© Tim Auer/Polar Bears International
2/20/2019 1:33:32 PM
7 Surprising Polar Bear Facts
Polar bears are amazing creatures, with many unusual characteristics. With International Polar Bear Day one week away, on February 27th, we're counting down the days with a week's worth of polar bear facts. Test your polar bear knowledge and see if you can choose a favorite!
1. Just like whales, seals, and dolphins, polar bears are considered marine mammals.
A bear that’s not land- bound? It’s both surprising and true! Polar bears are the only species of bear that depends on the ocean ecosystem to survive. Their life is tied to the sea ice and to the abundant world that blooms, swims, and paddles beneath their paws. This fun fact is even hidden in their scientific name–––Ursus maritimus means “sea bear.”
2. The great white bear of the North is not actually white.
So how do they look white? Each hair shaft is pigment-free and transparent with a hollow core that scatters and reflects visible light, much like what happens with ice and snow. Polar bears look their whitest when they are clean and in high-angle sunlight, especially just after the molt period in spring/summer. Before molting, oil build up in their fur from snacking on seals can make them look yellow.
3. Polar bears are big fans of the snow bath.
When a polar bear’s coat gets dirty––for example after a meal––they rub and roll their body across the snow to clean their fur. Polar bears like to be clean and dry because matted, dirty, and wet fur is a poor insulator. And in Arctic extremes, insulation is key!
4. Polar bear paws are expertly designed for traversing the slick and shifting sea-scape.
A polar bear’s paws measure up to 30 centimeters (11.81 inches) across, to help polar bears tread on thin ice. When the ice is very thin, the bears extend their legs far apart and lower their bodies to distribute their weight. Black footpads on the bottom of each polar bear paw are covered by small, soft bumps known as papillae. Papillae grip the ice and keep the bear from slipping. Tufts of fur between its toes and footpads can help with security as well.
5. Polar bears touch noses to ask to share food.
A polar bear asks another bear for something, such as food, through a nose-to-nose greeting. The guest bear will approach slowly, circle around a carcass, then delicately touch the feeding bear’s nose to ask for permission to share.
6. Unlike other large carnivores, polar bears do not have territories; they have home ranges.
The sea ice habitat of polar bears is variable in almost every way (prey distribution, freeze up and break up patterns, etc.)–––this lack of predictability removes the potential benefit of defending any sort of territory. Unlike a territory, home ranges are not defended so individual polar bear home ranges overlap with other bears. Current scientific findings show that a polar bear’s home range size can vary over 2000-fold in the same population. Some bears live in a single fjord while others wander areas the size of Texas!
7. Polar bears don’t prefer sea ice to land, they NEED sea ice to survive.
A polar bear’s hunting and eating patterns depend completely on sea ice. Why? Because seals depend on it––and seals are the only food source with a high enough fat content and enough calories to keep a polar bear healthy. Polar bears can only reach seals from the platform of sea ice. While they are good swimmers, catching a seal in open water is extremely challenging and unlikely. Polar bears also rely on sea ice for traveling, breeding, and sometimes denning.