Sweetwater Rocks Bighorn Sheep Reintroduction Fact Sheet 3/8/2022
• The Current proposal to assess a Sweetwater Rocks bighorn sheep reintroduction was proposed by a local landowner (Pathfinder Ranches) to the Wyoming Game and Fish Commission (WGFC) in July 2021.
• The Wyoming Wild Sheep Foundation (WY-WSF) is committed to working cooperatively through the
Wyoming Statewide Bighorn/Domestic Sheep Interaction Working Group Final Recommendations (the Wyoming Plan) to re-establish bighorn sheep to their native range while also supporting Wyoming’s agricultural heritage.
• Creating State-specific federal policy has the potential to be extremely beneficial to livestock
producers in wildlife management decisions into the future.
Most current information for people to see
Historically, Wyoming supported widespread populations of bighorn sheep across the state (Boness and Frost 1942, Buechner 1960). Early taxonomic studies classified these bighorns as either “Audubon’s” bighorn sheep or “Rocky Mountain” bighorn sheep (Cowan 1940). Audubon’s sheep inhabited mountain ranges, badlands, and rimrock breaks across eastern Wyoming, eastern Montana, and the badlands of North and South Dakota and Nebraska. These animals tended to be non-migratory, obtaining all habitat components within restricted yearlong ranges. Rocky Mountain sheep, in contrast, occurred within Wyoming’s western mountains and exhibited strong migratory behavior. This subspecies wintered in low elevation foothills habitats and summered in alpine habitats above 10,000 feet.
Bighorn sheep were native to the Sweetwater Rocks and surrounding mountain ranges. As early as 1812, Robert Stuart reported sheep from central Wyoming (Boness and Frost 1942). Traveling along the route that eventually became the Oregon Trail, Stuart described “numerous flocks of ibex or bighorn” along the Platte River. He noted that mountainous country to the south, southwest, and east of Poison Spider Creek were occupied by “innumerable flocks” of wild sheep. John C. Fremont harvested bighorn sheep in the vicinity of Devil’s Gate during his expedition of 1842 (Fremont 1887). In 1878, a diary account by Edwin C. Johnson reported that bighorns were common in Platte Canyon, the Sweetwater Rocks, and Brown’s Canyon (Beebe 1973). Similarly, a Mr. J. B. Gaynor of Thermopolis reported harvesting a bighorn ram near Savage Peak north of the Sun Ranch in 1881 (Anonymous 1931)
It is believed the Audubon subspecies inhabited the Sweetwater Rocks (Cowan 1940, Buechner 1960, Shackleton 1985). Following settlement of the lower Sweetwater River, market hunting, introduction of exotic diseases from domestic livestock, and forage competition with domestic livestock, these extant animals were extirpated around 1907 (Cowan 1940, Boness and Frost 1942). Similarly, Audubon’s sheep became extinct across their entire range in the early 1900s. One of the last accounts of this subspecies was described by Theodore Roosevelt in the Bighorn Mountains (Morris 1979). Rocky Mountain bighorns have persisted in Wyoming to the present, although the subspecies’ distribution was greatly restricted and many individual populations were dramatically reduced as human settlement and the introduction of domestic sheep reached a peak in the early 1920s (Boness and Frost 1942, Smith 1982, Ryder and Lanka 1997).
Beginning in the 1940s, the Department began transplanting Rocky Mountain sheep into formerly occupied bighorn habitats. Through the years, approximately 2,000 bighorns from Whiskey Mountain near Dubois were released into the Wind River Mountains, the Wyoming Range, the Bighorn Mountains, the Black Hills, the Laramie Mountains, the Snowy Range, the Sierra Madre Mountains, and 5 other western states (Hurley 1996). In most instances, transplants of these Rocky Mountain bighorns into former Audubon sheep habitats failed or were only marginally successful (Cook et al. 1990, Hengel et al. 1992, Easterly 1996, Hiatt 1997).
Department perso1mel attempted to re-establish bighorns in the Savage Peak area of the Sweetwater Rocks tlu·ough 3 transplanting operations (Wyoming Game and Fish Department 1950, Hiatt 1997). In 1944, 7 desert bighorn sheep (0. c. nelsoni) from southern Nevada were released just south of Savage Peak. This is the only documented account of desert sheep being released into Wyoming. In 1949 and 1950, an additional 20 Rocky Mountain sheep from Whiskey Basin were transplanted into the same area. Despite the extremely small founder herd, the population increased to a maximum of 40-50 animals during the 1960s. Following this initial increase, however, the population dwindled through the 1970s. By 1980, reports of resident bighorn sheep in the Sweetwater Rocks ceased. However, occasional sightings of wandering animals were made by area residents though the 1990s.
A second attempt to re-establish bighorns in the Sweetwater Rocks was proposed in the mid 1980s. The proposal was presented to the public during development of the BLM’s Lander Resource Management Plan. Following signing of the Plan in 1987, the BLM stated, “BLM will cooperate with the Wyoming Game and Fish Department, interested sportsmen, conservation groups, and adjacent landowners in efforts to develop a workable bighorn sheep re-introduction program for the Sweetwater Rocks area.” However, strong landowner opposition to a transplant of bighorns at that time and changing Department management objectives for elk caused the proposal to be abandoned.
Step into our resource Vault to use our library of documents pertaining to the reintroduction of BHS into Sweetwater Rocks
Links to our