AGE – BEST CRITERIA:
Autumn criterias are still applicable, though 2cy are more affected to wear during the winter than adult. Moult contrast present in the wing of 1cy, generally among outer GC, or between GC and PC. A few birds also show contrasts in TT or RR. Adult birds show a uniform plumage.
2cy:
- Often show moult contrast in outer GC: Fresh post-juvenile inner GC are darker greyish black and usually show a wide yellowish-white tip in contrast to the slightly more worn, greyish, juvenile outer GC with narrow white tips. Others have included all GC in the moult, and the contrast is then found towards the still juvenile PC.
- Juvenile PC are generally slightly more narrow, more worn in tips and edges and less brightly coloured in the green/grey edge of outer vane (though males often show all black PC). A slight variation occur, and some individuals may be a bit more difficult to assess than other.
- Juvenile RR are somewhat variable, but generally slightly more narrow and pointed in the tips and show a juvenile quality to the feather. A few individuals have moulted single or some RR and then exhibit moult contrast among RR.
- Most individuals show uniformly juvenile TT, but a few may include one to all feathers. Post-juvenile TT are fresh and show a more contrasting pattern with a blackish centre and deeper rusty or buff edge (similar to the post-juvenile inner GC), contrasting well to unmoulted TT and inner SS.
3cy+:
- Uniform plumage lacking any moult contrast (though rare occasions of retained/forgotten feathers are known).
- Whole wing and tail (esp. PC, PP and RR) in better condition with broader and denser feathers, more blackish in colour and with better gloss (esp. in males).
- Tips of RR generally more blunt and broader.