Herring Gull (Larus argentatus) with extra dark upperparts

This adult Herring Gull was seen in Aarhus Harbor on January 11, 2011. All characters besides the extra dark upperparts appear to fit within the variation of an argentatus even though a hybrid origin cannot de completely dismissed.

Birds from the northeastern most populations of argentatus can have darker upperparts than the more western birds that we normally have in Denmark.