The United States Fish and Wildlife Service has said the Flat Tailed Horned Lizard will not be added to the Endangered Species List because its desert habitat in Southern California and Arizona is large enough for a self sustaining population. This is the forth time since 1993 that they have rejected pleas to add the lizard to the list stating that worries such as off road vehicles, military activity as well as urban development are not are bad on the species as previously thought. Each of the earlier withdraws from the listing was successfully challenged in court by Center for Biological Diversity, Defenders of Wildlife, the Sierra Club and the Horned Lizard Conservation Society. CBD legal director John Buse said they are trying to determine whether or not to push the issue further.