Polar Bear

Polar bears hunt ringed and bearded seals, which they can only catch on sea ice. They will also eat other foods like belugas and animal carcasses when they can find them. To stay warm, polar bears need high-calorie foods like seal blubber because it helps them maintain their thick layer of fat. Bears with year-round access to sea ice can hunt whenever they want. However, those in areas where sea ice melts each summer have to spend a lot of time on land. During this time, they mostly fast using their stored fat and look for other food sources.
At the Zoo, the polar bears receive a specialized ground carnivore diet, fish, and bones. They also receive produce like squash and lettuce as enrichment.

The polar bear is found throughout the circumpolar Arctic in the five “polar bear nations” of United States (Alaska), Canada, Russia, Denmark (Greenland), and Norway. The polar bear's southern range is limited by the amount of sea ice that forms in the winter because polar bears prefer to travel on sea ice.

Polar bears live in areas like Arctic sea ice, oceans, islands, and the edges of continents. They like habitats with sea ice that have leads nearby. Leads are openings in the ice that can be channels of water or cracks. These openings may stay ice-free for just a few minutes or for several months, depending on the weather and ocean currents.

Polar bears have a few predators. Male polar bears sometimes hunt cubs, so mother bears with young ones will try to stay away from other bears. In the past, Arctic native peoples have hunted polar bears for their meat and fur.

The largest threat to the polar bear is climate change, as the warmer temperatures and unpredictable weather affect major parts of their lives. The loss of sea ice makes it harder for them to find food, breed, and move around in their habitat. Because there is less sea ice, polar bears have to fast for longer periods and often come into contact with humans as they search for food, even looking in garbage. Increased human activity in the polar bears' home can disrupt their denning habits and lead to more encounters with people.

The polar bear is the largest land predator in the world. Its fur can range from pure white after shedding to a yellowish color due to sunlight or staining from seal oil. Interestingly, polar bear fur isn't actually white; each hair is colorless and transparent with a hollow inside. They have a thick, soft undercoat covered by longer guard hairs. Their skin, nose, and lips are black.

Polar bears have broad front paws that work like paddles, making them great swimmers. The bottom of their paws is covered in fur, which helps keep them warm and provides grip on ice and snow. Their large paws help distribute their weight, preventing them from breaking through thin ice. Underneath their fur, they have a thick layer of fat that keeps them warm and helps them float in water. They have a stocky body and a smaller head compared to other bears, with a long neck that helps them move smoothly in the water.

While polar bears possess a very strong sense of smell, their hearing and vision aren't as sharp. They rely on their nose and sensitive whiskers to explore and understand their surroundings.

A female polar bear usually has her first cubs when she is between four and eight years old, with the most common age being five or six. They have one of the lowest reproductive rates among mammals, typically having around five litters in their lifetime. Mating season occurs in late winter and early spring, but the bear only implants the embryo in early winter. This process is called "delayed implantation." It helps ensure that the female is in good health and that there is enough food available for her and her cubs later on.

To prepare for having cubs, a pregnant polar bear needs to eat a lot during the summer and fall so she can build up fat for the denning period. In the den, she gives birth to cubs that weigh about one pound. She will nurse them until they reach around 20-30 pounds before coming out of the den in March or April, and during this time, she does not eat. Usually, there are two cubs in a litter. When they are born, the cubs are blind, toothless, and covered in soft fur, relying completely on their mother for warmth and food.

Polar bear cubs stay with their mother for about 1.5 to 2.5 years. During this time, they learn how to hunt and survive in the harsh environment of the Arctic.

Polar bears can be very vocal. They will often greet each other using a “chuffing” sound.

Polar bears are solitary, except during breeding, while raising cubs, or when interacting near a food source. They are excellent swimmers and may swim exceptionally long distances in search of food. Sometimes for multiple days and hundreds of miles!