The U.S. Fish and Wildlife Service (FWS) has proposed designating approximately 760,000 acres in California as critical habitat for four distinct population segments (DPSs) of the foothill yellow-legged frog, a species that is listed as either endangered or threatened under the Endangered Species Act (ESA). The critical habitat designation includes areas within the geographical range of the foothill yellow-legged frog that contain the physical or biological features that FWS has deemed essential to the species’ conservation, as well as areas outside the current range that are deemed necessary for the species’ recovery. EPA based its determination on the “best available scientific data after taking into consideration the economic impact, national security impact, and any other relevant impact of specifying any particular area as critical habitat.”