Note the long bill, and how the line of the culmen continues as a straight line all the way to the back of the head, where there is a clear peak far beyond the eye. The neck is quite straight when alert and the lowest part is rested on the back. The last isn't that big of a deal, maybe, but the overall shape of the head and bill is quite striking.
The Buncombe swan has a medium-length bill, there is a somewhat "puffy" forehead (a rise where it meets the bill), and the head is somewhat rounded, such that is difficult to see where the highest point in the head is relative to the eye. You don't see the long straight line from the bill tip all the way to a distinct peak of the crown toward the nape, well behind the eye. The stretched-out neck looks medium length to me. Here is a good profile (second one) of the Buncombe bird:
On Fri, Feb 24, 2017 at 9:49 AM, <susan...> wrote:
> All, > > To this debate, I will add that molt in immature Tundras can be quite > variable. Although some almost look like their parents in early > January, I have seen lingering individuals at Mattamuskeet in late > March-early April that still have pale bills and a grayish wash. > > Susan Campbell > Southern Pines, NC > > >