West Desert, Rush Valley, Utah

Rush Valley itself is a 30-mile-long north-trending valley in southeastern Tooele County, roughly 4,200-5,800 feet in elevation on the valley floor. The unit is bounded on the east by the Oquirrh Mountains (Flat Top Mountain, 10,620 ft, is the range high point; Lowe Peak is a prominent visible landmark from Salt Lake City) and on the west by the Stansbury Mountains (Deseret Peak, 11,035 ft, is the range high point) and the Onaqui Mountains (Stookey Benchmark, 9,019 ft). The southern portion is bounded by the Sheeprock Mountains (Dutch Peak, 8,964 ft). The valley narrows to about 7 miles wide in the north between the Stansbury and Oquirrh ranges, then widens southward to approximately 15 miles. Rush Lake, a shallow marsh in the north of the valley, is fed by snowmelt draining from surrounding ranges. The terrain is classic Great Basin basin-and-range, with flat to gently rolling valley floors, alluvial fans, and rugged mountain ridgelines. Pronghorn occupy the valley floor and lower foothills; the higher mountain terrain is not pronghorn habitat.

The unit is approximately 43% public land (25% BLM, 12% Utah state trust lands, 6% USFS, 1% designated wilderness) and 57% private, making access planning critical. Primary access routes are Utah SR-36 (running north-south through the center of Rush Valley from Tooele/Stockton toward Eureka) and Utah SR-73 (entering from Lehi to the east, joining SR-36 at the valley center). Utah SR-199 enters from Dugway in the west. BLM roads provide good dispersed access across much of the public land in the valley and lower foothills. Two separate sections of Tooele Army Depot lie within the unit boundary and both are closed to public access and hunting. The boundary explicitly excludes all CWMUs and all Native American trust lands within the boundary perimeter.

Valley floors and lower foothills are dominated by big sagebrush (Artemisia tridentata), rabbitbrush, and desert grassland. Native bunchgrasses, forbs, and shrubs provide essential forage. Mid-elevation foothills transition to pinyon-juniper woodland on the flanks of the Onaqui, Stansbury, and Sheeprock ranges. Riparian corridors are limited but present near Rush Lake and seasonal drainages. Invasive cheatgrass (Bromus tectorum) is a fire-risk concern throughout the unit, and encroachment of pinyon pine and juniper into shrublands has reduced forb and shrub availability in some areas. Domestic sheep grazing is prevalent across the unit and represents a management concern for pronghorn forage competition.

Pronghorn antelope are the primary big game species actively managed under this specific boundary. Spring trend counts recorded 481 animals in 2019 (111 bucks, 370 does and fawns) and 221 animals in 2021 (53 bucks, 168 does/fawns); no survey data were recorded 2022-2024, leaving current herd size uncertain. Buck-to-doe ratios 2015-2024: 56, 45, 76, 18, 34, 59, 39, 30, 33, 35. Fawn-to-doe ratios 2015-2024: 60, 66, 50, 39, 53, 33, 25, 50, 48, 53. Average age of harvested bucks: 4.1 (2022), 3.5 (2023), 3.2 (2024), above the 2.0-3.0 year management objective, indicating a mature buck cohort. The BLM Onaqui Herd Management Area (approximately 205,000 acres) hosts approximately 450 feral horses that can compete with pronghorn at water sources.

Stansbury peak corrected: draft Vickory Mountain 10,305 ft is unsupported; verified high point Deseret Peak 11,035 ft. Oquirrh peak corrected: draft said Lowe Peak is the high point; actual high point is Flat Top Mountain 10,620 ft. 2017 population ~300 deleted: no survey data for 2017 in UDWR annual report (only 2019=481 and 2021=221 recorded).