Conserving the Nature of America

News Release

Fish and Wildlife Service Reinstates Proposal to Protect Desert Reptile

December 7, 2005


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

The U.S. Fish and Wildlife Service published a notice in todays Federal Register announcing the reinstatement of a 1993 proposed rule to list the flat-tailed horned lizard (phrynosoma mcallii) as a threatened species under the Endangered Species Act. This action complies with the terms of a Court Order issued on 1November 17, 2005, by the U.S. District Court for the Southern District of California.

This most recent legal challenge centers on the issue of whether the Service adequately evaluated the lizard's lost habitat and whether that habitat was a significant portion of the range when it withdrew the proposed listing rule in 2003.

A new final listing decision must be submitted to the Federal Register for publication by April 30, 2006.

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 Endangered Species Act. The proposed listing was first withdrawn in 1997, based on a signed agreement to implement a Rangewide Management Strategy for conservation and management of sufficient habitat to maintain viable populations of the species throughout its geographical range.

The decision to withdraw the proposed listing was challenged in court by Defenders of Wildlife. The U.S. District Court for the Southern District of California upheld the Services decision to withdraw the proposed rule in 1999, but the case was appealed. In a July 31, 2001, ruling the Ninth Circuit Court of Appeals vacated the District Courts ruling, and ordered the Service to reinstate the 1993 proposed rule and make a new final listing determination for the species.

In January 2003, the Service again withdrew the proposed listing of the flat-tailed horned lizard, based on a determination that the threats to the species were not as significant as earlier believed and current available data did not indicate threats to the species and its habitat were likely to endanger the species in the foreseeable future throughout all or a significant portion of its range.

Found only in portions of California, Arizona, and Mexico, 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.

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