Hi again tweeter-folk,

Here is a summary of the responses. As might have been expected for such
a difficult identification, it was close.

Out of nine responses, 5 opted for Lesser Scaup, and 4 for Greater Scaup.

John Tubbs wrote:

I believe you have a Greater Scaup in the image. My disclaimer is that
a single image isn't always definitive (I say this despite being an
intense bird photographer, and feeling images have a ton of value in
certain situations).

1.) Greater Scaup tend to have greenish tinges to their head when seen
in the right light. Lesser Scaup tend to have purplish tinges. Often
in our typical light in the northwest, neither color shows up. Here the
green is obvious.
2.) The head shape isn't as high, rounded or with a somewhat 'peaked'
look that Lesser's typically have - along with the neck tending to be
held higher with Lessers. Although this bird appears to have a slight
peak at the rear of the head, most Lessers have a forward slope to the
top of their head in addition to being more rounded. In other words,
the head slopes from the back to the front. Here, to my eye, the head
looks relatively flat, larger and less rounded than Lessers.
3.) The bill size. It's really obvious when you have a head-on look at
the bill in relation to head size and profile, but if you study images
in field guides, this bill definitely looks larger and bulkier than
Lessers. Although the 'nail' at the tip of the bill is also tough to
see from this angle image, it looks large to me as well.

So...I would say Greater.


Mason Flint wrote:

That's an interesting shot. From a head shape perspective the bird seems to
be a bit more like a Lesser Scaup...more angular...but that could be due to
the head being wet or some other reason. The slight dinginess of the flanks,
the large bill and the apparent greenish gloss to the head make me think
Greater Scaup rather than Lesser. This just goes to show that Scaup ID is
sometimes tough even under good circumstances.


Rachel Lawson wrote:

It does look like a Lesser Scaup. The color of the head can be
variable, but the steep forehead and the little bump on the nape (where
the tuft would be if it were a Tufted Duck) are characters of Lesser.
Greater Scaups have a more evenly rounded head, and can look sort of
flat-headed. Lessers often slick their head feathers back when they are
diving actively, though.


Rolan Nelson wrote:

I think with the crown peak in the middle to foreward part of the head
like this one, you're looking at a Greater Scaup.


Dennis Paulson wrote:

I'd go with a green-tinted Lesser Scaup. Although the bill looks large
to me too, the nail doesn't look like it has as much black as is typical
of Greaters (in which more of the black is visible from the side). The
body color could be either species, in my opinion, as there is much
overlap, although I think the barring on the back is a bit sparser in
Lesser, often giving them a whiter appearance.

Generally in Greater Scaup the head looks longer, so even though the
bill is large, it looks shorter than the length between the base of the
bill and the back of the head, while in Lesser the head seems shorter,
so the bill may be no longer than that length. Your bird matches that, I
suppose as might be expected with that head shape. I have a lot of
photos of scaups, and I think the bill looks just about as large in some
of the Lessers as in your bird. It is a puzzling bird, but I would have
called it a Lesser in the field. I don't know if there have been hybrids
between those two species.


Kelly McAllister wrote:

I'd love to hear what others think on this scaup. I immediately thought
Greater when I saw the head sheen but I agree with you that the head
shape makes it a Lesser Scaup. I struggle mightily with the scaup.


Matt Pike wrote:

First off, very nice picture. I am no expert and
am most interested to see what the "experts" tell you.
I think you got it though. The shape of the head and
the fairly extensive gray on the flanks both seem good
for Lesser. The color of the head is interesting
though. Thanks for sharing.


Larry Schwitters wrote:

I would call it a Greater.

The green head.
The head shape may be a little messed up by unruly feathers, but it is
more Greater shaped.
It sure has a big bill.

Nice photo-this is fun stuff.


Larry Engles wrote:

You have it correct [lesser scaup].

Thanks to all of you,

Andrew Reding
aareding at gmail.com
>
> -----Original Message-----
> From: tweeters-bounces at mailman1.u.washington.edu
> [mailto:tweeters-bounces at mailman1.u.washington.edu] On Behalf Of Andrew
> Reding
> Sent: Wednesday, February 27, 2008 12:10 PM
> To: tweeters at u.washington.edu
> Subject: [Tweeters] any scaup identification experts?
>
>
> Have i got this one right?
>
> http://flickr.com/photos/seaotter/2264662204/
>
> Thanks,
>
> Andrew Reding
> Port Townsend WA
> aareding at gmail.com
>
>
>
>
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