Parus major - Spring - Ringers Digiguide

AGE – BEST CRITERIA:

Autumn criterias are still applicable, though the still juvenile feathers in 2cy are more affected to wear during the winter than adult. Moult contrast is always present in the wing of 2cy, in the vast majority between post-juvenile GC and juvenile PC (though not always easy to find). Adult birds show a uniform and freshly moulted plumage.

2cy:

Most birds included all GC in the post-juvenile moult. The more dense GC with rather bright blue-grey outer vanes shows a contrast to the less dense and less brightly coloured juvenile PC. This contrast may be easily detected, but quite a few birds are more difficult. Occasionally (c. 8% at Ottenby) 1-3 outermost GC may be unmoulted juvenile, and then show a more easily seen contrast to inner post-juvenile GC.
A moult contrast is often seen in the alula/CC, often with CC and the innermost alula moulted post-juvenile contrasting to outer two juvenile alula. Post-juvenile alula are more dense than juveniles ones, and the inner two feathers show the same bright blueish-grey colour as the post-juvenile LC, MC and GC, whereas juvenile ones are less dense and colourful. Longest alula is darker regardless of which generation is present, but difference in quality between juvenile and post-juvenile generation still detectable.
Most birds (c. 70% according to Jenni & Winkler 1994) moult all TT. Among the rest, the vast majority shows one (the longest) unmoulted juvenile T, while 2-3 retained juvenile TT are rather rare.
C. 90% (according to Jenni & Winkler 1994) moult all RR, and c. 2% moult none. Remaining birds show a contrast between post-juvenile and juvenile RR. The latter is recognized by being slightly more worn, often greyer (less blueish-grey), slightly more narrow and pointed at tip.
Iris is rather dark olive-grey.

3cy+:

Uniform plumage lacking any moult contrast.
PC denser and with a slightly brighter blue-grey gloss.
Iris usually slightly warmer greyish-brown.

2cy March. One of the rather few individuals showing a moult contrast in GC: Outermost GC1 is juvenile, more worn, less bright blue-grey outer vane and with a smaller pale tip, in contrast to inner post-juvenile ones. [2KR44241]

2cy March. All LC, MC, GC and CC are post-juvenile, in contrast to juvenile PC. [2KR44072]

3cy+ March. Whole wing post-breeding, with no contrast between GC and PC. [2KR44232]

3cy+ March, showing variation. [2KS80285]

2cy March. Note the juvenile PC, less dense and slightly less brightly coloured than post-juvenile GC and AL. [2KR44117]

2cy March, showing variation. [2KR44072]

3cy+ March. Adult PC are denser and generally shows a slightly brighter blue-grey gloss. Note the lack of contrast to GC. [2KR44232]

3cy+ March, showing variation. [2KS80287]

2cy March. The CC and AL are post-juvenile (denser with brighter blue-grey gloss) in contrast to the PC. Although not shown here, quite a few 2cy show moult contrast in AL. [2KS74615]

2cy March. The CC and AL are post-juvenile (denser with brighter blue-grey gloss) in contrast to the PC. [2KR44029]

3cy+ March. Uniformly post-breeding AL (as well as rest of wing). [2KS80285]

3cy+ April, showing variation. [2KR44232]

2cy March. Most 2cy show a uniform set of post-juvenile TT, but exeptions are not uncommon. This birds shows post-juvenile inner and central TT, in contrast to the outer (longest) that is unmoulted juvenile. [2KR44243]

2cy March. Another one showing the same moult pattern with post-juvenile inner and central TT, in contrast to a juvenile outer. [2KR44237]

3cy+ March. Uniform post-breeding TT. [2KR44232]

3cy+ March, showing variation. [2KS80285]

2cy April. Most 2cy (like this one) shows a uniform post-juvenile tail, inseparable from the adult post-breeding. Birds showing contrast between post-juvenile and juvenile RR is not rare however. The latter is recognized by being slightly more worn, often greyer (less blueish-grey), slightly more narrow and pointed at tip. See photo in autumn chapter. [2KR44072]

3cy+ April. Uniform post-breeding RR. [2KS80345]

Parus major - spring