Figure 4. Inter-specific body mass variation during remigial moult.

Changes in mean body mass of birds (as percentage of initial weight) based on the percentage growth of the 9^th primary for 5 seaduck species; Harlequin Ducks (HADU), Long-tailed Ducks (LTDU), Surf Scoters (SUSC), White-winged Scoters (WWSC) and Common Eiders (COEI) with (A) representing males and (B) females. Phase 0 corresponds to the value of initial weight before the shedding of flight feathers, Phase I represents feather emergence and the start of feather growth, Phase II corresponds to the period of fast feather growth rate and where maximal growth rate is reached, Phase III is the period of the first slowing down of growth rate, Phase IV corresponds to the second slowing down of growth rate and the period during which birds are able to fly again, Phase V is the end of the remigial moult when final length of P9 is reached.