Today's New York Times has this article on whether and how EPA's plans to regulate carbon dioxide emissions under the Clean Air Act will affect Interior's decision whether and how to regulate the same under the ESA. The article includes a revealing quote from a Fish and Wildlife spokesman:
"We have zero legislative authority to regulate carbon emissions. That's just not what we do," service spokesman Josh Winchell said in February. "With the polar bear, the science definitely pointed to climate change, but that doesn't all of a sudden give us the authority to address the underlying cause, which is carbon emissions."