The U.S. Fish and Wildlife Service (Service) is proposing to provide the Sonoyta mud turtle with the protections of the Endangered Species Act. The Service utilized a robust Species Status Assessment (SSA) of the Sonoyta mud turtle current and future condition to arrive at a proposed determination that the subspecies is in danger of extinction throughout its range on the U.S.-Mexico border. A 60-day public comment period will begin upon publication of the proposal in the Federal Register tomorrow.
The Sonoyta mud turtle is a less than six-inch aquatic turtle with an olive brown to dark brown upper shell (carapace) and a hinged the lower shell (plastron). Long barbels (whisker-like organs) are typically present on the chin, and its feet are webbed. The subspecies is closely related to the more populous and widely distributed Sonora mud turtle.
The Sonoyta mud turtle is an isolated subspecies, localized in the Rio Sonoyta basin in Arizona and Sonora, Mexico – an extremely arid environment. Sonoyta mud turtles are require aquatic habitat to survive, but use rare, permanently wetted riparian riparian
Definition of riparian habitat or riparian areas.
Learn more about riparian habitat for nesting, moving between intermittent sources of water, and estivating during drought. Today, there are five known remaining populations of Sonoyta mud turtle – one in the U.S. on the Organ Pipe Cactus National Monument in Arizona and four in Sonora, Mexico. These populations occupy less than 20 percent of the subspecies’ historical range.
“Our scientific assessment of the Sonoyta mud turtle and the threats it faces clearly indicate that it is in danger of extinction,” said Steve Spangle, the Service’s Arizona Field Supervisor. “Protecting it as an endangered species would marshal increased attention and the resources needed by our U.S. and Mexican conservation partners to improve and expand its dwindling habitat and populations.”
The most significant stressors for the Sonoyta mud turtle are the loss of aquatic and riparian habitat related to agricultural and municipal groundwater pumping, and long-term drought. Groundwater pumping and drought affect the amount of surface water and subsurface moisture available for the Sonoyta mud turtle. Reductions in riparian habitat further decrease subsurface moisture, due to loss of shade, needed for nesting sites and drought refuge for hatchlings, juvenile and adult turtles. Reduction in aquatic habitat also affects the invertebrate prey and space available for mud turtles. Much of the aquatic habitat in Mexico’s Sonoyta basin is currently supplied by human waste-water effluent, resulting in water quality and permanency concerns.
The only U.S. population is at Quitobaquito Springs on the Organ Pipe Cactus National Monument and is the most resilient of the populations. National Park Service staff continues to implement actions to stabilize the water levels in the pond at Quitobaquito Springs. The inter-agency Quitobaquito Rio Sonoyta Work Group is currently maximizing conservation actions for this population in the U.S, as well as other populations in Mexico. This group includes the National Park Service, Arizona Game and Fish Department, private citizens, and the Service. Members of the group participated in developing the species status assessment.
The Service will accept comments received or postmarked by or before November 21, 2016. For more information on the Species Status Assessment, images, other information about the Sonoyta mud turtle, the endangered listing proposal, what to comment on, or how to submit comments, see the Federal Register notice on our web site at http://www.fws.gov/southwest/es/arizona/.
A proposal to designate critical habitat for the Sonoyta mud turtle will be available in the near future. A final listing determination is anticipated within a year.
