Unit 20 Unit 20
Desert mule deer, pronghorn and coveted desert bighorn wedged between I-25 and the missile range
South-central desert — Jornada, San Andres & Caballo ranges · Last reviewed 2026-07-12
Area
2,565
sq mi
Public land
—
approx.
Elevation
4,200–8,200
feet
Motorized
moderate
access
Overview
Unit 20 is a rugged strip of Chihuahuan desert squeezed between Interstate 25 on the west and the closed White Sands Missile Range on the east, running from near Las Cruces north to San Antonio. Its interior is dominated by the San Andres, Caballo and Fra Cristobal mountains rising out of the Jornada del Muerto basin. This is a low-density but high-quality desert unit: modest mule deer and pronghorn harvests, but home to some of New Mexico's most sought-after desert bighorn sheep draws in the Caballo and Fra Cristobal ranges.
Terrain
Broad Jornada del Muerto basin flanked by steep, rocky desert mountain ranges — the San Andres, Caballo and Fra Cristobal — that rise abruptly from creosote flats to rugged rimrock and canyon country.
Cover: Chihuahuan desert grassland and creosote/mesquite flats on the basin floor grading into juniper, sotol, ocotillo and scattered pinyon on the higher, rockier slopes.
Landmarks: San Andres Mountains · Caballo Mountains · Fra Cristobal Range · Jornada del Muerto · Caballo Lake · Elephant Butte Reservoir · White Sands Missile Range boundary
Access
Access is genuinely complicated. The White Sands Missile Range forms the eastern boundary and is closed to hunting, and the San Andres National Wildlife Refuge inside it is off-limits. Much of the Jornada is BLM and the Caballo Mountains are largely public BLM, but the Fra Cristobal Range sits on Ted Turner's private Armendaris Ranch (~360,000 acres, E-PLUS). The USDA Jornada Experimental Range is a restricted research area. Verify land status carefully — desert bighorn tags here are split between public (Caballo) and private-cooperative (Fra Cristobal) ground.
Managers: BLM, private ranch (E-PLUS), NM State Trust, USDA Jornada Experimental Range, White Sands Missile Range (closed)
Access points: I-25 frontage roads and exits (Caballo, Truth or Consequences, Engle) · NM-51 east from Truth or Consequences toward Engle · BLM two-tracks into the Jornada from the west · Caballo Lake State Park area for the Caballo Mountains
Species notes
Mule Deer
common opportunityDesert mule deer scattered through the mountain ranges and brushy foothills; densities are low and success rates run in the mid-20s, typical of arid southern units.
- →Glass the rocky slopes and canyon mouths of the San Andres and Caballo ranges at first and last light
- →Focus on the transition where creosote flats meet juniper/rimrock
- →Water sources and green draws concentrate deer in dry years
- →Be prepared to cover ground on foot — deer are thinly distributed
Pronghorn
limited qualityA small pronghorn population uses the open Jornada del Muerto grasslands; tags are few but success is fair when you draw.
- →Spot-and-stalk the open basin grasslands with a good spotting scope
- →Watch stock tanks and windmills mid-morning
- →Glass from high two-track vantage points across the flats
Bighorn Sheep
limited trophyDesert bighorn are the marquee draw here — restored herds in the Caballo Mountains (public) and Fra Cristobal Range (Armendaris Ranch) support special desert sheep permits that rank among the most coveted in the state.
- →These are once-in-a-lifetime draw tags — hire local knowledge or scout the rimrock exhaustively
- →Glass high, broken cliff bands and steep escape terrain
- →Focus on the rugged spines of the Caballo and Fra Cristobal ranges
Pro tips
- →Treat land-ownership research as job one — the mix of BLM, Armendaris (Turner) private, WSMR closure and state trust makes boundaries the deciding factor here
- →The Caballo Mountains offer the most accessible public desert-mountain hunting off Caballo Lake
- →Desert bighorn is the reason serious hunters chase this unit; put in for the draw and scout the Caballo/Fra Cristobal cliffs
- →Water is life for both game and hunters — map every tank, spring and windmill
- →Glass more, walk less; desert mule deer reward patient optics over ground-pounding
Watch out for
- !White Sands Missile Range (east boundary) and the San Andres NWR inside it are strictly closed — do not cross
- !The Fra Cristobal Range is private Armendaris Ranch (E-PLUS); most Fra Cristobal sheep access is cooperative, not open public
- !USDA Jornada Experimental Range is a restricted research area
- !Water is extremely scarce — carry far more than you think you need
- !Fire restrictions are common in dry desert years
Logistics
Truth or Consequences and Las Cruces bookend the unit with fuel, lodging and supplies, and I-25 runs the length of the west side making road access easy. The challenge is not getting near the unit but finding legal public ground within it — carry a current land-ownership layer and know exactly where BLM ends and the Armendaris/WSMR boundaries begin.
Nearest towns: Truth or Consequences, Elephant Butte, Caballo, Hatch, San Antonio, Las Cruces
Seasons & regulations
This page carries no season dates or regulations. Get current rules from the official New Mexico sources:
Research sources: NMDGF Game Management Unit 20 boundary map · Armendaris Ranch (Turner Enterprises) · GoHunt New Mexico Unit 20 profile
FAQ
- How big is Unit 20 in New Mexico?
- Unit 20 (Unit 20) covers about 2,565 square miles, ranging from roughly 4,200 to 8,200 feet in elevation. Area is computed from the unit boundary polygon.
- What species does the catalog list for Unit 20?
- Mule Deer, Pronghorn, Bighorn Sheep. For seasons, tags, and regulations, use the official New Mexico agency resources linked on this page — this page carries no regulatory information.
Put Unit 20 on your map.
Boundary lines, public/private ownership, topo, and offline maps for this unit — in Baseline Maps, free for 14 days.