GMU 78 GMU 78 — Archuleta/Conejos/Mineral/Rio Grande Co.
Big, wild South San Juan country from oak-brush foothills to Continental Divide alpine
South-central Colorado — South San Juan Wilderness east of Pagosa Springs · Last reviewed 2026-07-12
Area
765
sq mi
Public land
62%
approx.
Elevation
6,500–13,150
feet
Motorized
moderate
access
Overview
GMU 78 is a large (roughly 765-square-mile), rugged unit spanning the South San Juan Wilderness between Pagosa Springs and the Continental Divide, bounded south by the New Mexico line. It is classic San Juan / Rio Grande National Forest deer, elk, and bear country with a mix of San Juan and Rio Grande NF ground and a large over-the-counter elk component — archery and the 2nd and 3rd rifle seasons are OTC for bulls, while mule deer is fully limited-draw. A tiny pronghorn presence exists on the lower open country. This is one of the region's better big-game units, hunted from roadside camps up to horseback pack-ins.
Terrain
Massive vertical relief from oak-brush foothills near 7,000 feet up through aspen and dark timber to alpine meadows and Continental Divide peaks above 13,000 feet. The South San Juan Wilderness fills the high, roadless heart of the unit.
Cover: Gambel oak and mountain shrub on the foothills, aspen and mixed conifer (spruce-fir) through the mid and upper slopes, and open alpine tundra and meadows above timberline.
Landmarks: South San Juan Wilderness · Continental Divide · Navajo River · Blanco River · Chromo · Cumbres Pass area · Rio Grande National Forest · San Juan National Forest
Access
Roughly 62% public across San Juan and Rio Grande NF, with the South San Juan Wilderness anchoring the high country. Private ranchland dominates the lower valley bottoms near Chromo and along the Navajo and Blanco rivers — know those boundaries. Colorado State Trust lands are NOT open to hunting unless enrolled in CPW's Public Access Program. The wilderness core is foot- or horseback-only; forest roads reach the mid-country trailheads.
Managers: USFS Rio Grande National Forest, USFS San Juan National Forest, BLM, private ranch
Access points: US 84 south toward Chromo · Navajo River Road / Blanco Basin Road · Buckles Lake / South San Juan Wilderness trailheads · US 160 east of Pagosa Springs
Species notes
Rocky Mountain Elk
common opportunityA strong, well-distributed elk herd and the unit's biggest harvest, with a large OTC component — archery and 2nd/3rd rifle bull tags are over-the-counter. Success runs around 20%, good for OTC country, and the third rifle season can align with lingering rut activity in the high timber.
- →Bugle the dark-timber and aspen benches below the Continental Divide during the September rut.
- →For OTC rifle, pack toward the South San Juan Wilderness edge to escape road-hunting pressure.
- →Hunt timber-to-meadow transitions and north-facing dark timber where pressured bulls hold midday.
Mule Deer
common qualityA quality limited-draw deer unit that filled nearly half its tags recently. Bucks use the oak-brush and aspen benches, dropping toward the valleys with snow. The South San Juan's mix of habitat grows respectable bucks for hunters who get off the roads.
- →Glass oak-brush foothills and aspen edges at first and last light.
- →Later seasons: intercept bucks migrating down off the high country toward the Navajo and Blanco drainages.
- →Spot-and-stalk the timber benches rather than road-hunting the valley corridors.
Black Bear
common opportunityThe South San Juan is top-tier black bear country, and GMU 78's oak-brush and aspen mix is prime fall habitat. A solid opportunity, most often taken by deer and elk hunters during the fall overlap.
- →Hunt Gambel-oak and berry pockets on south and east slopes during a good mast year.
- →Glass avalanche chutes and aspen edges at first and last light.
- →Work oak-brush benches near water on warm early-season days.
Pronghorn
limited opportunityA very thin pronghorn presence on the lower open ground — a handful of tags and tiny harvest. This is an incidental, hard-to-draw bonus, not a reason to pick the unit.
- →Focus the open sage and grassland flats on the lower end of the unit.
- →Glass long from two-tracks and use terrain to close the distance.
- →Treat it as a bonus tag paired with big-game scouting.
Pro tips
- →The high country and South San Juan Wilderness hold the best age class — plan a pack-in, not a road hunt.
- →Third rifle can catch lingering rut activity in the high timber; still-hunt the dark timber.
- →Watch private ranch boundaries in the Chromo, Navajo, and Blanco valley bottoms.
- →Time archery to the rut and work the aspen/dark-timber transitions below the Divide.
Watch out for
- !Private ranchland dominates the valley bottoms near Chromo and along the Navajo/Blanco rivers.
- !OTC-rifle crowding near the main trailheads.
- !State Trust lands are closed to hunting unless in CPW's Public Access Program.
- !Early snow and fall storms can close high forest roads and strand vehicles.
Logistics
Pagosa Springs to the west is the primary services town — fuel, groceries, lodging, outfitters; Chama, New Mexico and Antonito lie to the south and east. The mid-country is reachable by forest road to trailheads at Blanco Basin, Navajo River, and Buckles Lake, but the wilderness core demands a foot or horseback pack-in. High-clearance 4WD is strongly recommended, and fall storms can close the higher roads. Cell service is unreliable off the highways — carry a satellite communicator.
Nearest towns: Pagosa Springs, CO, Chromo, CO, Antonito, CO, Chama, NM
Seasons & regulations
This page carries no season dates or regulations. Get current rules from the official Colorado sources:
Research sources: CPW Big Game Hunting / GMU information · GOHUNT Colorado Unit 78 profile · Backcountry Chronicles — Colorado OTC elk units · Rio Grande / San Juan National Forests (USFS)
FAQ
- How big is GMU 78 in Colorado?
- GMU 78 (GMU 78 — Archuleta/Conejos/Mineral/Rio Grande Co.) covers about 765 square miles, ranging from roughly 6,500 to 13,150 feet in elevation. Area is computed from the unit boundary polygon.
- How much public land is in GMU 78?
- Approximately 62% of the unit is public land. Primary managers: USFS Rio Grande National Forest, USFS San Juan National Forest, BLM, private ranch. Always verify ownership boundaries on the ground.
- What species does the catalog list for GMU 78?
- Rocky Mountain Elk, Mule Deer, Black Bear, Pronghorn. For seasons, tags, and regulations, use the official Colorado agency resources linked on this page — this page carries no regulatory information.
Put GMU 78 on your map.
Boundary lines, public/private ownership, topo, and offline maps for this unit — in Baseline Maps, free for 14 days.