Polar Bear
Polar Bear Facts
| Size | 78 to 98 in (200-250 cm) (body) |
| Speed | Up to 25 mph (40 km/h) (on land); 3 mph (5km/h) (in water) |
| Weight | 880 to 1,100 lbs (400-500 kg) |
| Lifespan | 20-30 years |
| Food | Seals, salmon, lemmings |
| Predators | Orca, walrus |
| Distribution | Arctic region |
| Habitat | Pack ice, drift ice, ocean |
| Order | Carnivore |
| Family | Bears |
| Scientific name | Ursus maritimus |
| Characteristics | Large predator with white fur and webbed feet |
Main Characteristics
The polar bear is a predator and one of the largest bears in the world. Only the Kodiak bear (a brown bear subspecies) from Alaska reaches a similar size. Its most eye-catching characteristics are the transparent fur, the thick layer of fat, the small round ears, the long claws, the large paws and the webbed toes.
Distribution and Habitat
Polar bears live exclusively in the Arctic (= around the North Pole). 60% of polar bears live in northern Canada. The other 40% are spread across Alaska, Greenland, Russia and Svalbard. There are no polar bears in Antarctica (= at the South Pole).
Life Style
Polar bears are solitary animals that are active during the day. They spend most of their time wandering, resting or sleeping. They overheat easily, so they usually move very slowly and roll in the snow or dive to cool down.
Anatomy and Appearance
Size and Weight
Polar bears weigh between 880 and 1,100 pounds (400 and 500 kg). Their body length is between 78 to 98 inches (200-250 cm) and the shoulder height is 62 inches (160 cm).
Fur
Although the fur of the polar bear appears to be white, its hairs are actually transparent and hollow inside. There is a good reason for this: The warmth of the sunlight can directly reach the skin. To clean its fur, it simply wallow in the snow.
Skin
Surprise! The skin under their fur is black. The reason is that black holds onto heat the most effectively.
Fat Layer
Polar bears have a thick layer of fat that keeps them warm in the Arctic. It grows up to 4 inches (10 cm) thick.
Paws
Polar bears have large paws, with the front ones being shovel-shaped, used for setting the pace, while steering is done with the hind paws. The paws measure around 11 to 12 inches (30 cm) in length. This also is a major advantage when walking: The weight of the polar bear is evenly distributed, preventing it from sinking in the snow or breaking through thin ice.
Webbed Toes
Its toes are webbed to move faster in the water.
Claws
Polar bears have sharp claws that are up to 2 inches (5 cm) long. They help them hold on to slippery ice floes.
Size Comparisons
• Polar Bear vs. Small Car
How big is a polar bear actually? We went looking for an everyday object that might help you imagine it better. It is about the same size as a very famous and popular Italian car: the Fiat 500. The Smart from Mercedes is also similar in size.
• Polar Bear vs. Brown Bear
Polar bears are usually larger and heavier than brown bears. Even large grizzly bears are smaller and lighter. An exception is the Kodiak bear, which is a subspecies of the polar bear, too. It can weigh a little more than a polar bear. That's why they're considered the largest bears in the world.
Diet
Polar bears are carnivores. They feed mainly on seals. However, they also prey on weak walruses and small rodents such as lemmings, voles and ground squirrels. Sometimes they also hunt fish. Polar bears don't eat penguins. Do you know why? Polar bears live in the Arctic. Penguins live in Antarctica.
Behavior
Swimming
The record for the longest distance a polar bear swam is 426 miles (687 km) in nine days. It swam 232 hours non-stop. This was reported by the United States Geological Survey (USGS) in Polar Biology magazine in 2008. Usually the animals do not swim such long distances because it is very exhausting for them. However, this is happening more and more due to climate change.
Diving
Polar bears are good swimmers, but they can only stay underwater for about 2 minutes. Then they have to surface again to catch their breath. They usually don't dive deeper than 6 to 7 feet (2 m).
Hunting Strategies
Polar bears don't hunt in water. Instead, they wait at ice holes until seals resurface to breathe. Then they strike. Sometimes they wait for hours for a seal to appear. Another hunting technique is stalking. The polar bears crouches and then creeps the last few feet over the ice. Then they suddenly rush to grab their prey.
Do Polar Bears Sweat?
In the Arctic, temperatures range from -58 degrees Fahrenheit (-50 degrees Celsius) in winter to 68 degrees Fahrenheit (20 degrees Celsius) in summer. During the winter, the fur keeps the bear warm. Yet, during the Arctic summer, the animals often get too warm. To cool down, they lie down in the snow or on the ice on their backs and lift their feet up in the air. Even after short distances, they are often seen to lie down. Sometimes they even jump into the icy (!) waters to refresh themselves.
What Do Polar Bears Do in Winter?
Between October and February there is almost total darkness in the Arctic. However, the animals don't hibernate. Seals are plentiful, so they spend a lot of time hunting and feeding. Only pregnant females rest and stay in a cave during the winter.
Are Polar Bears Dangerous?
Polar bears are very large, heavy and powerful predators. When they're hungry and can't find any food, or feel threatened, they can also be very dangerous to humans. Since polar bears live in the Arctic, encounters are rare. If climate change continues to impact the environment, polar bears may be forced to move closer to human populations in the south. This could lead to potential conflicts between humans and polar bears as they search for new habitats.
Senses and Abilities
Senses
Polar bears have an amazing sense of smell. They can smell seals up to one mile away. They also have very good hearing and a very good sense of sight.
Adaptation to the Habitat
How do polar bears survive in the Arctic? Here are the five most important adaptations to their habitat:
- 1. Two layers of fur
- 2. Black skin
- 3. A thick layer of fat
- 4. Excellent sense of smell
- 5. Sharp claws
Enemies and Threats
Natural Predators
Polar bears are so-called apex predators (from the Latin “praedator” for “hunter”). They're right at the top of the food chain. Nevertheless, there are other predators that sometimes prey on weak, sick or old polar bears. For example, orcas. They were observed tipping polar bears off ice floes. Walruses can also kill a polar bear with their large tusks. However, they don't kill the bear for food, but rather to protect themselves or their food.
Why Are Polar Bears Threatened With Extinction?
Polar bears need pack ice on which they can rest, hunt, eat and reproduce. After all, they're not marine mammals that spend all day in the water. Unfortunately, due to climate change, the pack ice is melting, so they have to migrate further and further south to the mainland. However, they normally hunt seals and are less successful at hunting on the mainland. This is why experts estimate that polar bears will be extinct by the year 2100 – or sooner.
Reproduction
After mating, it takes around eight months for the cubs to be born. About a month before giving birth, the female polar bear digs a cave in which she gives birth to two to four cubs. They're blind and deaf when they're born and they only weigh 14-30 ounces (400-900 grams). Thanks to the high-fat mother's milk, they weigh 22-33 pounds (10-15 kg) after just two months. At this point the young animals are allowed outside for the first time. The mother continues to nurse them until they're 2.5 years old. During this time, the mother also teaches them how to hunt.
Cross Breeds
Climate change is causing polar bears to move further south, where they are interbreeding with brown bears. This is possible because their genetic composition is quite similar, resulting in offspring that can also reproduce. Such a cross breed is called pizzly bear, grolar bear or brolar bear. “Pizzly” and “grolar” are made up of “polar” and “grizzly”. “Brolar” is a mix of “brown” and “polar”.
Fun Facts
All polar bears are "left-pawed".
The Polar Bear Is Related To:
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