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Mono Basin sage grouse (Centrocercus urophasianus) | ESA status: none

Mono Basin sage grouse

The Mono Basin (or “bi-state”) sage grouse is a genetically distinct population of greater sage grouse that occurs on the border of California and Nevada.

Mono Basin sage grouse facts

Mono Basin sage grouse are loners among sage grouse in the West. Sage grouse are a widely distributed but sparsely populated species that occur in 11 western states and two Canadian provinces. Some populations are isolated from others due to distance, geographical features, and other factors. The Mono Basin sage grouse is the most unique of these isolated groups.

Recent research found that Mono Basin sage grouse have “a unique history of isolation distinct from all other populations.” Geneticists even noted that the Mono Basin population may warrant consideration as a new subspecies of sage grouse.

Aside from their unique genetic traits, Mono Basin sage grouse appear and behave as other sage grouse, including engaging in a fascinating mating ritual each spring.

Mono Basin sage grouse habitat

Mono Basin sage grouse distribution is limited to an area approximately 18,310 square kilometers (7,069 square miles) in size, including and extending north, east and south of the Mono Basin in southeast California and southwestern Nevada. The Mono Basin population itself is fragmented into more than 15 subpopulations, many of which are isolated from each other.

What WildEarth Guardians is doing to protect Mono Basin sage grouse

Like other sage grouse, the Mono Basin population has experienced significant declines from historic numbers, and only about 3,000 birds remain.

The U.S. Fish and Wildlife Service determined that the genetically distinct and geographically isolated Mono Basin sage grouse qualified for separate consideration for protection under the Endangered Species Act. The agency declared the Mono Basin population, now known as the “Bi-State Distinct Population Segment of greater sage grouse,” a candidate for listing in 2010. Unfortunately, the population was denied listing in 2015.

In addition to pressing for listing under the Act, WildEarth Guardians is working to prevent harmful livestock grazing in Mono Basin sage grouse range, rein in destructive off-road vehicle use in key habitats, and prevent industrial development in breeding and nesting areas in order to protect the unique evolutionary heritage of this isolated population.