Colorado GMU 131 Pronghorn Hunting
Routt and Rio Blanco counties, northwest Colorado · 193 sq mi
This unit offers no unit-wide buck or either-sex pronghorn hunt open across the unit. Public applicants can draw antlerless tags here. Private-land-only and Ranching for Wildlife licenses are drawn by Colorado residents through the public draw, but neither is unit-wide: a private-land-only license needs permission on private ground, and a Ranching for Wildlife license is valid on the ranches enrolled in that program.
What hunting GMU 131 is like
Colorado GMU 131 occupies 193 square miles across the northwestern corner of the state in Routt and Rio Blanco counties. The unit is rolling, with some steeper breaks, spanning from 6,500 feet to 9,100 feet elevation. Terrain across the unit is 51 percent gentle, 39 percent moderate, and 10 percent steep, making it walkable country for hunters on foot across much of its area.
The unit is approximately 82 percent private land. Public hunting is limited to about 11 percent of the unit: roughly 21 square miles of BLM, National Forest, and State Wildlife Areas. An additional 5.5 percent is Colorado State Trust Land, huntable only where CPW has enrolled parcels in the Public Access Program. Approximately 1.6 percent is unclassified in ownership. Private ground dominates the landscape, and while the rolling terrain is generally accessible on foot, legal entry is the primary constraint for public hunters.
CPW's mapping shows Overall Range covering 22 percent of the unit, indicating where pronghorn may be found across the unit. Pronghorn in this area respond to elevation, terrain, and the character of available forage, with animals distributed across the mapped range rather than concentrated in a single zone throughout the fall.
The unit offers three seasons: an Archery season from August 15 through September 20 and a Muzzleloader season from September 21 through September 29, both open to public applicants for buck antelope. A third season, October 3 through October 11, is private-land only. The draw is for antlerless opportunities. Temperatures in September average highs near 71 degrees and lows near 39 degrees with minimal precipitation. October brings cooling to average highs near 57 degrees, and November drops significantly to highs averaging 43 degrees with 10 inches of snowfall. Overall hunter pressure in the unit is high.
Terrain & elevation
- Elevation
- 6,500–9,100 ft, typically around 7,300 ft
- Steepness
- Moderate — mean slope 12°
- Slope breakdown
- 51% gentle · 39% moderate · 10% steep · 0% rugged
- Ground you can count on
- ~21 sq mi, plus ~11 sq mi of State Trust Land where access depends on enrollment
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 131.
Lower elevations
- Sagebrush62%
- Other cover19%
- Aspen12%
- Riparian4%
- Grass and meadow2%
- Conifer1%
Mid elevations
- Aspen54%
- Sagebrush38%
- Other cover4%
- Conifer3%
- Grass and meadow2%
Higher elevations
- Aspen64%
- Sagebrush25%
- Conifer8%
- Other cover3%
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 11% of GMU 131 is public land a hunter can count on — BLM, State Wildlife Areas and National Forest. A further 5% is State Trust Land, which is huntable only where CPW has enrolled it.
- BLM9%
- State Wildlife Area1%
- National Forest<1%
- State Trust Land5%
- Unclassified ownership2%
- Private82%
Colorado State Trust Land is open to public hunting only where it is enrolled in CPW's Public Access Program. Check current enrollment before planning around it.
“Ownership unclassified” means the source dataset does not record an owner for that acreage. It is not known to be public or private.
Where pronghorn live in the unit
Colorado Parks & Wildlife maps pronghorn seasonal ranges statewide. This is how much of GMU 131 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 Range22%the full extent of range CPW maps for pronghorn — near 100% on most units, and not a statement about when pronghorn are present
Pronghorn seasons & weapons (2026)
| Season | Dates | Tags offered |
|---|---|---|
| Archery | August 15 – September 20 | Buck |
| Muzzleloader | September 21 – September 29 | Buck |
| Private-land only | October 3 – October 11 | 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 71°F, lows around 39°F (mid-elevation normals)
- October — highs around 57°F, lows around 29°F, about 2.1 in of snow (mid-elevation normals)
- November — highs around 43°F, lows around 19°F, about 10 in of snow (mid-elevation normals)
GMU 131 pronghorn hunting FAQ
How much ground can a public-land hunter actually hunt here?
About 11 percent of the unit, or roughly 21 square miles, is generally open to public hunting and includes BLM, National Forest, and State Wildlife Areas. An additional 5.5 percent is State Trust Land, but access depends on whether CPW has enrolled specific parcels in the Public Access Program. The remaining 82 percent is private land. Legal access, not terrain walkability, is the main limiting factor for public hunters in this unit.
What does this antlerless-only draw mean?
The unit offers no unit-wide buck or either-sex pronghorn hunt open to public applicants. Public hunters may draw antlerless tags here. Private-land-only and Ranching for Wildlife licenses are also available through the public draw but require permission or enrollment on private ground and are not unit-wide hunts.
Does the Archery season fall during the rut?
The Archery season runs August 15 through September 20 and overlaps both the Pre-Rut / Territory Formation phase (through September 5) and the Primary Rut (September 6–25). The season thus spans from pre-rut activity into active rut conditions.
When should a hunter expect the coldest conditions and snow?
September and early October are mild and mostly dry. October cools to highs near 57 degrees, and November brings a significant drop to highs around 43 degrees with 10 inches of average snowfall. Hunters planning for late seasons should prepare for cold and snow.
Is there a Muzzleloader season, and when does it occur?
Yes, a Muzzleloader season runs September 21 through September 29, falling in the Primary Rut and early Late Rut phases. This season is open to public applicants for buck antelope and comes after the Archery season closes.
Why is the draw listed as 'high' pressure if it's antlerless only?
Draw difficulty and hunter pressure are separate measures. High pressure refers to the overall number of hunters on the ground, not draw competitiveness. Antlerless-only hunts can still attract significant applicant numbers and competition for tags, making pressure high even though the specific harvest opportunity differs from unit-wide buck seasons.
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.