AGE – BEST CRITERIA:

• If present, juv GC (commonly 0-4 juv GC unmoulted) are detectable by being warmer brown, slightly more worn and with looser texture. If all GC are moulted, there is still a  contrast between retained juv PC and GC (less easily detected). Note that outermost GC1 sometimes is slightly browner than other GC (even within the same generation), and an assessment of feather structure is recommended.
• Juv PC usually show a looser texture and browner edges compared to adult birds.
• Juv AL are rather brownish (and in the same state of wear as PC), sometimes contrasting with post-juv AL showing fresher greyish or olive edges and a glossy dark/black centre.
• Juv TT show a looser texture and a slightly browner ground colour and contrast with post-juv GC. Any post-juv TT are recognized by being denser with a darker olive ground colour, similar to post-juv GC.
• Juv RR (as well as PP) are generally narrower, slightly more pointed and show a poorer feather quality (less dense, less gloss and with a brownish ground colour).
• Iris is often helpful during autumn – most 1cy have a rather cold dark grey iris, sometimes with slight brownish tint.

• Whole plumage fresh, lacking moult contrasts.
• PC are dense and often show fresh greyish or olive edges.
• AL show glossy dark centres with fresh greyish or olive edges.
• TT show a dense texture and a more olive ground colour, similar to the GC.
• RR (as well as PP) are broader, and in better condition (denser, darker and with more gloss). 
• Iris is warmer brown.