A very interesting and unusual winter sight of a juvenile Mediterranean Gull
Picture taken on the 7th of December 2009 at 11:43 PM near Durankulak Lake, Northern Bulgarian Black Sea coast.
The primaries and secondaries of the bird indicate a 1st winter (1cy) but the head is similar to breeding adult and its bill is also full on. It could be also a 2cy in spring/early summer bird with some form of suspended moult having developed an adult type hood.
But, considering that the picture was taken in December it would be a unique bird in a very unusual plumage for the winter time. Firstly because this bird would then have juvenile primaries that are at least 18 months old without excessive wear and without any visible moult. The same goes for the lesser coverts; there is still a strong brownish hue to the part that is visible in the picture.
A head and bill like this on a 2cy bird is uncommon but not unheard of in late May/June but it should be in moult from July/August at the latest. Combining those two unlikely characters in December seems very unlikely.
If it is a 1cy bird it seems to have moulted into a full adulttype head. Those must be some strong hormones he's on!
So, an extraordinary bird with 1st wing flight feathers & adult like hood...A very odd bird for December?