Amphibians
Dixie Valley Toad
Anaxyrus williamsi · also called Dixie Valley toads
In a small patch of geothermal wetland surrounded by miles of Nevada desert, the entire global population of the Dixie Valley toad goes about its life within an area smaller than most towns, a species whose complete existence depends on a single spring-fed basin continuing to flow.
Overview
The Dixie Valley toad, Anaxyrus williamsi, is a recently described amphibian confined entirely to a small geothermal spring-fed wetland within the Dixie Valley of Churchill County, Nevada. Its extraordinarily narrow range, among the smallest of any amphibian species, and its Endangered status tied to proposed nearby energy development make it one of the most precariously positioned amphibians in North America.
An entire species riding on one spring
Few animals anywhere depend as completely on a single, specific water source as the Dixie Valley toad does, its whole existence tied to one geothermal wetland small enough that a single development project nearby could put the entire species at risk.
Status
Endangered — confined to roughly a single square mile of geothermal wetland habitat, threatened by proposed nearby geothermal energy development.
Dixie Valley Toad: common questions
How small is the Dixie Valley toad's range?
The Dixie Valley toad survives entirely within a small geothermal spring-fed wetland covering roughly a single square mile in the Nevada desert, one of the smallest known ranges of any amphibian species anywhere, making its entire global population dependent on the continued health of this one location.
Why is the Dixie Valley toad endangered?
The Dixie Valley toad has been listed as Endangered because its naturally tiny range, combined with proposed geothermal energy development projects near its only known habitat, creates a serious risk that changes to the spring-fed wetland water supply could threaten the survival of the entire species at once.
When was the Dixie Valley toad recognised as its own species?
The Dixie Valley toad was formally described as a distinct species only in 2021, after genetic analysis confirmed that it was different from other closely related toads found in the surrounding region, making it one of the most recently recognised amphibian species in North America.
Where does the Dixie Valley toad live?
The Dixie Valley toad is found only within a geothermal spring-fed wetland in the Dixie Valley of Churchill County, Nevada, remaining closely tied to this permanent water source in an otherwise arid desert basin.