Fig. 1

The relative proportion of C-strain, R-strain, and putative hybrid individuals collected at each location. When locations were sampled at multiple timepoints, we did not observe any notable differences in strain composition across collections, so all individuals throughout the year are pooled within each location. Background shading designates western (clear), central (blue), and eastern (red) flyways. Hashed background designated area of intermixing between the central and eastern flyways