Global warming, the changing of the Earth’s climate, is happening. This phenomena evidently brought about by anthropogenic activity will cause an average increase in global temperatures, rise in sea level, and the reduction of arctic ice cover, among other effects. As the Earth warms up, the habitable range of the polar bear, which is the reach of the arctic ice, will recede. Polar bears prey on seals that wean pups on the sea ice floats. The fat they receive from hunting these seals is their primary source of energy. They survive on this energy during parts of the year when prey is not available. The arctic ice will shrink and there will be a decrease in the area and amount of time for polar bears to hunt for food. These trends will force polar bears to concentrate their populations towards the poles, or perhaps they may have to adapt to foraging at warmer climates. A recent study has shown that polar bears have increased predations upon bird eggs along the southern border of their habitable range. Populations of polar bears will persist in higher latitudes, but their numbers will decline. If these bears are able to adapt, we may see a crossbreed between adaptable polar bears and northern brown bears
-by Chris Guo
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