| Summary: | The wolf (Canis lupus)/mountain caribou (Rangifer tarandus caribou) spatial separation model
(Seip 1992a) was examined in highland and mountainous areas of east central and southeastern
British Columbia to determine the influence of wolves on mountain caribou ecology. Three key
elements investigated were: the importance of wolf predation as a mountain caribou mortality
factor, the elevational relationships of mountain caribou, wolves, and moose (Alces alces), and
the seasonal dietary importance of moose to wolves.
Mountain caribou mortality data from the Columbia Mountains and Quesnel Lake supported
the hypothesis that wolf predation is greater in highland than in mountainous areas. Wolf
predation was the main mortality factor of caribou in the highlands around Quesnel Lake, but
was a minor factor in the other three study areas. Wolf predation at Quesnel Lake occurred
primarily during summer/fall at low elevations.
Mountain caribou, wolf and moose radio-telemetry data suggested that wolves in both
highland and mountainous areas are more closely associated elevationally with moose than
caribou throughout the year. Caribou in highland areas appeared as adept as those in rugged
mountains at spacing elevationally away from wolves during all seasons. Significant elevational
overlap between wolves and caribou occurred only in the rugged Columbia Mountains, and then,
only during summer/fall.
Wolf scats from the Columbia Mountains indicated that mountain caribou were of lesser
dietary importance than moose to wolves throughout the year. Moose, particularly in winter,
were the main diet item of wolves. Beaver was an important dietary item of wolves during
summer/fall.
Elevational separation appears inadequate in explaining the variation in wolf predation on
mountain caribou in the highland and mountainous study areas. Differences in wolf densities and
the relative densities of moose and caribou may be the main factors influencing the susceptibility
of mountain caribou to wolf predation. It is recommended that studies be conducted in both
topography types across a wide range of caribou and moose densities to better explain the
influence of wolves on mountain caribou ecology. In addition, it will be necessary to compare the
geographic distribution of mountain caribou and wolves to assess if geographic rather than
elevational separation occurs. Determining how timber harvesting impacts the numerical and
spatial responses of wolves, mountain caribou and moose is also recommended.
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