Rocky Mountain Bighorn Sheep Habitat Enhancement Plan

Introduction

This project aims to develop enhancement plans for various areas in order to continue habitat enhancement activities. To create such plans, areas on bighorn sheep winter range that are suitable for potential habitat enhancement must be identified, the types of enhancements have to be determined and the different areas should be prioritized.

Background

The Rocky Mountain bighorn sheep population numbers have had a decline of 200 animals form 1991 to 2006 in the Premier Ridge, Estella and Wildhorse herds. This is due to loss of open range especially for spring, fall and winter habitats which is a result of forest encroachment. The Ministry of Forest has been suppressing fires in the East Kootenay Trench Ecosection and the adjacent Montane spruce biogeoclimactic zone for 60 years. The result is a buildup of forest, loss of bunch grass and reduction of sight lines which makes the sheep vulnerable to predators.

Areas of Interest

Overall, the areas of interest to the enhancement project are the Wildhorse area especially places like Lone Peak, Brewery Ridge and the Lower Lakit Mountain, the Estella area with its mountains, the Lewis Creek badlands, Herbert Creek and lastly the Premier Ridge Area.

Methods

The site selection was based on many different criteria. For example the historical and present distribution of the bighorn sheep, distance to escape terrain, seasonal range and movement corridors, risk to other values like rare and endangered species, archeological values and grazing rights were all site selection criteria.

Treatment Unit Priorities and Recommended Treatments

Initially two sites were chosen for stand management; the Lower Wasa Mountain and Herbert Face. They both showed resident and transplanted sheep and under-story grass and shrubs. With enhancement activities the sight lines to escape terrain could also be improved. Reduction of conifer in-growth and encouragement of forage production are two treatments conducted in the Lower Wasa Mountain area. The recommended stand-tending treatment for Herbert Face is for 22.2 hectares of old age Douglas fir forest.

Discussion on the Treatment Unit Priorities

The range used by the Wolf Creek or Wasa Mountain herd should be the focus of the initial enhancement activities like the development of Stand Management Prescriptions for selective logging. Douglas fir that is less than 25cm Diameter at Stump Height situated between Wasa Mountain and farm land of Wink Bradford should be slashed to improve sight lines to talus slope. This will create a connection between open-forest habitat and winter range habitat of Rocky Mountain bighorn sheep. It is recommended to treat the badlands of Wolf Creek with a prescribed burn. It is a connection between sheep range above Quartz Lake with habitat on Wasa Mountain. Lazy Lake had a lot of conifer trees which should be hand slashed to keep open-forest conditions. Burns should be conducted on the northern side of the Wasa Mountain Ridge and the upper-facing slopes of Wasa Mountain. In the Estella Mountain it is recommended to hand slash encroaching lodgepole pine and conduct burns through aerial ignition. There are many more recommended treatments in areas including Brewery Ridge, Lewis Creek East,Quartz Lake West, etc.

Conclusion

Rocky Mountain bighorn sheep need open range and clear sight of their escape terrain. Due to forest encroachment some areas can no longer support bighorn sheep. This project aims to create an enhancement plan for Rocky Mountain bighorn sheep areas. Recommended actions include burns in several areas and cutting down or slashing Douglas fir and lodgepole pine. Areas of interest include the Wildhorse area, Premier Ridge area and Estelle area.

  • Source Peter W. Davidson. December 2006. Enhancement Plan : Rocky Mountain Bighorn Sheep Habitat Mause Creek-Premier Lake. Prepared for Columbia Basin Fish and Wildlife Compensation Program. Available at : https://a100.gov.bc.ca/pub/acat/documents/r40122/Enhanc_Rocky_Bighorn_1385743265948_5743263421.pdf [Accessed 03/2021].