The most serious factor altering polar bears’ habitat is the melting of the sea ice. Polar bears need the sea ice as a platform for hunting their prey, as well as a place to breed. Sea ice is considered as the premier place for polar bears to mate, travel, and migrate (Derocher). Polar bears depend on the sea ice platforms for survival, but with the mounting temperatures produced by global warming, the sea ice now melts earlier in the summer and freezes later in the winter. Scientists are shocked by the rate of sea ice melting in the Arctic Ocean, and they are finding more and more open waters where sea ice originally was. Dates provided by satellite passive microwave sensors have shown that from 1979 to 2006, the annual sea ice area has decreased every month of a year. The most serious sea ice reduction occured in every September, about 9% per decade, which caused the Arctic Ocean to lose about one hundred thousand square kilometers of sea ice (Vongraven, Peacock 15). Furthermore, Derocher indicates that polar ice caps are shrinking steadily which causes more difficulty in getting to and hunting prey (“Polar”). These records prove polar bears’ ability to survive is being obviously threatened.
The most serious factor altering polar bears’ habitat is the melting of the sea ice. Polar bears need the sea ice as a platform for hunting their prey, as well as a place to breed. Sea ice is considered as the premier place for polar bears to mate, travel, and migrate (Derocher). Polar bears depend on the sea ice platforms for survival, but with the mounting temperatures produced by global warming, the sea ice now melts earlier in the summer and freezes later in the winter. Scientists are shocked by the rate of sea ice melting in the Arctic Ocean, and they are finding more and more open waters where sea ice originally was. Dates provided by satellite passive microwave sensors have shown that from 1979 to 2006, the annual sea ice area has decreased every month of a year. The most serious sea ice reduction occured in every September, about 9% per decade, which caused the Arctic Ocean to lose about one hundred thousand square kilometers of sea ice (Vongraven, Peacock 15). Furthermore, Derocher indicates that polar ice caps are shrinking steadily which causes more difficulty in getting to and hunting prey (“Polar”). These records prove polar bears’ ability to survive is being obviously threatened.
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