Mediterranean Gull (L. melanocephalus)
Mediterranean Gull 2cy HE68 January & December 2010, Le Portel / Boulogne-sur-Mer, NW France. Picture: Jean-Michel Sauvage.
Ringing data: ringed as pullus on 31 May 2009 at Rétszilas, Fejér in Hungary (46.51'N 18.34'E). Distance: 1318 Km.
below: HE68 2cy December 08 2010, Le Portel / Boulogne-sur-Mer, NW France. Picture: Jean-Michel Sauvage.
From May to September, the first complete moult takes place, into so-called "second winter" plumage. The head pattern resembles the pattern in first winter birds, with a blackish mask behind the eye. The mantle, scapulars, tertials and all wing-coverts are replaced with plain pearl-grey feathers. The secondaries are as in adult birds, pale grey with a white tip. The second generation primaries are much paler than the first juvenile primaries, but still not nearly all-white as in adults. After finishing this complete moult a 2cy Mediterranean Gull in autumn has a diagnostic wing-tip pattern with a variable amount of black on P5-P10. P5 has only a small black sub-terminal spot, becoming gradually larger on the outer primaries as the black patch "eats up" the white along the edge of the outer-web, most prominent on P9-P10. In some birds, the outer greater primary coverts and rarely the alula coverts may show dark markings as well. The bill is orangey-red with a dark sub-terminal band. The legs are dull red or more obvious orangey-red. As with 2cy birds there is individual variation in this age group but it is less pronounced and mostly involves the amount of black in the outer primaries and the colour of the bill.
below: HE68 January 06 2010, Le Portel / Boulogne-sur-Mer, NW France. Picture: Jean-Michel Sauvage.
Bird from Hungary, carrying a very happy "Nils Holgerson" all the way to Le Portel.
The partial autumn moult (post-juvenile moult into so-called "first winter" plumage) takes place right from the moment the juveniles leave the colony (usually mid July) and is finished by late September. It's a partial moult of the head and body feathers. The head and under-parts become almost completely white, the head with a clear dark mask of variable size behind the eye extending over the nape. The eye-crescents are white. The second generation mantle and scapulars are plain grey. The edges of the rich brown wing-coverts bleach to pale brown and the white fringes are all but worn away. Only a limited number of lower lesser coverts and median coverts are included in the post-juvenile moult. In this individual the upper tertials and innermost greater coverts have been replaced by plain grey second generation feathers. All juvenile feathers show some wear by October, contrasting with the recently moulted second generation feathers. The base of the bill starts to turn paler and the legs remain dark, but on some birds turn slightly paler.
Note that the comments on moult are based on observations of juveniles from and in Western Europe in early autumn. More easterly fledged Mediterranean Gulls may postpone their moult to first winter until later in the autumn and very fresh looking juveniles may be encountered well into October.