Study: Two-thirds of polar bears threatened

by William Neikirk

Two-thirds of the world's polar bear population could be wiped out by the mid-21st century because of changes of sea-ice conditions, the U.S. Geological Survey projects in a new study.

As a result of the federal agency's study, the polar bear could soon be listed as a threatened species under the Endangered Species Act. A final decision on that designation is due in January.

A scientific team investigating the future of polar bears and their habits took six months to analyze the direct relationship between the presence of Arctic sea ice and the health of polar bears, according to the USGS. The bears "depend on sea ice as a platform to hunt for seals, their primary food," according to the agency.

But global warming is causing a loss of sea ice. Models used by the team of scientists, from the USGS, other American and Canadian agencies, academia and the private sector, projected a 42 percent loss of "optimal polar bear habit from the Polar Basin during summer" by the middle of the century.

If these sea-ice conditions are realized, then two-thirds of polar bears could be gone by 2050, they said. Reductions in the population occur in spring and summer, when the sea ice retreats.

"Because the observed trajectory of Arctic sea ice decline appears to be underestimated by currently available models, this assessment of future polar bear status may be conservative," the report said.

The Fish and Wildlife Service proposed putting the polar bear on the endangered species list last December, prompting Interior Secretary Dirk Kempthorne to request a USGS scientific survey to help him make a decision by January.

The global warming debate has become deeply embedded in U.S. politics. After release of the information, Rep. Edward Markey (D-Mass.), chairman of the Select Committee on Energy Independence and Global Warming, said in a statement:

"This is becoming a tragic metaphor for the administration's voluntary approach to global warming--instead of meeting the challenge, the Bush administration is happy to float along, waiting to see if the planet, and polar bears, will sink or swim," Markey said.

But Democrats have yet to pass a mandatory plan to deal with climate change despite many proposals on Capitol Hill. Markey encouraged his congressional colleagues to enact legislation this fall to cut emissions that contribute to global warming.