Federal Government Continues to Weigh ESA Listing of Polar Bears

Published April 1, 2008

The U.S. Fish and Wildlife Service (FWS) has postponed a decision on whether to list polar bears as “threatened” under the Endangered Species Act.

The FWS stated the extension, announced on January 8, was necessary in order to take into account public comments and expert opinions regarding the bears.

The process began in December 2006 when Secretary of the Interior Dirk Kempthorne announced the Bush administration’s plan to consider listing the polar bear as a threatened animal on the U.S. Endangered Species list. The decision to consider listing the polar bear settled a lawsuit filed by Greenpeace and the Natural Resources Defense Council.

Polar Bear Numbers Stable

Kempthorne has acknowledged polar bear populations are not currently in decline, but he has stated concern over predictions global warming may cause a retreat in Arctic sea ice. Global warming alarmists have claimed a retreat of sea ice would make it more difficult for polar bears to hunt seals.

If the bear is finally listed as threatened, it will be the first time a species was placed on the Endangered Species list based on global warming projections.

In support of their argument, environmentalists have presented only one academic study showing any present harm to polar bears. That study examined a single population of polar bears in Canada’s Western Hudson Bay and linked an early break-up of ice in the bay to a 21 percent decline in the polar bear population.

Other research, however, indicates polar bear populations are actually growing overall, including in areas where ice is receding.

Flawed Methodology

FWS cited nine administrative reports in support of its decision to consider listing polar bears. The reports shared a number of common assumptions regarding computer model predictions of retreating Arctic sea ice. Some models predict a steep decline in Arctic sea ice, leading to predictions that seal populations will decline as the sea ice retreats.

On January 30, 2008, however, J. Scott Armstrong, a researcher in the field of scientific forecasting methods, exposed flaws in the sea ice models at a hearing held by the Senate Environment and Public Works Committee.

Armstrong and his colleagues had assessed the methodology used by climate forecasters to predict future sea ice conditions and polar bear population levels. Armstrong’s team audited the methods used in reports cited by FWS, and Armstrong determined each of the studies violated a majority of the forecasting principles that applied to their research.

On average, Armstrong found, the authors properly applied only 12 percent of their relevant principles. “In what occupations would work that follows 12 percent of proper procedures be considered acceptable?” Armstrong asked at the hearings.

Real-World Observations

Armstrong also noted a good deal of real-world evidence casts doubt on predictions of rapid Arctic ice loss. According to Armstrong, coastal stations in Greenland are cooling, and average summer air temperatures at the summit of the Greenland Ice Sheet have fallen by 4ºF per decade since measurements began in 1987.

Moreover, Armstrong noted, a study commissioned by Canada’s Department of Fisheries and Oceans examining the relationship between air temperature and sea ice coverage concluded “the possible impact of global warming appears to play a minor role in changes to Arctic sea ice.”

Though polar bears currently eat seals more than any other food source, research shows they have a varied diet when other foods are available. The bears are known to eat fish, kelp, caribou, ducks, sea birds, beluga whales, musk oxen, and scavenged whale and walrus carcasses when they are available.

Dr. Mitchell Taylor, a biologist recently retired from the Nunavut Territorial government in Canada, pointed out in testimony to the U.S. Fish and Wildlife Service that modest warming may be beneficial to the bears because it creates better habitat for seals and makes blueberry bushes more abundant.

Bears Not Threatened

“Ice has declined in some areas of polar bear range, and this decline in ice appears to have reduced the viability of two populations–at Western Hudson Bay and the Southern Beaufiort. However, polar bears are currently abundant in all populations, and are not threatened with extinction by sea ice reductions,” Taylor said in an interview for this story.

“According to a recent paper from the U.S. Geological Survey, the total reduction in optimal polar bear ice habitat will be only 30 percent in 100 years. Polar bears have always sustained viable populations in areas where they seek onshore retreats during the open water season,” Taylor continued.

Taylor added, “The reductions in range and numbers that would occur if the computer sea ice projections are correct would not reduce the sea ice enough to cause the extinction of polar bears as a species. There is certainly no imminent danger of even a reduction in polar bear range. It would be prudent to increase monitoring and harvest management activities, but I think it is premature to declare polar bears to be threatened with extinction until more is known about climate change, the simulation models that predict it, and the ability of polar bears to adapt to changing conditions.”

H. Sterling Burnett, Ph.D. ([email protected]) is a senior fellow with the National Center for Policy Analysis, a nonpartisan, nonprofit research institute based in Dallas, Texas.