The Cui-ui lakesucker, Chasmistes cujus, is listed as an endangered species, and Pyramid Lake, in Nevada, USA, is the only place in the world where it is found. The Pyramid Lake Paiute Tribe built a hatchery based in Sutcliffe in 1973 – it is now operated and maintained by the Pyramid Lake Fisheries.
The US Fish and Wildlife Service and the Tribe are conducting ongoing recovery efforts, focusing on the lower Truckee River. The hatchery is a precautionary measure against the extinction of the Cui-ui. In drought years, when there is not enough flow in the Truckee River to support ‘natural’ spawning, the hatchery is able to produce a viable year-class, which is vital to a healthy population structure.
Cui-ui once flourished in Pyramid Lake but the population began to decline after the construction of Derby Dam and the establishment of the Newlands Reclamation Project in 1905. Subsequent agricultural diversions further reduced the amount of water entering Pyramid Lake. As the Lake’s surface elevation receded, downcutting along the river resulted in the formation of a sand-bar delta at the mouth of the river which blocked access to the Cui-ui spawning grounds. Cui-ui are fresh-water spawners, and their eggs cannot survive in Pyramid Lake water.