Distribution


The wolf has one of the broadest distributions of any mammal. In British Columbia it is a year-round resident occurring in all forested regions of the province (found in all ecoprovinces and biogeoclimatic zones), including Vancouver Island and some adjacent islands. However, it is not found on the Queen Charlotte Islands and is only occasionally present in areas along the Canada/USA boundary. In recent years, wolf sightings have become more common in the east Kootenay region of southeastern B.C., suggesting that wolves may be recolonizing this area from the northern Rocky Mountains.

Status

Population numbers of wolves in B.C. are variable, at an estimated 7500 animals. Wolf numbers fluctuate with prey populations. In areas close to human settlement or agricultural operations, numbers are expected to decline over the long term. Moderate to high wolf populations occur in the north and central interior and in coastal areas, while low populations occur at higher elevations and within the southern parts of its range (Tompa 1983). The wolf is on the provincial Yellow list.

Formerly, Nagorsen (1990) recognized three subspecies of Canus lupus in the province. However, following a re-evaluation of wolf taxonomy by Nowak (1995), two subspecies are currently recognized in B.C.: C. lupus nubilus and C. lupus occidentalis (Nagorsen, 1998). Currently, the distributions of these subspecies can best be described in general terms. C. lupus nubilus is found on both Vancouver Island and coastal B.C. while C. lupus occidentalis occurs throughout the interior.

Territory Size and Population Densities

Wolves travel extensively in their search for food. Territory size and movement patterns are highly variable depending on pack size, availability of prey species, physiography, and seasonality (Fritts and Mech 1981, Ballard et al. 1987). In northwestern Minnesota, Fritts and Mech (1981) found territory sizes ranging from 195 to 555 km2 (a density of 7 to 30 wolves/1000 km2); in south to central Alaska, Ballard et al. (1987) found territory sizes from 943 to 2541 km2 (a density of 2.6 to 10.3 wolves/1000 km2); in the southern Yukon, Hayes (1992) found territory sizes of 583 to 794 km2 (a density of 10 to 12 wolves/1000 km2); in the Kenai Peninsula, Alaska, Peterson et al. (1984) found average territory sizes of 638 km2 (with a density of 18 wolves/1000 km2); in northwestern B.C., Bergerud and Elliot (1986) found wolf densities of 5 to 11 wolves/1000 km2; and in coastal forests of northern Vancouver Island, Atkinson and Janz (1994) found territory sizes from 100 to 400 km2 (a density of 4 to 43 wolves/1000 km2).

Lone wolves and dispersing animals can travel great distances and have accordingly large territory sizes. Peterson et al. (1984) found that recolonizing wolf pairs on the Kenai Peninsula, Alaska had 3 to 4 times larger areas per wolf than members of larger packs. Straight-line dispersal distances can be in the hundreds of kilometres. Ballard et al. (1987) described a pack of 3 non-denning males which traversed an area of 3077 km2, and Hayes et al. (1991) found the average linear distance that wolves dispersed was 90 km (range 10 to 140 km).

Diet and Habitat Use

Wolves are carnivores, preying mainly on adult ungulates, ungulate calves and fawns, and beaver (Scott and Shackleton 1980, Peterson et al. 1984, Hatter 1988, Hayes et al. 1991). To a lesser extent, they will also eat hares, small rodents such as mice and voles, and occasionally birds. Habitat utilization is primarily influenced by availability of prey species and physiography (Fritts and Mech 1981, Ballard et al. 1987).

In summer a pack's affinity for a particular denning area also influences habitat use. Dens can be excavated in banks or shallow hillsides, or can be among the roots of large trees, in hollow logs, or in rock crevices. Maternity dens are often used by the same pack year after year, and summer homesites where pups are raised are usually within a few kilometres from the den. Thereafter, pup activities center around a succession of homesites, progressively farther from the den as mother and pups eventually rendezvous with the pack (Van Ballenberghe et al. 1975, Peterson 1977, Peterson et al. 1984, Ballard et al. 1987).

In winter, wolves tend to be found in areas associated with ungulate winter ranges (Fritts and Mech 1981), and often use frozen waterways as travel corridors where snow accumulation can be less. Intensity of use patterns within territories is greatly influenced by physiography. Areas such as treeless marshes or homogeneous coniferous cover tend to be used less by wolves (Fritts and Mech 1981). Wolves routinely patrol their territories, scent-marking the peripheries by urinating and defecating (Peters and Mech 1975). Extraterritorial movements and dispersal by pack members can occur throughout the year, but are common in February and early March (coinciding with the breeding season), and during the summer (coinciding with whelping).