Helminths of the grizzly bear, Ursus arctos L., in northern Canada

Abstract
Twenty-nine grizzly bears, Ursus arctos L., killed between 1965 and 1967 in northwestern Canada, principally the Yukon Territory, were examined for helminths. The authors found six species of helminths with the following prevalence: Baylisascaris transfuga (Rudolphi, 1819) Sprent, 1968 in 16 of 21 bears; Dochmoides yukonensis Wolfgang, 1956 in 10 of 21; Dirofilaria ursi Yamaguti, 1941 in 3 of 27; Trichnella spiralis (Owen, 1835) Railliet, 1896 in21 of 24; Diphyllobolhrium (?) ursi Rausch, 1954 provis. in 3 of 21; and Taenia krabbei Moniez, 1879 in 2 of 21 bears. These findings are discussed in the light of other reports, and constitute the first record of helminths from grizzly bears in Canada.