GMU 137 GMU 137 — Las Animas/Baca Co.
Grassland pronghorn and canyon-rim mule deer where the plains meet the mesas
Southeast Colorado plains — Mesa de Maya country and Comanche grassland · Last reviewed 2026-07-12
Area
578
sq mi
Public land
22%
approx.
Elevation
4,500–6,200
feet
Motorized
moderate
access
Overview
GMU 137 lies in far southeastern Colorado where Las Animas and Baca counties meet, a shortgrass and sandsage tableland incised by the Purgatoire drainage and rising toward the juniper-capped mesas of the Mesa de Maya and Black Mesa country. It carries a meaningful share of the Comanche National Grassland, giving it better public access than the plains average. Pronghorn are the marquee tag on the open flats, mule deer hold the canyon rims and mesa breaks, and elk — while a small herd — show the best success of the three neighboring units in this rougher canyon-and-mesa terrain. Whitetails cling to the river bottoms. Ranch private still covers most of the map.
Terrain
Shortgrass and sandsage tableland cut by the Purgatoire and its arroyos and broken by rimrock canyons and the higher juniper-capped mesas of the Mesa de Maya/Black Mesa uplift.
Cover: Shortgrass prairie, sandsage, cholla, and yucca on the flats; juniper/pinon, scrub oak, and cottonwood/brush riparian on the mesa breaks and canyon bottoms.
Landmarks: Mesa de Maya / Black Mesa uplift · Purgatoire River drainage · Comanche National Grassland · Kim · Branson
Access
GMU 137 holds significant Comanche National Grassland acreage, and CPW has weighted its tags toward private-land-only to spread hunters across that public ground — so the accessible blocks see pressure. Grassland ownership is checkerboarded with private ranches; read boundaries carefully around the mesas and canyons. Colorado State Trust Lands are NOT huntable unless enrolled in CPW's Public Access Program. Off the Grassland you need permission, a lease, or a Walk-In parcel.
Managers: USFS Comanche National Grassland, private ranch, Colorado State Trust Land (access-restricted), CPW State Wildlife Areas / Walk-In Access
Access points: Comanche NG access roads south of US 160/toward Branson and Kim · County road grid off the highways · Mesa and canyon two-tracks (high-clearance) · CPW Walk-In Access properties (annual atlas)
Species notes
Pronghorn
common opportunityThe marquee tag, part of CPW's Tobe (PH-13) pronghorn herd. Antelope hold the open shortgrass and fallow ground between the mesas and canyons; tags are limited-draw with moderate success. Access and locating the right ground drive the hunt.
- →Glass open shortgrass flats and benches below the mesas
- →Use terrain rolls and arroyos to stalk within range
- →Ambush water and crossings in early-season heat
- →Hunt confirmed Grassland sections and secured private
Mule Deer
common qualityA quality plains-and-mesa mule deer unit — bucks use sandsage draws, cholla flats, and the juniper mesa rims and canyon breaks. Fully limited-draw; the rougher terrain can hold a genuinely mature buck with the right access.
- →Glass mesa rims and rimrock at first and last light
- →Still-hunt juniper breaks and side canyons
- →Watch travel between mesa bedding and grassland or field feed
Rocky Mountain Elk
limited opportunityA small canyon-and-mesa elk herd that punches above the neighboring units on success — this rougher, more broken country holds elk better than the open plains, though harvest is still low. Tags are limited-draw; this is not over-the-counter mountain elk.
- →Glass the roughest mesa breaks and canyon rimrock
- →Hunt sign in the least-disturbed public and private-adjacent ground
- →Be ready to pack out of steep, waterless canyon country
Whitetail Deer
limited qualityA limited whitetail component holds the brushy river and creek bottoms, overlapping mule deer at the edges. A localized but genuine river-bottom opportunity.
- →Hunt cottonwood and brush corridors along the drainages
- →Set up on cover-to-feed travel
- →Focus the rut in the tightest bottom cover
Pro tips
- →GMU 137 holds real Comanche Grassland — pull the ownership map and hunt the confirmed public mesa-and-flats blocks
- →The rougher mesa/canyon country is the elk edge here — hunt the breaks, not the open plains, for elk
- →Split effort: pronghorn on the flats, mule deer on the mesa rims, whitetails in the bottoms
- →Do not plan on State Trust sections unless they're enrolled in the Public Access Program
- →Carry high-clearance and recovery gear; canyon two-tracks are unforgiving when wet
Watch out for
- !Checkerboarded Grassland and private ranch sections — verify the public boundary before you hunt
- !State Trust Lands are closed to hunting unless enrolled in CPW's Public Access Program
- !Mesa and canyon roads become impassable clay when wet
- !Limited water and early-season heat in steep canyon country
- !Pressure concentrates on the accessible Grassland blocks
Logistics
Kim and Branson are tiny service points; Trinidad to the west and Springfield to the east are the real supply towns for fuel, lodging, and groceries. Roads are a county grid; mesa and canyon two-tracks want high-clearance and turn greasy when wet. Cell coverage is spotty away from the highway and gone in the canyons — carry a map and backup navigation.
Nearest towns: Kim, Branson, Trinidad, Springfield
Seasons & regulations
This page carries no season dates or regulations. Get current rules from the official Colorado sources:
Research sources: CPW Pronghorn Management Plan DAU PH-13 (Tobe) — GMUs 130,136,137,138,143,144,146 · CPW Southeast Colorado Big Game Brochure (2018) · Comanche National Grassland — USFS Pike-San Isabel
FAQ
- How big is GMU 137 in Colorado?
- GMU 137 (GMU 137 — Las Animas/Baca Co.) covers about 578 square miles, ranging from roughly 4,500 to 6,200 feet in elevation. Area is computed from the unit boundary polygon.
- How much public land is in GMU 137?
- Approximately 22% of the unit is public land. Primary managers: USFS Comanche National Grassland, private ranch, Colorado State Trust Land (access-restricted), CPW State Wildlife Areas / Walk-In Access. Always verify ownership boundaries on the ground.
- What species does the catalog list for GMU 137?
- Pronghorn, Mule Deer, Rocky Mountain Elk, Whitetail Deer. For seasons, tags, and regulations, use the official Colorado agency resources linked on this page — this page carries no regulatory information.
Put GMU 137 on your map.
Boundary lines, public/private ownership, topo, and offline maps for this unit — in Baseline Maps, free for 14 days.