Fig. 4

Variation in departure timing of common redstarts (grey) and European robins (orange) from Helgoland during autumn migration. Departure timing is given as (a, c) proportion of night at departure and (b, d) departure time in minutes after sunset for all birds (a, b) and for birds departing during the first night after capture only (c, d). Box plots show the 5th, 25th, 50th, 75th, 95th percentile and outliers (filled dots). Numbers at the bottom of the boxes represent sample sizes