Best generalized linear mixed models (GLMM) describing the abundance of the 10 most numerous bird species during the winter.

The Akaike information criterion score (AICc), the -2log, difference between the given model and the most parsimonious model (Δ) and the Akaike weight (w) are listed. Explanation of variable codes: Feeders—number of bird feeders, CitySize—human population size in the city, Month—month of survey (December vs. January), Environment—type of the environment (urban vs. rural), Longitude—geographical longitude, PCA1—the first principal component of environmental variables describing the gradient of increasing proportion of open agricultural habitats, PCA2—the second principal component of environmental variables describing gradient from semi-natural grasslands to intensively managed amenity grasses.Best generalized linear mixed models (GLMM) describing the abundance of the 10 most numerous bird species during the winter.