Chroicocephalus ridibundus - Black-headed Gull
It was ringed by Vogelwarte Hiddensee, Germany as 1st CY on July 16, 2003 near the Gülper See, Havelland, Brandenburg (52°45'N, 012°16'E). I saw it regularly between November 8, 2009 and March 6, 2010. After being absent during the spring and summer, I saw it again on December 5, 2010.