Press Release
Service Seeks Public Comment on Quitobaquito Tryonia Proposed Listing and Critical Habitat

The U.S. Fish and Wildlife Service seeks public comment on a proposal to list the Quitobaquito tryonia, a species of springsnail, as endangered under the Endangered Species Act (ESA). The Service is also requesting input on a proposal to designate 6,095 square feet of land as critical habitat for the species within Organ Pipe Cactus National Monument, Pima County, Arizona.

Quitobaquito tryonia is a small freshwater snail with a conical shell that measures 0.05 to 0.08 inches (1.4 to 2.1 millimeters) in length and is typically clear, gray or black in color. Its diet primarily consists of a substance called periphyton, which is a mixture of algae, bacteria, fungi, protists and dead organic material.

After a review of the best available scientific and commercial information, the Service determined the Quitobaquito tryonia is at risk of extinction because of spring modification, and the effects of drought and climate change climate change
Climate change includes both global warming driven by human-induced emissions of greenhouse gases and the resulting large-scale shifts in weather patterns. Though there have been previous periods of climatic change, since the mid-20th century humans have had an unprecedented impact on Earth's climate system and caused change on a global scale.

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. The number of known populations has already been reduced by 50 percent because of these factors.

Historically, Quitobaquito tryonia was found at a total of three spring complexes near the US-Mexico border in the southwest corner of Organ Pipe Cactus National Monument. It has been extirpated from both the Williams and Burro Springs systems. Today it is only known to reliably occur at its namesake site, in the Quitobaquito Spring channel and a nearby seep.

The word Quitobaquito is of Spanish and O’odham origin, and the area around the springs has been inhabited by people for at least 12,000 years. The Hia-Ced O’odham people used the springs as a stopover before continuing their Sea of Cortez to the Gila River journeys; their ancestral Hohokam used the springs as a part of their salt, obsidian, and shell trade routes, and for irrigation for centuries prior to the arrival of Europeans in the 1600s. Large-scale management of the springs likely began in 1863 when ranchers excavated a pond and irrigation ditches and built a dam, largely severing connections to the Rio Sonoyta in Mexico and curtailing spring habitat availability.

In 1989, as part of a restoration and conservation effort, a concrete spring channel was installed, creating a more stable system. National Park Service staff regularly remove dense vegetation from the spring channel in order to maintain stream flow and provide a mosaic of habitat types throughout the spring channel.

Native aquatic ecosystems contain some of the highest levels of biodiversity in the Southwest. Their protection and conservation is an American value and is critical to many species of aquatic insects, fish, amphibians, reptiles, waterfowl and other wildlife, as well as humans. It is the Service’s responsibility to protect Quitobaquito tryonia, work with partners to manage threats to the species, and encourage healthy aquatic communities.

The Service submitted this draft rule to the Federal Register today. Comments must be received within 60 days of its publication in the Federal Register. Information on how to submit comments will be available at by searching under docket number FWS–R2–ES–2023–0073. The public may also submit comments via email to Information on how to request a hearing is also included in the Federal Register notice. For more information, visit the Quitobaquito tryonia species profile page.

2023 marks the 50th anniversary of the Endangered Species Act of 1973, the most significant piece of endangered species legislation and one of the world’s most important conservation laws. The Act provides a critical safety net for fish, wildlife and plants and has prevented the extinction of hundreds of imperiled species, as well as promoted the recovery of many others, and conserved the habitats upon which they depend.

America’s fish, wildlife and plant resources belong to all of us, and ensuring the health of imperiled species is a shared responsibility. The Service is actively engaged with conservation partners and the public in the search for improved and innovative ways to conserve and recover imperiled species. To learn more about the Endangered Species program.

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Aquatic environment