Scaup

[Drpepper]

How can I determine the difference between a Lesser and a Greater Scaup?
Also, in the towards the top left corner there is a bird with extra white on its neck. Is this just a Scaup with some weird feathers or something else entirely?

[Paul O'Toole]

Here is a really good look at both species side by side. Not sure whats with the other duck and the white neck high up.

https://www.utahbirds.org/featarts/Scaup.htm

[Reuven_M]

The best way to identify is based on head shape. See here: https://www.utahbirds.org/featarts/Scaup.htm. This does take some practice. In winter in our area, Greater Scaup is far more common (probably about 1000 Greater:1 Lesser). All of your birds look like Greater Scaup to me. The one bird you point out just has one or a couple of back feathers sticking up out of place.

[Drpepper]

Thank you!

[Drpepper]

So from the website you mentioned, I would think this is a lesser scaup based on the head shape. Correct or incorrect?

[Reuven_M]

Yes!