. The Canadian field-naturalist. Natural history. 2002 Prescott, Norton, and Michaud: Night Surveys of Rails 413. O Yellow Rail ^ Virginia Rail Figure 3. Sites where Yellow and Virginia Rails were found during call playback surveys in 2000. See Tables 1 and 2 for additional details. Yellow Rails were detected significantly more often than expected in sedge and "mixed" (cattail/ bulrush/sedge) wetlands, and less often in basins dominated by cattail or bulrush (X"= , df = 3, p < ). Furthermore, occupied basins were most likely to be seasonal, as opposed to semipermanent
. The Canadian field-naturalist. Natural history. 2002 Prescott, Norton, and Michaud: Night Surveys of Rails 413. O Yellow Rail ^ Virginia Rail Figure 3. Sites where Yellow and Virginia Rails were found during call playback surveys in 2000. See Tables 1 and 2 for additional details. Yellow Rails were detected significantly more often than expected in sedge and "mixed" (cattail/ bulrush/sedge) wetlands, and less often in basins dominated by cattail or bulrush (X"= , df = 3, p < ). Furthermore, occupied basins were most likely to be seasonal, as opposed to semipermanent or permanent (x^= , df = 2, p < ), and tended to have less open water ( ± [SE]%) than sites where birds were not detected ( ± %; T = , p ), but preferred wetlands with more open water ( ± vs. ± ; T=, p<) and less shrub ( ± vs. ± ; T = , p < ). Furthermore, birds were found more often on permanent or semipermanent wetlands than on seasonal waterbodies (X" = , df = 2, p 90% of all the sites were only visited on a single occasion which would have detected occupancy with no better than 75% certainty (Bart et al. 1984; Gibbs and Melvin 1993). Nevertheless, it is apparent that both species of rails are relatively uncommon within their Alberta range. Occupancy rates at historical sites were also low. This is especially true of Yellow Rails (three of 42 sites surveyed), and may reflect the observed preference of birds for seasonal wet- lands (fsee also Boukhout (1995) and references therein)] which can vary greatly in condition from. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Ottawa Field-Naturalists' Club. Ottawa, Ottawa Field-Naturalists' Club
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