1. Transparent fur
Polar bears appear white, but their fur is actually transparent. It only appears white because it reflects visible light. To humans and other animals who can see only visible light, the bears appear to blend in with their snowy surroundings. But reindeer, who polar bears sometimes prey on, can see ultraviolet light, which makes polar bears stand out from their snowy environment.
2. Big boys
It’s not a good idea to mess with an adult male polar bear, as they can weigh between 351 and 544kg. The largest polar bear ever recorded weighed around 1,000kg! The males are also around double the size of the females, who weigh 50-295kg.
3. Protective environment
Female polar bears give birth to their cubs in snow dens in November or December, where the family is protected from the harsh Arctic environment. At birth, the cubs are only around 30cm long and weigh around half a kilogram – that’s about the same as a guinea pig!
4. Biggest threat
The biggest threat to polar bears is climate change. Rising global temperatures means that their habitat of sea ice is melting earlier and forming later each year, leaving themless time to hunt for food. This is because polar bears use their sea ice home as a platform from which to hunt.
5. Hardy bears
Polar bears are well adapted to survive in one of the harshest environments on our planet. There is a thick layer of fat under their skin called blubber. It protects their bodies from the frosty air and near-freezing water. Polar bears also have black skin under their glistening coat, which helps them soak up the sun’s rays and keep warm.
6. Sticky problem
Oil spills can be very dangerous. A bear with oil on his coat cannot regulate his body temperature properly. If the bear eats the oil while grooming he could die. Other forms of man-made pollution are also a cause of death. At each stage of the food chain, pollutants get more concentrated.As top predator, the polar bear can be exposed to pollutants through their food.
7. Strong and special liver
They have a special liver that allows them to process all of the seal fat they eat. Seals store a lot of vitamin A in their blubber which allows them to survive and grow quickly. A polar bear’s liver contains 10 times more vitamin A than any other animal on earth. Their liver has evolved to allow them to process and eat all of the seal blubber they need to stay alive.
8. Fantastic swimmers
Polar bears can swim up to 161km at a time. They can swim an average of almost 10km/h.Their huge, webbed paws are perfect for swimming through the ocean.
9. Becoming invisible
If you use an infrared camera, the only things that will be visible is the polar bear’s nose, eyes and breath. The radiative properties of polar bear hair are exactly the same as those of snow, allowing the bear to turn invisible under infrared light.
10. Mother bear
Polar bear cubs learn to hunt by watching their mother. Cubs try hunting in their first year, but don’t seem to be successful until they’re over one year old. Even then, they only spend about 4% of their time hunting. By the time they’re two years old they spend about 7% of their time hunting and can catch a seal every five or six days.