second calendar year: October
By October, all LBBG have left the colonies at the Maasvlakte (the Netherlands). In the pictures you can see what variation can be expected in 2cy LBBG by October. The variation seems large, but overall, 2cy LBBG may be classified in the following categories: Category I Those birds with second generation-like third generation feathers (click thumbnail #3). Second generation feathers often show characteristic anchor pattern, barring or deep notches in the fringe. Some 2cy birds replace these feathers in summer for more or less the same kind of feathers. Often the medians show barring or club patterns while the greater coverts have dense spaghetti like barring. This group of LBBG don't have grey feathers in the scapular region and in general there are no "adult-like" features. So far, we were not able to determine this type to geographical locations and probably such type of LBBG may turn up in both graellsii and intermedius (although there is a tendency to allocate them to graellsii). Several birds of this group originated from U.K. colonies, from Belgium and the bird in picture 1, ringed AH53 from northern Germany may be classified as "second generation-like third generation" as well. When birds of this type are heavily built, strong and robust in appearance, they may be mistaken for Yellow-legged Gulls (L. michahellis) in 2cy plumage, especially the ones without grey scapulars (but this is a rare case in October). Category II In October, 2cy LBBG move into the 'steady winter months' where moult is more or less suspended until early spring. However, some LBBG moult throughout the winter, at a lower pace. Others may appear very advanced and may show a 3cy spring plumage already by October, including the all grey adult-like scapular region and some grey median coverts. The lesser and greater coverts are still barred or with a club pattern. There are a few examples in the pictures, and the LBBG in picture 2, ringed in the Netherlands can be classified to this group. This category of LBBG is as hard to allocate geographically as the other group. Category III And finally, there is a third -intermediate- group: those 2cy LBBG with grey scapulars combined by strongly patterned wing-coverts. As can be seen in the spring section of 3cy, this may be the plumage in which they return next year. Partial moult in 2cy intermedius & graellsii Although an undefined number of
-predominantly intermedius- LBBG arrive from the wintering
grounds with moulted wing-coverts and scapulars, the general idea is that,
in line with large white-headed gulls of NW Europe, Lesser Black-backed
Gulls start moulted from late April onwards: the complete moult. This
complete moult includes all the wing-coverts, body-feathers, rectrices and
of course the remiges. By September, the replacement of the last lesser
coverts, inner secondaries and outer rectrices is finished, together with
last to outer primaries.
Arrested primary moult in autumn Arrested or, much better, suspended moult
in the primaries is a rare phenomenon in 2cy LBBG graellsii and intermedius.
The common moult stage in 2cy LBBG is P9 fully grown and P10 slightly
shorter than P9, often at the length of P7 or P8 by the first week of
October. Some birds are a little behind in moult with P8 the longest
primary. |
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2cy LBBG: 'Dutch intergrade' |
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2cy LBBG GJ84559 October 08 2001, Westkapelle, the Netherlands. Picture Pim Wolf. | ||
2cy LBBG E532E October 05 2002, Dannes - Le Portel, NW France. A 2cy graellsii ringed at Maasvlakte, the Netherlands as pullus on July 01 2001. | ||
2cy LBBG C95E October 01 2004, Amsterdam, the Netherlands. Ringed at Maasvlakte, the Netherlands as pullus. | ||
2cy LBBG 5.361.744 October 22 2001, Westkapelle, the Netherlands. Ringed in the Netherlands. | ||
2cy LBBG 5.364.530 October 21 2004, Westkapelle, the Netherlands. Picture Pim Wolf. | ||
2cy LBBG 5.412.032 October 01 2004, Westkapelle, the Netherlands. Picture Pim Wolf. | ||
2cy LBBG L-102569 October 07 2004, Westkapelle, the Netherlands. Picture Pim Wolf. | ||
2cy LBBG L-102780 October 21 2004, Westkapelle, the Netherlands. Picture Pim Wolf. | ||
2cy LBBG L-106398 October 19 2004, Westkapelle, the Netherlands. Ringed in Belgium. | ||
2cy LBBG: intermedius |
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2cy LBBG AH53 October 13 2001, Westkapelle, the Netherlands. A 2cy ringed AH53 on Helgoland, Germany. | ||
2cy LBBG JU30 October 19 2002, Westkapelle, the Netherlands. A 2cy intermedius from southern Norway. | ||
2cy LBBG 4236519 October 16 2004, Westkapelle, the Netherlands. | ||
Category I Nine images of 2cy LBBG, October 13 2001, Westkapelle, the Netherlands. Nine examples of rather brown 2cy LBBG, lacking the grey scapular region and grey medians. |
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Category II Nine images of 2 cy LBBG, October 14 2001, Westkapelle, the Netherlands. Birds with a grey saddle and many grey third generation coverts. |
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Category III Seven images of 2 cy LBBG, October 22 2001, Westkapelle, the Netherlands. 2cy LBBG with (a few) grey scapulars but lacking the grey median covert bar. |
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PARTIAL MOULT IN 2CY Photo 3: 2cy LBBG, October 05 2002, Dannes - Le Portel, NW France. Third generation rectrices in autumn. |
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ARRESTED MOULT IN 2CY Photo 5576: 2cy LBBG, October 05 2002, Boulogne-sur-Mer, NW France. The outer primaries are still juvenile: moult will be suspended at P8. |
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