European Herring Gull with an unusual dark eye on both sides

This European Herring Gull with very dark eyes was photographed December 6, 2013 on Aarhus Harbour. Several times I have noted an adult Herring Gull with a dark eye and subsequently noted the other eye was light, but in this individual both eyes were unusual dark and thus worth documenting.

While taking the pictures I came to think of the two blog posts about adult Vega Gull which were published by Chris Gibbins here and here, but besides eye color it was a rather ordinary Herring Gull.

Note the yellowish orbital ring.