Gull resembling Ring-billed Gull from Poland          

On 4th November 2003 at Jeziorsko reservoir (central Poland), I photographed this adult gull standing in a flock of Common, Caspian and Black-headed Gulls.
The bird was similar to Common Gull but was: slighty larger with longer and yellow legs, yellow iris, yellow and thick bill with black band, paler mantle. However jizz resembling rather Common Gull, white terial crescent was thick and thin black bill band.
Till now in Poland we have only 5 accepted records of  Ring-billed Gull so I will be very grateful for opinion and help with the identification.

Any comments are welcome.

Marcin Faber
Poland
marfaber@poczta.onet.pl
www.czaplon.most.org.pl