Unit 851

Mariquita Peak, Purgatoire Peak, and Francisco Peak provide primary glassing and orientation points across the high country. The Sangre de Cristo divide forms the western boundary and serves as a major terrain feature for navigation. Notable parks including Forty Acre Meadow, Wilkins Park, and Devils Park break the continuous forest and concentrate grazing wildlife.

Stonewall and Little Wall ridges offer useful terrain features for hunting strategy. Lost Lake, Strawberry Lake, and Duling Lakes mark reliable water sources in otherwise limited terrain. Rincon Creek, Quatro Creek, and Sierra Blanca Creek provide drainage navigation corridors.

The unit spans from mid-elevation foothills around 6,000 feet to alpine peaks above 13,000 feet, creating distinct habitat zones. Lower elevations support ponderosa and mixed conifer forests with scattered parks and meadows suitable for pronghorn and mule deer. Middle elevations transition through dense spruce-fir forests where elk concentrate during hunting season.

High ridges and plateaus above timberline offer open country for glassing and navigation. The elevation spread means significant seasonal migration patterns drive animal distribution.

The limited road network—roughly 175 miles of roads across moderate terrain—creates significant pressure concentration points. Most vehicle access clusters around valley bottoms and established settlement areas like Starkville, Stonewall, and Tijeras. Backcountry access requires foot travel or horse into the higher elevations, naturally filtering hunting pressure to motivated hunters.

The terrain's ruggedness, combined with access limitations, means early-season or rut-period competition concentrates in accessible parks and lower drainages. Higher elevation park areas see less pressure despite huntability.

Unit 851 occupies the border country of Costilla and Las Animas counties, bounded north by the West and North forks of the Purgatoire River and Colorado 12, east by I-25, south by New Mexico, and west by the Sangre de Cristo divide. This positioning places the unit in transition terrain between the southern Front Range and the San Isabel National Forest system. The geographic layout creates a natural hunt corridor with the state line to the south and major highway corridors defining other edges.

Water scarcity is a defining characteristic; reliable sources concentrate around the northern fork drainages and established lakes rather than distributing throughout the unit. Lost Lake, Strawberry Lake, and Duling Lakes provide consistent water in the high country. Lower drainages like Rincon Creek and Sierra Blanca Creek flow seasonally but support hunting activity in their valleys.

The Purgatoire River to the north provides reliable flow along the unit boundary. Hunters must plan movement around known water; waterless high ridges can quickly become limiting during dry periods.

Unit 851 supports healthy populations of elk across forested slopes, with migration patterns tied to elevation and snowfall. Early season finds elk in high parks and timberline zones; rut activity concentrates in accessible middle-elevation timber. Mule deer occupy mixed conifer slopes and transition zones; whitetails prefer dense riparian areas and lower canyons.

Pronghorn inhabit open parks and lower-elevation grasslands. Moose occur in willow drainages at higher elevations. Mountain lion and bear presence follows prey availability.

The rugged terrain and limited water access reward hunters who penetrate beyond roadside areas and focus on reliable water sources and high-country parks during midseason.