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Hi,

Bird spotted on February 6th, in Bucharest (Herastrau Park). The question would be: graellsi/intermedius or heuglini? Any comments would be very much appreciated. Sorry for the quality of the pics.

Hi Cristian,
Nice find. In all respects a bird simlar to what we have in western Europe in 3cy.
There is no sign of any irregular replacements in the secondaries or primaries, and also the tail has much dark sub-terminal markings. Probably some heuglini moult secondaries and tail in the common sequence as we find it in western graellsii/intermedius; but in general this is probably a minority of heuglini. What I've seen from photo's on the web, heuglini commonly replaces tail-feathers and (randomly) secondaries, which would be visible in the spread wings now as more adult-like feathers.
Of course, intermedius can be rather 'advanced' in secondaries and especially tail as well, with an all white tail in 3cy winter birds. So, within the western taxa, your bird is illustrative for the most common pattern as can be found in typical graellsii, where birds have a grey 'saddle' (scapular region) and barred wing-coverts; except the feathers which have been replaced in the partial 2cy autumn moult (normally including few upper tertials, the innermost gc, most of the visible inner and central mc, and randomly some llc and lc).
BTW, not that I'm saying this is graellsii, in moult your bird may be similar to this taxon, but still many intermedius are pretty the same.

Thank you for your comprehensive comments, Mars.