California Big Horn Sheep Prescriptive
California Bighorn Sheep (Ovis canadensis californiana) are suited to rugged, mostly treeless terrain, to foraging sites with low-growing grasses to regions with shallow snow cover. They occur in the driest climate and on south to south-west oriented mountains. Bighorn sheep usually spend the winter on low-elevation bunchgrass ranges, ponderosa pine and douglas fir zones. They graze cured grasses such as fescue and bluebunch wheatgrass, which are key species on most winter range. A few herds of California Bighorn Sheep, among them a herd in the Chilko Lake/Nemiah Valley, spend the winter in windblown alpine ridges where they also spend the summer.
The Chilko Lake/Nemiah Valley are historical Bighorn Sheep habitat and once the entire range was inhabited by sheep. Presently the Bighorn Sheep population is displaced from the North half of the range. Due to increased human access by logging roads (motorcycles, ATV, above 1500m), sheep are increasingly disturbed in their natural habitat by outdoor recreation vehicles (ORV). Bighorn Sheep are sensitive to noise-induced stress and are displaced from the North end of the Chilko Lake/Nemiah Valley mountain range.
California big horn sheep are currently on the Blue List of terrestrial vertebrates and classified as vulnerable. Previous studies have shown that human activity and increased stress results in displacement of sheep herds, smaller populations sizes and decreased survival rates.
Issues:
- Increased human activity in the high elevations of the Chilko Lake/Nemiah Valley mountains, resulting in displacement of the local sheep population
- Increased use of motorbikes in the alpine areas destroying habitat and sound quality for sheep population
Goals:
- Protect the Chilko Lake/Nemiah Valley Bighorn sheep population and their habitat
- Collaborate with local institutions including the BC Wildlife Federation, First Nations, loggers, outfitters and local administration to enforce regulations and limitation for the recreational use of the Chilko Lake/Nemiah Valley mountains above 1,500 meters elevation.
- Attachment of road signs to make riders aware of the effects and risks to the big horn sheep population.
- Continued long-term monitoring and management of the site by increased policing to ensure for constant habitat quality and eliminated displacement.