Lesser Scaup

[amendegw]

I recently displayed this photo and with the title "Lesser Scaup" based upon the "racing stripe" marking on the duck's bill. Someone suggested that it should be IDed as a Greater Scaup. Since I have limited knowledge in IDing birds, I want to make sure I get it correct. Hopefully someone can nail this down for me. Shot in Cambridge, Maryland, USA on 01-15-2019.

Thanks in Advance,
...Jerry

[RobinHood]

Just wanted to say what a great photo.

Width of bill (and possibly the head shape) suggest Greater to me, but wait for the more informed.

[Jerry Friedman]

I agree about the great photo.  With the narrow black nail on the bill and especially the white on the upper side of the wing stopping abruptly at the joint, I'm in favor of Lesser, but keep waiting for the more informed.

[amendegw]

Bump! We seem to have one vote for Greater Scaup and one vote for Lesser Scaup. Does anyone want to break the tie?

...Jerry

[Sean C]

I say Greater due to the rounded head

[akiley]

This is a Lesser for the reasons Jerry Friedman mentioned, especially the fact that the white wing wing bar is only present in the secondaries, and stops before the primaries. That's diagnostic, if I remember correctly. Head shape is variable and hard to assess in one photos.

[Tony Leukering]

The head and bill coloration make this an obvious male. Thus the complete lack of white in the primaries rules out Greater. Immature female Greaters can have very little white in the primaries, but since this bird is not a female....