Polar Bears and Possibility of Extinction
Yasmine Bazan
Polar bears are large bears with strong legs and flattened feet with webbing that help walking on ice and swimming. Polar bears evolved about one to three million years ago from the brown or grizzly bears. Polar bears have adapted to live in the cold so they could maintain their body heat and deal with their freezing habitat. Polar bear’s outer layer of fur is hollow and reflects the light giving their fur a white color, which helps the bears to stay camouflaged in their icy habitat. Their skin is also black under their fur; however, it can only be seen on their nose. The bear’s footpads on their paws prevent them from slippering over the ice. The bears also have a thick layer of fat below the surface of the skin, which acts as an insulator and traps heat. This is imperative particularly while swimming and during the winter weather. Large-sized polar bears contain high body mass, which help in generating more heat. Polar bears are the largest land mammals on Earth. They are almost exclusively meat eaters. They eat ringed seals, bearded seals, walruses, and other species of seals and whale remains. However, they mainly eat ringed seals. Polar bears will also look for bird eggs and other sources of food but those are not enough to withstand their large body mass and large populations.
We know that polar bears hunt seals. However, how? They wait for the seals to come to the surface of the sea ice to breathe and when the seals are near the surface, the polar bears will grab or bite the seal and tug it onto the land so they could eat. Another important food source is the seal pup that is born and that lives in dens in the arctic ice. The polar bears identify these dens by smell and jumps through the roof to capture the young seals.
Polar bears are in grave danger of becoming extinct and surveys show that two-thirds of the polar bears will disappear by the year 2050. The main reason for that is global warming as it continues to melt the Arctic’s sea ice. The US Endangered Species Act listed polar bears in 2008 because of the ongoing loss of their habitat: the arctic sea ice where they live and depend to hunt seals. Elevating temperatures in the world’s oceans are causing sea ice to vanish for longer and longer periods during the summer leaving polar bears insufficient time to hunt, which is an obstacle since they depend on the sea ice where they hunt down seals.