. La Canadian field-naturaliste. 1971 Stelfox : Mouflons au Canada 1800-1970 113. La figure 6. Une fleur d'hiver le long de la vallée de l'Athabasca, parc national Jasper. Ceci est le résultat de plusieurs années d'utilisation par plus de moutons que la gamme peut prendre en charge. Crédit Photo : A. Loewen, Jasper Service des gardes de parc. maladie a été très probablement la cause de l'épidémie qui s'est produit en même temps dans le parc. Conditions de l'aire est détériorée et les pauvres nutri- tion sans aucun doute les animaux prédisposés à la maladie (Figures 6 et 7). Le Cerf mulet ont été estimées par les directeurs à 1 700 en 1947 (Ban- zone 1947). L e

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. The Canadian field-naturalist. 1971 Stelfox: Bighorn Sheep in Canada 1800-1970 113. Figure 6. A denuded winter range along the Athabasca Valley, Jasper National Park. This results from several years of overuse by more sheep than the range can support. Photo Credit: A. Loewen, Jasper Park Warden Service. disease was very likely the cause of the epidemic which occurred at the same time in Waterton. Deteriorated range conditions and poor nutri- tion undoubtedly predisposed the animals to the disease (Figures 6 and 7). Mule deer were estimated by wardens at 1, 700 in 1947 (Ban- field 1947). The elk population in Waterton was light before 1937 as they apparently did not migrate from the Belly River valley until 1932. Elk within the park in 1945 were estimated at not more than 500 (Banfield 1947). Thus, approximately 1, 000 bighorns, 1, 500 mule deer and elk and 2, 211 livestock, (almost 5, 000 ungulates) were foraging within this 204- square-mile park in 1936. Heavy snows in that year contracted the winter range to about 50 square miles, so the density must have ap- proached 100 ungulates per square mile. Buechner (1960) reported that on bighorn sheep ranges which had been stocked with domestic cattle, sheep and horses, the bighorns disappeared because they were unable to survive on deteriorated ranges. In addition, he believed that domestic stock probably introduced dis- eases harmful to bighorns. Studies during the Banff die-off revealed chronic actinomycosis and "verminous" broncho-pneumonia caused by lungworm (Cowan 1943). Poor range conditions resulting from over- stocking of bighorns and elk in the parks during the late 1930's and early 1940's were described by Clarke (1941), Green (1949), and Cowan (1950). In 1943, when the elk population in Banff was estimated at 3, 500 to 4, 000, Green (1949: 33) stated, "The elk pressure on all ranges, especially those of limited extent, has. Please note that these images are extracted from scanned page images that ma

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