No abstract

Telemetry, sightings, and tracks in snow from 1978–81, with subsequent observations until 1991, showed that woodland caribou (Rangifer tarandus caribou) did not use cut portions of traditional wintering areas for 12 years after cutting. Two attempts by management personnel to modify commercial cutting patterns for caribou failed to prevent abandoning cut areas. In four instances where entire wintering areas were cut, caribou sightings and tracks decreased drastically or ceased entirely. Caribou in unlogged areas have shown no similar declines. Minimal efforts to ensure caribou survival in commercial forests should include deferral of cutting in caribou wintering areas, protection of calving areas, and accelerated research. Keywords: woodland caribou, forest management, threatened population, wildlife conservation

A literature review points to predation as the proximate factor controlling woodland caribou (Rangifer tarandus caribou) populations in most cases, but that finding does not obviate the need for caribou to be included in forest management. Managers must consider the indirect effects of forest operations on caribou through their impacts on caribou mortality factors, such as predation. Lichens remain important. Habitat destruction may in some cases be the ultimate cause of population decline. Reactions of caribou to disturbance vary, and remain controversial; more research is needed. Multiple resource managers of boreal commercial forests should identify sensitive components of caribou range -calving grounds, rutting locations, wintering areas, and travel routes among them -and prescribe for these areas in forest management plans. Ways of accommodating caribou in commercial forests are not well established, but some examples suggest how this might be done. Most importantly, areas that have been proven by their continued use to contain all necessary requirements for caribou survival should not be physically altered until their essential qualities and functions are better understood.

This paper explores mechanisms of coexistence for woodland caribou (Rangifer tarandus caribou) and moose (Akes alcei) preyed upon by gray wolves (Canis lupus) in northern Ontario. Autocorrelation analysis of winter track locations showed habitat partitioning by caribou and moose. Numbers of Delaunay link edges for moose-wolves did not differ significantly from what would be expected by random process, but those for caribou-wolves were significantly fewer. Thus, habitat partitioning provided implicit refuges that put greater distances between caribou and wolves, presumably decreasing prédation on the caribou. Yet, direct competition cannot be ruled out; both apparent and direct competition may be involved in real-life situations. A synthesis including both explanations fits ecological theory, as well as current understanding about caribou ecology.

Forest management guidelines for woodland caribou (Rangifer tarandus caribou) in Ontario need to be re-examined in light of the finding that caribou partition habitat with moose (Alces alces), partly to find virtual refuges from pre¬ dation by gray wolves (Canis lupus). Forest-wide guidelines seem inappropriate for a species that is widely scattered and little known. Management should concentrate on and around currently used virtual refuges to ensure their continued habitability. Cutting these areas may force the caribou into places with higher densities of predators; winter use of roads might bring poachers, increased wolf entry, and accidents. A proposal for 100 km 2 clear-cuts scheduled over 60+ years across the forest landscape would probably minimize moose/wolf densities in the long run as intended, but because of habitat partitioning might forfeit any benefits to caribou in the short-term. Sharply reducing moose densities near areas where caribou have sought refuge might incline wolves to switch to caribou. Cutting beyond caribou winter refuge areas should aim at maintaining current moose densities to prevent wolves from switching prey species. Operations level manipulation of the forest around each wintering area should provide winter habitat for the future, while treatment replications with controls across the whole forest would provide reliable knowledge about which approaches work best. The remainder of the forest should be managed to maintain suitable densities of all other species.