Conserving the Nature of America

News Release

Fish and Wildlife Service Reinstates Proposal to Protect Rare Desert Reptile

December 26, 2001


Division of Public Affairs
External Affairs
Telephone: 703-358-2220

Public Comment Period Reopened for 120 days

The U.S. Fish and Wildlife Service today reinstated an amended 1993 proposal to list the flat-tailed horned lizard (phrynosoma mcallii) as a threatened species under the Endangered Species Act. The Service has also opened a 120-day public comment period on the proposed rule. This action complies with the terms of a Court Order issued on October 24, 2001, by the U.S. District Court for the Southern District of California.

The flat-tailed horned lizard is a small desert reptile that inhabits the arid valleys and flat lands of the western Sonoran desert. The species’ range includes the Coachella Valley in Riverside County, California; the Imperial and Borrego Valleys in San Diego and Imperial counties, California; southwestern Arizona; and northeastern Baja California and northwestern Sonora, Mexico.

On November 29, 1993, the Service published a proposed rule to list the flat-tailed horned lizard as threatened, under the Act. In 1997, Federal and State agencies -- including the Fish and Wildlife Service, Bureau of Land Management, Bureau of Reclamation, U.S. Marine Corps, U.S. Navy, Arizona Game and Fish Department, and California Department of Parks and Recreation -- signed a Flat-Tailed Horned Lizard Conservation Agreement and agreed to implement a Rangewide Management Strategy to conserve and manage sufficient habitat to maintain viable populations of the flat-tailed horned lizard throughout its geographical range.

On July 15, 1997, the Service withdrew its proposal to list the flat-tailed horned lizard as threatened based on three primary factors: 1) population trend data did not conclusively demonstrate significant population declines; 2) some of the threats to the species’ habitat were found to be less serious after publication of the proposed rule; and 3) the Service believed the approval of the 1997 Conservation Agreement and implementation of the Rangewide Management Strategy would further reduce the severity of threats to the lizard.

The decision to withdraw the proposed listing was challenged in court by Defenders of Wildlife. On June 16, 1999, the U.S. District Court for the Southern District of California upheld the Service’s decision to withdraw the proposed rule. The case was appealed and on July 31, 2001, the Ninth Circuit Court of Appeals vacated the District Court’s ruling. On October 24, 2001, the District Court ordered the Service to reinstate the 1993 proposed rule to list the lizard as threatened and to make a new final listing determination for the species. The Service must make a final listing determination for the lizard within 12 months of today’s notice.

"A significant amount of time has elapsed since the 1993 proposed rule was published," said Jim Bartel, Field Supervisor for the Carlsbad Fish and Wildlife Office. "The 120-day public comment period is necessary to ensure all interested parties have adequate time to provide us with the most current scientific and commercial information about the species’ status, distribution, and ongoing conservation efforts."

Found only in portions of California, Arizona, and Mexico, the flat-tailed horned lizard may be threatened by habitat loss and fragmentation associated with development, off-highway vehicle use, military activities, introduction of non-native plants, and pesticide use. In the United States, approximately, 1,244,000 acres of habitat remain for this species; 1,103,800 acres are in California and 140,300 acres occur in Arizona.

The flat-tailed horned lizard has a wide, flattened body, with a short tail. It measures about 3.2 inches in length, excluding the tail, and can be distinguished from other horned lizards by a dark stripe running down its back, the presence of two slender, elongated occipital spines, and the absence of external ear openings. Flat-tailed horned lizards have pale coloration that closely matches the soils on which they live. These desert reptiles feed almost exclusively on native harvester ants, consuming about 150-200 ants per day.

Notification of the reinstatement of the 1993 proposed rule to list the flat-tailed horned lizard as a threatened species and reopened public comment period will be published in the Federal Register on December 26, 2001. Written comments, data, and information about this proposal received by the Service by 5:00 p.m. on April 25, 2002, will be considered in any final listing determination. All comments and materials should be sent to Field Supervisor, Carlsbad Fish and Wildlife Office, 2730 Loker Avenue West, Carlsbad, California 92008. Requests for a public hearing must be received by February 11, 2002.

Comments may also be submitted by electronic mail to Please submit electronic comments in ASCII file format and avoid the use of special characters and encryption. Please include your name, and return address in the e-mail message. If you do not receive a confirmation from the system that your e-mail message was received, contact the Service directly by calling the Carlsbad Fish and Wildlife Office at 760/431-9440.