AGE – BEST CRITERIA:
Autumn criterias are still applicable. In 2cy, all SS are uniformly juvenile, and show juvenile type barring. Older age classes show (most or all) SS with adult type barring, and in c. 35% of the birds at Ottenby, two different generations of SS are present. Two to four age categories are discernable, depending on the extent of the post-breeding moult of the individual.
3cy+ March (male). SS are uniformly post-breeding, showing no moult contrast (if a moult contrast is present, the age may be able to specify to 3cy or 4cy+). The SS show four adult type bars, rather broad and dark blackish-brown. The ground colour of the SS is rather cold greyish-brown. 
3cy April (male). Birds with less extensive moult of remiges show moult contrasts in the arm. This bird shows a largely moulted arm, but two SS are worn, paler and slightly longer. These unmoulted two SS are of typical juvenile type, showing five narrow and paler brown bars, in contrast to the adjecent adult type SS showing adult pattern with four broad and darker bars. 
Potential 4cy+ April (male). This individual shows an S4 with a slightly differing pattern, implying a moult contrast. But difference in wear to adjecent SS is not obvious, and we prefer to be careful and to book this bird as 3cy+. However, if the S4 should be from last year's post-breeding generation, this bird must be 4cy+, since the feather show adult type barring. 
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