A winter loon with some breeding plumages? China (1 Viewer)

[xuky.summer]

Yesterday we took a boat on the Yellow Sea for a day and saw forty to fifty red-throated loons, but they were all very alert and started taking off from 150 meters above. After returning, I found this loon(?) is a bit special. The whole neck and head look black. Is this a remnant breeding feather?
The photo is very blurry, thank you

 

[Andrew Whitehouse]

It looks a juvenile Red-throated, which is much darker on the head and throat than an adult.

 

[Andy Adcock]

Red-breasted Merganser isn't it?

 

[tconzemi]

Red-breasted Merganser isn't it?

not with this foot projection

 

[CARERY]

Agree with Andrew

 

[Nutcracker]

RTDiver for me too

 

[THE_FERN]

Red-breasted Merganser isn't it?

Surely wing shape is wrong and we see no evidence of the white flash on the secondaries