Bird Biology

Female sage-grouse walking in the sagebrush

The greater sage-grouse (hereafter sage-grouse) are a large ground dwelling bird.  They can be up to 30 inches long and two feet tall, weighing from two to seven pounds. Females are mottled brown, black, and white which serves as camouflage from predators. Males are larger and more colorful than females with white feathers around the neck and bright yellow air sacs on their breast, which they inflate during their mating display. The birds occur at elevations ranging from 4,000 to over 9,000 feet and are dependent on sagebrush for cover and food.  

Male sage-grouse strut while on a lek

During the breeding season, male sage-grouse gather together and perform courtship displays in areas called leks, which are relatively open sites surrounded by denser sagebrush. Males defend individual territories within leks by strutting with tails fanned and emitting drumming sounds from the air sacs on their chests to attract females. The mating season generally begins in March but may vary depending on weather conditions. Females lay a clutch of six to nine eggs from mid-March to mid-May. Sage-grouse hens raise one brood in a season.  Throughout much of the year, adult sage-grouse rely on sagebrush to provide roosting, cover, and food.  In winter, over 99 percent of sage-grouse diet is sagebrush leaves and buds.