Fig. 1

The breeding and fall migratory range for Blackpoll Warblers. The blue shaded region represents the breeding range, and the dashed lines represents their fall migratory route. The black rectangle signifies the inset region of the Gulf of Maine, and the capture locations are within the open blue circle. All automated radio telemetry towers in the Motus array during fall 2014 & fall 2015 are marked with red dots. The dark gray contours represent the isoclines derived from the isoscape in [71]. The Blackpoll Warbler breeding range was provided by BirdLife International (2014)