GMU 42 Unit 42 — Yuma, Mesa
Sonoran desert plains and steep desert ranges west of Phoenix — a reestablished bighorn hunt and low-density trophy muleys.
West-of-Phoenix desert — Harquahala, Harcuvar & Big Horn ranges · Last reviewed 2026-07-12
Area
1,491
sq mi
Public land
85%
approx.
Elevation
400–5,680
feet
Motorized
moderate
access
Overview
Unit 42 sits in the desert west of Phoenix, its terrain ranging from low, wash-cut desert plains up to rugged high-desert ranges — the Harquahala, Harcuvar, Big Horn and Vulture mountains. Desert bighorn were reestablished here through transplants, and the population has grown enough that a sheep hunt returned in 2013, with the Big Horn Mountains holding most of the sheep and rams pushing into the 170-inch class. Desert mule deer live in low numbers but include some mature bucks, most vulnerable during the winter muzzleloader and late archery seasons. Hunting is on BLM and Arizona State Trust land, with generally moderate hiking but serious heat.
Terrain
Low Sonoran desert plains cut by numerous washes rising to high desert mountain ranges, topping out at Harquahala Peak (~5,680 ft). Steep, rocky ranges surrounded by broad bajadas.
Cover: Lowland Sonoran desert scrub — creosote, cactus, ironwood and paloverde; desert grasslands with mesquite at middle and higher elevations on the ranges.
Landmarks: Harquahala Mountains / Harquahala Peak · Harcuvar Mountains · Big Horn Mountains · Vulture Mountains · Centennial Wash
Access
Hunting is on BLM and Arizona State Trust lands, which cover most of the unit; State Trust parcels require an Arizona recreation permit. The Big Horn Mountains and Harquahala Mountains hold BLM Wilderness areas where travel is foot/horse only (no vehicles or mechanized transport). Scattered private ranch and ag ground exists — check boundaries. Access via I-10, US 60 and BLM dirt roads is generally good to the range bases.
Managers: BLM, AZ State Trust, Private (scattered ranch/ag)
Access points: Interstate 10 (Tonopah, Salome Road exits) · US 60 (Wickenburg–Aguila–Salome corridor) · BLM roads to the Harquahala, Harcuvar and Big Horn range bases · Eagle Eye Road / Centennial Wash routes
Species notes
Bighorn Sheep
limited trophyA success story — transplanted desert bighorn grew enough to reopen a hunt in 2013, with the Big Horn Mountains holding most of the sheep and rams taken in the 170-inch range. A rare once-in-a-lifetime tag with effectively 100% success.
- →Concentrate on the Big Horn Mountains, which hold the bulk of the sheep
- →Glass rocky faces, saddles and rimrock at first and last light
- →Key on water and shaded bedding in the desert heat
- →Scout ranges from the flats with high-power optics before climbing
Mule Deer
limited opportunityLow numbers of desert mule deer, but some mature bucks are present. They're most vulnerable during the winter muzzleloader and late archery seasons; success runs low (~25%).
- →Hunt the winter muzzleloader and late archery windows when bucks are most vulnerable
- →Glass the desert plains, washes and lower range flanks from high points
- →Work the numerous washes where deer feed and shade up
- →Cover ground and be patient — deer are scattered and low-density
Pro tips
- →For sheep, focus the Big Horn Mountains — they hold most of the unit's bighorn and produce rams near 170 inches.
- →Time deer hunts to the winter muzzleloader or late archery seasons when mature bucks drop their guard.
- →Carry plenty of water — heat, not terrain, is the limiting factor here.
- →Respect the BLM Wilderness in the Big Horn and Harquahala ranges — foot/horse access only.
- →Verify State Trust and scattered private boundaries before you set up.
Watch out for
- !State Trust parcels require an Arizona State Land recreation permit.
- !Big Horn and Harquahala Mountains include BLM Wilderness — no vehicles/mechanized travel, foot or horse only.
- !Desert heat is the main hazard — carry ample water.
- !Scattered private ranch/ag ground — check boundaries.
- !Spotty cell service and soft sand on BLM roads — carry recovery gear and extra fuel.
Logistics
Wickenburg is the main services hub (fuel, lodging, groceries); Aguila, Salome, Wenden and Tonopah offer fuel and basics, with the Phoenix metro close on the east. Hiking is generally not strenuous, but heat is the main hazard — carry ample water. Bring recovery gear and extra fuel for the BLM dirt roads; cell coverage is spotty away from the highways.
Nearest towns: Wickenburg, Aguila, Salome, Wenden, Tonopah
Seasons & regulations
This page carries no season dates or regulations. Get current rules from the official Arizona sources:
Research sources: AZGFD GMU 42 · Unit 42 - Hunt Now Arizona · Arizona Unit 42 Profile - GoHunt
FAQ
- How big is GMU 42 in Arizona?
- GMU 42 (Unit 42 — Yuma, Mesa) covers about 1,491 square miles, ranging from roughly 400 to 5,680 feet in elevation. Area is computed from the unit boundary polygon.
- How much public land is in GMU 42?
- Approximately 85% of the unit is public land. Primary managers: BLM, AZ State Trust, Private (scattered ranch/ag). Always verify ownership boundaries on the ground.
- What species does the catalog list for GMU 42?
- Bighorn Sheep, Mule Deer. For seasons, tags, and regulations, use the official Arizona agency resources linked on this page — this page carries no regulatory information.
Put GMU 42 on your map.
Boundary lines, public/private ownership, topo, and offline maps for this unit — in Baseline Maps, free for 14 days.