Primary pattern variation in Dutch Herring Gull Green YBKC in the years 2015 to 2018.
Green YBKC was ringed in the gull colony of IJmuiden Forteiland, the Netherlands as an adult in May 2013. All images were taken there as well.
Note the differences in:
- The shape of the mirror on P9
- The differences of the mirror on P9 between each wing
- The black mark on the outer web on P4
- The shape of the tongue on the underside of P10 in the left wing
- The presence/absence of pseudo-mirrors on the underside of P10 in the left wing
See the following images (click for a larger view):
29 June 2015:
18 April 2016:
24 April 2017:
30 April 2018: