GMU 36B Unit 36B — Tucson
Arizona's premier Coues density in the oak-grassland border mountains
Southern sky islands — Coronado NF (Atascosa & Pajarito ranges) · Last reviewed 2026-07-12
Area
564
sq mi
Public land
75%
approx.
Elevation
3,000–6,440
feet
Motorized
moderate
access
Overview
Unit 36B is one of Arizona's best-known Coues whitetail units, a border unit southwest of Tucson built around the Atascosa, Pajarito, San Luis and Tumacacori Mountains. It holds the highest whitetail density in the 36 complex and the largest share of ideal mountain-whitetail habitat, most of it inside the Coronado National Forest or the Buenos Aires National Wildlife Refuge — both open to public access. Deer is the marquee tag, dominated by Coues whitetail in the oak grassland and canyons, with desert mule deer along the lower mesquite country.
Terrain
Rolling mesquite hill country near 3,000' climbs into oak-grassland mountains cut by steep canyons; Atascosa Peak at ~6,440' is the high point. Classic sky-island relief packed into a compact range system.
Cover: Oak grassland and oak-juniper woodland on the slopes and in the canyons, with mesquite and semidesert grassland on the lower hills; sycamore-lined drainages in the deeper canyons.
Landmarks: Atascosa Mountains · Atascosa Peak · Pajarito Mountains · San Luis Mountains · Tumacacori Mountains · Sycamore Canyon · Peña Blanca Lake · Ruby Road (FR 39)
Access
The majority of the unit is Coronado National Forest, with the Buenos Aires NWR on the west side (open to hunting) and scattered State Trust land (recreation permit required). Ruby Road (FR 39) is the main east-west forest artery. This is a hard border unit — expect heavy Border Patrol presence and cross-border foot traffic, and avoid camping on obvious smuggling corridors.
Managers: USFS Coronado NF, USFWS Buenos Aires NWR, AZ State Trust, BLM, Private ranch
Access points: I-19 exits (Rio Rico, Nogales) · Ruby Road / FR 39 · AZ-289 (Peña Blanca Lake) · Arivaca Road · Sycamore Canyon trailhead
Species notes
Whitetail Deer
abundant qualityCoues whitetail are the headline here — 36B carries the highest whitetail density of the 36 units, concentrated in the oak grassland and canyons of the Atascosa, Pajarito, San Luis and Tumacacori Mountains.
- →Glass oak-covered slopes and canyon heads from a tripod at dawn and dusk
- →Hunt the oak-grassland ecotone between roughly 4,000 and 6,000 feet
- →Time the general rifle hunt to the late-season rut when bucks chase does into the open
- →Get above the deer at first light and pick apart shaded north faces
Mule Deer
limited opportunityDesert mule deer occupy the lower mesquite hills and grassland margins, secondary to the abundant Coues whitetail.
- →Glass mesquite flats and washes on the lower fringes early
- →Check open grassland benches away from the oak country
- →Confirm species where mule deer and Coues overlap
Pro tips
- →This is a glassing unit first and foremost — a good tripod-mounted binocular is worth more than miles of walking
- →Concentrate on the oak-grassland transition in the Atascosa and Pajarito ranges for the highest Coues numbers
- →Time your hunt to the rut for the best odds at a mature buck
- →Base out of Peña Blanca Lake or along Ruby Road for central access to the best country
- →Carry a State Trust land recreation permit for the checkerboard parcels
Watch out for
- !Active international border: heavy Border Patrol presence and cross-border foot traffic — carry ID and avoid smuggling corridors
- !State Trust land requires a recreation permit; private ranches are interspersed with public
- !Steep canyon country — plan retrieval before you shoot
- !Water is limited off the drainages and lake; pack your own
- !Forest roads turn treacherous after rain and fire restrictions are common in the dry season
Logistics
Nogales and Rio Rico along I-19 offer full services and easy staging; Arivaca is a small outpost on the west side. Ruby Road and forest spurs range from graded dirt to rough high-clearance tracks and get slick when wet. Peña Blanca Lake is a handy central landmark and camp base. Cell coverage fades quickly in the canyons.
Nearest towns: Nogales, Rio Rico, Tumacacori, Arivaca
Seasons & regulations
This page carries no season dates or regulations. Get current rules from the official Arizona sources:
Research sources: AZGFD GMU 36B · Chasen the King — Unit 36 A/B/C Coues Overview · CouesWhitetail.com — Unit 36B
FAQ
- How big is GMU 36B in Arizona?
- GMU 36B (Unit 36B — Tucson) covers about 564 square miles, ranging from roughly 3,000 to 6,440 feet in elevation. Area is computed from the unit boundary polygon.
- How much public land is in GMU 36B?
- Approximately 75% of the unit is public land. Primary managers: USFS Coronado NF, USFWS Buenos Aires NWR, AZ State Trust, BLM, Private ranch. Always verify ownership boundaries on the ground.
- What species does the catalog list for GMU 36B?
- Whitetail Deer, 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 36B on your map.
Boundary lines, public/private ownership, topo, and offline maps for this unit — in Baseline Maps, free for 14 days.