The sage-grouse (Centrocercus urophasianus) is the largest grouse species and the only one found only in sagebrush habitat. Although largely absent from higher elevation areas of Greater Yellowstone, the sage-grouse was common in Jackson Hole and other Western grasslands in the late 1800s. Since then, sagegrouse numbers have declined throughout the species’ range, even in Jackson Hole where most of the land is protected from development. Biologists are concerned about the prospects for this sage-grouse population because of its relative isolation and small size. Sagegrouse are most visible from March to mid-May, when they congregate at leks where males perform elaborate displays to attract females.