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

Authors

  • SCOTT D. WILSON,

    Corresponding author
    1. Department of Botany, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
      *Correspondence should be sent to Scott D. Wilson at the following address: Ecosystem Dynamics Group, Research School of Biological Science, The Australian National University, GPO Box 475, Canberra, ACT 2601, Australia
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  • JOYCE W. BELCHER

    1. Department of Botany, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
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    • Department of Biology, University of Ottawa, Ottawa, Ontario, KIN 6N5, Canada.


*Correspondence should be sent to Scott D. Wilson at the following address: Ecosystem Dynamics Group, Research School of Biological Science, The Australian National University, GPO Box 475, Canberra, ACT 2601, Australia

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.

Abstract

Resumen: Las plantas Euroasiaticas, que ban sido introducidas ya sea para el mejoramiento de la pradera o aceiden talmente como mala bierba, dorminan una gran área de las praderas Norteamericanas. Se examinó el impacto que tienen las plantas introducidas en la vegetación nativa y en comunidades de aves en un mosaico de praderas de pasto mezclado y vegetación Euroasiatica Diez transectos fueron establecidos, cinco en regiones con praderas nativas y cinco en áreas dominadas por especies de plantas introducidas Cada transecto incluyo cinco estaciones de muestreo separadas por 100 metros La vegetación fue muestreada en cada estación en cuatro cuudrantes de 0.5m2. La cobertuda de ocbo de diez de las especies de plantas mas comunes variaron considerablemente (P < 0.05) entre la uegetación nativa y la introducida Una planta native comun, Andropogon Scoparius, estuvo ausente en la uegetación introducida Aves de canto fueron identifacadas en cada estación en tres ocasiones durante la estación de reproducción Todas las especies de aves encontradas son originarias de las praderas El numero total de aves no vario entre los twos de vegetación Dos especies de aves (upland sandpiper y Sprague's pipit), de un total de ocbo, fueron significativamente máS comunes en la pradera nativa que en la vegetación introducida Una de correlación calculada para todas las especies de aves y para las diez especies de plantas mas abundantes dividio la comunidad de aves en dos grupos En el primero, (western meadowlark upland sandpiper, Sprague's pipit Baird's sparrow y savannah sparrow) se correlaciona en forma positiva con especies de plantas nativas y de forma negativa con plantas introducidas, mientras que en el Segundo grupo (vesper, sparrow clay colored sparrow y grasshopper sparrow), se correlaciona negativamente con especies nativas y positivamente con especies introducidas. Un análisis discriminativo, separo transectos de vegatación nutiva y Euroasiatica basandose en sus respectivas comunidades de aves Los resultados ilustran que la introducción de especies de plantas Euroasiaticas a las praderas Norteamericanas no solamente reemplaza la comunidad nativa de plantas, sino que tambien produce cambios signifcativos en la composición de las especies en niveles troficos mas altos.

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