AGE – BEST CRITERIA:

Following the post-juv moult, a moult contrast is present in the wing of 1cy. It is generally situated within GC, but in more advance birds it may be found between post-juv GC and juv PC/TT or within RR or TT. Ad birds show a uniform and freshly moulted plumage without contrasts. Note that, although differences in wear is rather apparent from mid autum, there is a rather wide range of variation in the amount of wear within each age-group.

1cy:

• Often show moult contrast in GC: Post-juv inner GC are denser and often clearly longer and broader than slightly more worn juv outer GC, edged deeper chestnut-brown, with brown colour of outer vane diffusely bleeding onto shaft of feathers. Compared to ad-type GC, juv GC show looser structure with narrower and more sharply offset pale buffish edges. Some birds may have included all GC, and the contrast is then found towards the still juv PC. Word of caution: Amount of black in outer vane increases progressively from inner to outer feathers regardless of generation; note juv-like pattern on ad-type outermost GC (GC1-2), showing narrower brown fringe sharply offset from black centre of the feather, not reaching shaft. Fringe of ad-type GC1 typically paler brown than adjacent feathers, creating false contrast.
• Juv CC shorter and more frayed in tip than ad-type, with warm brown or straw-coloured fringe, similar to juv GC.
• Single TT may be included in the post-juv moult. Post-juv TT are fresh, broad and dense, showing deeper brown outer vanes and darker blackish inner vanes than the slightly worn juv ones. The latter are typically narrower and show paler buff fringes to outer vanes, with inner vanes being duller brown. Juv TT may also contrast well to moulted post-juv inner GC.
• In general, juv PC are less dense, narrower and more pointed than ad-type. Blackish colour is warmer and duller, with pale tips slightly worn and brownish. Fringes to outer PC are less brightly coloured than ad-type, often warm buffish or off-white, contrasting with white colour on outer vanes of inner PP. Fringes to inner PC are often warmer brown. However, due to variation in both age-groups, PC are often difficult to use for ageing.
• Juv RR are slightly narrower and more pointed than ad ones, generally showing noticeable wear from September onwards. Some individuals may have replaced single or several (or even all) RR and then either exhibit moult contrasts or a full ad-type tail.
• Iris rather neutral grey.

2cy+:

• Uniform plumage lacking any moult contrasts.
• Whole wing and tail in better condition than 1cy, with denser structure and better gloss.
• CC longer and denser, with colder, chestnut or rufous fringe, similar to ad-type GC.
• Ad PC are generally denser, broader and blunter than juv feathers. Black colour is colder and glossier, and fringes to outer PC are frostier white than in juv, sometimes corresponding with white colour on outer vanes of inner PP, though often more warm-buffish when fresh. Fringes to inner PC warmer brown, more similar to 1cy.
• Tips of RR slightly blunter and broader, with wider white fringes, generally fresh until October.
• Iris rather reddish-brown.