The history of bighorn sheep (Ovis canadensis) conservation shares many similarities with the conservation history of other North American ungulates, but is also quite distinctive.
Similar to other ungulates, bighorn sheep existed in continuous and broadly distributed populations and likely numbered in the millions prior to colonization of western North America. Following settlement of western North America by Euro-Americans, bighorn sheep and other ungulate species experienced drastic reductions in numbers and extirpation from much of their former range, which prompted a dedicated restoration effort by wildlife management agencies throughout the 20th century. This effort was successful in recovering most ungulate species back from perilously low populations.
Restoration efforts of most ungulates entailed regulating harvest, protecting habitat, and translocating animals to facilitate colonization of previously occupied habitat — a prescription that has been successful to the point that wildlife managers are now challenged by conflicts between broadly distributed and abundant wildlife populations and humans. However, such issues are rarely described as challenges for bighorn sheep management.
There are currently estimated to be approximately 80,000 wild bighorn sheep in North America, representing a fourfold increase compared to the beginning of restoration efforts, but still likely at least a tenfold decrease from historic numbers.
Montana plays an important role in bighorn sheep conservation in a variety of ways. One noteworthy way are the world-class genetics on an island on Flathead Lake. Three of the top five Rocky Mountain bighorn sheep recorded by the Boone and Crockett Club have come from Wild Horse Island on Flathead Lake. Found between 2015 and 2018, these three winter-killed, pick-up heads were officially scored, entered, and accepted by B&C at 205-2/8, 209, and 216-3/8, a new world record.
Montana's draft Bighorn Sheep Conservation Strategy, which sets the overall direction of bighorn sheep management in Montana for the next 10 years, draws together in one document the history of the state's Rocky Mountain bighorn sheep from decline to recovery.
It also offers key narrative histories of all existing herds, including past and current management and the opportunities and challenges facing each population. Each narrative fully describes the factors in play when FWP considers hunting-license and harvest-quota levels.
For wildlife managers, the strategy outlines how FWP will monitor herd health and the status and condition of bighorn sheep habitat. It provides guidelines for trapping and transplanting bighorns and a process to help identify areas that might be suitable for transplanting bighorn sheep now and into the future.
The strategy establishes eight statewide objectives, yet seeks to remain flexible enough to incorporate new ideas and technological and scientific advances. Most important, it allows managers to adapt to changes in bighorn populations and their habitats as they occur.
While Montana has never before produced a comprehensive plan for bighorn sheep management, it has a 60-year history of successfully reestablishing bighorn populations across the state. That success has helped Montana to acquire an international reputation for managing robust bighorn sheep populations.
There are now 45 populations of bighorns across Montana with 36 sustaining limited hunting. Officials estimate that 5,700 bighorn sheep inhabit Montana, excluding Yellowstone and Glacier national parks.
The new strategy tackles a number of wildlife management concerns, including:
occasional large-scale die-offs often associated with contact with domestic sheep or goats
systematic long-term health monitoring
genetic integrity of native populations
establishing bighorn sheep populations to new areas
loss of habitat and development impacts to some bighorn populations
hunting and other recreational opportunities
To view annual harvest reports and more information, click here.
Montana offers hunting opportunities for bighorn sheep.
January 2017 — A new wildlife health monitoring program hopes to prevent bighorn sheep disease outbreaks.
Highland Bighorn Sheep Project
Correlates of Recruitment in Montana Bighorn Sheep Populations
Proactive Management of Pneumonia Epizootics in Bighorn Sheep in Montana
Proactive Decisions (PDF)
The role of disease, habitat, individual condition, and herd attributes in bighorn sheep recruitment and population dynamics in Montana
The Shiny application can be found here
Evaluating sample size to estimate genetic management metrics in the genomics era (PDF)
Is habitat constraining bighorn restoration? a case study (PDF)
Restoration potential of bighorn sheep in a prairie region (PDF)
Behavior-specific habitat models as a tool to inform ungulate restoration (PDF)
Evaluating wildlife translocations using using genomics: A bighorn sheep case study (PDF)
Regional variability in Rocky Mountain bighorn sheep pregnancy and survival rates (PDF)
Drivers of variation in the population dynamics of bighorn sheep (PDF)
New Book: Greater Yellowstone's Mountain Ungulates
In early 2021, staff from Montana Fish, Wildlife & Parks and partnering organizations recently released 26 bighorn sheep into the Tendoy Mountains as part of a new effort to re-establish a wild sheep herd there.
The sheep — 19 ewes, five rams and two lambs — were captured from Wild Horse Island on Flathead Lake, where sheep numbers have grown past management objectives. Each of the sheep had healthy body conditions when they were successfully released.
