A Spatial Analysis of Factors Affecting Nesting Success of Shorebirds in the Canadian Prairies
2013
Garvey, Mary E. | Nol, Erica | Howerter, David W. | Armstrong, Llwellyn M.
Conversion of natural grassland to cropland has been postulated as a cause for population declines among grassland birds. We evaluated nest-site habitat characteristics and landscape composition for three species of prairie-breeding shorebirds nesting across the agricultural landscape of prairie Canada. Nests of the Upland Sandpiper (Bartramia longicauda) and Willet (Tringa semipalmata) were found disproportionately in natural grazed (57%) or natural idled (21%) patches, whereas Marbled Godwit (Limosa fedoa) nests were in habitats in proportion to their availability on the landscape. We examined multiple landscape variables (proportions of crop, natural idled, natural grazed, and wetland habitats, edge density, and patch area) across a broad geographic scale, using relatively large samples of nests, and found no strong relationships. Neither nest-site habitat characteristics nor landscape-level effects influenced daily survival rates of Upland Sandpiper or Willet nests. Variation in landscape composition at three different spatial scales (200, 600, and 2000 m) also did not influence daily nest-survival rates. To adequately inform land-use management programs aimed at shorebird conservation, further research should examine site-selection patterns and characteristics of nest sites that maximize survival of chicks and adults during subsequent stages in reproduction.
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