Polar bears are some of the fascinating creatures in the world. Not only because they’re the only bears that are white and live in the snow, but also because of their adaptations. Polar bear adaptations have been a point of research and discussion for decades, and rightly so. From hibernation to eating fat only, there’s a lot to learn about polar bears.
In this guide, let’s talk about the major polar bear adaptations.
What Are Polar Bears?
Wait! If you think the polar bear is just a bear that’s white and lives in snowy areas, you’re wrong. Polar bears are the largest bears in the world, and they are one of the top predators in the Arctic. Though all bears are carnivores, most bears are omnivores. They also eat plants. Polar bears, on the other hand, are strictly carnivores.
Polar bears are also great swimmers. They can swim clock an impressive six miles an hour while paddling through the water. Let’s look at some ways polar bears are different from other bears.
- Polar bears have a snow-white coat, opposed to the silvery-brown fur of other bears.
- Polar bears are larger than almost all subspecies of bears.
- They have larger feet and soft papillae to help them swim and walk on snow.
- Polar bears have longer skulls than other brown bears.
- Polar bears have smaller claws.
- They are not territorial, whereas brown bears are.
- Polar bears are diurnal, while brown bears are nocturnal.
Characteristics and Facts about Polar Bears
Before delving into polar bear adaptations, let’s look at some characteristics of polar bears you must know about.
- Adult male polar bears can weigh up to 700 kg, while females can weigh 350 kg.
- They can be up to 2.5m long.
- The breeding season for polar bears is between November and February.
- The estimated population of polar bears worldwide is between 20,000 and 25,000.
- Polar bears primarily feed on seals resting on the sea ice. However, they can also eat roots and seaweed if the situation demands it.
- There are 19 recognized species of polar bears, all located within the Arctic circle.
- As of now, polar bears have no predators apart from humans.
Polar Bear Adaptations You Didn’t Know
Most people know that polar bears hibernate. They eat large amounts of food during summer, and when the long winter arrives, they find a warm place and spend months sleeping to conserve energy. However, that is only one of many polar bear adaptations.
Let’s look at a list of adaptations polar bears make to survive in the harsh cold of the Arctic.
Polar Bear Adaptations: Low Surface Area to Volume Ratio
Polar bears have a surprisingly low surface area to volume ratio. They have shorter legs, small extremities, and a large, stockier build. Hence, they don’t lose much heat to the surface area. Many animals that live in colder climates have this characteristic, as it helps them conserve heat in colder climates. On the downside, however, this makes it difficult for these animals to cope with warmer temperatures, as they can easily overheat.
Polar Bear Adaptations: Excessive Consumption of Fat and Not Protein
One of the key adaptations of polar bears, along with hibernation, is they consume high amounts of fat. Polar bears mainly feed on seals, as discussed above. The blubber of the seals is rich in fat and contains the most energy. Most other animals can’t digest so much fat in their diet. However, polar bears are physiologically adapted to eat and digest fat-rich blubber.
Polar Bear Adaptations: Little or No Consumption of Protein
Another adaptation along the lines of excessive fat consumption is minimal protein intake. If they eat protein, they’ll need to excrete nitrogen in proteins. Removal of nitrogen from the body requires the excretion of urea with urine. Polar bears don’t urinate much because the availability of drinkable water on the poles is scarce. They can’t simply eat snow to replace the lost water. Not eating protein is a simple solution to this problem.
Note: Consuming too much fat can cause digestion problems in humans. Follow this article to learn about easily digesting foods.
Polar Bear Adaptations: Thick Layer of Blubber
Polar bears eat the blubber of other sea mammals to form their own blubber. As funny as it may sound, a polar bear’s fat layer can be up to 10 cm thick. Blubber has two functions:
- It acts as an insulator and protects the polar bear from the external cold.
- It acts as food storage. When polar bears undergo hibernation, they try to accumulate as much blubber as possible. In fact, up to 50% of a polar bear’s body weight can be fat.
Polar Bear Adaptations: Getting Metabolic Water by Processing Body Fat
As discussed, drinkable water in the Arctic is scarce. Polar bears fulfill their water requirements by turning fat into metabolic water. The fat in their bodies combines with oxygen to release metabolic water and carbon dioxide. Hence, they get access to freshwater without searching for water. Camels do the same thing to get fresh water in deserts.
Maternity Dens
Pregnant polar bears don’t give birth to baby polar bears in the open. They’re too weak and cannot survive the extreme cold of the Arctic. Pregnant females dig up dens to give birth to their offspring. They dig a few chambers that provide protection against cold and winds.
The cubs stay there with their mothers for around 28 months; thereafter, they are strong enough to live their own life. Male polar bears play no role in the upbringing of their children.
Strong Swimming Skills
Polar bears are excellent swimmers, which makes them capable of living and surviving in up to 200 miles of open waters. They can swim long distances. However, swimming is energy-expensive for polar bears. Hence, younger polar bears avoid it or swim for shorter distances only.
Conclusion
Polar bears perform a series of behavioral and physiological adaptations to survive in the brutally cold Arctic environment where food and water are scarce. They eat only fat to preserve urine, use stored body fat to meet their water needs, and create maternity dens in the snow to protect their children.
So, which polar bear adaptation fascinates you the most and why?
