The Glaucous Gull went missing just seconds before I arrived but still an interesting day at Lauwersoog. I spent several hours in the harbour trying to relocate the Glaucous, but we failed.
Instead an interesting pale-winged juvenile "large gull" allowed detailed study. From a distance it resembles a Glaucous/Iceland Gull but it is a shade too dark, actually Thayers Gull would fit better! But head-shape and tertail pattern indicates Herring Gull (maybe mixed with some foreign genes).
Below some more images of this interesting plumage;
A single Kittiwake was feeding between the hundreds of Black-headed Gulls
Actually I think this is my first Iceland at Lauwersoog, Martijn, thanks for calling!