Gulls from the Wytyckie Lake waiting for the end of winter. Here - Zemborzycki Reservoir, 50 km from colony.
Yellow-legged Gull with adult Caspians.
and short video: https://www.youtube.com/watch?v=ARATY_i02Lw
Good numbers of Caspian Gulls and few Herrings were gathering on the sand (Vistula River); I made this sketch of few of them.