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.

Species
Source of estimate Eastern Towhee
(Pipilo erythrophthalmus)
European Starling
(Sturnus vulgaris)
Kentucky Warbler
(Oporornis formosus)
Prairie Warbler
(Dendroica discolor)
Wood Thrush
(Hylocichla mustelina)
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)**
†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).