Black-headed Gull Chroicocephalus ridibundus

(last update: 19-03-2014)

Black-headed Gull - 2cy May

This section deals with second-calendar year Black-headed Gulls in the month of May.

Introduction

In May, second-calendar year Black-headed Gulls will complete their partial moult into "first summer" plumage which has started in February (generally one month later than adults).

The plumage is characterized as follows:

• Mantle and scapular feathers are grey (as adult), while some brown, juvenile feathers can be retained.
• Head: dark blackish-brown hood  of variable extent. Majority (58%) have white-flecked dark hood, other variations are white head with sparse dark fleckings (24%), winter head pattern (11%) and full adult hood (7%).   
• Body as first-winter but hind neck and breast off-white or grey-washed in birds retaining winter head pattern.
• Bare parts: bill and legs: more orange, less flesh-coloured, prominent black tip to bill (exceptionally bill adult-looking: dark maroon-red)
• Wing and tail: moult has not taken place in the wing and tail feathers and therefore remain first-generation. Becoming very worn and brown areas fading.  Occasionally central tail feathers renewed (white).  Some lesser and medium coverts are moulted to second-generation, grey feathers (as adult).
• In flight, the dark carpal bar on the upper wing stands out, formed by the lesser- and medium coverts. The trailing edge is black, similar to the tail edge (the outer tail feathers of some individuals are completely white). The primaries have a white base, extending in a drop-shape to a black tip. The outer primaries usually have small white tips.

Most of the description follows: 
P.J. Grant: "Gulls, a guide to identification".
K.M.Olsen: “Gulls of Europe, Asia and North America”.