Excerpt from BCWF 2024 Annual Repot (shared at the 2025 AGM)
The Sheep Shape project aims to investigate how seasonal range conditions influence the body condition of Stone's sheep in the Finlay-Russell, Talatui, and Swannel ranges. These regions represent the southernmost edge of their range in central British Columbia, where the population appears to have undergone an apparent 50-percent decline since 1993. Stone's sheep, a species found almost entirely in B.C., play a critical role in the province's biodiversity, making the health of these habitats vital for the conservation of this unique species.
Traditionally, management efforts have focused on improving winter range habitats in response to animals observed in poor condition during winter. However, recent insights suggest that the quality of summer range habitat may have a more significant impact on the energy reserves that sheep carry into winter. Enhanced summer ranges could allow sheep to accumulate greater fat reserves, providing a buffer against the harsh conditions of winter. In contrast, improved winter habitats may become inaccessible due to snow and ice accumulation, particularly with the increasing frequency of icing events driven by climate change. This makes reliance on winter range improvements a riskier strategy.
To investigate this, body fat measurements will be taken twice a year from 20 GPS-collared Stone's sheep: first, in late fall, when animals are at peak body condition, and second, in late winter, after they have depleted their energetic reserves. Body condition will be assessed using an ultrasound to estimate rump fat thickness, providing a reliable measure of fat reserves. These measurements will be paired with forage quality samples collected from the seasonal ranges of each collared sheep. This approach allows for a detailed analysis of how forage availability and quality impact body condition.
Given the critical role fat reserves play in survival and reproduction, maximizing these reserves is essential for the conservation of Stone's sheep, especially in light of their decline. This underscores the need for effective, targeted conservation efforts to safeguard their future.
The additional benefits of diverse topography and varying snow accumulation within the study area lead to distinct summer and winter range conditions. This natural variation provides an opportunity to test the hypothesis that higher-quality seasonal ranges can significantly enhance body condition during the respective seasons. By combining body fat measurements with forage quality data, the study aims to provide critical insights into the role of habitat quality in the overall health and survival of Stone's sheep. Ultimately, the goal is to develop a more sustainable and effective conservation strategy, addressing both current needs and future challenges posed by a changing climate.
Respectfully submitted by Landon Birch
