Three environmental groups on Monday petitioned the U.S. Fish and Wildlife Service to designate critical habitat for the imperiled Pacific pocket mouse.
Such a designation could become the biggest environmental obstacle to a proposed 16-mile toll road in south Orange County.
"There are only three known populations of the Pacific pocket mouse," said David Hogan of the Center for Biological Diversity's San Diego office. "There could be no justification for the loss of any of those populations."
There are thought to be as few as eight surviving mice in a single population at the Dana Point Headlands. In the two other populations, there are about 50 mice on both sides of San Mateo Creek, which is in the path of the proposed toll road, and 1,000 mice in Camp Pendleton, Hogan said.
There may already be good news for the pocket mice at the Dana Point Headlands. The site's owners are in "advanced negotiations" with state and federal wildlife officials to set aside a 24-acre preserve there.
The smallest of all pocket mice--four to six inches long, including tail--lives in sandy coastal bluffs up to two miles inland from the Pacific Ocean. Its range once stretched from Marina del Rey almost to the Mexican border.
The Center for Biological Diversity, the Natural Resources Defense Council and the Endangered Habitats League jointly filed the petition for critical habitat--land considered crucial for the survival of an endangered species. They are asking that 20 spots in Orange and San Diego counties be included. A preliminary decision is expected within 90 days.
Critical habitat includes not only land already occupied by a species but also suitable land to expand into. Such a designation means that landowners who receive federal funding or need a federal permit must receive approval from the Fish and Wildlife Service before they destroy or alter habitat.
The Pacific pocket mouse was listed as endangered in 1994. The service did not designate critical habitat then because staffers said they had heard from an unknown person who said he would destroy the only known population at that time--on the Dana Point Headlands. Critical-habitat maps would have allowed him and others to find that population, they said. But since then, the location of the mice has been repeatedly pinpointed in studies and maps.
"That rationale no longer holds water," said Andrew Wetzler, an attorney with NRDC's Los Angeles office.
