Global Warming and the Polar Bear

For many years, the mighty polar bear has captured the attention and hearts of the people. The largest of the world's bear species, with thick white fur and layers of fat to protect against the bitter Arctic cold, may soon be going extinct.

It is not from the hunters wanting their beautiful fur, or from a plague that has struck the wondrous creature, they are in fact, drowning.

According to the National Snow and Ice Data Center at the University of Colorado at Boulder, sea ice is declining at a rate of more than 23,000 square miles per year or almost nine percent each decade.

Living in the Arctic, the polar bears relies on the sea ice for survival. The sea ice is needed as a platform for the polar bear to hunt on, to travel, to scurry about and for making a den area for mating and giving birth.

Sadly the home of this mighty animal is literally melting away due to global warming. Without their sea ice habitat, the polar bear will not be able to survive. As the ice melts around them and their food source diminishes, the polar bear must swim further and further to find ice platforms. During these ever lengthening swims, polar bears are drowning.

With the ice forming later in the fall and breaking up sooner in the spring, the polar bear has little time to forage for food, each year. Scientists have predicted that as the sea ice moves, some bears will drift away into unsuitable habitats, and not be able to return to the main body of ice.

Lower female reproductive rates have been recorded, as well as thinner bears. Cub survival rates are down 43 percent in Alaska's Beaufort Sea and an overall 65 percent since measured in the late 1980s and 1990s.

The U.S. Geological Survey reports that by mid-century, two-thirds of the world's polar bear population could be killed off, due to thinning sea ice caused by global warming. This includes the entire population of polar bears in Alaska.

The temperature in rising faster in the Arctic than in the rest of the world causing the sea ice to quickly melt away. Some climate models predict that by the end of this century, the summer sea ice will be completely melted away. Some scientists believe that the ice could be gone by 2040.

Scientists expect that as the temperature rises, there will be more rainfall during the Arctic's late winter and spring. Out of season rains have already caused dens and shelters to collapse on polar bear mothers and their new born cubs, killing all inside.

The U.S. Fish and Wildlife Service recently proposed listing the polar bear as a threatened species under the Endangered Species Act. The decision will be made whether or not to include Polar Bears on the list in January of 2008.

The polar bear is completely dependent on its habitat for survival, they will become the first mammals in the world to lose 100 percent of their habitat because of global warming.

Three female adult polar bears and one cub were found dead, in the spring of 2006. Two of the females had no fat stores on them, and looked to have starved to death. Scientists predict that by 2012, most female polar bears may not be able to reach the 417 pounds of body mass they need to reproduce successfully.

There have also been some recording of polar bears cannibalizing another bear. On one account it was a female polar bear in her maternal den. This type of behavior has never been observed before, in many many years of polar bears research and observation.

Global warming is increasing due to greenhouse gases, mainly the use of fossil fuels. The United States alone produces 24 percent of global greenhouse gas emissions. Scientist say that the earth will be 3.6 degrees warmer in 2026 than it was in 1750.

WWF expert on sustainable energy, Catarina Cardoso said "If we are to ensure that unique ecosystems like the Arctic are not lost, the G8 meeting must take drastic action to reduce climate change,'' adding that should include a commitment to keeping global average temperatures down.

sources:

http://www.nrdc.org/globalWarming/qthinice.asp

http://www.un.org/works/environment/animalplanet/polarbear.html

http://www.biologicaldiversity.org/swcbd/species/polarbear/index.html

http://www.bearplanet.org/global-warming-polar-bears.shtml