Unit 621

Key navigation references include Square Butte as a landmark visible across wide country, the Plunge as a known water point, and the ridge systems—Shetland Divide, Timber Ridge, Wilder Ridge—that serve as glassing lines and travel corridors. The Missouri River and Fort Peck Reservoir form the unit's backbone; Le Clair and Kepple Bottoms along the river provide access points and potential staging areas. CMR refuge roads (212, 201, 219) structure vehicle movement through the interior.

The islands scattered through the reservoir—Grand Island, Two Calf Islands—mark major water features but are relevant more for boundary context than hunting access.

This is low-elevation country between 2,200 and 5,700 feet, with most terrain falling below 3,000 feet—true high plains and breaks habitat. Sparse ponderosa pines cling to north-facing ridges and higher ground, particularly along features like Shetland Divide and Timber Ridge, but the dominant cover is open sagebrush, grassland, and shrub breaks. Scattered buttes—Green Mountain, Silver Peak, Shell Butte, and others—provide relief and thermal cover.

This isn't forested terrain; it's rolling plains interrupted by rocky ridges and deep coulees where water and shade concentrate wildlife during heat and drought.

Fair accessibility via 444 miles of county and CMR roads balances reasonable entry against the unit's size and isolation. Primary access corridors follow Highway 191 from the south and CMR roads from the west; most public hunters will stage from Zortman or Landusky and push into refuge roads. The vast, open nature and scattered water sources mean pressure concentrates around reliable springs and reservoir access; interior country away from main roads remains quiet.

Road density isn't extreme, so hunters willing to walk away from maintained routes find solitude. Cattle presence is significant; understand private property and CMR restrictions before planning.

Unit 621 occupies the transitional zone between the Missouri River's northern breaks and Fort Peck Reservoir's western arm in Blaine and Phillips Counties. The unit runs from Cow Creek's confluence with the Missouri northeast to Suction Creek, then follows the Fort Belknap Indian Reservation boundary southeast before returning west along Highway 191 and CMR roads. The boundary encompasses roughly 444 miles of roads weaving through isolated buttes, ranch country, and refuge lands.

Zortman and Landusky anchor the western flank; the unit extends eastward into increasingly remote breaks country toward the reservoir.

Water is the limiting factor here. Permanent water sources include Fort Peck Reservoir and the Missouri River, both eastern boundaries. Interior water relies on scattered springs—Mud Spring, Nantelle Spring—and seasonal creeks: Warm Springs Creek, Little Suction Creek, Rock Creek, and numerous coulees like Pugh, Ruby, and Chimney that run intermittently.

Several small reservoirs (Sorrell, Wrangler, Phillips, Rock Creek) exist but are isolated and may be private or restricted. Hunters must plan carefully around these limited, dispersed sources; springs and creeks dry seasonally, forcing understanding of current conditions before committing to a drainage.

Unit 621 holds elk, mule deer, white-tailed deer, and mountain lions across this broken terrain. Elk use ridge systems like Shetland Divide and ponderosa slopes for summer, then push to breaks and river bottoms during fire and fall; water-dependent in this dry country, they concentrate where springs and creeks run. Mule deer work the open flats and butte country; white-tailed deer favor riparian draws and creek bottoms.

Mountain lions follow deer through these same drainages and breaks. Glassing open ridges and hillsides is productive; follow water sources during dry periods. Early season focuses on higher terrain; rut hunting means checking coulees and creek bottoms where bucks work.

Late season shifts back to river bottoms and reservoir margins where game stays when snow closes higher elevations elsewhere.