the root of the teeth is connected to it by a layer of cement that grows throughout the bear's life.
At different times of the year, the layer grows differently and seems to consist of two parts: the winter layer is thinner than the summer layer, which is located above it, and the older the animal, the smaller the distance between the rings.
Way of life
Although polar bears give the impression of being a clumsy animal, in fact they are very fast, agile, and excellent at diving and swimming, both on land and in water. For example, when escaping danger, a polar bear can move at a speed of about 7 km/h without any problems. They are capable of covering considerable distances: the record for the longest movement was recorded for a polar bear, who, together with her baby, swam 685 km across the sea from Alaska to the north in search of a new home.
The main reason why she did this was that the place where the polar bears live was no longer suitable due to the melting of the ice floes: the seals left their place of residence. Unfortunately, the cub died during such a nine-day swim, and her weight decreased by twenty percent.
Despite their ability to develop high speeds, polar bears still prefer to move slowly and without haste: although temperatures in the Arctic can drop to minus forty, these predators usually experience problems not with freezing, but with overheating (especially when running).
Animals also do not live in one place for a long time and move along with the ice, which floats closer to the pole in the summer, and to the south in the winter, while once near the continent, the predator comes to land. The polar bear prefers to be either on the coast or on glaciers, and in winter it can easily set up a den for itself at a distance of 50 km from the sea.
It is worth noting that the female sleeps the longest during pregnancy (two to three months), while males and non-pregnant female bears hibernate for a short period, and not every year. When they go to bed, they always cover their nose with their paw: this helps them conserve heat.
When they talk about where polar bears live, ice floes immediately come to mind - it is there that these predators are able to find food for themselves: seals, ringed seals, walruses, bearded seals, and other sea animals that are part of the predator’s diet live here. During the year, he travels about one and a half thousand kilometers in search of food. Thanks to the huge reserves of subcutaneous fat, it is able to go without food for quite a long time, but if the hunt is successful, it can easily eat up to 25 kg of meat at a time (usually a bear catches a seal once every three to four days).
Thanks to its white color, excellent hearing, perfect vision and excellent sense of smell, the bear is able to smell its prey several kilometers away (a seal at a distance of 32 km). It catches prey, sneaking up from behind shelters, or watches for it near holes: as soon as the prey sticks its head out of the water, it stuns it with its paw and pulls it out. But for some reason, polar bears hunt on the shore very rarely.
Sometimes, swimming up to an ice floe where seals are resting, he capsizes it and catches prey in the water (it is these animals that mainly make up his diet). But a polar bear can cope with a heavier and stronger walrus only on solid ground, where it becomes clumsy.
It is interesting that the polar bear does not eat its entire prey, but only the fat and skin, everything else only if it is very hungry (polar foxes, arctic foxes, and seagulls eat the carcass after it). If there is no usual food, the polar bear feeds on carrion and does not hesitate to eat dead fish, eggs, chicks and even algae. After a meal, a polar bear spends at least twenty minutes cleaning itself, otherwise the wool will reduce its thermal insulation properties.
Thanks to this method of feeding, the polar predator receives a sufficient amount of vitamin A from its prey, which is deposited in its liver in such quantities that more than one case of liver poisoning of this animal has been recorded.
Polar bear camouflage
Polar bears are capable of perfect camouflage, and they are able to become invisible not only to their prey, but even to the infrared cameras with which scientists monitor predators. This was discovered by zoologists during a flight over the Arctic, which was made with the aim of counting the population of these animals. The equipment failed to notice the bears, since they completely merged with the surrounding ice. Even infrared cameras could not detect them: only eyes, black noses and breathing were reflected.
Bears have become invisible due to the fact that with the help of infrared cameras it is possible to see not only temperature indicators of the surface, but also the radiation that comes from the observed objects. In the case of polar bears, it turned out that their fur had radio-emitting properties similar to those of snow, which is why cameras were unable to record the animals.
Offspring
A she-bear gives birth for the first time no earlier than four years of age (and sometimes the first birth occurs at eight). She gives birth to no more than three cubs every two to three years. The mating season usually lasts from March to June, with one female followed by about three to four males, who constantly fight with each other, and adults can even attack and kill cubs. Polar bears can interbreed with brown bears, resulting in offspring that, unlike many other animal species, are also capable of reproducing.
The female bears prepare to give birth in October, starting to dig dens near the coast in the snow drifts. To do this, females often gather in one place; for example, about two hundred dens appear annually on Wrangel Island. They do not settle in them immediately, but in mid-November, and hibernate until April. Pregnancy lasts up to 250 days and the cubs appear blind and deaf, usually in the middle or end of the Arctic winter (their eyes open after a month).
Despite the impressive size of an adult, newly born babies are not much longer than a rat, and their weight ranges from 450 to 750 grams. When the cubs are about three months old and gain weight, they begin to gradually leave the den with the mother bear, gradually switching to a wandering lifestyle. The cubs live with their mother for three years, and until they are one and a half years old, she feeds them with milk, while at the same time feeding them seal blubber. The mortality rate among babies is quite high and ranges from 10 to 30%.
Animal life in the modern world
Polar bears are listed in the IUCN Red List: despite the fact that their numbers are considered stable and even growing, the slow reproduction of white predators, poaching (about 200 animals are killed annually) and high mortality among cubs make the population easily vulnerable, and in some places they have disappeared at all.
Recently, a sharp decrease in population has been recorded in Russia: animals living in the region of Yakutia and Chukotka have completely disappeared in some areas. The lifespan of these predators in nature is about 25 years, while in captivity they can live up to forty-five.
In addition to poachers, the lives of polar bears are affected by global warming: over the last century, air temperatures in the Arctic have risen by five degrees Celsius, which is why the area of glaciers on which these animals actually live is constantly shrinking. This directly affects the population of seals, which are their main food, allowing them to accumulate the necessary fat reserves.
During melting, the ice becomes unstable, as a result of which bears are forced to go to the coast, where there is not enough food for them, and they significantly lose weight, which negatively affects future cubs.
Another important problem is oil, which is present in considerable quantities in the sea water around drilling rigs. While thick fur protects bears from dampness and cold, if it becomes stained with oil, it loses its ability to retain air, causing the insulating effect to disappear.
As a result, the animal cools down faster, and the black skin of the polar bear runs the risk of overheating. If a predator also drinks such water or simply licks it off the fur, this will lead to kidney damage and other diseases of the gastrointestinal tract.
My daughter really loves watching the cartoon about Umka. And today she asked where Umka lives and whether he is friends with penguins. Then a series of questions followed, and I had to answer. I’ll tell you about all the subtleties of my answer.
Polar bear habitats
Polar bears, as my daughter expected, live at the North Pole. But they do not meet with penguins in natural conditions. This is because they live on different ends of the globe. Penguins live exclusively at the South Pole, and polar bears live exclusively at the North Pole. The largest part of these bears lives in Northern Canada. In Russia Polar bears live on Vrungel Island.
Survival in extreme conditions
Polar bears look very cute and funny, but they live in the harshest places. What helps them survive:
Bears feed mainly on seals. In one season, a polar bear can eat up to 50 seals. But they eat meat very rarely. They mainly eat skin and fat, and the meat behind them is eaten by arctic foxes, which often follow polar bears. During the day the bear passes and swims long distancesin search of prey. He can spend several hours at the hole, waiting for the next seal.
With the advent of global warming, the climate is changing, glaciers are receding, and polar bears have to travel thousands of kilometers in search of seal habitats. And during the summer, when it gets warm, bears can fast for up to four months.. At this time, they lie peacefully on the shore and bask in the sun.
The polar bear is one of the largest predators on the planet and a real mystery of nature. We will tell you when it appeared, why it is white, and why it is considered a marine mammal.
Mystery of origin
The origin of polar bears is still a mystery to scientists. It was previously believed that polar bears separated from brown bears about 45 thousand years ago, somewhere on the shores of Ireland.
The closeness of the species was confirmed, among other things, by the possibility of the appearance of fertile offspring as a result of crossing, which rarely happens if the parents are “distant relatives.”
In 2011, scientists, based on genetic research, pushed back the date of the appearance of the polar bear by one hundred thousand years ago. Then zoologists, under the leadership of Frank Huyler, reported that the ancestor of polar bears was a certain brown bear who lived about 150 thousand years ago in the late Pleistocene. Moreover, according to the results of the study, the species formed quite quickly, which was explained by the next cold snap and the need to survive in Arctic conditions.
But a year later, a group of researchers from the German Research Center for Biodiversity and Climate (BiK-F) refuted all previous versions. After analyzing the nuclear DNA of 45 not only white, but also brown and black bears (baribals), they found that brown and polar bears once separated from a common ancestor, Ursus etruscus. So, the polar bear is not a “modification” of the brown one, but its brother. According to this theory, the polar bear appeared 600 thousand years ago, which means it emerged victorious from several ice and inter-ice periods. True, this version also has many opponents, and the question of the origin of polar bears still remains open.
Hibernation is not a habit
Polar bears, unlike their brown counterparts, do not hibernate. In winter they sleep more than in summer, but still this is not hibernation. During the latter, the body’s vital activity practically stops: the heart beats weakly, body temperature decreases. Polar bears' breathing and temperature remain normal no matter how long they sleep. In good weather, they often leave the den to hunt seals on the ice - inaccessible prey in warm seasons.
The situation is different with pregnant females. Polar bear cubs, which are born in the middle of winter, are no larger than humans at birth, and they cannot survive the Arctic winter. Therefore, the female lies in a den when the ice melts and hunting becomes difficult. Cubs are usually born in November-January, and remain in the den until February-March. Males and single females hibernate for a short period of time and not every year.
White color – salvation from the cold
Studying the life of polar bears, you involuntarily sympathize with them - how can one possibly live in such conditions, where the temperature can drop to -70 degrees. However, polar bears themselves usually have problems not with freezing, but with overheating. Especially while running. And all this is due to the physiological characteristics of the bear, which are responsible for maintaining heat.
One of the main secrets of polar clubfoot is its white color. It's all about one of the main methods of heat transfer - infrared radiation, which is scattered between numerous layers of fluff or light-colored fur and slows down cooling. According to the researchers, this blocking of thermal transfer, formed during the process of evolution among the inhabitants of the polar regions, provides effective thermal insulation. This is why polar bears are white - they are warmer.
Marine mammals
The scientific name of the polar bear is Ursus maritimus, that is, “sea bear.” Polar bears are excellent swimmers; they can swim hundreds of kilometers without stopping at an average speed of 10 km/h, which is much faster than their leisurely and measured pace on land. The record polar bear swim was recorded in 2011, when a female bear covered 687 kilometers in 9 days without stopping in search of food. These animals spend so much time in the water that some classifications classify them as marine mammals, along with whales, seals and otters.
Prison for bears
The polar bear's main enemy is man. But for our “kind”, an encounter with the largest mammalian predator on earth often ends in tragedy. In recent decades, polar bears have become frequent visitors to cities in the Arctic Circle. They are attracted to “easy prey” - garbage, pets. Thus, in the vicinity of the Canadian city of Churchill, up to 1000 individuals can roam in the summer. Previously, animals were shot, today the death penalty has been replaced by imprisonment - a prison was built on the site of a former military base for troublemakers.
The term of imprisonment usually ranges from two to 30 days, but in the case of repeated catching of the same bear, the term is increased. The prison diet is quite strict - the animals are given only water. The essence of the method is to develop a feeling of fear in animals when approaching the city. The “criminals” are released closer to winter, when ice appears in the waters of Hudson Bay, and with it, hunting becomes easier.
At risk
Polar bears today are an endangered species. And it’s not even about poachers, but about climate change. According to Canadian biologist Ian Stirling, "Ice break-up in Hudson Bay is about two weeks earlier than it was twenty years ago." This deprives bears of the opportunity to gain the necessary fat reserves before the warm months, when all hunting comes to a standstill. The main prey of polar bears is seals and their cubs, which they usually take out from under the ice when the prey swims up to the hole to “sip” oxygen. In open water, clubfoot has no chance.
Therefore, along with warming and melting glaciers, the population of polar bears is also decreasing. According to researchers, since 1980, the birth rate and average weight of these animals have decreased by about ten percent. In search of food, they have to travel greater and greater distances. For example, the above-mentioned nine-day record swim of a female bear, 687 kilometers long, was caused precisely by the need to find food for her and her one-year-old cub. The latter was unable to cope with such a grueling voyage. According to preliminary forecasts, if the ice cover continues to shrink at the same rate, by the end of the century polar bears will repeat the fate of their extinct relatives.
Probably, each of us has seen the cartoon about Umka, and for many it has been their favorite since childhood. Lots and lots of snow, polar lights, ice holes filled with silvery fish, a big and infinitely kind bear, and with her a tiny and so funny bear cub who is just learning about the world. Have you ever thought about where polar bears live in the real world, not in a fairy-tale world, what they eat, whether they hibernate, how often a female bear gives birth?
Where do polar bears live: general information about the animal
The northern brother of the brown bear can boast of a powerful physique: an average, approximately 700 kg in weight, representative of this class reaches one and a half meters in height and three in length. He has thick, short, but very strong legs with wide feet. By the way, the latter are much longer than those of their relatives. They provide the animal with more comfortable swimming and movement when walking on ice or snow. But that's not all. The paws end in short toes with long, thickened and curved claws. The fingers are connected to each other by a fairly thick membrane. Have you ever read that a polar bear does not slide on ice? Why? Nature itself took care of this: the skin and hair on the paws guarantee traction on uneven surfaces. The animal's fur is thick, shaggy and very long, so it is not afraid of low temperatures either under water or on land. In areas that require more protection from the cold, namely on the neck, back, back of the belly, legs and feet, the coat is thicker and longer. By the way, the change of seasons does not affect the color of the fur coat in any way. The polar bear is always milky yellow or snow-white. Both males and females must hunt almost around the clock to feed themselves, without hibernating. A pregnant bear takes refuge for some time in a thoroughly dug den, from which in the spring she emerges with one or more often two cubs.
There is a fairly widespread belief that the polar bear can live wherever there is snow. It's a delusion. I will probably surprise many now by saying that this species of animal can only be found on the shores of the Arctic Ocean. They have never lived in Antarctica, although there is no less snow there, there is enough food, and comfortable climatic conditions persist throughout the year. As you can see, the polar bear (photos above and below) cannot help but touch you. It seems that a kinder creature simply does not exist. But nevertheless, it is considered a dangerous predator, which has excellently developed not only smell and vision, but also all other senses. A bear can smell a potential victim several kilometers away. The bear is very curious; one might say, he is attracted to everything new and unknown, and each item will definitely be tested for taste. This giant is known as a real gourmet. Hunting mainly in water, he, of course, does not disdain any living creatures, however, when he gets out on land, he strives to destroy bird nests, and with great pleasure feasts on both the eggs of polar birds and chicks.
Where do polar bears live: debunking myths
Probably, in films or cartoons, each of us has seen how penguins and bears live side by side on the icy coast. In reality, this cannot be. Some live at the North Pole, others only at the South Pole. That is why it is possible for them to meet only in an artificially created environment, for example, in a zoo. This arctic mammal, thanks to its impressive physique, has no enemies, so it is not afraid of any other animals. By the way, polar bear meat is unsuitable for food.