On global warming, the canary signaling trouble in the mine shaft is the polar bear trying to survive in seas with fewer ice floes. Last week, the plight of the polar bear got the official recognition of the U.S. Department of the Interior. Somewhat.

Interior Secretary Dirk Kempthorne said polar bears are a threatened species and will be listed for protection under the Endangered Species Act -- which is good. But this was a belated and unenthusiastic move: The department had been sued by environmental groups, and a federal judge had ordered the listing by last Thursday.

Moreover, Mr. Kempthorne was at pains to add caveats in case anyone used the designation to try to block oil and gas drilling in the area where the polar bears are threatened -- which indeed was the motivation for the lawsuit. Mr. Kempthorne made clear that drilling activity in the area would be governed by the Marine Mammal Protection Act, with its supposedly stricter standards, and not the Endangered Species Act.

So, true to the style of the Bush administration, the Interior Department moved to protect the polar-bear victims of global warming while steadfastly drawing a line between their problem and the bigger problem of climate change that made them threatened in the first place.

The irony is that Interior had little choice but to concede that polar bears are at risk of becoming endangered in the foreseeable future -- the standard under the act -- because of the loss of sea ice in their habitat.

The science is undeniable and Mr. Kempthorne did not shrink from these facts: Last year, Arctic sea ice fell to the lowest level ever recorded by satellite, 39 percent below the long-term average from 1979 to 2000. The amount of sea ice lost between 2002 and 2007 exceeded all previous record lows.

If this keeps up, polar bears will be in deeper trouble. They are not in imminent danger -- some 20,000 to 25,000 roam the Arctic, which is up dramatically from the 1960s, when they were in danger of being hunted to extinction. But if the ice continues to melt, they will have fewer platforms on which to hunt and rest.

The new designation will help, but until protection of habitat goes along with protection of polar bears, until oil drilling gives way to alternate forms of energy, then all people can do is wish the polar bears luck.