Table 1.
Variable relative importance weights and weighted parameter estimates.
Figure 1.
Invasion distance and model type.
Boxplots of distance of a site from the original introduction point grouped by population trajectory type for the Christmas Bird Count (blue) and the Breeding Bird Survey (orange).
Figure 2.
Carrying capacities and growth rates.
Map of all (a) Christmas Bird Count circles (blue) and Breeding Bird Survey routes (orange) used in carrying capacity analysis scaled by estimated carrying capacity, k (b) Christmas Bird Count circles (blue) and Breeding Bird Survey routes (orange) used in growth rate analyses with the sizes of each location’s point scaled by estimated population growth rate, r. Minimum and maximum symbol sizes and their meanings are given in the legend of each figure panel.
Figure 3.
Linear predictors of carrying capacities and growth rates.
Univariate plots of the strongest predictor variables for: (a) Christmas Bird Count (CBC) carrying capacity versus percent developed low intensity cover, (b) Breeding Bird Survey (BBS) carrying capacity versus minimum temperature of the coldest month (°C); and population growth rate: (c) CBC population growth rate versus invasion distance, (d) BBS population growth rate versus average annual temperature (°C).
Table 2.
Cross Validation Results.
Figure 4.
Carrying capacity prediction map.
Map of predicted carrying capacity of the Eurasian Collared-Dove across the contiguous United States (Albers Equal Area Conic projection) based on the modeled relationships between Breeding Bird Survey population trajectories and climate and land cover data (see Table 1). Individual cells are 0.5° in each direction, and values represent the expected number of individuals observed on a BBS route within each cell for populations that have reached their carrying capacity.