Another new one for my North Dakota bird photo collection.
Male (Drake) Hooded Merganser (Lophodytes cucullatus)
Raised Crest, evidently (cornell).
He makes a distinct funny/odd sound (enature).
His most distinguishing feature is his crest, or “hood.” At rest or in flight, this hood appears as little more than a white line behind the eye, but when the drake is alert on the water, the fully-raised crest reveals an elaborate hood of white on an otherwise black head.
So in other words, he can look quite different on water depending on how he holds his head.