possible Lesser Black-backed Gull graellsii x Herring Gull argenteus KB adult, May 28 2013, Katwijk, the Netherlands.
Picture: Jeroen Nagtegaal & ringing team Roland-Jan Buijs.
Metal NLA 5424660 and tibia yb KB. Trapped on the nest, incubating 1 egg. Obvious Lesser Black-backed Gull characters like red gape, red orbital ring, yellowish legs. Clean yellow iris.
Full black band on P5, small spot on P4. Mirror on P9 and P10, P10 mirror merged with white tip. Kodak grey tone is 8, which is too dark for Herring Gull and pale for Lesser Black-backed Gull.