2cy+ female, September. Due to moult timing and sequence, some individuals show considerable differences in wear and bleaching in their plumage, particularly the SS, which may be erroneously interpreted as two different generations. In this individual, for example, S4 looks fresher and bluer than S5. This, however, perfectly matches with the moult order of the SS: S4 is one of the last feathers to be moulted while S5 is one of the first, hence why they look so different (see ageing criteria for more information). [6224992]