Colorado GMU 171 Mule Deer Hunting
Jackson County, northwest Colorado · 256 sq mi
Based on the EASIEST unit-wide buck or either-sex hunt code available to adult Colorado residents in the 2026 primary draw — the lowest preference-point tier that drew reliably. Private-land-only and Ranching for Wildlife hunts are excluded because neither is a unit-wide public-land opportunity — NOT because the public cannot draw them. A private-land-only license requires the hunter's own permission to hunt private ground; a Ranching for Wildlife license is valid on the participating ranches enrolled in that program. They are separate systems. Other weapons, seasons and nonresident applicants can require substantially more points. The band is a floor, not a target: even the easiest qualifying hunt here sits in that range.
What hunting GMU 171 is like
GMU 171 occupies 256 square miles of northwestern Colorado in Jackson County, ranging from 8,000 feet to 12,900 feet in elevation. The terrain is rolling, with some steeper breaks. Gentle slopes dominate at 69 percent of the unit's area, while moderate slopes cover 23 percent. Steep terrain makes up 7 percent and rugged terrain 1 percent, giving the unit a mean slope of 8.4 degrees.
Roughly half the unit is generally open to public hunting: about 52 percent (134 square miles) is National Forest, BLM, and State Wildlife Areas. An additional 3.5 percent is Colorado State Trust Land, huntable only where CPW has enrolled it in the Public Access Program. Private land covers approximately 37 percent of the unit, and ownership of 7.6 percent is unclassified in the source data. Public land ownership totals roughly 56 percent when trust land is included, but the openly huntable share remains the 52 percent figure.
Mule deer occupy summer range across the unit's full 100 percent and are mapped across the full extent of overall range. Winter range covers only 7 percent of the unit, and winter concentration—ground where mule deer cluster—marks just 2 percent. Migration corridors occupy 5 percent. This distribution means mule deer are concentrated on a limited portion of the unit during winter months, with the bulk of the population dispersed across summer range through the early fall. A hunter should expect seasonal shift toward winter ground as the season advances, though timing and extent vary with weather and snow.
GMU 171 offers seven mule deer seasons across three weapons. Archery runs September 2 to September 30 as either-sex hunting. Muzzleloader follows September 12 to September 20 for doe and buck. Early Rifle runs October 1 to October 7 as either-sex. Four numbered rifle seasons then run consecutively: 1st Rifle October 14 to October 18 (buck), 2nd Rifle October 24 to November 1 (buck), 3rd Rifle November 7 to November 15 (buck), and 4th Rifle November 18 to November 22 (buck). Archery and muzzleloader occur during the velvet-shed and early-fall transition phase. Early Rifle coincides with early-fall migration and nocturnal buck activity. The first two numbered rifle seasons also span this migration phase, while 2nd Rifle extends into early pre-rut staging. 3rd Rifle spans early pre-rut through the primary rut, and 4th Rifle falls entirely within the primary rut period. Fall temperatures cool steadily from September highs near 65 degrees Fahrenheit to November highs near 39 degrees, with October snowfall averaging 4.4 inches and November averaging 12.9 inches. The unit experiences extreme hunter pressure and draws at easy difficulty, often at zero preference points for the most accessible unit-wide buck or either-sex hunt code available to adult Colorado residents.
Terrain & elevation
- Elevation
- 8,000–12,900 ft, typically around 8,800 ft
- Steepness
- Gentle — mean slope 8.4°
- Slope breakdown
- 69% gentle · 23% moderate · 7% steep · 1% rugged
- Ground you can count on
- ~134 sq mi, plus ~9 sq mi of State Trust Land where access depends on enrollment
Land & access
About 52% of GMU 171 is public land a hunter can count on — National Forest, BLM and State Wildlife Areas. A further 3% is State Trust Land, which is huntable only where CPW has enrolled it.
- National Forest38%
- BLM14%
- State Wildlife Area<1%
- State Trust Land3%
- National Park Service<1%
- Unclassified ownership8%
- Private37%
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 mule deer live in the unit
Colorado Parks & Wildlife maps mule deer seasonal ranges statewide. This is how much of GMU 171 each range covers — the single best clue to whether mule deer are here in September, in November, or only passing through. The layers overlap, so they do not add to 100%.
- Summer Range100%used in summer
- Overall Range100%the full extent of range CPW maps for mule deer — near 100% on most units, and not a statement about when mule deer are present
- Winter Range7%used in winter
- Migration Corridors5%movement between ranges, not residence
- Winter Concentration2%where mule deer bunch up in winter
Mule Deer seasons & weapons (2026)
| Season | Dates | Tags offered |
|---|---|---|
| Archery | September 2 – September 30 | Either-sex |
| Muzzleloader | September 12 – September 20 | Doe, Buck |
| 1st Rifle | October 14 – October 18 | Buck |
| 2nd Rifle | October 24 – November 1 | Buck |
| 3rd Rifle | November 7 – November 15 | Buck |
| 4th Rifle | November 18 – November 22 | Buck |
| Early Rifle | October 1 – October 7 | 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 65°F, lows around 35°F, about 0.3 in of snow (mid-elevation normals)
- October — highs around 52°F, lows around 26°F, about 4.4 in of snow (mid-elevation normals)
- November — highs around 39°F, lows around 16°F, about 12.9 in of snow (mid-elevation normals)
GMU 171 mule deer hunting FAQ
Is there realistic public hunting ground here, or is most of it private?
About 52 percent of the unit—roughly 134 square miles across National Forest, BLM, and State Wildlife Areas—is generally open to public hunting. Another 3.5 percent is State Trust Land, huntable only where CPW has enrolled it. Private land covers 37 percent of the unit. A hunter planning public-land access has a substantial foundation, though private inholdings and access routes still require individual scouting.
What is the terrain like for a hunter on foot?
The unit is rolling, with some steeper breaks. Nearly 70 percent of the unit has gentle slopes, making much of the ground manageable for foot travel, though 30 percent of the terrain mixes moderate, steep and rugged slopes into that rolling base. Elevation spans from 8,000 to 12,900 feet, so hunters will encounter significant elevation change.
When should a hunter expect to find deer concentrated on winter ground?
Winter range and winter concentration together cover only 9 percent of the unit, meaning most mule deer are dispersed across the broader summer range through early fall. As November advances and snow falls—averaging 12.9 inches in that month—a hunter should expect animals to shift toward concentrated winter ground, though exact timing depends on weather and snow accumulation.
Does drawing an easy tag here mean a quiet hunt?
The unit draws at easy difficulty, often at zero points, but that reflects tag availability, not hunter traffic. GMU 171 experiences extreme hunter pressure despite its easy draw. An applicant with no preference points can draw the easiest unit-wide either-sex or buck code, but they will hunt in a heavily used unit.
Are the later rifle seasons in the rut, or do they come before it?
The primary rut runs November 11 to November 25. 3rd Rifle (November 7–15) spans the transition into and through the start of the primary rut, while 4th Rifle (November 18–22) occurs entirely within the primary rut. Earlier seasons—Archery, Muzzleloader, Early Rifle, 1st and 2nd Rifle—all fall before the rut begins.
How much ground can an applicant with zero preference points hunt?
An applicant with zero points can draw the easiest unit-wide either-sex or buck code and access all 52 percent of the generally open public land in the unit. State Trust Land hunting depends on which parcels CPW has enrolled in the Public Access Program, so that 3.5 percent is access-dependent and requires checking enrollment status.
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 — Deer 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
- CPW — Maps and GIS (Species Activity Mapping) — mule deer seasonal range
- CPW — State Trust Land Finder — which State Trust acreage is enrolled and open to public hunting
- Federal and state land-ownership datasets — land ownership and access
- NOAA climate normals — 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 August 31, 2026.