Mediterranean Gull 2cy, February 2003, Le Portel /Boulogne-sur-Mer, France (50.42N,1.34E). 

Three different birds from two days in early February at Le Portel to illustrate the slight variation in “first-winter” plumage in mid-winter. Compare these three to the 1cy birds in September. In the February birds the post-juvenile moult has finished months ago and what you see is the result of the individual variation in the amount of moult and wear. By February the old juvenile feathers of these young birds look much more worn than in adults and sub-adults who also have only a partial moult in autumn.

This post-juvenile moult is a partial moult into so-called "first winter" plumage that starts in July and will be finished by late September. This moult includes most of the head and body feathers. The head and under-parts become almost completely white, with a dark mask of variable size and intensity behind the eye extending as very narrow streaks over the nape. The eye-crescents are white and the dark smudge in front of the eye contrasts more than in full juvenile plumage. The second generation wing-coverts, mantle and scapular feathers are plain pale grey. The rich brown centres of the juvenile wing-covert centres bleach to a foxy brown and the white fringes quickly wear away. In most birds at least some wing-coverts are included in the post-juvenile moult. The extent of this covert moult is variable, as you can see below. The base of the bill starts to turn paler and the legs turn slightly paler as well.

Mediterranean Gull 3JW2 2cy February 06 2003, Le Portel /Boulogne-sur-Mer, France (50.42N,1.34E). 

This individual was ringed as a pullus in Belgium on May 26 2002, Green left 3JW2.

In this individual the innermost two greater and median coverts have been replaced by plain grey second generation feathers. One central median covert and most of the inner lower lesser coverts have been moulted to second generation as well. All tertials are retained juvenile feathers and show extensive wear by February, contrasting strongly with grey second generation scapulars. The base of the bill has turned somewhat paler, the legs have remained dark, but on some birds these are distinctly paler.

Mediterranean Gull 14W 2cy February 06-07 2003, Le Portel /Boulogne-sur-Mer, France (50.42N,1.34E). Two pictures. 

This individual was ringed as a pullus in Belgium on June 4 2002, Green left 14W.

In the left wing of this individual one tertial, two inner greater coverts, three of the median one lower lesser covert and one lesser covert have been replaced for plain grey second generation feathers. The right wing is slightly different in that only the innermost greater covert seems to have been moulted. All juvenile feathers show pronounced wear by February. Because of the very strong markings in the juvenile wing coverts there is still a strong contrast with the second generation feathers. The base of the bill is much paler on this bird than on 3JW2 with a pinkish hue and a dark tip. As with later age-groups the black on the bill is always more extensive on the lower mandible. The legs remain as dark as in autumn.

Mediterranean Gull 2cy February 07 2003, Le Portel /Boulogne-sur-Mer, France (50.42N,1.34E). 

In the preceding autumn this individual has moulted a lot more coverts than the previous two birds. Its moulted two tertials, two inner greater coverts, and most of the inner median and lesser coverts have been replaced by plain grey second generation feathers. The lesser coverts and retained juvenile median coverts are bleached and worn resulting in a less contrasting plumage when compared to Green left 14W. The base of the bill has turned pale greyish but the bill still looks mostly dark. In this bird the legs have remained very dark.