The Greater Hart-Sheldon, a region anchored by Hart Mountain National Antelope Refuge and Sheldon National Wildlife Refuge, provides essential habitat for hundreds of animals who depend on sagebrush plants, including pronghorn, greater sage-grouse and the pygmy rabbit. California Bighorn sheep occupy the refuge, primarily around steep, rocky cliffs of the Hart Mountain refuge. As early as June, hundreds of thousands of birds will flock to the northwest corner of the Greater Hart-Sheldon
The Hart Mountain National Antelope Refuge is distant from population, relatively little visited with far more pronghorn antelope, bighorn sheep, sage grouse, mule deer and other wildlife than people..