On this occasion, from our site we want to present you with an article about a great terrestrial predator, in fact the main one in the Arctic zone. We refer to the polar bear (Ursus maritimus). These ursids are animals that have particular characteristics that allow them to thrive in the northern polar area of regions such as Canada (where the largest population of the species is located), Alaska, Russia, Greenland and Norway.
Polar bears are quite attractive, not only because they inhabit regions with extreme environmental conditions, but also because of their striking white color and size. This last aspect is a fundamental trait to be able to feed and survive in the Arctic, so if you have ever wondered how much a polar bear weighs, we invite you to continue reading and thus know the answer.
Physical characteristics of a polar bear
The polar bear's head is longer and narrower than that of the rest of its relatives, as well as its ears and nose, which are also small and black, which limits heat loss. The fur of these animals is made up of thousands of hollow, translucent individual hairs that, by reflecting the sun's rays, make the animal's color appear white. This peculiarity of hollow hairs allows them to be filled with air, which also functions as a thermal insulating layer Underneath this thick coat is the skin, which It is black, facilitating the attraction of solar rays and, therefore, the increase in body temperature.
Usually in the summer, polar bears lose some of their fur due to molting. At birth, the new coat is perceived as a particularly intense white. Eventually, and especially in spring, you can see a more yellowish color due to the action of the sun's rays at the time. Without a doubt, the white color observed in these animals can be considered an adaptation that facilitates camouflage in the ice caps when hunting.
The characteristic development of their legs allows them to swim, an action they perform with great skill. The front ones are slightly curved, with thick and pointed claws, optimal for hunting and moving with agility on the ice sheets.
Polar bears have a thick layer of fat that is only reduced towards the snout, which they accumulate thanks to their specialized diet. This adipose tissue is essential for these animals to live in the particular ecosystem where they live. The fat cover is reduced in the summer months, since at this time there is less ice, so the bear must swim to go after the prey and this implies a higher caloric expenditure than if it did it from the ice sheets, a fact that actually occurs during the seal hunt this season.
How much does a polar bear cub weigh?
Polar bears are late sexually mature and their reproductive rate is among the lowest of any mammal. The females mature at 4-5 years and come into heat between the end of March and the beginning of June, mating usually occurring in April and May. However, a peculiar aspect occurs in this species: ovulation is induced after copulation, so a late implantation occurs, which is consolidated approximately until autumn.
During pregnancy, the females stop feeding and take refuge in burrows that they build for this purpose, but previously they must have gained considerable weight to have sufficient reserves during this time.
Polar bears often have births of twins, although they can also give birth to single litters or triplets. When the pups are born, they are blind, with very little hair, having an average weight of 600 g, which is quite small compared to what they will have when they are adults. However, thanks to breast milk, which contains more than 30% fat and other nutrients, newborns begin to grow rapidly. When they emerge from the burrow, at approximately five months, They already weigh between 10 and 12 kg, so they can follow their mother, with whom they will stay for about two years.
How much does an adult polar bear weigh?
Polar bears are carnivorous animals. In fact, reports indicate that they are the types of bears that consume the most meat. These ursids process fat in a highly efficient way, even better than protein, so to maintain their thick lipid layer and proper he alth they require a high consumption of animals with fat, and this is obtained specifically fromseals, their favorite food Ringed seals (Phoca hispida) are the favorite of polar bears, although to a lesser extent they can also eat bearded seals (Erignathus barbatus), harp seals (Pagophilus groenlandicus) and hooded seals (Cystophora cristata), although they also consume walruses and belugas.
During the time when the ice is reduced and seal hunting decreases considerably, they choose to feed on birds, fish, reindeer and even in a reduced way they can consume certain algae and vegetation. However, none of these foods can offer polar bears the amounts of fat required to maintain their large bodies, as well as the particular requirements to live in the type of frozen habitat in which they live, as we explain in this article. another article on How does the polar bear survive the cold?
This specialized high-fat nutrition makes these animals have large bodies and, therefore, enormous weights. In this sense, an adult polar bear can weigh between 250 and 700 kg This is how these mammals, along with the kodiak bear (Ursus arctos middendorffi), are the largest species of ursids that exist.
Weight of a male polar bear
Male polar bears are considerably large, weighing between 350-700 kg in general, without However, individuals weighing almost 1,000 kg have been recorded. A male can also measure up to 3 meters long
Weight of a female polar bear
Females are usually smaller than males, weighing an average of about 300 kg, although they can weigh a little more. But as we have mentioned, during the gestation and rearing of the puppies in the first months, the females stop feeding, so before taking refuge in the burrows for pregnancy, they feed abundantly, increasing their fat reserves, reaching reach in those moments up to about 500 kg of weight
Polar Bear Conservation Status
Currently, polar bears are classified in vulnerable status on the Red List of Endangered Species by the International Union of the Conservation of Nature. Although hunting of this species has been largely controlled, the current reason for its vulnerability is due to climate change, which is significantly affecting the ice of the Arctic sea. These ursids depend closely on the optimal conditions of their ecosystem, so when they are affected, the impact on the species is really significant, influencing their food sources, as well as affecting the spaces through which they move.
It has also been reported that pollution is another aspect that is disturbing these bears, since significant concentrations of agents have been observed chemicals in their tissues, which alters their hormonal, immune and reproductive systems.
On the other hand, the insistence on oil exploitation in the arctic zone is undoubtedly an action that would cause high negative impacts for these animals and, in general, for the biodiversity of the region.
Finally, we can mention that polar bears are attracted by smells and sounds of human origin, so there is already evidence of fatal outcomes as a result of this approach, caused by the consumption of waste produced by people such as plastics, cans, batteries and other products.
