Nice flight shot of what appears to be heuglini, on primary pattern and heavy structure.
Note what looks like a growing inner primary (p1) in the left wing, just visible white tip, repeated in the right wing and missing middle secondaries, not yet fully grown. Is it the start of a new primary moult, which would be a strange strategy for heuglini, which is in the end of the complete p-moult with fresh primaries. The primary moult starts at the breeding ground with a few inners, then suspended/arrested prior to migration - to be finished on the wintergrounds.
See difference between suspended and arrested moult. From Gull Research Organisation Website.
"Arrested moult or suspended moult?
In discussions about arrested moult, suspended moult is included as well. Strictly, the difference between arrested and suspended moult lies in the continuation:
Suspended Moult: A bird starts moulting the flight feathers in the ordinary way (from P1 outwards). At a certain point, the moult stops (is arrested, e.g. when migration starts). After arrival, the bird catches up moulting the rest of the flight feathers, which can be recognized as fresher.
Arrested Moult: A bird starts moulting the flight feathers in the ordinary way. At a certain point, the moult stops. After arrival, the bird starts moulting P1 again, thus doesn't continue moulting the rest of the flight feathers.
In some cases moult continuation is combined and two moult waves start: one wave at P1 and one wave at the place where moult was arrested, prior to migration. This is visible as two gaps in the wing (beware of secondary moult in the outer secondaries (S1, S2, S3)."
Also the third heuglini here - from Oman by Dick Newell:
http://www.magikbirds.com/image.asp?title_id=610&search=0&show_thumbnails=False
JanJ
