Lahontan cutthroat trout is a native fresh-water trout species found only in the Humboldt River and other streams in northern Nevada and southern Oregon. 

A relic of the ancient Lake Lahontan that once covered much of this region, Lahontan cutthroat trout have been listed as a "threatened" species under the Endangered Species Act since the early 1970's.  Only a few small and isolated populations persist, and continue to decline as a result of dams, diversions, grazing, and other impacts.  Global warming is adding further threats, by causing hotter and drier conditions that are further depleting streams in this region.

Preserving Lahontan cutthroat trout will require federal and state agencies to stop allowing degradation of Lahontan cutthroat trout streams, including by public lands livestock grazing; and private irrigators and ranchers to remove or modify diversion dams that block fish movement and take excessive quantities of water out of the streams.