Clear Lake Refuge in northeastern California consists of approximately 20,000 acres of open water surrounded by over 26,000 acres of upland bunchgrass, low sagebrush, and juniper habitat. Small, rocky islands in the lake provide nesting sites for American white pelicans, double-crested cormorants, and other colonial nesting birds. The upland areas provide habitat for pronghorn antelope, mule deer, and sage grouse. The Clear Lake Reservoir is the primary source of water for the agricultural program of the eastern half of the Klamath Basin, with water levels regulated by the Bureau of Reclamation. Except for limited waterfowl and pronghorn antelope hunting during the regular California State seasons, the refuge is closed to all public access to protect fragile habitats and to reduce disturbance to wildlife. Some viewing of strutting sage grouse occurs in the spring from U.S. Forest Service Road 136, which runs along and through the refuge's southern boundary.