Watching a Species Disappear

About 22,000 polar bears live on and near the Arctic Sea ice in northern Canada, Greenland, Norway, and Russia. This flagship species reigns atop the frozen habitat’s food web, composed of seals, fish and sea birds, krill and small crustaceans, and finally zooplankton. Polar bears are the world’s largest terrestrial carnivore (775–1,400 lb. [350–635 kg]), but today their average weight is decreasing due to a lack of food and a melting habitat.

Climate change has raised temperatures in the Arctic about five times faster than warming in the rest of the world. As a consequence, the Arctic Sea ice that builds and thickens each winter has decreased year by year, leaving less platform on which polar bears hunt ringed, harp, and bearded seals. Less ice means longer swims across open water for the bears that are already receiving fewer calories. In 2005 the marine biologist Charles Monnett alerted the world to the problem at the top of the world. He told Britain’s Sunday Times, “We know short swims of up to fifteen miles are no problem, and we know that one or two may have swum up to 100 miles. But that is the extent of their ability, and if they are trying to make such a long swim and they encounter rough seas they could get into trouble.” Meanwhile, hungry bears on land have started to wander inland to find food; some have broken into houses in northern Canadian villages. In 2006 Interior Secretary Dirk Kempthorne proposed listing the polar bear as threatened on the endangered species list, reasoning, “We are concerned the polar bears’ habitat may literally be melting.” Computer-generated models used in polar research today predict the sea ice will have completely melted by 2080 due to global temperature increases.

Polar bears have long confronted other challenges from hunting to the accumulation of toxic chemicals in their bodies, yet 25,000 bears still roam the Arctic and may represent a healthy population. In May 2008 Kempthorne nevertheless announced that the polar bear would receive protections under the Endangered Species Act. This represents the first listing of an animal whose numbers have not yet begun to decrease and also the first listing related directly to global warming.

Opponents of the polar bear’s new protected status come mainly from oil interests; drilling companies eye the Arctic as a potential new oil source. M. Reed Hopper of the Pacific Legal Foundation voiced just such opposition of the listing: “Never before has a thriving species been listed nor should it be.” Kempthorne admitted to the difficulties of listing the bear as protected, and at the same time explained the polar bear’s uncertain future: “When the Endangered Species
Act was adopted in 1973, I don’t think terms like climate change were part of our vernacular.” No one knows at this time whether the polar bear’s habitat will soon include tankers, drilling rigs, and possible oil spills or remain an undisturbed spot at the top of the globe.