Unit 45C, Arizona

The unit is dominated by the Castle Dome Mountains, with elevations ranging from roughly 700 feet on the desert flats to 3,780 feet at Castle Dome Peak. Terrain is extremely rugged — rocky, broken country with sheer cliffs and loose footing — interspersed with broad desert flats and deep sandy washes radiating outward from the mountains. The surrounding lowlands include King Valley to the north and the Colorado River basin desert to the west. Most of the unit interior is roadless wilderness requiring lengthy foot travel.

The entire unit lies within the Kofa National Wildlife Refuge (665,400 acres total across units 45A, 45B, and 45C), managed by the U.S. Fish and Wildlife Service. Approximately 547,719 acres (82%) of the refuge is designated Kofa Wilderness, where motorized travel is prohibited. Vehicle travel is restricted to designated roads only; off-road travel is not permitted anywhere in the unit. Refuge headquarters and visitor center are in Yuma at 9300 E. 28th Street (open Mon–Fri, 8 a.m.–4 p.m.). Key access points: U.S. Highway 95 is the primary corridor along the unit's western edge; the Castle Dome Road (Castle Dome Mine Road) provides about 9 miles of access into the southern unit from U.S. 95 near milepost 55; the King Road is a roughly 22-mile route through a gap in the Castle Dome Mountains connecting U.S. 95 to King Valley; the McPherson Pass Road connects Castle Dome to the Stone Cabin–King Valley Road and requires a high-clearance four-wheel-drive vehicle. Most refuge roads require four-wheel drive and high clearance; call the refuge at (928) 928-6873 for current conditions. No gas, drinking water, cell service, or towing services exist within the refuge. Nearest services are in Quartzsite (approximately 20 miles north) and Yuma (approximately 40 miles south). Temporary southern refuge closures may occur due to military activities.

Vegetation is classic lower Sonoran Desert scrub: palo verde, mesquite, catclaw acacia, and ironwood dominate the flats and lower slopes. Saguaro cactus, cholla, and ocotillo are common on alluvial fans and bajadas. Desert washes support denser riparian desert vegetation including desert willow. The mountains themselves feature rocky canyon habitat critical for bighorn sheep, with sparse desert shrubs on talus slopes. No pinyon-juniper, chaparral, or ponderosa pine is present — this is a uniformly hot, low-desert environment that frequently exceeds 120°F in summer.

Desert bighorn sheep (Mexicana subspecies) are the unit's signature species; the Kofa refuge bighorn herd was estimated at approximately 428 animals refugewide (2012 survey), with the herd having recovered from population lows around 2009. Mule deer (desert mule deer subspecies) are present throughout the unit's washes and flats, though herd density is low; populations have not recovered to historical levels due to drought and predation, and units 45A/B/C collectively carry some of the lowest desert mule deer densities in Arizona. Gambel's quail are present and can be excellent in wet years; populations are highly precipitation-dependent. Mountain lion hunting is not permitted on the refuge. Dove hunting is also not permitted. Non-game mammals include desert tortoise, kit fox, badger, coyote, ground squirrels, kangaroo rats, and pocket mice. Unexploded ordnance from WWII military exercises may be present in some areas.

1. Unit 45C is contained entirely within the Kofa National Wildlife Refuge (USFWS-managed), which imposes additional regulations beyond AZGFD rules — hunters must review current FWS Kofa public-use/hunt regulations before hunting. 2. Mule deer tag quota and unit-specific season hunt numbers for 2026 could not be confirmed from public sources; the AZGFD Commission Order is authoritative. 3. Bighorn sheep tag quota updated to 7 (4 early + 3 late) per GoHunt 2026 Arizona Application Strategy article; this reflects a tag increase from prior years. 4. Castle Dome Peak elevation corrected to 3,780 feet per Wikipedia Castle Dome Mountains article. 5. Bighorn sheep population estimate of 428 is from a 2012 refugewide survey per Wikipedia; more current data not available from public sources. 6. OTC archery deer status for 45C must be confirmed in real time at azgfd.gov/ArcheryDeerReport. 7. No elk, pronghorn, turkey, or javelina are present in this unit.