Albert de Jong
Larus cachinnans adult, September 2010, Dumpiai dump - Klaipeda, Lithuania. Picture: Chris Gibbins.
P7/P9, with P8 growing; very small moult gap for Caspian Gull. Almost thayeri-pattern on P10. Simultaneous moult in outer secondaries (common moult strategy). A large and very aggressive (presumably male) bird. It was calling very regularly and seemed to dominate all other gulls present.