A study of canyon-dwelling mountain goats in relation to proposed hydroelectric development in northwestern British Columbia, Canada

Abstract

Preliminary ecological relationships between a resident mountain goat Oreamnos americanus population and a proposed hydroelectric development were investigated in 1979 and 1980 along the Stikine river, in northwestern British Columbia. Population size was estimated at 316 animals, distributed along 54 km of the canyon. Steep canyon walls were utilized predominantly during summer. Adjacent forested areas became increasingly important during winter when icy conditions prevailed within the canyon. Spatial relationships of kidding and rutting areas, location of mineral licks, and utilization of plant life formations are also summarized. Localized goat mortality and possible temporary range abandonment observed in the proposed Site Z dam area may have resulted from 1978 and 1979 hydroelectric exploration activities. Proposed construction activities could similarly affect up to 56 goats. Proposed Tanzilla and Site Z reservoirs could reduce the 1979 study area population by about 17%, or 55 goats with the greatest flooding impact occurring in the Site Z reservoir. Major mitigation measures involve design and control of land and aerial access, and reduction of noise and related disturbances during critical biological periods. Examples are given for possible compensation measures including range enhancement, establishment of goast in vacant habitat, and development of viewing facilities. Resultant land and water access can provide long-term opportunities for increased hunter harvest and other non-consumptive uses of the animal resource, if properly regulated.