Colorado GMU 23 Pronghorn Hunting
Rio Blanco and Garfield counties, northwest Colorado · 423 sq mi
EVERY pronghorn hunt code in this unit is private-land-only. There is no unit-wide public hunt here of any sex — not buck, not either-sex, and not antlerless — so the public land inside this unit is not open to pronghorn hunting under any of these codes. A private-land-only license is drawn through the public draw, but it is valid only on private ground, and the hunter must arrange their own permission to hunt there — CPW does not provide access with the license. Do not describe private-land-only ground as "enrolled": enrollment is what Ranching for Wildlife ranches do.
What hunting GMU 23 is like
GMU 23 spans 423 square miles across Rio Blanco and Garfield counties in the northwestern part of the state. The unit is rolling to moderately steep, with 47 percent of its terrain gentle, 38 percent moderate, and 15 percent steep. Elevations range from 6,100 feet at the low end to 10,100 feet at the high end, with typical elevations around 7,800 feet. The varied topography creates diverse pronghorn habitat across the unit's extent.
Approximately 45 percent of GMU 23 is open to public hunting, comprising roughly 189 square miles managed by the U.S. Forest Service, Bureau of Land Management, and state wildlife areas. The remaining 55 percent is privately owned. Hunters interested in accessing public ground will need to investigate specific roads, trailheads, and seasonal closures, as ownership alone does not guarantee easy entry to all mapped public acreage.
Pronghorn overall range covers 24 percent of the unit, while a winter range is mapped across 4 percent. The seasonal range distribution indicates that pronghorn use portions of the unit across the fall period, though the relatively small winter range share means that ground holds only part of the pronghorn population during the colder months.
The only pronghorn season offered in GMU 23 is private-land-only, running September 19 through October 4 for does and bucks. This hunt falls during the primary rut and late rut phases. Since this license is valid only on private ground, public-land hunters cannot pursue pronghorn under any of the draw codes offered in this unit. Those seeking to hunt here must arrange permission with private landowners. September conditions typically bring highs near 72 degrees Fahrenheit and lows near 43 degrees, while October temperatures cool to highs around 59 degrees and lows around 32 degrees, with roughly 1.2 inches of monthly snowfall possible by late October.
Terrain & elevation
- Elevation
- 6,100–10,100 ft, typically around 7,800 ft
- Steepness
- Steep — mean slope 13.3°
- Slope breakdown
- 47% gentle · 38% moderate · 15% steep · 0% rugged
- Ground you can count on
- ~189 sq mi
Habitat & cover
What actually grows here, by elevation. Each band adds to 100% on its own — these are shares of that band, not of GMU 23.
Lower elevations
- Sagebrush47%
- Other cover23%
- Aspen18%
- Conifer10%
- Riparian2%
Mid elevations
- Aspen66%
- Sagebrush23%
- Conifer9%
- Other cover1%
Higher elevations
- Aspen59%
- Conifer23%
- Sagebrush16%
- Grass and meadow1%
Cover classes from the USGS National Land Cover Database, split into elevation bands. “Other cover” is the remainder of the classification — bare ground, water, agriculture and developed land — and is left unnamed rather than guessed at.
Land & access
About 45% of GMU 23 is public land a hunter can count on — National Forest, BLM and State Wildlife Areas.
- National Forest32%
- BLM8%
- State Wildlife Area5%
- Private55%
Where pronghorn live in the unit
Colorado Parks & Wildlife maps pronghorn seasonal ranges statewide. This is how much of GMU 23 each range covers — the single best clue to whether pronghorn are here in September, in November, or only passing through. The layers overlap, so they do not add to 100%.
- Overall Range24%the full extent of range CPW maps for pronghorn — near 100% on most units, and not a statement about when pronghorn are present
- Winter Range4%used in winter
Pronghorn seasons & weapons (2026)
| Season | Dates | Tags offered |
|---|---|---|
| Private-land only | September 19 – October 4 | Doe, Buck |
Dates span every hunt code of that type in this unit and can differ by code. Confirm the current brochure with Colorado Parks & Wildlife before applying.
Fall weather
- September — highs around 72°F, lows around 43°F (mid-elevation normals)
- October — highs around 59°F, lows around 32°F, about 1.2 in of snow (mid-elevation normals)
- November — highs around 45°F, lows around 22°F, about 6.2 in of snow (mid-elevation normals)
GMU 23 pronghorn hunting FAQ
Is there any pronghorn hunting available to public-land hunters in GMU 23?
No. The sole pronghorn season offered in this unit is private-land-only, valid only on private ground. Public-land hunters cannot pursue pronghorn under any draw code here. Hunters interested in this unit must secure their own permission on private land.
How much ground can a hunter actually access for pronghorn?
Since the only available season is private-land-only, hunters are limited to private ground where they have secured permission. The 189 square miles of public land in the unit is not open to pronghorn hunting under the offered licenses.
When does the rut occur and how does that relate to the season?
The pronghorn primary rut runs from September 6 to September 25, and the late rut extends from September 26 to October 15. The season here falls within both phases, spanning September 19 through October 4, placing hunters in active rut conditions for the first portion of the hunt and post-rut conditions toward the end.
What are the weather conditions during the season?
September offers pleasant conditions with highs near 72 degrees Fahrenheit and lows near 43 degrees, with negligible snowfall. By October, temperatures drop significantly to highs around 59 degrees and lows around 32 degrees, with roughly 1.2 inches of snowfall possible mid-month and beyond.
What does the terrain look like for hunting on foot?
The unit is rolling to moderately steep, with nearly half the ground being gentle terrain, making it reasonably navigable. The other half splits between moderate and steep slopes, so hunters should expect mixed conditions depending on where they access private land.
How much of the unit do pronghorn actually occupy?
Overall pronghorn range covers 24 percent of the unit, and a winter range is mapped across 4 percent. This indicates pronghorn are present across portions of the unit through the fall, though they do not occupy the entire area uniformly.
Data sources & methodology
- Colorado Parks & Wildlife — Big Game hunting — seasons, weapons, hunt codes and license types
- CPW — Primary Draw rules — how preference points and the hybrid draw work
- CPW — Pronghorn statistics, draw recap and Drawn Out At reports — the point levels behind the draw-difficulty bands
- CPW — Secondary Draw — licenses remaining after the primary draw
- USGS / MRLC — National Land Cover Database — habitat and cover classes by elevation band
- CPW — Maps and GIS (Species Activity Mapping) — pronghorn seasonal range
- CPW — State Trust Land Finder — which State Trust acreage is enrolled and open to public hunting
- USGS PAD-US — Protected Areas Database of the United States — land ownership and access
- Daymet daily climate, 1991–2020 (Oak Ridge National Laboratory) — fall weather
Draw difficulty is a qualitative band, not published odds — the note under the summary above states exactly which hunt code it describes. Land shares are separate, non-overlapping categories: publicly owned is not the same as open to hunting, and State Trust Land is huntable only where CPW has enrolled it. Unit data last updated September 24, 2026.