The polar bear or ursus maritimus, also known as the polar bear, is the largest predator that lives in the Arctic. It is a carnivorous mammal in the bear family and is arguably the largest land carnivore on planet Earth.
Despite the obvious physical differences with the brown bear, the truth is that they share major genetic traits that would allow, in a hypothetical case, reproduction and fertile offspring of the two specimens. Despite this, we must emphasize that they are different species, whether due to morphological, metabolic or social behavior differences.
The ancestor of the polar bear was the ursus maritimus tyrannus, a very large subspecies.
Origin
- America
- Asia
- Canada
- Denmark
- United States
- Norway
- Russia
Where does the polar bear live?
The polar bear's natural habitat is the permanent sea ice of the polar ice cap and the icy waters surrounding the icebergs and broken plains of the Arctic sea ice. There are six specific polar bear populations on the planet, which are as follows:
- Community of Western Alaska and Wrangel Island, both belonging to Russia
- Northern Alaska
- In Canada, there are 60% of the total number of polar bears in the world
- Greenland
- The Svalbard archipelago, belonging to Norway
- Francis Joseph Land or Fritjof Nansen Archipelago, also part of Russia
- Siberia
Physical appearance
The polar bear, along with the Kodiak bear, is the largest bear species. The weight of the male polar bear can reach and even exceed 500 kg, since we are talking about specimens that have reached more than 1000 kg. Females weigh just over half the weight of males and can reach 2 meters in length. The height of the male polar bear reaches 2.60 meters.
The structure of the polar bear, despite its large size, is thinner than that of its related species, the brown bear and the black bear.
Its head is much smaller and tapers towards the muzzle than other bear breeds. It has tiny, jet-black eyes, and a sensitive snout with enormous scent power. The ears are small, hairy and very rounded.
This very particular facial configuration is due to a double reason: the camouflage and the possibility of avoiding as much as possible the loss of body heat by the facial organs.
The enormous body of the polar bear merges, thanks to the blanket of snow which covers it entirely, with the surrounding ice which constitutes its habitat, and consequently its hunting territory. Thanks to this perfect camouflage, it sneaks through the ice to get as close as possible to ringed seals, which are its most frequent prey.
Under its skin, the polar bear has a thick layer of fat that perfectly insulates it from the ice and icy arctic waters where it swims and hunts.
The legs of the polar bear are much more developed than those of other ursids, because it evolved to walk for many kilometers on the vast northern pack ice and to swim great distances.
Food
The polar bear feeds mainly on young ringed seals; its prey is hunted indiscriminately on the ice, or exceptionally underwater.
The polar bear has two typical ways of hunting: getting as close as possible, with its body glued to the ground, to a seal resting on the ice, getting up suddenly and after a short run, delivering a sharp blow on the seal's skull, eventually biting its neck.
The other method of hunting, and the most common, is to crouch next to a seal's blowhole. These vents consist of holes that seals make in the ice to cyclically exit to breathe during their fishing forays into the waters covered by the ice sheet. When the seal sticks its nose out of the water to breathe, the bear gives it a brutal kick that smashes the skull of the prey. With this technique, he also hunts belugas (marine cetaceans related to dolphins).
The polar bear also detects baby seals hidden in tunnels dug under the ice. When they locate their exact position by smell, they throw themselves with all their might against the frozen ceiling of the den where the baby is hidden, falling on top of it. During the summer, they also hunt reindeer and caribou, or even birds and their eggs in nesting areas.
Behaviour
The polar bear does not hibernate, unlike its congeners. Polar bears accumulate fat during the winter and lose it during the summer in order to cool off. During the breeding period, females do not ingest food and lose up to half their weight.
Between the months of April and May is the only period when females tolerate males because they are in heat. Outside of this period, the behavior between the two sexes is hostile. Did you know ? Some male polar bears are cannibalistic and eat cubs or other bears.
The endangered polar bear
Unfortunately, the polar bear is in grave danger of extinction due to human activity and the system we live in which prioritizes the well-being and economic growth of big business and the privileged few on life itself. After evolving for more than 4 million years, it is now estimated that the species could become extinct by the middle of the century. Oil drilling and global warming seriously threaten these magnificent animals, whose only predator is man.
The main problem the polar bear is currently facing is the effect of global warming on its ecosystem. The gradual increase in the temperature of the Arctic Ocean leads to a more accelerated melting of the Arctic sea ice which is the hunting ground of the polar bear. This premature melting is the reason bears are unable to build up the fat stores necessary for a proper transition from season to season.This fact influences the fertility of the species, which recently decreased by 15%.
Another problem, mentioned above, is the drilling of oil, which destroys its environment, because the Arctic is an area rich in this polluting limited resource.
These two serious problems are pushing polar bears to make increasingly frequent incursions into areas inhabited by humans to feed on the waste produced by their inhabitants. It is tragic that a being as majestic as this super-predator is forced by the harmful action of Man on Nature to survive in this humiliating way. Faced with this situation, only collective action by the whole society (not just individual actions) could change the situation.
Curiosities
- Polar bears don't really have white fur, it's actually translucent and the optical effect makes them look snow white in winter, and more ivory white in summer.These bristles are hollow and filled with air inside, giving enormous thermal insulation ideal for living in the harsh arctic climate.
- The polar bear's skin is black, so it absorbs solar radiation better.
- The polar bear does not drink water because the water around it is s alty and acidic. Polar bears obtain the fluids they require from the blood of their prey.
- The life expectancy of the polar bear is between 30 and 40 years.
Pictures of Polar Bear
