La Sal, Dolores Triangle, Utah

Classic Colorado Plateau terrain: east-to-west draining canyon systems cut into red-rock mesas and plateaus, with the canyon floors near the Colorado and Dolores rivers at the unit's lowest points. Elevation spans approximately 4,318 to 7,682 feet, though the vast majority of winter wildlife use concentrates between roughly 5,000 and 6,000 feet on the lower mesas and canyon benches. Terrain is rugged with steep canyon walls, broad grassy flats on mesa tops, and river corridor bottomlands. A portion of the unit is classified roadless and requires a river crossing to access.

Land ownership (per 2025 UDWR Unit 13B Deer Plan): BLM 91.7% (~92,482 acres), Utah State Institutional Trust Lands 5.19% (~5,236 acres), private 2.65% (~2,675 acres), UDNR 0.46%. No National Forest land. The BLM Moab Field Office (82 E Dogwood Ave, Moab, UT 84532; 435-259-2100) administers the majority of the unit. Primary vehicle access is via Colorado on several four-wheel-drive roads from the Gateway/Glade Park area; from the Utah side, the Onion Creek Road (off UT-128) provides 4WD access through numerous wash crossings into the canyon system. The Castleton-Gateway gravel road and the Dolores River corridor road from Gateway, CO to the mouth of Beaver Creek are noted routes. A designated roadless area exists in a portion of the unit; accessing it requires a river crossing. The BLM is in the process of finalizing a Travel Management Plan for the ~130,000-acre Dolores River Travel Management Area that includes this unit. Private land in the unit is minimal (~2.65%) and not organized as a CWMU. Hunters should carry spare tires and extra supplies — some areas are hours from the nearest town.

Lower elevations (4,300–5,500 ft) are dominated by blackbrush scrub and desert shrub communities, transitioning to pinyon-juniper woodland across the broad mid-elevation mesas (5,500–7,000 ft). Riparian corridors of cottonwood and willow line the Colorado and Dolores river margins. Sagebrush steppe communities occupy some benches and are noted as critical winter forage; encroachment by pinyon-juniper into sagebrush habitats is an ongoing management concern. Cheatgrass invasion is documented on lower winter range sites. The unit has no forest service lands and no high-elevation aspen or spruce-fir zones — it functions entirely as winter range for deer and elk that spend other seasons in Colorado's higher terrain.

Mule deer are the primary game species; the unit is designated entirely as winter range for deer that summer in Colorado's Unit 40. Population target is 3,000 wintering deer; the 2024 modeled estimate was approximately 1,577 animals, well below objective. About 40% of Colorado Unit 40's deer herd winters in Utah. The unit is managed under a limited-entry strategy for 25–30 bucks per 100 does. Elk also use the unit exclusively as winter range, with 300–700 elk typically present depending on snowfall severity at their Colorado summer range; a 2021 aerial survey counted 400 elk. Elk spend spring, summer, and fall in Colorado's Glade Park and Pinon Mesa area (Unit 40) and migrate into Utah during December and January. Black bears are present and the Dolores Triangle was established as its own bear hunting unit beginning in 2026 (separated from the La Sal bear unit). Mountain lions inhabit the unit year-round. Peregrine falcons, bald eagles, and golden eagles have been documented. The Colorado and Dolores river corridors provide riparian habitat supporting songbirds and other non-game wildlife. CWD has been documented in the neighboring La Sal Mountains unit (Unit 13A) at the highest prevalence rates in the state (approximately 20–25%); the Dolores Triangle (13B) is monitored for CWD but CWD-positive status has not been explicitly confirmed in available sources for this subunit specifically.