Polar bears on thin ice
Polar bear female and cubs. Credit: Steven Amstrup / USGS
The polar bear has become the icon of global warming, appearing in major motion pictures such as Arctic Tale, An Inconvenient Truth and Disney's earth, and in ad campaigns for organizations trying to raise awareness of how global warming affects wildlife. As the earth’s average temperature rises, the Arctic sea ice has started melting earlier in the year. Polar bears hibernate all winter, and then must journey to the edge of the polar ice every spring to hunt seals and other marine mammals. Since bears lose much of their body weight during winter, they have to find food quickly, and moms have to teach their cubs how to hunt. But with the ice melting earlier and earlier, the bears sometimes fall through the thin ice; their habitat is disappearing. While polar bears can swim, they can’t hunt in the ocean, and swimming tires them out and uses precious energy that they need to catch their prey.
The Center for Biological Diversity petitioned the U.S. Fish & Wildlife Service to list the polar bear in 2005, and after federal review and public comment, the polar bear was listed as a threatened species under the Endangered Species Act (ESA) in 2008 under the Bush Administration. The bears became the first species listed under the ESA solely because its habitat was threatened from global warming. However, the listing had one caveat, a “special rule” that declared actions outside the Arctic cannot be considered a threat to the bear and its habitat. In other words, groups cannot sue companies or governments contributing to global warming, for example over greenhouse gas emissions from power plants thousands of miles away. But in the end, global warming is the main threat to the bears.
“There seems to be a complete disconnect between the listing, which acknowledges climate change as the threat, and the special rule,” says Pamela Martin, Assistant Professor in Geophysical Sciences who studies global climate change at the University of Chicago. In 2006, Martin and 30 colleagues urged the U.S. Fish & Wildlife Service to list the polar bear under the ESA in a letter that summarized the best available science on global climate change. It said, in part, “In the Arctic, evidence from satellite data, submarine data, and oceanographic field observations reveal the diminished areal extent, shorter seasonal duration, and extensive thinning of sea ice. Summer sea ice cover in the Arctic has already been reduced in areal extent by 10-20 percent over the last 30 years.”
Martin laments Salazar upholding the special rule, “It’s as if the Secretary of the Interior is saying, ‘Here is why the polar bear is in trouble... but, we are going to ignore the source of the trouble.’"
If Salazar had discarded the rule, it could open the door for environmental groups to sue polluters for threatening the bears’ long-term survival, and provide a strong tool in the fight against global warming. Environmental groups, including the Center for Biological Diversity, National Wildlife Federation and The Sierra Club, voiced their disappointment at the decision.
President Obama has run on a platform of providing a new energy economy for America, tackling global warming, and making decisions with the best available science. That brings the question, is the Endangered Species Act the best way to tackle global warming? In a conference call with reporters, Salazar said he didn’t think so, “the Endangered Species Act is not the appropriate tool for us to deal with what is a global issue, and that is the issue of global warming.”
In an online Q&A about the special rule, the Department of the Interior stated, “the Department does not believe that a project-by-project ESA review of proposed actions that have the potential to increase greenhouse gas emissions, regardless of where they occur or how much they contribute to global greenhouse gas emissions, is the appropriate tool for addressing climate change impacts. A comprehensive approach is needed in order to protect the polar bear and other species that are impacted by climate change. The Administration is actively working with Congress to pursue such a comprehensive strategy.”
Martin agrees with the difficulty, but says that's besides the point. “Whether or not this is the absolute best way in the long-run to regulate greenhouse gases and other agents of global warming should not be the question at hand; the question at hand should be how best to uphold the endangered species act and protect listed species, in this case the polar bear,” she says. “While the special rule applies only to the polar bear, I am concerned that this signals a direction for future decisions on threatened species."
Biologists estimate the current population of polar bears at between 20,000 and 25,000. The bears are also protected under the Marine Mammal Protection Act.