Unit 36C, Arizona

Elevation ranges from approximately 3,000 feet on the flat Altar Valley floor to 7,734 feet at Baboquivari Peak on the western edge (the unit high point). The landscape transitions sharply from nearly level desert grassland and mesquite flats in the east and center to steep, rocky mountain canyons and ridges in the west. Numerous washes and drainage channels cross the valley. Total unit area is approximately 315 square miles (201,600 acres). The unit boundary runs south along AZ 286 to the U.S.-Mexico border at Sasabe, west along the border to the Tohono O'odham Reservation, then north along the reservation boundary to AZ 86.

Primary access is via Arizona State Route 286, which runs north-south through the Altar Valley for the full length of the unit. The north end intersects AZ 86 at Three Points. Key landmarks along AZ 286 include Buenos Aires NWR Headquarters at approximately milepost 7.7, Elkhorn Ranch at approximately milepost 25.2, and Kings Anvil Ranch at approximately milepost 37.7. Buenos Aires NWR comprises 23.28 square miles within unit 36C; approximately 89 percent of the refuge (105,113 acres) is open to hunting, accessible via a network of maintained dirt roads. High-clearance vehicles are strongly recommended; motorized travel is restricted to designated refuge roads. No Hunt Zones include Brown Canyon, the headquarters area, Pronghorn Drive auto tour loop, and areas within one quarter mile of refuge residences. Trapping and pursuit with dogs are prohibited on BANWR. The Baboquivari Peak Wilderness (2,065 acres, BLM) lies along the western edge; foot access only. Non-tribal visitors require a permit from the Tohono O'odham Nation to access the reservation side of the Baboquivari Mountains. The Tohono O'odham Nation reservation occupies terrain west of the mountain crest and is closed to non-tribal hunting. State Trust land makes up a significant portion of the unit and requires a valid Arizona hunting or fishing license or a State land permit for access. Commission Note 129: Pima County-owned ranches Kings 98 Ranch, Old Hayhook Ranch, and Verdugo within 36C are open to hunting. Commission Note 22: City of Tucson Duval property in 36C is open to foot-access hunting only at designated entry points with mandatory sign-in. Mandatory sign-in/sign-out is required at each individual ranch; signing in at one does not permit access to others. No developed campgrounds exist within the unit; Buenos Aires NWR offers one group campsite (used for AZGFD mentored hunts). The unit is a known corridor for unauthorized border crossings; hunters should carry identification and exercise caution. Public land is approximately 81 percent of the unit.

Lower elevations (3,000–4,500 ft) are dominated by Sonoran desert scrub interspersed with dense mesquite grassland, saguaro, palo verde, ocotillo, and cholla. The semi-desert grassland of the Altar Valley is the primary landscape, managed in large part as Buenos Aires NWR. Mid-elevation slopes support ocotillo thickets transitioning to chaparral on rocky hillsides. North-facing drainages and canyons at higher elevations carry oak woodland with Emory and shrub live oaks. The Buenos Aires NWR was established specifically to restore habitat for the endangered masked bobwhite quail.

Coues white-tailed deer are the flagship game species; habitat concentrates along the Baboquivari foothills on the western boundary, where rocky slopes, north-facing drainages, and oak pockets provide thermal cover. Bucks use south-facing slopes in the morning and shift to north-facing slopes in the afternoon. Ocotillo thickets are productive buck habitat. Mule deer occupy the lower mesquite grassland and desert flats of the central and eastern Altar Valley; glassing from Buenos Aires NWR roads is an effective locating strategy. Javelina maintain a strong, wide-ranging population throughout the Baboquivari canyons and across the mesquite-dominated flats; they are found at essentially all elevations within the unit and are best spotted by glassing east-facing slopes at first light. Mountain lion are present year-round following deer populations into the Baboquivaris. Coyote, bobcat, coati, gray fox, ringtail, badger, and skunk are present. Buenos Aires NWR supports reintroduced masked bobwhite quail (endangered, not a game species) along with Gambel's and scaled quail. Mourning dove and white-winged dove are seasonally abundant. Cottontail and black-tailed jackrabbit are common. Occasional jaguar movement through the unit has been documented; jaguars are federally protected under the Endangered Species Act. No elk, pronghorn, or bighorn sheep are present or hunted in the unit. Quail hunters should note that masked bobwhite quail may be present outside BANWR boundaries — these birds are federally protected.