I've sketched this adult Caspian Gulls (Lesser Black-backed Gull too) in my district on the Vistula river.
By the way i read some colour rings of Caspians - but only one of them is not from Poland - from Germany.

During last few days I had few records of Black-headed Gulls and many of Caspian Gulls.
This one BHG watched on the Zemborzyckie Reservoir should be from Netherlands.

Croatian gull observed in breeding colony.

 Hungarian BHG in Rokitno rubbish dump.

Dunlin watched yesterday on the Vistula River - rare wader in this time of year.