A federal judge Tuesday ordered the Bush administration to stop dragging its feet on the fate of polar bears and decide by May 15 whether declining sea ice in the Arctic threatens their existence. The ruling marks a victory for a coalition of environmentalists—the Center for Biological Diversity, Greenpeace and the Natural Resources Defense Council (NRDC)—which sued to force the U.S. Department of the Interior to decide whether to protect the hoary Arctic predators under the Endangered Species Act (ESA), which it had committed to do by January 9.

U.S. District Judge Claudia Wilken in Oakland, Calif., ruled that any further delay would be a violation of the intent of the ESA.

"The federal court has thrown this incredible animal a lifeline," Andrew Wetzler, director of NRDC's endangered species project, said in a statement. "The science is absolutely unambiguous that the polar bear deserves protection."

Wilken rejected the Interior Department's request to postpone its decision on polar bears until June 30, saying to do so violates "congressional intent that time is of the essence in listing threatened species" and ruled further that the agency had failed to prove that waiting "will not pose a threat to the polar bear."

According to the World Wildlife Fund, some polar bears are already starving as a result of changing conditions in the Arctic. And the U.S. Geological Survey recently reported that polar bear populations could drop precipitously in coming decades as the sea ice they rely on to hunt recedes as the globe warms. This past September, the National Snow and Ice Data Center, which collects polar and ice information for the government, announced that there was less sea ice covering the Arctic Ocean than at any time since satellite measurements began in 1979.

Critics of designating the animals as endangered charge that such a move is merely a smoke screen for efforts to stem global warming, such as curbs on greenhouse gas emissions. "What has become clear through this heavily litigated process is that listing the polar bear as a threatened species is not about protecting the polar bear but rather advancing a particular political agenda," Sen. James Inhofe (R–Okla.) said in a statement. Inhofe has previously called global warming "the greatest hoax ever perpetrated on the American people."

Interior Department spokesman Shane Wolfe said that the agency is reviewing the ruling and "will evaluate the legal options and will decide the appropriate course of action." But environmentalists hailed the decision.

"By May 15th, the polar bear should receive the protections it deserves under the Endangered Species Act," said attorney Kassie Siegel, Climate, Air and Energy Program director at the Center for Biological Diversity. That "is the first step toward saving the polar bear and the entire Arctic ecosystem from global warming."