Fig. 1

Energy stores of common redstarts (grey) and European robins (orange) at the time of capture. Box plots show the 5th, 25th, 50th, 75th, 95th percentile and one outlier (filled dot). Raw data are presented as open circles indicating individuals departing on the night after capture or stars depicting individuals staying more than 1Â day on Helgoland. Numbers on the left side of the box represent sample sizes