Colorado GMU 581 Mule Deer Hunting
Park, Teller and Fremont counties, central Colorado · 689 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 581 is like
Unit 581 spans 689 square miles across Park, Teller and Fremont counties in Colorado's central region. Elevation ranges from 5,300 feet to 10,900 feet, with a typical elevation around 8,500 feet. The terrain is rolling to moderately steep, with 47 percent gentle slope, 40 percent moderate slope, 13 percent steep slope, and 1 percent rugged ground by area. The unit offers a mix of high country and foothill habitat suitable for mule deer hunting across multiple seasons and weapon types.
Public hunting ground comprises roughly 36 percent of the unit (245 square miles) on BLM, National Forest and State Wildlife Areas. Colorado State Trust Land makes up an additional 4.1 percent (28 square miles), though access there depends on enrollment in CPW's Public Access Program. National Park Service land covers 1.4 percent and is closed to hunting. Ownership of roughly 2.9 percent is unclassified, and private land accounts for 56 percent of the unit. The public ground available to hunters is fragmented across federal and state agencies rather than consolidated, which affects routing and planning.
Mule deer occupy the unit across extensive seasonal ranges. Summer Range covers 93 percent of the unit, while Winter Range covers 91 percent, indicating that seasonal movement occurs but across broad swaths rather than through narrow corridors. Winter Concentration comprises 28 percent of the unit, marking areas where mule deer cluster as the season progresses. As conditions cool through fall and snow accumulates, hunters should expect deer to shift toward concentrated areas, though timing and extent vary with weather and snow.
The unit offers five seasons: Archery from September 2–30 (either-sex), Muzzleloader September 12–20 (doe or buck), 2nd Rifle October 24–November 1 (doe or buck), 3rd Rifle November 7–15 (doe or buck), and Late Rifle September 1–October 31 (doe only). Three rifle seasons are available. Archery and Muzzleloader fall during velvet shed and early fall transition when bucks are shedding velvet and beginning nocturnal movement. 2nd Rifle spans early fall migration and early pre-rut stages. 3rd Rifle covers early pre-rut and primary rut periods. Late Rifle runs through velvet shed, early fall migration, and early pre-rut phases. Weather cools significantly across the fall, with September highs around 68°F dropping to November highs near 45°F, and snowfall increases from 0.1 inches in September to 3.1 inches in November. Draw difficulty for the easiest unit-wide buck or either-sex code for adult Colorado residents is moderate, requiring 1–2 preference points.
Terrain & elevation
- Elevation
- 5,300–10,900 ft, typically around 8,500 ft
- Steepness
- Steep — mean slope 13.2°
- Slope breakdown
- 47% gentle · 40% moderate · 13% steep · 1% rugged
- Ground you can count on
- ~245 sq mi, plus ~28 sq mi of State Trust Land where access depends on enrollment
Land & access
About 36% of GMU 581 is public land a hunter can count on — BLM, National Forest and State Wildlife Areas. A further 4% is State Trust Land, which is huntable only where CPW has enrolled it. Another 1% is public but closed to hunting — National Park Service.
- BLM23%
- National Forest12%
- State Wildlife Area2%
- State Trust Land4%
- National Park Service1%
- Unclassified ownership3%
- Private56%
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 581 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%.
- 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
- Summer Range93%used in summer
- Winter Range91%used in winter
- Winter Concentration28%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 |
| 2nd Rifle | October 24 – November 1 | Doe, Buck |
| 3rd Rifle | November 7 – November 15 | Doe, Buck |
| Late Rifle | September 1 – October 31 | Doe |
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 68°F, lows around 36°F, about 0.1 in of snow (mid-elevation normals)
- October — highs around 57°F, lows around 25°F, about 2.1 in of snow (mid-elevation normals)
- November — highs around 45°F, lows around 15°F, about 3.1 in of snow (mid-elevation normals)
GMU 581 mule deer hunting FAQ
How much of this unit can a hunter realistically access on public land?
About 36 percent of the unit is generally open to public hunting on BLM, National Forest and State Wildlife Areas. An additional 4.1 percent is Colorado State Trust Land, but only parcels enrolled in CPW's Public Access Program are huntable—enrollment varies. The remaining 56 percent is private land, and 2.9 percent is unclassified. Hunters should plan access before applying.
Is this unit realistic for a hunter with zero or very few preference points?
Yes. The easiest unit-wide buck or either-sex code for an adult Colorado resident in the primary draw requires 1–2 preference points and has drawn reliably at that tier. This applies only to the specific easiest qualifying hunt; other seasons, codes and nonresident applicants may require substantially more points.
Which seasons are best for hunting the rut?
The 3rd Rifle season (November 7–15) covers early pre-rut and primary rut phases when bucks are most active and responsive. 2nd Rifle (October 24–November 1) begins as migration and early pre-rut behavior intensifies but misses the peak rut window.
Does this unit's terrain require extreme fitness or technical skills?
No. The unit is rolling to moderately steep, with only 1 percent rugged ground. About 47 percent is gentle and 40 percent is moderate slope, making much of it accessible to hunters of varying ability. Steeper pockets exist but do not dominate.
When should hunters expect the most significant weather changes?
October and November see the sharpest shifts. October averages 2.1 inches of snowfall and highs around 57°F; November jumps to 3.1 inches of snowfall and highs near 45°F. Hunters planning late-season hunts should prepare for cold temperatures and accumulating snow.
Is there a large early-season window before the rut begins?
Yes. Archery (September 2–30) and Muzzleloader (September 12–20) both occur during velvet shed and early fall transition, well before the primary rut begins in mid-November. Early-season hunters can pursue deer before the most dramatic behavioral shifts occur.
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.