Unit 45, Idaho

Elevation ranges from approximately 2,500 feet along the Snake River Plain up to 7,800 feet in the upper Mount Bennett Hills. The landscape transitions from flat sagebrush-covered basalt plains and lava rock benches along the Snake River to rolling foothills and rugged volcanic ridgelines in the Bennett Hills interior. Characteristic features include steep canyons, rhyolite and basalt outcrops, rhyolite columns rising over 100 feet (notably in the Gooding City of Rocks WSA), and the dramatic volcanic erosion landscape of the Little City of Rocks. Sharp lava rock on primitive roads poses a flat-tire hazard. Camas Prairie occupies gentler topography in the northern portion of the unit.

Primary highway access is via U.S. Highway 20 along the northern boundary, State Highway 46 on the eastern edge, U.S. Highway 26 along the southern edge, and Interstate 84 on the southern/western boundary to the Snake River at the King Hill Bridge. The Snake River defines the western boundary from King Hill to State Highway 51. The unit is administered primarily by the BLM Four Rivers Field Office (Elmore County portions) and the BLM Shoshone Field Office (208-732-7200, Gooding County portions). A network of BLM roads provides access to the interior, though many are primitive and subject to washouts; four-wheel-drive is strongly recommended in wet conditions. Six BLM Wilderness Study Areas within or adjacent to the unit—Little City of Rocks, Black Canyon (I), Gooding City of Rocks East, Gooding City of Rocks West, Deer Creek, and King Hill Creek—are closed to motorized vehicles. The Bennett Hills Backcountry Conservation Area (120,800 acres, designated August 2023) is managed by the BLM to conserve migration corridors and protect hunting access. The C.J. Strike Wildlife Management Area (11,008 acres in Elmore and Owyhee Counties) borders the unit along the Snake River; short-range weapons only apply within the WMA and portions close to motorized access February 1–July 31. The Motorized Hunting Rule applies unit-wide from August 30 through November 14. Three Island State Park within the unit boundaries is closed to hunting.

The unit is predominantly rangeland (approximately 78%), consisting of sagebrush-steppe and native bunchgrass across the lower benches and Snake River Plain. Higher elevations in the Bennett Hills support pine and fir timber, with junipers and mountain mahogany on mid-elevation ridges and draws. Riparian corridors along creeks and the Snake River host cottonwood, willow, mountain maple, and alder. Aspen groves, tobacco brush, Indian paintbrush, and lupine appear at higher elevations, particularly within the Deer Creek WSA. Irrigated agricultural lands occupy a small portion of the unit along valley bottoms.

Mule deer are the primary big game species; the unit is regionally noted for producing mature bucks due to limited hunting pressure and a predominantly controlled-hunt structure. Elk (Rocky Mountain elk) inhabit the Bennett Hills from summer through late fall and use lower sagebrush winter range; the Bennett Hills BCA provides critical winter habitat and migration corridors for multiple elk herds. Pronghorn antelope occupy the sagebrush plateau country, particularly in the Mount Bennett Hills and associated BLM rangelands; six distinct mule deer, elk, and pronghorn herds use the Bennett Hills as winter range and migration corridor. Black bear are present at lower densities in the timbered higher elevations. Mountain lion occupy the unit year-round following mule deer. Gray wolf has re-established presence in the region and is a huntable species. Chukar partridge, Hungarian partridge, California quail, ring-necked pheasant, sage-grouse, and sharp-tailed grouse represent significant upland game. The Snake River corridor is adjacent to the Snake River Birds of Prey National Conservation Area.