. La Canadian field-naturaliste. L'histoire naturelle. La pruche de l'Ouest (Tsuga heterophylla). D'autres com- tue les arbres sont la pruche (Tsuga merten- siana), en Alaska (Chamaecyparis nootkatensis), le thuya géant (Thuja plicata), l'Aulne (Alnus rubra) et le Peuplier noir (Populus trichocarpa) (Viereck et Little 1972). La zone restante est la toundra alpine, riverains ou éparpillés de fondrières. De la zone forestière, 75  % était vieille forêt au début des années 1980 (Alaback, 1982). Les vieilles forêts ont mul- tilayered les marquises avec de nombreuses lacunes, et l'âge des arbres dominants dépasse 150 ans (Alaback

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. The Canadian field-naturalist. Natural history. Western Hemlock {Tsuga heterophylla). Other com- mon trees are Mountain Hemlock (Tsuga merten- siana), Alaska Cedar (Chamaecyparis nootkatensis), Western Redcedar (Thuja plicata), Red Alder (Alnus rubra), and Black Cottonwood (Populus trichocarpa) (Viereck and Little 1972). The remaining area is alpine tundra, riparian, or scattered muskeg. Of the forested area, 75% was old-growth forest in the early 1980s (Alaback 1982). Old-growth forests have mul- tilayered canopies with numerous gaps, and the age of dominant trees exceeds 150 years (Alaback 1982; Schoen et al. 1988). The understory of old-growth forests is covered by coarse woody debris and vege- tation such as ferns, mosses, lichens, fungi, herbs, and shrubs (Alaback 1982; Spies and Franklin 1988), and provides a mosaic of unique habitats for many species of plants and animals. Although Prince of Wales Island (POW; 6700 km2) and adjacent islands support larger populations of terrestrial vertebrates than smaller islands in the region, the number of species is limited (e.g., no lagomorphs occur on POW or adjacent islands). Terrestrial mammals relevant to our study include the Wolf, Black Bear, River Otter, Mink (Mustela vison), Marten, Short-tailed Weasel (Mustela erminea), Sitka Black-tailed Deer, Beaver, and small rodents (Microtus spp. and Peromyscus spp.). The natural landscapes of southeastern Alaska have been markedly altered by human activities such as timber harvesting. Clear-cut logging has been practiced on old-growth forests in the region for the past several decades. Since the early 1900s, and more intensively in the last 30 years, > 400 km2 of high-volume old-growth forests on POW (6% of the island) have been logged (Schoen et al. 1988; Yeo and Peek 1992).. Figure 2. Study area and general locations of Wolf pack home ranges for categorizing collection locations of feces. Figure 3. Calculation of two indices describing occurrence of food items in Wo

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