Polar bears are endangered. Scientists believe rising temperatures in recent years are threatening the survival of polar bears because:

Polar bears are the top predator of the icy Arctic. But these large, furry white mammals have to work hard for their food. when the ocean freezes in the winter, polar bears travel hundreds of miles over floating sheets of sea ice to hunt their favorite meal--seals. During this time, they build up fat that will help them survive the rest of the year. when the ice begins to melt, polar bears head back to land, where they stay during the Arctic summer.
Polar bears are endangered. Scientists believe rising temperatures in recent years are threatening the survival of polar bears because:
polar bears overheat in the warmer temperatures
larger predators are migrating north
sea ice is melting earlier
When the ice melts earlier in the year, polar bears have less time to hunt and build up the fat they need to survive in warmer months. And while polar bears can swim dozens of miles when they need to, less ice makes for longer and more tiring swims.
Seals are the polar bear's favorite meal. The most common way the polar bear hunts is by:
waiting on the ice until a seal appears
swimming underwater to catch a seal
chasing a seal once it moves onto land
A polar bear will wait patiently by a hole in the ice. When the seal surfaces to take a breath, the polar bear pulls the seal onto the ice. If a seal is already on the ice, a polar bear may stalk it by land or swim up and surprise it from the ice edge.
Polar bears are poor swimmers because they are so heavy and have such thick fur.
They are powerful swimmers, using their large front paws as paddles and their back paws to steer. Their fur is waterproof. Underwater, their ears lay flat and their nostrils close.
The polar bear's skin is black.
And while you might think its fur is white, these stiff hairs are actually clear and shiny. the hairs look white because they reflect light.
Scientific name: Ursus maritimus
Claim to fame: The largest predator on land
Adaptations for the cold: Two layers of fur and thick layer of blubber
Habitat: Arctic sea ice, water, islands, coastlines
Diet: seals, fish, sea birds, whale carcasses
Size: 700-1700 lbs (males); 500-600 lbs (females)
Lifespan: 15-18 years (in the wild)
<<b>Cool fact: paws have thick black pads covered with tiny bumps that keep them from slipping