www.gull-research.org

Several such extreme individuals are seen at the moment in Denmark and at least in southern Sweden. They appear to more frequent right now than ever before.

http://gulldk.blogspot.com/2011/12/herr ... -with.html

Does any have references for the explanation for such extreme colours to occur even across several age classes? Have they all been eating food high in organic pigment such as Carotenoids???

Cheers

Kent

"Have they all been eating the same food with high concentration of Carotenoids? "

I guess so yes. Do you have a shrimp factory in the neighbourhood?

It seems to be not a local phenomena in Aarhus. In Baltic Germany (Schleswig-Holstein near Danish border) the same too.
http://f3.webmart.de/f.cfm?id=1231426&t ... threadview

Rødvig Havn 8.12.2011 Denmark

Was there any local mess (accident) in Denmark? I am afraid it.

Thank for your comments and links to similar extreme coloured argentatus which by now have been reported from all around Denmark and least southern and eastern Sweden, northern Poland, Baltic Germany, however, individuals now are reported along their south-western migration route into Western Europe including the Netherlands.

It seems as if these gulls are found most abundant along the coastline of the Baltic Sea and the areas where it drains into such as Kattegat by the way of Øresund, the Great Belt and the Little Belt. Thus the source of origin should most likely be within the eastern part of this area.

On the 29th January I found a extreme coloured Herring Gull in Steinhude, Lower Saxony (Germany).