Ficedula albicollis - Spring - Ringers Digiguide

AGE – BEST CRITERIA:

Males are usually readily aged but, in females, individual differences in wear and moult makes ageing problematic at times. Moult contrasts are present in the GC (and often in inner SS) in both age classes, and should be examined carefully together with the PC.

2cy:

Outermost GC (often the 2-4 outermost) are unmoulted juvenile, being more worn, less dense and paler brown than adult post-breeding ones. The white wedge shaped tips seen in inner juvenile GC are less obvious or even absent on the outer GC, and since the outer ones are the only juvenile GC still left in spring, the character is less straight forward to use by then.
The juvenile PC are usually less dense and more worn than in adult, but in females the differences are not always obvious.
PP and SS still juvenile (though one or more inner SS are often moulted pre-breeding), showing more wear and bleach in the tips than adult ones.
RR are usually included in the pre-breeding moult and, hence, gives no clue to the birds age.

3cy+:

Outermost GC (often the 2-4 outermost) are unmoulted post-breeding, being less worn, more dense and darker brown (esp. in males) than juvenile ones.
The post-juvenile PC are usually more dense and less worn than in 2cy but, in females, differences are not always obvious.
PP and SS still post-breeding (though one or more inner SS are often moulted pre-breeding) and are generally in better condition than juvenile ones.

2cy May (male). Like in all birds (regarless of age) inner GC are fresh pre-breeding, dense and show typical black-and-white pattern. Relevant for ageing, outer GC1-3 are still juvenile, reckognized by being worn and pale brownish. Note that the white wedge shaped tips seen in juvenile GC during the autumn are less obvious (or even absent, like here) on the outer GC, and since these are the only juvenile GC still left in spring, the character is less straight forward to use by then. [CV04414]

2cy May (male), showing variation with moulted pre-breeding GC3-10 contrasting to juvenile remaining GC1-2. It should be born in mind that some individuals (not shown here) may show a sudden change in colour of the GC, although the feathers are still of the same generation. Such pattern may easily be misread as a moult contrast. [CV04413]

2cy May (female). Females are generally harder to age since it's more difficult to judge wether the outer unmoulded GC are juvenile or post-breeding than in males. Here, outer GC1-2 are juvenile, more worn, less dense and often slightly narrower compared to the post-breeding versions that an 3cy+ would have shown (see below). [CS70044]

2cy May (female), showing variation with GC1-2 still juvenile. Some individuals are difficult indeed and it is important to check all relevant characters (still, a few are best left without age). [CP45903]

3cy+ April (male). Unmoulted outer GC1-4 are post-breeding and, compared to juvenile feathers, are less worn, denser, variably blackish-brown and slightly broader. [CX52485]

3cy+ April (male). Another adult male showing post-breeding outer GC1-3. [CN93264]

3cy+ May (female). Outer GC1-3 are post-breeding, less worn, denser and slightly broader than the still juvenile GC seen in 2cy bird. [CX54630]

3cy+ May (female), showing variation with post-breeding GC1-3. [CN93292]

2cy May (male). Juvenile PC are usually less dense, faded pale brown and clearly worn, but more well kept birds are not always easy to separate from worn adult. [CV04414]

2cy April (male), showing variation. [CV02842]

2cy May (female). Juvenile PC are usually less dense, faded pale brown and clearly worn, but more well kept birds are not always easy to separate from adult. [CS70044]

2cy May (female), showing variation. [CP45036]

3cy+ April (male). Adult post-breeding PC are generally slightly more dense, darker and in better condition than juvenile, but differences are not always obvious.[CX52485]

3cy+ May (female), showing variation. [CX54630]

2cy May (male). In contrast to hypoleuca, most albicollis include the whole tail in the pre-breeding moult. That means that the RR seldom gives any clue regarding the age of the bird. [CV04413]

2cy May (female), showing slight contrasts in the tail. However, the worn feathers does not appear to be juvenile, and perhaps these contrasts are best explained by differentiated periods of pre-breeding moult during the winter. [CP45036]

3cy+ April (male). Uniformly post-breeding RR. [CN93264]

3cy+ May (female), showing variation. [CN93292]

2cy May (male). More or less all individuals (regardless of age) include all three TT in the pre-breeding moult, which makes them less useful for ageing. Many birds, like this one, also include one (or sometimes more) SS. [CN94679]

2cy May (female). According to Cramp et al. (1993) TT are included in the pre-breeding moult (like in hypoleuca). However, at Ottenby we regularly handle females with TT that was not moulted during the winter (obviously older and more worn than inner pre-breeding GC). Any existence of sexual differences in the extent of the moult remains to be proven. [CS70044]

Ficedula albicollis - spring