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third calendar year: July
By July, most 3cy LBBG show very slow continuation in their moult. Some replace mantle-feathers, scapulars and coverts. Most have adult-like bare parts and under-parts.
Moult of coverts
In most individuals, which may represent Dutch graellsii, at least the median coverts are actively moulted to adult-like grey feathers. Also, most birds start replacing tertials, lesser and greater coverts, from the end the month onwards. Throughout August and September, moult in the wing-coverts continues and by October most LBBG show a complete grey wing.
New coverts are often easily recognized; third generation feathers are typically uniformly grey, like in adult plumage.
The old retained second generation feathers show at least some brown markings in the centre and white fringes (although these fringes may be worn away and the exact pattern gets lost).
Tail-feather moult
As can be seen in the images of fresh third generation tails, there may be some variation in black and white division. Worn second generation rectrices are commonly seen at this age by July, i.e. a tail with a lot of black, at least with a broad black terminal tail-band.
During summer, the moult of tail feathers may be either absent or already be finished. Some fresh 3rd generation tail feathers still show isolated black spots, often on the outer webs of the tail-feathers R4 or R5.
Primary moult
Early July, some 3cy LBBG have already shed P4 and replaced P2 for a fresh adult-like primary. At the end of July some birds turn up with P5 replaced while P7 has been shed. The new third generation primaries are very adult-like grey with a white tip, totally different from the old abraded plain black-brown second generation primaries.
Still, the third generation primaries differ slightly from real adult primaries as the tips are marginally smaller, the mirror on P9 is often absent, the size of the mirror on P10 is smaller and P3 and P4 show extensive sub-terminal black markings (a complete sub-terminal band on p3 and p4 is common). Of course, the outer primaries are still old and completely third generation remiges are expected by November. Another indication for third generation primaries being different from adult ones comes with time; later on in the season the outer primaries quickly turn brown. Full adult birds show blackish P5-P10. With age the feathers look to be stronger, making them less vulnerable for bleaching and wear. Secondary moult starts later in the season.
Of course, the outer primaries are still old and the completion to third generation remiges are expected by November. Another indication for third generation primaries being different from adult ones comes with time; later on in the season the outer primaries quickly turn brown. Full adult birds show blackish P5-P10. With age the feathers look to be stronger, making them less vulnerable for bleaching and wear. Secondary moult starts later in the season.
Some remarks on primary moult.
Normally, the partial spring moult in graellsii and intermedius LBBG doesn't include the remiges. For a detailed description of this partial spring moult, see the May section. Again in July (as we saw in May and June), 3cy LBBG were encountered showing arrested moult, probably from last winter, prior to northbound migration. A full page is dedicated to discus these odd LBBG (see the page 'discusfus').
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