AGE – BEST CRITERIA:

Since the pre-br moult is rather restricted, the characters used during autumn are still valid. Pattern and moult status of GC is generally easy to assess. In 2cy, a moult contrast is present among inner GC. However, quite many birds of both age classes show a surprisingly fresh innermost GC9-10 (which may be mistaken for pre-br feather), probably best explained by its more protected position. Note that the general wear is highly variable within both age categories of this species, making PP and RR difficult to use for ageing.

2cy:

• Most birds (at Ottenby 97%) included 1-3 inner GC in the post-juvenile moult. Juvenile GC show a looser structure and are rather worn. Remnants of the rusty wedge-shaped spot at the feather tip are usually still appearant on central and outer GC. Post-juv inner GC are denser, show darker grey centres and olive-brown edges.
• Juv PC may be rather worn and frayed, but the difference with ad PC is not always obvious. In many young birds the pale wedge-shaped GC-tips continues out onto the inner PC.
• Juv TT are usually worn, brownish and dry in appearance, often slightly narrower and more pointed than ad type feathers.
• The tail is often difficult to assess, and the wear in the juv RR seem to vary extensively (depending on wintering habitat?).

3cy+:

• Whole plumage uniform but, compared to other small thrushes, often surprisingly worn (incl. PP, TT and RR).
• GC are uniformly olive-brown with no (or only weak) pale tips.
• PC are slightly denser and usually in somewhat better condition.
• TT are usually rather worn but still look slightly denser in structure and more olive (rather than brownish).
• The tail is very variable in wear and often difficult to assess.