Population surveys and mortality monitoring for mountain caribou, an ecotype of woodland caribou (Rangifer tarandus caribou), were conducted in the southern Purcell Mountains of British Columbia from 1994 to 1998. Results indicated that this subpopulation was declining, with annual growth rates ranging from 0.82 to 0.88. This was a result of low calf recruitment (late-winter ratios of 0.00–0.13 calves per adult) and high adult mortality (mean annual rate = 0.27). Reasons for low recruitment were unknown, but most adult mortality was attributed to predation, particularly by cougars (Felis concolor). The difference in mortality rate between sexes was nonsignificant (P = 0.14), but was consistent with increasing bull:cow ratios observed during the study. The southern portion of the study area had more recent cutblocks and fires (i.e., forests <40 years), greater road density, and more fragmentation than the northern portion. Caribou mortality was also significantly greater in the south than the north (P = 0.03).
Kinley, Trevor A., Apps, Clayton D.. 1999. Population Status and Mortality of Mountain Caribou in the Southern Purcell Mountains, British Columbia (in Proc. Conference Biology & Management of Species and Habitats at Risk). Ministry of Environment, Lands and Parks; University College of the Cariboo. Proceedings - Conference Biology & Management