Larus cachinnans adult, June 28 2012, Baku landfill, Azerbaijan. Picture: Chris Gibbins.
Large mirror on P10.
Speckling category: >75%. Colour of iris: dark.
Red gape and orbital ring. Yellowish legs.
Measurement of bill dimension from picture: 2,92 = very long and slim, with little/no visible gonydeal angle (L:D ratio >2.8) = trait score 0.