Polar bears are affected badly because of global warming.Even more so because they live at the poles of the Earth, so as the polar ice caps melt, their food supply goes down. Scientists predict that if the polar ice caps melt at this rate, two-thirds of the polar bears we have now, are going to be extinct within this century. But, polar bears aren't lost just like that, we can prevent it, if only we could reduse greenhouse gas emmisions, and climate change caused by humans, polar bears still stand a chance. BUt that is not all of the reasons why polar bears are in danger of extinction, polar bears were also hunted, but then that was banned, but not soon enough, because some were already hunted down. Also, because the polar ice caps are melting, the seals are not staying with the polar bears, so naturally, the bears will have to go hungry. When they are hungry, it is only natural for them to look for food, which is most definitly going to make them swim longer and more, and that would use up more of their already low fat reserves. If they don't find any food, of course they will come onto land to look for other replacements for seals, and as they come onto land, their life is in even greater peril than it was when they were living on the quickly melting ice, because they are amongst humans.