Sandpiper ID

[P-A. Fortin]

As requested by John, I'm starting a thread here to discuss the identification of a sandpiper.

Reference thread is here :
http://www.birdphotographers.net/for...3134-Sandpiper

Original image:
http://www.birdphotographers.net/for...l=1#post931493


Another image of the same individual (Close-up crop, unprocessed)
http://www.birdphotographers.net/for...l=1#post932775


So far, everyone seemed to be leaning toward least sandpiper before Dan showed up to crash the party and vote for semipalmated, which actually was my first guess
http://www.birdphotographers.net/for...l=1#post932736

So I'll just vote for least-semipalmated hybrid and wait to see what you guys think

I'll add two other images (cropped, unprocessed) of the same individual from different points of view. Hope this will help.

[P-A. Fortin]

Extra image #1: Front view with raised foot

[P-A. Fortin]

Image #2: Front view

[John Chardine]

Thanks P.-A. To me the yellow legs, which show up very well in these images indicate a Least Sandpiper but I stand to be corrected.

BTW, for me shorebirds are my absolute favourite subjects. I can see you must enjoy them too!

[Daniel Cadieux]

Shorebirds are my favorite too!!

Now, I'm going to stay with Semipalmated despite the leg colour. The image in the third link (the one ending with "775") shows some webbing between the toes. Does Least have that too? Here is one Semipalmated (perhaps tentatively!) that I photographed a couple of weeks ago that was clearly different than all the Leasts it was hanging out with - and check out its leg colouring compared to P-A's.

Like you John I stand to be corrected though. This is fun!

[P-A. Fortin]

On the other hand, here's one that I posted last year that was identified as least back then:

http://www.birdphotographers.net/for...rebird-%28!%29

Legs are more yellowish. Still they just all look the same to me

[Robert Doiron]

Shorebirds are my specialty and favorites subjects to photograph. Dan is correct about the ID. This is a SEMIPALMATED SANDPIPER in JUVENILE plumage. This is not a hybrid. MOST young juvenile Semipalmated Sandpipers DO NOT have pure black legs. They rather have OLIVE legs just like these two individuals posted in this thread. This is normal. The legs gets darker with age. Unfortunately, most field guides refers to this species has having black legs which mislead people to believe that they have pure black legs all the time. Least Sandpiper's legs are yellowish (not olive) in color. Also, Semipalmated Sandpipers have partially webbed toes as clearly seen in these images (Least Sandpipers lack this webbing). The bill, which is straight with blunt tip, also fits Semipalmated Sandpiper correctly. Least Sandpipers usually have bills that are more visibly curved and that are thinner toward the tip. Juvenile Least Sandpiper's upperparts are also darker and more bright rufous as compared to juvenile Semipalmated Sandpiper.

[John Chardine]

I definitely see the semipalmated feet in one of P.-A.'s images. Least do not have any webs between their toes.

Just to say Robert, I did not base by ID on a field guide. Over the years I've worked on Semis and photographed them I have looked at many thousands of legs (sometimes for bands or flags) and I have never seen legs this colour. I suppose the reason could be that I mostly look at large flocks and the feet are usually in the shadow of the bodies above them and thus not showing any subtle colour. BTW I have also seen Leasts over the years with very subtly coloured feet.

[Robert Doiron]

Hi John. I have checked your images of shorebirds on your website. You have 5 images of juvenile Semipalmated Sandpipers (two of which are mislabelled as Western Sandpipers). In 4 of these images, you can see the legs. None of these birds have pure black legs. All have dark olive legs.

[Robert Doiron]

Regarding SEMIPALMATED SANDPIPER's legs color, here are a few references on the subject:

Chandler, R. 2009. Shorebirds of North America, Europe, and Asia, Princeton at page 225: "[...] Very small, with a medium-lenght, straight, blunt-tipped black bill and medium-lenght black (occasionally dark olive) legs. [...]"

O'Brien, M., Crossley, R. & Karlson, K. 2006. The Shorebird Guide, Houghton Mifflin, Boston, at page 145: "[...] all plumages show dark olive legs, [...]"

Paulson, D.R. 1993. Shorebirds of the Pacific Northwest. University of Washington Press, at page 246: "[...] Bill and legs black, latter may be tinged gray or greenish.[...]" and "[...] Juvenal. Legs olive in young juveniles, becoming darker with age [...]".

[P-A. Fortin]

Thanks all for your this discussion. Very instructive and interesting.

I think I'll try posting shorebirds images here once in a while just to stir up such discussions

[John Chardine]

Hi John. I have checked your images of shorebirds on your website. You have 5 images of juvenile Semipalmated Sandpipers (two of which are mislabelled as Western Sandpipers). In 4 of these images, you can see the legs. None of these birds have pure black legs. All have dark olive legs.

Hi Robert, Thanks for your opinion on the Western Sandpipers. I had posted that image here at BPN some time ago and got the initial ID wrong myself. I was corrected by Arthur Morris, who is very good with shorebird ID, and who suggested in the thread that the bird was a Western Sandpiper. BTW, see his shorebird book here:

http://books.google.ca/books?id=RUte...page&q&f=false).

The ID was confirmed by another person experienced with NA shorebird ID via a PM.

Hey, are you sure I only got two wrong?! I'm an ornithologist, not a birder and I tend to make ID mistakes quite a bit.

Thanks for the references you give in a later post in this thread. My standard reference these days for NA birds, other than Sibley, is the definitive Birds of North America accounts (I wrote two accounts and have free access). In the account, under "Bare parts, "Legs and feet", is written:

"Black; toes partly webbed. Sometimes legs and feet can be grayish or (very rarely) tinged greenish or yellowish."

Daniel's image above I would describe as showing legs "tinged greenish or yellowish". P.-A.'s images I would definitely not characterise this way- they are full-on greenish/yellowish.

BTW, apart from the Western Sandpiper, I can see two (not three) individual SESAs on my website. Whether they are juvis or nor is moot, but both have dark grey legs. There's little point in debating colour because it is very qualitative unless you conduct proper measurements against a colour standard like Munsell. However, I have something equivalent on my computer in the form of a Colour Meter. I use LAB colour to diagnose colour casts in images; see pane 10 onwards here:

http://www.birdphotographers.net/for...-John-Chardine

My colour meter shows the legs of both birds to be very close to neutral (A and B channels close around 0±). One has a warm tone to the image which gives positive numbers in the B channel indicating some yellow.

[Robert Doiron]

Hi John. A few more comments. The SESAs on your website I was referring to are images 13, 16 and 39. It is clear and NOT debatable that your SESAs and your two sandpipers labelled as Western Sandpipers are in juvenile plumage. I don't understand why this is not clear for you.

As for comparing leg colors between different images, we have to remember that different light conditions will affect how we perceive the colors.

As for the ID on your "Western Sandpiper", YES I was fully aware that you had previously posted it on BPN and that Arthur Morris had given his opinion on the ID. I respectfully disagree on the ID. Your "Western Sandpiper" looks like a classic looking juvenile Semipalmated Sandpiper. Very short bill, no sharp contrast between upper and lower scapulars, upper scapulars not extensively rufous, and strong contrast between pale face and dark crown and ear patch. All are indicative of Semipalmated Sandpiper rather than Western. It was also my understanding that your "Western Sandpiper" images were taken somewhere in the Maritime Provinces or perhaps in the Gaspe Peninsula where Western Sandpipers are very rare.

[Robert Doiron]

Hi John. It would be interesting and very instructive if you could start a new thread and repost your "Western Sandpiper" images for the purpose of having another shorebird ID debate.

[Robert Doiron]

Hi John. One last thing about P.-A.'s images as compared to the one posted by Daniel Cadieux. You wrote that "Daniel's image above I would describe as showing legs "tinged greenish or yellowish". P.-A.'s images I would definitely not characterise this way- they are full-on greenish/yellowish". I disagree.

It is the front portion of legs that are extensive olive in color. The two images posted above by P.-A. show the sandpiper facing the viewer with the front portion of the legs facing the viewer. Daniel's image show the sandpiper facing sideways with the sides of the legs facing the viewer. If you look carefully at Daniel's image, the front portion of the legs are bright olive with the sides being much darker. Same thing with P.-A. images, the sides of the legs are darker and not as extensively green or olive. This is more obvious if you view P.-A. first link: http://www.birdphotographers.net/for...3134-Sandpiper

[Daniel Cadieux]

Awesome information. Makes me glad I crashed the party over on the other thread

[P-A. Fortin]

I was not glad at first, but not I enjoy it :)

[Chris Sloan]

For what it's worth, I agree with Robert as to the bird posted in this thread and as to the mislabeled Western Sandpipers in John's gallery. I think they are quite clearly Semipalmated Sandpipers. In a quick perusal of John's gallery, I did not see any Westerns.