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Essay On Polar Bears

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Polar bears are one of the Earth’s largest and most powerful carnivores. These bears are dependent on sea ice as their primary habitat and are thus found on the Arctic coasts of North America. The scientific term used to describe polar bears, Ursus maritimus translates to sea bear because polar bears spend most of their lives on the Arctic ice. A common misconception the public holds is that polar bears are white; their fur is actually consists of two transparent layers: hollow guard hairs and an undercoat. While the two layers appear white because the air spaces in each hair scatter light, they are actually transparent and the black skin underneath the fur is penetrated by sunlight, warming the bears body. Polar bears are the largest of…show more content…
Analyzing polar bears’ life history will help lay a foundation for understanding why they are currently threatened. Currently there are about 22,000-31,000 polar bears found in 19 subpopulations across the globe (Wiig O et al., 2015). Polar bears have a “circumpolar distribution”: they generally live around the Arctic region around the North Pole, relying heavily on the Arctic ice for hunting, mating, resting, and creating dens (Gunderson, 2009). Their geographic range is determined by the level of ice in coastal areas which differs from summer to winter time. For example, during the winter, polar bears are more often seen at the southern edge of the ice pack versus during the winter they tend to stay on islands and coastal regions that retain ice on land. This heavy dependence on the level of sea ice makes them highly susceptible to global…show more content…
Other threats may include oil and gas development, and environmental contaminants, and over hunting (Center for Biological Diversity, 2013). As previously mentioned, polar bears are dependent on the Arctic ice to sleep, mate and eat. Because of the melting ice, polar bears are travelling longer distances to stay with the rapidly dissolving ice. Sometimes, the bears simply stay on land relying on fat stores until it is safe to go back onto the ice once it refreezes. However, this runs the risk of starvation as traditional prey are found in the ocean and not on land. As mentioned before, one of the two threats to polar bears are other polar bears as male bears may prey on cubs in times of starvation. Moreover, as the ice melts, humans take that as a signal that a new ocean has risen and thus there is an opportunity of industrial development. Such development can include petroleum exploration – however, a single oil spill in the Arctic would prove detrimental for not only polar bears but the entire ecosystem below them. As these “new oceans” arise, there has been more human movement and shipping around the Arctic. These ships both disturb the polar bears and also run the risk of environmental contamination. Finally, there are reports of about “800 polar bears killed every year by hunters, mostly in the Canadian Arctic” (Center for Biological
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