Data based on 686 first year Song Thrushes ringed in northeastern Spain show that most young birds (93%) moult 1-5 greater coverts; these birds are easily aged according to the pattern of the tips. Birds moulting 6-8 greater coverts are scarce (4%) and are more difficult to age using the same criterion, but differences in general colour between moulted and unmoulted feathers, colour of primary coverts and rectrix shape can override this dificulty.
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