Unit 146, Colorado

Flat to gently rolling short-grass prairie dominates the northern two-thirds of the unit, interrupted by the Arkansas River floodplain along the northern boundary. The southern portion breaks into shallow canyons and broad mesas. Elevation ranges from 3,622 feet in the eastern lowlands to approximately 4,600 feet at the southern uplands. The terrain is among the most physically accessible (low slope) of any Colorado big-game unit; the limiting factor is private land, not terrain difficulty.

The unit is bounded by U.S. Highway 50 on the northwest, U.S. Highway 287 on the east, the Prowers-Baca and Bent-Baca county lines on the south, and Colorado Route 101 plus improved Pritchett–Las Animas roads on the west. These highways (US 50, US 287, CO 101) are the primary access corridors to the county road network. Public hunting land is extremely limited at approximately 4–8% of the unit area (HuntScore: ~4% federal/public + ~4% state land; unit is ~96% private per HuntScore overview); essentially all productive habitat is on private ranch land requiring landowner permission. Two confirmed public parcels: (1) Keller Lease State Land (~1,520 acres), reached from CO 101 three miles south of Las Animas via County Road DD east, then County Road 13 to CR EE, then north on CR 13.5 connecting to CR FF.5 — offers deer and pronghorn hunting; (2) John Martin Reservoir area (~19,471 acres shared with adjacent units 125 and 126), located off County Road 24 east of Las Animas on US 50. IMPORTANT ACCESS NOTE: Effective September 1, 2023, the U.S. Army Corps of Engineers assumed management of this area from CPW. Hunting and fishing remain permitted with standard CPW hunting/fishing licenses; however, the prior requirement for all visitors to hold a CPW license regardless of activity no longer applies under federal management. Dispersed camping at dozens of undeveloped campsites and off-road travel beyond main roads are no longer permitted. NOTE: HuntScore describes hunting as not permitted at John Martin; hunters should verify current Army Corps rules before hunting this parcel. No National Forest or BLM land falls within the unit boundaries. No designated Wilderness areas exist here. No seasonal big-game road closures apply (plains unit, no forest roads).

Shortgrass prairie (blue grama, buffalo grass) is the matrix cover type across the uplands. Sand sage and sagebrush occur in scattered patches. Riparian corridors along the Arkansas River and its side drainages — Rule Creek, Mud Creek, Dry Creek, and Caddoa Creek — support cottonwood, willow, Russian olive, and Russian thistle. Yucca and prickly pear cactus are common on the drier mesa and canyon slopes in the south. Conservation Reserve Program (CRP) fields provide additional grass cover in the agricultural zones. Center-pivot and dryland cropland are scattered throughout.

White-tailed deer are the signature big-game species; the Arkansas River riparian corridor is nationally regarded for trophy-class whitetails that concentrate in cottonwood-willow draws adjacent to cropland. Mule deer occupy the shortgrass uplands and are widespread across the unit; both species use the river bottoms and side drainages. Pronghorn are distributed across the open prairie throughout the unit but virtually all habitat is on private land, with very few animals accessible from public ground. Turkey are present in limited numbers in agricultural zones near the river. Black bear and mountain lion are listed as huntable species in GMU 146 by CPW, though both are uncommon on the eastern plains; any activity likely follows riparian draws. No established elk herd exists in the unit — GMU 146 has no elk DAU designation and does not appear in CPW elk license tables. Deer populations in DAU D-035 are estimated at 6,820–7,490 animals with a population objective of 7,000 (within management range as of 2025).