CLASS: Mammalia (Mammals)

ORDER: Carnivora

FAMILY: Ursidae

GENUS: Ursus

ABOUT

Baby, it’s cold outside! Polar bears are an enduring symbol of the frozen Arctic tundra. Perfectly adapted to their icy world, they thrive in extreme cold thanks to fascinating biological traits.

Their outer coat consists of long guard hairs that repel water, shielding a dense undercoat that traps warmth. Surprisingly, polar bears’ fur isn’t white but clear and hollow, reflecting light to appear white, cream, or even pink under Arctic hues. Beneath their fur lies a thick layer of-fat—up to 4 inches (10 centimeters) thick—providing insulation, buoyancy, and an energy reserve for food-scarce periods.

Unlike other bears, polar bears don’t hibernate. Only pregnant females den up during winter to give birth, while others endure the harsh weather by seeking temporary shelters in snow. Their lineage reveals that they evolved from brown bears approximately 200,000 years ago, making them the newest of the eight bear species. Standing up to 10 feet (3 meters) tall, male polar bears are truly massive, yet their wide, paw-padded feet give them traction on slippery ice.

When not hunting, polar bears are often resting, sometimes up to 20 hours a day. They craft unique dens—from snow burrows to seaweed nests—where they relax while letting snow provide natural insulation.

HABITAT AND DIET

Dear Lykkers. Polar bears inhabit the Arctic, living on sea ice to hunt seals, their primary food source. Their scientific name, Ursus maritimus, or "sea bear," reflects their swimming prowess. These powerful swimmers can cover over 60 miles (100 kilometers) in search of food, using broad front paws as paddles and hind legs as rudders. However, with shrinking ice, their swims now extend hundreds of miles, depleting their energy reserves.

The ringed seal is their favorite prey, providing enough energy for up to 11 days. While they’ll eat other animals and vegetation, only seals offer the high-calorie diet they require. At zoos, polar bears are fed a specialized diet of meat, fish, and occasional vegetables, which are more treats than staples.

Pregnant females experience an extraordinary adaptation called "winter sleep." In their snow dens, they survive for months without food or water, thanks to their-fat reserves, and give birth to one to three cubs. Cubs are born tiny—weighing about 1 pound (0.45 kilograms)—and grow quickly on their mother’s fat-rich milk.

Polar Bears: Masters Of The Snow | Snow Animals | BBC Earth

Video by BBC Earth

FAMILY LIFE

Polar bears are intelligent and playful creatures. Friendships may form between bears, leading to shared meals and travels. These interactions sometimes include sliding on ice—seemingly just for fun! Generally solitary, polar bears only gather during mating season or while scavenging.

Mating season runs from March to July. Males track females using scent trails in the snow. Fertilized eggs undergo delayed implantation, ensuring cubs are born under favorable conditions. Cubs stay with their mothers for about two years, learning vital survival skills.

AT THE ZOO

The San Diego Zoo’s polar bear habitat, the Conrad Prebys Polar Bear Plunge, offers visitors a unique glimpse into their lives. Guests can watch these Arctic giants swim gracefully underwater or observe them playing on the beach-like tundra. Interactive exhibits highlight their habitat challenges, such as declining sea ice, and inspire conservation efforts.

Polar bears face dire threats from climate change, as melting sea ice disrupts their hunting and habitat. Conservationists work to mitigate these challenges by raising awareness and advocating for policies to combat global warming. As ambassadors of the Arctic, polar bears remind us of the fragility of their ecosystem and the need for collective action to preserve it.