| Summary: | This study provided information on the species composition of the riparian bird community, evaluated the impact of grazing on avian species richness and abundance, and assessed avian habitat relationships relative to grazing in the Pembina Valley, Manitoba. Birds were censused using unlimited-radius counts at 27 grazed and 28 ungrazed point count stations through the month of June 1997. Fifteen habitat variables were measured in five 0.04 ha (11.3m, radius) circular plots at 14 ungrazed and 15 grazed point count stations. To some extent, livestock grazing was found to influence these variables and produce sites with comparatively lower vegetation densities. Bird species richness, abundance and diversity were similar on grazed and ungrazed treatments; however, bird species composition and representation of foraging and nesting guilds differed. Patchiness of vegetation on grazed sites continued to provide habitat for many bird species. (Abstract shortened by UMI.)
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