WASHINGTON -- Behind the legal wrangling Wednesday in a federal courtroom in Washington was a central question about the Endangered Species Act: What, if anything, can be done to save polar bears as the Earth warms and sea ice recedes?
Courts have done plenty in the past to protect endangered or threatened species, including putting a halt to logging or construction, noted U.S. District Judge Emmet Sullivan. But, he asked, what should be done when the primary threat to polar bears is the loss of their sea- ice habitat?
"How do we fix that?" the judge asked Kassie Siegal of the Center for Biological Diversity, the lead lawyer for the environmental coalition seeking to change polar bears from merely threatened to endangered status.
"Deep and rapid greenhouse gas reductions," Siegal said.
Her answer got at the heart of what environmental groups hope to do with their lawsuit: force the Obama administration to reconsider a rule that prohibits the Endangered Species Act from being used as a tool to regulate greenhouse gases.
But both Congress and the Obama administration have failed so far to successfully enact legislation or rules regulating greenhouse gas emissions. Sullivan's question suggested he, too, was skeptical about what more could be done by the courts. Already he has asked the U.S. Fish and Wildlife Service to further explain how it made its determination in 2008 that polar bears are merely threatened, and not endangered.
Wednesday, environmentalists argued that the bears should be considered endangered, and that the Fish and Wildlife Service misread its own science in determining they were only threatened. Based on the projected loss of sea ice in the coming decades, polar bears are already so threatened they should be considered endangered, they argued.
The state of Alaska, which opposes even the threatened listing, also disputed how federal scientists interpreted their own research, albeit from a slightly different point of view. The state disputes that the Fish and Wildlife Service could derive population estimates from sea ice projections, said Murray Feldman, the state's Boise, Idaho-based attorney in the case.
The state also holds the position that since polar bears currently have a robust population that covers much of its historic territory, they shouldn't be listed as threatened or endangered like species that face more easily addressable threats to their survival.
"What, under the law, is the appropriate management framework for this species?" Feldman said.
It's undisputed that polar bear habitat is shrinking, but it's less clear how fast, and what it will mean to the future polar bear population, currently estimated at 20,000 to 25,000.
Environmentalists argued Wednesday in court that the ice is melting even faster than the models are predicting, an assertion supported by many researchers. Arctic sea ice is declining at an increasing rate all months of the year, according to the National Snow and Ice Data Center in Colorado. That decline is stronger in summer months, and researchers who study climate and sea ice anticipate that at some point in the near future, the Arctic Ocean will lose its ice cover completely in late summer.
Polar bears spend most of their lives on sea ice and use it to travel, breed and hunt, especially for their main prey, ringed seals, which are the only seals that can live in completely ice-covered waters. If the Arctic continues its current melting trend, polar bear populations worldwide could decline by as much as two-thirds by mid-century. They could be near extinction by the end of the century.
Their loss would be significant to the Arctic ecosystem, said Brendan Cummings of the Center for Biological Diversity, as well as symbolic. Putting legal issues aside, listing polar bears as endangered would force the government to grapple with the consequences of climate change, he said.
"It's a recognition that global warming is not just a distant threat, but in fact a real threat," he said.
Government lawyers, though, said that even with its status listed as threatened, much is being done to protect the bears, including developing critical habitat boundaries. Their status as a threatened species also prompted additional study of the bears, said Clifford Stevens, a Justice Department attorney representing the Interior Department's position in the case
"This is not a 'no-list' situation: The government has listed the species," he said. "It has done exactly what Congress asks be done: Species that face likely endangerment in the future be listed as threatened."