POLAR BEAR AND CLIMATE CHANGE

POLAR BEAR

Polar bears have long been regarded as the poster child for climate change. Polar bears only exist on Arctic sea ice. In contrast with many other animals who seek warmer areas when winter comes, polar bears prosper during winter time. All their physical characteristics have adapted to extremely cold weathers: they have hollow fur which allows them to float when swimming; they have furry feet in order to provide traction and warmth when walking on the ice; they have webbed paws and dense leg bones, allowing them to swim long distances. Therefore, climate change put polar bears to a situation where they hardly adapt themselves to warmer temperature.

Their activities, including shielding, traveling, mating, andhunting, basically rely on sea ice. Therefore, when climate change raises global temperature abnormally, these polar bears’ lives are put in danger. Their situation is even worse than most other creatures since climate change tends to produce a larger change in temperature near the poles than the planetary average. When the weather gets warmer, sea ice begins to melt, decreasing living space for polar bears and many other creatures living there. Not only does living space decrease, but food supply for polar bears also drops. Polar bears’ favorite prey is seals, which depend on stable sea ice to give birth and nurse their babies. Therefore, a shortage of suitable ice leads to much more birth failure. As the seal population drops, many polar bears go ashore to search for food, such as goose eggs, or even trashes. However, food on land is not able to satisfy the daily calorie need of polar bears, and many bears starve to death. One study published in Ecological Applications demonstrated that there has been a 40 percent population drop between 2001 to 2010 in northeast Alaska and the Northwest Territories.