Mallard with a blue/grey bill (1 Viewer)

[Wildlifetastic]

New to the bird forum but a long time birder. Today I came across a fascinating Mallard. This Mallard had a bluish-grey bill; you can notice on the image that there is some faint yellow at the base of the bill. What I am wondering is if this a form of carotenoid issue or Leucism? or simply that this is a young mallard? Any information or further resources would be much appreciated.

 

[KC Foggin]

That is one beautiful close up image of this handsome Mallard.
Sorry, can't explain the difference in the bill color. I don't want to say it's a hybrid because all of this colors are normal.

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[Wildlifetastic]

That is one beautiful close up image of this handsome Mallard.
Sorry, can't explain the difference in the bill color. I don't want to say it's a hybrid because all of this colors are normal.

I'm just going to jump in here and wish you a warm welcome to you from those of us on staff here at BirdForum
We're glad you found us and please join in wherever you like

After scouring the internet I believe that it could be a) carotenoids issue or b) a hybrid with a Lesser Scaup. I am still trying to find a difinitive answeer to my question though. Haha

 

[Wildlifetastic]

Perhaps a better angle of his coloration might help solve the mystery.

 

[Joern Lehmhus]

This is a variant in mallard bill coloration, most likely lacking the carotenoids and therefore resulting in a bluegrey bill like in wigeon or pintail. There is no sign of hybridisation with another species; a mallard x scaup sp., though documented, looks quite different , much plainer and more uniform in body plumage.