Mystery Duck in MA, USA (1 Viewer)

[hannibalscannibal]

hello all! i'm new to this site so please stick with me here

this duck was sighted in Plymouth Harbor, Massachusetts around 5:30 PM on May 6th.

it had the distinct sloping head of a Scoter or Eider and was diving frequently very close to shore, but doesn't match the profile for any local species i'm familiar with
my first thought was Spectacled Eider due to the bold white circles around the eyes, but they don't live anywhere near Massachusetts! colors were very bold and defined so likely not a juvenile of any species

any insight is appreciated, image attached below is the best i got (taken through the lens of my binoculars to avoid disturbing the bird)

 

[aeshna5]

Male Long-tailed Duck. You can even see the long tail here which would exclude all the species you mentioned.

 

[hannibalscannibal]

Male Long-tailed Duck. You can even see the long tail here which would exclude all the species you mentioned.

it didn't actually have a long tail which is what threw me off, i think the "tail" in the image is a water distortion
thank you though!

 

[Microtus]

It's a male Long-tailed Duck in breeding plumage

 

[KC Foggin]

I'm going with Long-tailed Duck as well.