Officially known as Rallus longrostris yumanensis , the Yuma clapper rail was listed as endangered in 1966 by the U.S. Fish and Wildlife Service, mostly due to the loss of its marsh habitat. The total population is estimated at slightly more than 600 birds. On the other hand, they do not compete well with other fish, often becoming a food source for their competitors. Several ponds in the Coachella Valley Preserve have been successfully cleared of non-native predatory fish, in order to provide refuges for the desert pupfish. Adult males are rarely larger than 3 inches in lengty and during the breeding season, they turn bright blue with lemon-yellow tails and fins.
Females are smaller, and generally have tan to olive backs and silvery sides.
During the winter when water temperatures cool, desert pupfish may bury themselves in loose debris on the bottom of the ponds, and become dormant. The U.S. Department of the Interior Fish and Wildlife Service displays a photo and description of the desert pupfish and other pupfish . It eats insects and some plant material in the blown-sand ecosystem. The Coachella Valley fringe-toed lizard was listed by the U.S. Fish and Wildlife Service as a threatened species in 1980. It apparently has been isolated from other salamander species for hundreds of thousands to several million years, and is a relic from wetter geologic epochs.