Plant and Bird Communities of Native Prairie and Introduced Eurasian Vegetation in Manitoba, Canada

Abstract

Abstract: Large areas of North American prairie are dominated by Eurasian plant species introduced either for range improvement or accidentally as weeds. We examined the impact of introduced plants on both native vegetation and bird communities in a mosaic of North American mixed‐grass prairie and Eurasian vegetation. We established ten transects five in areas of native prairie and five in areas dominated by introduced plant species. Each transect comprised five sampling stations separated by 100 m. Vegetation was sampled in four 0.5m2 quadrats at each station. The cooers of eight of the ten most common plant species varied significantly (p < 0.05) between native and introduced vegetation. One common native plans Andropogon scoparius, was absent in introduced vegetation Singing birds were identified to species at each station on three occasions during the breeding season All bird species found were native to prairie. The total number of birds did not vary between vegetation types Two out of eight bird species, upland sandpiper and Sprague's pipit were signifcantly more abundant in native prairie than in introduced vegetation No bird species were significantly more common in introduced vegetation. A correlation matrix calculated for all bird species and the ten most abundant plant species divided the bird community into two groups. The first group (western meadow lark, upland sandpiper, Sprague's pipit, Baird's sparrow and savannah sparrow) was positively correlated with native plant species and negatively with introduced plants, while the second (vesper sparrow, clay‐colored sparrow, and grasshopper sparrow) was negatively correlated with native species and positively correlated with introduced Discriminant analysis separated transects from native and Eurasian vegetation on the basis of their respective bird communities. The results illustrate that the introduction of Eurasian plant species to North American prairie not only replaces the native plant community, but also produces significant changes in the species composition of a higher trophic level.