Fig. 3

Comparison of day length (a), ambient temperature (b), scaled atmospheric pressure (c), cloud cover (d), tailwind assistance (e) and crosswind (f) at departure nights during autumn migration between blackbird populations. Black solid lines represent the median, boxes represent first and third quartiles, and whiskers describe the 95% confidence intervals. The dashed red line in (c) represents mean atmospheric pressure during the entire departure window, while it marks the absence of tail and crosswinds in (e) and (f). Populations that were identified as different via post hoc tests are joined by brackets noted with the corresponding significant levels (* ≤ 0.05, ** ≤ 0.01, ***≤  0.001)