The federal government on Tuesday took the first step toward listing the polar bear as a threatened species.
The U.S. Fish and Wildlife Service said protection may be warranted under the Endangered Species Act, triggering a review process that could lead to its listing.
The service acted on a petition filed by the Center for Biological Diversity, which said polar bears could become extinct by the end of the century because their sea ice habitat is melting away due to global warming.
The Fish and Wildlife Service concluded that the petition "presents substantial scientific and commercial information indicating that listing the polar bear may be warranted."
The agency will begin a status review of the polar bear to determine if the species should be proposed for listing.