Albert de Jong
Larus cachinnans 2CY XHEC April 07 2014, Medemblik, the Netherlands. Picture: Fred Visscher.
Data pending, probably ringed as pullus in Oberspreewald-Lausitz, Brandenburg, Germany (51°42'00"N 014°06'00"E) in 2013. This is 100 km SE of Berlin and Lausitz holds a mixed colony in the lake. At this location ringing takes place in colonies of mixed species, with Herring, Caspian and Yellow-legged Gull, so identification is not always straight forward. The possibility that juveniles are not a pure bird is therefore not unlikely.
However, this green XHEC seems to be a nice cachinnans. Probably male.