LOS ANGELES — Two U.S. explorers plan to start a four-month summer expedition to the North Pole next month to gather information on the habitat of an animal they believe could be the first victim of global warming -- the polar bear.

Lonnie Dupre and Eric Larsen plan to travel 1,100 miles by foot and canoe over the Arctic Ocean to test the depth and density of the ice in summer in a mission sponsored by Greenpeace, the environmental group said Thursday.

According to some scientific predictions, the Arctic Ocean could become ice-free in the summer within a hundred years.

Polar bears cannot survive without sea ice and the U.S. government said in February it would consider whether the bears should be protected under the Endangered Species Act.

Unusually heavy snow and ice last year forced Dupre and Larsen to call off a similar mission, but they now plan to launch Project Thin Ice 2006 -- Saving the Polar Bear on May 1 from Canada, traveling to the North Pole and then back to Greenland.

"Last year I came face to face with a polar bear and while I was scared, I also felt a deep respect for the fact that I was in this bear's territory and that it was global warming that was forcing this magnificent creature toward the brink of extinction," Dupre said in a statement.

Polar bears are losing weight as their hunting grounds melt away, making it harder for them to hunt seals, experts say. The polar bear population fell 14 percent to just 950 in the 10 years to 2004, according to Greenpeace and the Natural Resources Defense Council.

Source: Reuters