Table 7. Slope of the simulated population against time (% population change/yr) for five avian species of management interest based on roadside surveys and on the entire study region. Positive values indicate increasing populations; negative values indicate decreasing populations.
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Species |
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Source of estimate |
Eastern Towhee (Pipilo erythrophthalmus) |
European Starling (Sturnus vulgaris) |
Kentucky Warbler (Oporornis formosus) |
Prairie Warbler (Dendroica discolor) |
Wood Thrush (Hylocichla mustelina) |
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Land cover proportions on the entire landscape |
3.21 (1.15)† |
5.08 (1.08) |
–0.71 (0.21) |
3.36 (2.37) |
–0.43 (0.09) |
Land cover proportions within 50-m buffers |
1.72 (0.41)* |
2.51 (0.31)*** |
–0.76 (0.11)*** |
1.06 (1.44) |
–0.26 (0.05)** |
Land cover proportions within 200-m buffers |
2.06 (0.52) |
3.47 (0.43)*** |
–0.74 (0.09)** |
1.46 (1.63) |
–0.30 (0.06)** |
Land cover proportions within 400-m buffers |
2.68 (0.91) |
4.92 (0.54)*** |
–0.75 (0.14) |
1.99 (1.96) |
–0.30 (0.07)** |
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†The numbers in parentheses are the standard deviations of the regression coefficients, expressed as % change/yr relative to the simulated starting population in 1980.
* P < 0.05, ** P < 0.01, *** P < 0.001 for the slope of the regression for the entire landscape (first row) vs. that for the buffer (last three rows).
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