Black-headed Gull Chroicocephalus ridibundus

(last update: 3-04-2011)

Below: First-calendar year Black-headed Gull, October 23, 2010, Buitenhoflaan, Leiderdorp, The Netherlands (52.167N, 4.528E). Photo: Maarten van Kleinwee.

First-calendar year Black-headed Gull in first-winter (formative) plumage. This individual has completed its post-juvenile moult in which all feathers are replaced except those on the wings and in the tail. The body and head are now completely white, leaving a head pattern similar to adults (ear spot and faint bars from ear to ear and eye to eye across the head). The legs are orange and the bill is orange with a white tip.

On this individual, all of the greater coverts as well as the inner median coverts have been replace by gray, second-generation feathers.