Black-headed Gull Chroicocephalus ridibundus

(last update: 3-04-2011)

Tim Audenaert
Maarten van Kleinwee


BHG 1cy May
BHG 1cy June
BHG 1cy July
BHG 1cy August
BHG 1cy September
BHG 1cy October
BHG 1cy November
BHG 1cy December

BHG 2cy January
BHG 2cy Febuary
BHG 2cy March
BHG 2cy April
BHG 2cy May
BHG 2cy June
BHG 2cy July
BHG 2cy August
BHG 2cy September
BHG 2cy October
BHG 2cy November
BHG 2cy December

BHG adult January
BHG adult Febuary
BHG adult March
BHG adult April
BHG adult May
BHG adult June
BHG adult July
BHG adult August
BHG adult September
BHG adult October
BHG adult November
BHG adult December

Below: Black-headed Gull, December 24, 2002, Amsterdam, The Netherlands.

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

This individual displays an unusual advanced moult, in which the majority of the wing coverts and all of the tertials have been replaced by gray, second-generation feathers. Aging this individual is done based on the orange legs, orange bill with black tip, first-generation primaries and dark tail band (not visible in this image).