Mystery duck/scoter?! Dec 5th, near Dover, Kent UK (1 Viewer)

[xaviertaylor]

Hello chaps - The photos aren't great... but this duck/scoter/thing is baffling me! Head and beak shape reminiscent of Eider... but seemingly quite a prominent white breast. Was diving a lot. Photos taken today - not far from Dover in Kent. Any ideas?
Apart from the pale breast, in the poor light it looked all dark colour... but several of the photos I've taken show a possible paler marking on the top of the ahead above the eye. Not sure if that's an effect of the light though.

 

[Butty]

All fine for common eider - inc. head/bill-shape.

 

[Bismarck Honeyeater]

Eider is correct

 

[Joern Lehmhus]

Yes, Eider male - but 1st winter / not in full breeding plumage , closer to these:

https://cdn.download.ams.birds.cornell.edu/api/v1/asset/24916691/640

https://www.birdsoutsidemywindow.org/wp-content/uploads/2022/09/COEI_ecplise_blueblue_wiki.jpg

https://c8.alamy.com/comp/2BKA2NK/common-eider-duck-somateria-mollissima-males-moulting-from-eclipse-plumage-northumberland-uk-2BKA2NK.jpg

 

[xaviertaylor]

Thanks so much everyone - appreciate the explanation too!