Phylloscopus collybita - Autumn

AGE – BEST CRITERIA:

In 1cy, moult contrasts are generally present in GC (but may be difficult to detect, esp. if only GC10 is moulted) and often also in TT and tail. In 2cy+ the whole plumage is fresh and uniform, including wing and tail. Colour of iris is often helpful, but some adult seem to retain a rather cold brown-grey colour, difficult to separate from 1cy.

1cy:

Most individuals show 2-5 inner post-juvenile moulted GC with darker and more glossy centre and slightly more olive green egdes in contrast to the juvenile outer GC with somewhat buffish-green (or brownish-green) edges. Contrast between juvenile GC and post-juvenile MC not always easy to see.
Juvenile RR are somewhat narrower, show more pointed tips and are generally of less good quality (less dense, slightly paler brown and progressively more worn during autumn) than adult. Many 1cy include central R1 (or sometimes other RR) in the post-juvenile moult, contrasting to the still juvenile RR.
Many 1cy also include single (or all) TT in the post-juvenile moult, showing a slightly darker centre and brighter green edges than juvenile ones. A few 1cy also show one or two moulted inner SS.
Juvenlie PC are not always easy to separate from adult ones (esp. not during early autumn), but generally shows a looser and less dense texture, and get slightly more worn as autumn progresses.
Iris coloured in cold and dark grey.

2cy+:

Whole wing is fresh and uniform, lacking moult contrasts. GC, TT and PC are fresh with dark centre and olive green edges and has generally a denser texture than juveniles.
RR (as well as PP and SS) are uniformly fresh and dark, often showing broader feathers than in juvenile.
Iris is generally slightly warmer brown-grey (but some seem to remain slightly colder, difficult to tell from 1cy).

1cy October. The 4 outermost GC are juvenile, contrasting to the inner 6 post-juvenile GC showing darker and fresher centre and slightly more olive green edges. [SS6288]

1cy October (ssp. tristis). The 7 outermost GC are juvenile, contrasting to the inner 3 post-juvenile GC showing darker and fresher centre and slightly more olive green edges. [TJ4119]

2cy+ October. Whole wing uniform and fresh. GC rather broad with dark centre and fresh olive edges. [SS6411]

2cy+ September, showing variation. [SS3433]

1cy September. In this individual all RR are juvenile, somewhat more brownish, narrower with more pointed tips than in subsequent feather generations. [SS3099]

1cy September. R1-2 (in both sides) are post-juvenile, fresh, dark and broad, contrasting to the remaing juvenile RR. [SS6783]

2cy+ October. Typical adult tail, uniform, fresh, broad and dark post-breeding RR. [SS3006]

2cy+ September, showing variation. [SS3433]

1cy September. Uniformly juvenile TT, being slightly less dense and dark than in subsequent generations, and will become relatively more worn during autumn. [SS3099]

1cy September, showing moult contrast in the TT. The longest and shortest TT are juvenile, while the central one is post-juvenile, being slightly less worn, darker grey and with fresher green edges. [SS6023]

2cy+ October. Adult showing a complete set of post-breeding TT. [CV03246]

2cy+ October, showing variation. [SK1174]

1cy October. Juvenlie PC are not always easy to separate from adult ones (esp. not during early autumn), but generally shows a looser and less dense texture, and get slightly more worn as autumn progresses. [SS6196]

1cy October, showing variation in PC structure. [SS6523]

Phylloscopus collybita - autumn