Sylvia curruca - spring

Lesser Whitethroat


Individual differences in wear and moult makes ageing problematic at times. Moult contrasts are often present in alula, tail, TT and inner SS in both age classes, and should be examined carefully. The pre-breeding moult in the GC is restricted  – innermost GC may be replaced, but most individuals does not include any GC at all.


  • If present, juvenile GC (commonly 0-3 juvenile GC kept unmoulted) are detected by being slightly darker brown, more worn and frayed. If all GC are moulted, there is a (less easily detected) contrast to the still juvenile PC.
  • The juvenile PC are worn (often considerably) and frayed and often appear darker brownish compared to adult ones.
  • If juvenile alula feathers are still present, they are brownish worn, often in contrast to post-juvenile or pre-breeding ones showing less worn greyish tips/edges and a more glossy dark/black centre.
  • Tips of PP are generally more more worn and bleached, often appearing more brownish.
  • Any juvenile RR still left are generally considerably worn, narrower and more pointed than post-juvenile or pre-breeding RR. Juvenile R6 shows pale markings in off-white or dirt-white and R5 lacks white at tip.
  • Iris is not useful during spring as it has developed adult colour/pattern.
  • PC often in slightly better condition than in 2cy, on average less worn and often a bit paler with slightly greyish edges.
  • Alula feathers (post-breeding and/or pre-breeding) show glossy dark centra with less worn greyish tips/edges. No juvenile alula present.
  • Tips of PP generally in slightly better condition, being darker and less worn and bleached.
  • RR are often mixed post-breeding and pre-breeding generations, differing in wear, but are broader and in much better condition than juvenile ones. R6 shows pale markings in pure white and R5 have pure white tip. No juvenile RR present. 
  • Iris is not useful during spring.

2cy April. The 5 outermost GC are unmoulted juvenile, darker brown and more worn compared to the slightly paler adjecent post-juvenile GC which are in better condition. [CP44782]

2cy April. All 10 GC are post-juvenile, and show a slight contrast to the juvenile brownish PC. [CP44974]

3cy+ April. Moderately worn adult wing showing lack of moult contrasts in GC/PC. [CN94338]

3cy+ April. Variation (slightly browner) of adult wing. [CV02639]

2cy May. Inner (small) AL is post-juvenile, showing a darker centre and paler grey tip in contrast to the two worn juvenile longer AL feathers. [CS01849]

2cy April. All three AL feathers are non-juvenile. Innermost appears to be fresh pre-breeding while the longer two may be post-juvenile, but separation of these generations are generally not easy. [CP44782]

3cy+ May. Adult AL feathers show glossy blackish centre and greish edges. [K3H6686]

3cy+ May, showing variation in AL pattern. Note that adult may show two generations of AL (post-breeding and pre-breeding). [CN93493]

2cy April. Juvenile PC are browish worn (often considerably so) and frayed. The edges often appear darker brown than in adult. [CP44974]

2cy April, showing variation in PC pattern and wear. [CS01719]

3cy+ May. PC are often in slightly better condition than in 2cy, on average less worn and often a bit paler with slightly greyish edges. [CN94338]

3cy+ April, showing variation in PC pattern. [CP44885]

2cy May. All three TT are of typical juvenile quality - worn, bleached and frayed. Note that this bird shows a moulted (probably post-juvenile) S6, which both age classes often do. [CS02238]

2cy May. Another individual showing some variation. No juvenile T present, and therefore of less relevance for the ageing. At least the longest T (as well as S6) is pre-breeding, and the two shorter ones are (likely) pre-breeding or (less likely) post-breeding. [CP45963]

3cy+ May showing a complete set of post-breeding TT. [CP44885]

3cy+ May showing variation in adult TT, longest one being pre-breeding while the shorter two are post-breeding. [CN94338]

2cy May. Juvenile PP are of less good feather quality (less dense, less gloss and with a brownish ground colour) and will show a more progressive wear and bleaching in the tips during spring than adult ones. [CS01849]

2cy April showing variation in wear. [CP44974]

3cy+ May. Adult PP are generally in better condition (denser, darker, better gloss, less worn and bleached) than juvenile ones. [CP45647]

3cy+ May, showing variation. [CN93493]

2cy May showing juvenile (right R1-2), post-juvenile (most of the tail) and pre-breeding (left R1) rectrices with wear typical to the respective generation. Without presence of juvenile feathers the tail would not have helped the ageing. [CS01849]

2cy May, showing variation in tail pattern. The whole tail is pre-breeding except for left R1 which is likely post-juvenile and, hence, does not give any clue to the ageing (it is not possible to separate post-juvenile and post-breeding feather generations). [CS01990]

3cy+ April. Whole tail is fresh pre-breeding (not useful for ageing). [CV02639]

3cy+ May, showing a dominantly pre-breeding tail with post-breeding T1 (both right and left). [CP44885]

2cy May. Iris is not useful during spring as it has developed adult colour/pattern. [CS01990]

2cy April, showing variation in iris colour. Some individuals (of both age classes) have a more uniformly brown iris. [CV02776]

3c+ May. Iris is not useful during spring. [CN94338]

3cy+ April. Another individual showing some a more uniform warm brown iris. [CP44885]

More Sylvia curruca:
Ageing autumn

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