Lesser Black-backed Gull NT0 6cy, March 18 2002, Missouriweg, Maasvlakte, the Netherlands (51.59N,04.02E). 

An adult female ringed, left orange NT0 in white code. This bird was ringed as pullus July 11 1997, now in its 6cy. Note the rather parallel bill lacking a clear gonydeal angle. The primary tips are relatively small, though still very fresh and this bird has p10 well beyond p9. There are no moult gaps in any feather tract, but the inner median and greater coverts were probably moulted a while ago and now show a brown hue and wear in the fringes.

(below) Lesser Black-backed Gull NT0 6cy, May 13 2002, Missouriweg, Maasvlakte, the Netherlands (51.59N,04.02E).