Figure 2.

Behaviour in relation to crosswinds along the migratory route for two species of raptors. Every segment represents a migratory journey of 1–4 days. The colours of the segments indicate whether it was an occasion of drift (green), compensation (blue), or overcompensation (orange). For classification criteria, see figure 1 and main text. (a) Ospreys in autumn, (b) ospreys in spring, (c) marsh harriers in autumn and (d) marsh harriers in spring. The corresponding bars indicate the frequency distribution of different responses to crosswind for different latitudinal bands (°N, y-axis). Numbers to the right of the bars indicate sample sizes.