The Wild Sheep Foundation is proud to present the Western Association of Fish and Wildlife Agencies, Wild Sheep Initiative 2025 Range-wide Status of Bighorn and Thinhorn Sheep in North America. This article features an introduction and a complete PDF to download.
The purpose is to provide a general overview of the current population status and general abundance trends for bighorn and thinhorn sheep throughout their range in North America. The Wild Sheep Initiative (WSI) consists of representatives from 20 state, territorial, and provincial agencies that comprise the Western Association of Fish and Wildlife Agencies (WAFWA).
The WSI’s mission is to provide a collaborative approach to finding solutions to improve wild sheep conservation and management. The general population status and trajectory of wild sheep populations is commonly requested by stakeholders including agency leadership, NGOs, hunters, and the public at large. To provide a quick snapshot of the status of these species, the WSI assembled this information by having each agency representative provide the current population status, and harvest information (Tables 1 – 3) and disease status/management for their respective jurisdiction. All states and provinces use very different methods to survey and estimate population size and harvest. Some jurisdictions do not estimate population size but rather look at changes in trend using different metrics including harvest, hunter effort, or trend counts. Wild sheep populations are below management goals in most jurisdictions, due to a variety of factors of which disease, primarily pneumonia, harsh winter conditions, and climate are perhaps the most important. Wildlife managers, veterinarians, and researchers have been tirelessly seeking solutions to population decline with some success.
Bighorn sheep (Rocky Mountain and California BHS – Table 1 and Desert BHS – Table 2) populations are generally stable with a recent downward trend across most jurisdictions (Figure 1), however, British Columbia is reporting significant declines in California BHS populations through the past 5 years.
Thinhorn sheep population status data is incomplete. In Alaska, managers estimate that Dall’s sheep have been stable with a recent dramatic, sharp decline due to extraordinarily harsh winter conditions. In British Columbia, Dall’s sheep have been stable, but estimates were increased in 2019 resulting from new genetic information that expanded the range of that subspecies to include areas previously identified as Stone’s sheep (Table 3, Figure 2). Stone’s sheep estimates from British Columbia show a similar trend over the past 23 years with a modest decline in 2020 (Table 3, Figure 2).
As sheep numbers decline, license availability and harvest follow suit. It is clear Dall’s sheep provides the majority of wild sheep hunting opportunity based on license issuance (on average >60%). On average, bighorn sheep, desert bighorn sheep and Stone’s sheep account for 35%, 5%, and 1% of wild sheep hunting licenses available, respectively (Figure 3). Interestingly, on average bighorn sheep and Dall’s sheep provide about an equal amount of harvest at 35% and 38%, respectively. And, on average, desert bighorn sheep and Stone’s sheep account for 16% and 11%, respectively (Figure 4).