Than thank you BobbitWorm45, I must admit that I have seen Lesser Scaup only in captivity before. So I hope that you can write something more, so I can learn.
I know, the iriscent colour of the head is variable in diving Ducks. Bu while I have seen some Tufted Ducks with a green sheen to the...
The male seems a Lesser Scaup to me, please note:
-just visible peak at rear crown, not rounded (better visible in the thumbnail)
-violett, not green gloss to head
-head seems to small in relation to body for a Greater Scaup.
For the female/1cy I wait for others, so I can learn.