Models of avian richness, species density, abundance, and occurrence for southern Michigan bird communities in switchgrass (n = 15) and prairie patches (n = 15).

†Number of parameters,
‡Model Akaike weight,
*P<0.05≥0.01,
**P<0.01≥0.001,
***P<.001,
nsP>0.05.
The table lists the best models (ΔQAICc or ΔAICc<2.00) for 1) the entire bird community, 2), breeding birds only, and 3) obligate grassland species. P-values associated with model parameters are given. Response variables: AMAS = arthropod biomass; ARIC: arthropod family richness; MPC1: microhabitat principal component 1; MHET: microhabitat heterogeneity index; CROP: biomass crop; PSIZ: log patch size; LPC1/LPC2: landscape principal components; LDIV: landscape diversity index. Landscape composition and LDIV variables are labeled with the relevant spatial scale (radius in meters from center of each patch) at which they are computed.