Kanab ambersnail (Oxyloma haydeni ssp. kanabensis), which is monitored at Vaseys Paradise in Grand Canyon National Park,
Arizona (photograph by Roy Averill-Murray, Arizona Game and Fish Department).
Vaseys Paradise (photograph by Jeff Sorensen, Arizona Game and Fish Department).
The Kanab ambersnail (Oxyloma haydeni ssp. kanabensis) is a small terrestrial snail that was added to the Federal list of endangered species in 1992. Dependent upon wetland vegetation for food and shelter, the Kanab ambersnail is currently found at three locations: Vaseys Paradise and Elves Chasm—springs in Grand Canyon National Park—and a private wetland near Kanab, Utah. The USGS Grand Canyon Monitoring and Research Center (GCMRC), in cooperation with the Arizona Game and Fish Department and the National Park Service, monitors the abundance of the Kanab ambersnail and its habitat at Vaseys Paradise, and oversees research activities for the Grand Canyon population under the auspices of the Glen Canyon Dam Adaptive Management Program.
The number of snails at Vaseys Paradise has not changed significantly since 1998. While habitat for the snail has increased, snail numbers have not experienced a similar increase. The lack of increase in snail numbers may be associated with soil moisture, shifts in the composition of the plant community as the result of drought, and mortality associated with trampling by bighorn sheep (Ovis canadensis). Because Vaseys Paradise provides a reliable source of vegetation in a drought, bighorn sheep have been attracted to the site in recent years, trampling vegetation occupied by the snails.
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