Figure 1.

Conceptual diagram showing geographical extent-of-occurrence by week (circles) for an individual species within the study area from the beginning of spring migration (long dash), through the breeding season (solid), to the end of autumn migration (short dash), and the regions used in three alternative migration scenarios. The regional migration scenario estimates the range of possible associations available to each species, the spring migration scenario estimates associations had species used their spring migration route in the autumn and the autumn migration scenario estimates associations had species used their autumn migration route in the spring (see Material and methods for details on scenarios).