Black-headed Gull- Kokmeeuw (L. ridibundus)

(last update: 18-10-2005)

Photo 7517: Black-headed Gull L. ridibundus 1cy, December 24 2002, Amsterdam, the Netherlands.

The partial autumn moult (post-juvenile moult into so-called "first winter") started right from the moment the nests was abandoned last summer and ended last September. In this bird, the partial moult included the head and under-parts and many of the wing-coverts. The buff-brown coloration on the head and in the lower hind-neck has been replaced: the head is most white now with a typical black spot on the rear ear-coverts and a dark patch around the eye, in this bird ill-defined and slightly extending over the crown. The mantle and scapulars have been replaced for second generation feathers which are all grey. In the lowest row of scapulars, two rear feathers are still missing. The upper tertials have been replaced for second generation feathers. The brown centred tertials are now all grey. The inner greater coverts were replaced as well and appear plain grey, in line with the upper tertials. As can be seen in the images, from the fourth greater covert outwards, the centres are slightly brown hued and the fringes worn, contrasting with the very fresh inner three greater coverts. Half of the median coverts (the inner half of the row) and some of the lower lesser coverts have been replaced to second generation plain grey feathers, contrasting with the still juvenile outer wing-coverts. As can be seen, the fringes of these juvenile outer wing-coverts are brown centred, bleached and worn at the fringes. Note the dark tail-band, typical for 1cy birds.

Next moult will take place in early spring (from February to April: moult into so-called "first summer" plumage) and again will include the body and head. The hood will be more or less developed, although often with white flecking. A few individuals may include the central tail-feathers in this partial moult.