From a Center of Biological Diversity press release:

WASHINGTON, D.C.– Utilizing authority granted to him by Congress, Interior Secretary Ken Salazar rescinded a rule passed in the final days of the Bush administration that weakens the Endangered Species Act by exempting thousands of federal activities, including those that generate greenhouse gases, from review under the Endangered Species Act. Salazar, however, did not take action to rescind a rule that sharply limits protections for the threatened polar bear despite having authority to rescind this rule as well.