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Beth Goffe
08-18-2008, 08:00 PM
I wonder if we'll see a bunch of shorebird ID assists now that migration is in swing. Would this guy be a juvenile pectoral sandpiper? Two of them landed right in front of me at Nickerson Beach last weekend and were promptly chased by a sanderling, not to be seen again.

Lana Hays
08-19-2008, 04:23 AM
Beth
The size would be helpful. I think it might be a Least Sandpiper which would make it smaller than most other shorebirds that you saw. It doesn't look to have the right bill size for a pectoral but I would expect the bill to be black for the Least.....perhaps it's covered by mud.

Beth Goffe
08-19-2008, 06:40 AM
Thanks, Lana. I saw this bird only for about 30 seconds but it looked taller in the legs than the sanderlings so I figured it wasn't a least but it could be. This guy's bill is pretty clean. There is no mud nearby, only wet sand.

James Prudente
08-19-2008, 10:38 AM
Beth,

When these birds departed did you note an obvious white rump? White-rumped Sandpipers have a fairly prominent white supercilium and striping in the face as this bird shows.

Others will chime in to make a positive ID.

Jim

Beth Goffe
08-19-2008, 05:59 PM
Jim, thanks, I thought it might be a white-rumped, too. Unfortunately, they flew away too quickly for me to notice white on their rumps. We'll see if anyone else has an opinion.

Dan Brown
08-19-2008, 07:49 PM
Hi Beth. Good shot, would like to see more light on the breast though. I am not a shorebird expert,but I have consulted my field guides and shorebird books and I think that this is a juv. Semipalmated Sandpiper. Bill shape and size in relation to the head look good for this species. White-rumped sp. should have small black streaking on the sides and a longer bill and body. The color on the bill and the legs must be from the environment somehow, because Semipalmated should have blacker bill/legs, maybe this guy had visited a sewage treatment site or an algae infested area?

Dan Brown

http://naturestoc.smugmug.com/

John Chardine
08-20-2008, 07:02 AM
I too thought the bird was very similar to the previous post from Newfoundland, hence a White-rump.

Others?

Wayne Richardson
08-20-2008, 04:36 PM
I too thought the bird was very similar to the previous post from Newfoundland, hence a White-rump.

Others?

John: Defintely not a White-rumped - see my reply to previous post! ;)

Beth: A perplexing image. However, before I respond fully, will you please confirm that there is no webbing on the toes.

Cheers: Wayne

Beth Goffe
08-21-2008, 08:06 AM
Hi Wayne, no, there is no discernable webbing on the toes at least in this image. I want to take a look at the other one I managed to get just to be sure.

David Tyrer
08-21-2008, 06:15 PM
I believe that is a fresh plumaged, juvenile, Semi-Palmated Sandpiper. In my opinion the beak appears yellow/green due to sun highlight, but is actually black. The leg colour can vary in juveniles.

Arthur Morris
08-22-2008, 08:26 AM
I keep suggesting that folks get a copy of "Shorebirds; Beautiful Beachcombers" and study it to learn the very basics of shorebird ageing and identification.... Notice that aging is first... Shorebirds with warm colors, evenly patterned upperparts, and fringed feathers (like this bird) are juveniles. And the timing for either juvenile Least or Semi is perfect as they arrive in early AUG, with Leasts typically preceding Semis by a few days to a week. Pectoral Sandpiper is typically a bit later but can be ruled out here as pects in any plumage in North America feature heaving densely streaked breasts with an obvious demarcation where the streaking ends.

White-rumped is way off base. First, and most importantly, white-rumps have long, long wings that extend well past the tail and give the bird an elongated look. This bird has relatively short wings and a stubby look.

I am confused as to David's posts: he asks if there is any webbing between the toes and when he learns that there is none (you can see that there is no partial webbing by looking at the image) he IDs the bird as a fresh juvenile Semipalmated (no hyphen) Sandpiper. He has the fresh juvenile part right, but semis have partial webbing between the toes (thus "semi" palmated...

Juvenile semis are typically much more uniformly grey than leasts which are uniformly browner. The bill tips of all Semis are rather blunt tipped. While the bill of this bird is not as typically fine pointed as in Least, it is clearly not blunt-tipped. The yellow legs, the overall brown tones, and the fringed upperparts feathers all confirm that this is a Least Sandpiper in fresh juvenal plumage.

Pretty much everything that I wrote above is detailed in my shorebird book. You can order a signed copy from the web site by clicking on the link for Books.

If you already own the book and got it wrong it means that you need to study it... It's just like photography, if you are not ready to do the work, you are not ready to succeed.

Get yourseilf a copy of Shorebirds; Beautiful Beachcombers and you too can become a shorebird expert. Ageing and id-ing these guys is easy with just a bit of study.

Wayne Richardson
08-23-2008, 07:19 AM
Art

I've taken a far more cautious approach to this particular (juvenile) bird because:

On 1st viewing the jizz to me suggested a Semipalmated & not Least;
This bird does not resemble any of the juvenile Leasts depicted in various shorebird books, i.e. page 30 of your 'Beautiful Beachcombers', pages 156-7 of 'Shorebird Guide - Crossley et al' & page 249 of 'Shorebirds of North America - Paulson';
The presence (or not) of webbing has not yet been conclusively confirmed by Beth. Note I asked for this to be clarified & not David;
Plumage inconsistiences for Least & hard parts (legs/bill) inconsistencies for Semipalmated.At this stage & with respect, it is my opinion this juvie has been not been postively ID'd. It is birds such as this that make shorebirds one of the most interesting groups from a birder's perspective.

Cheers: Wayne

PS: I've asked Beth (in a private message) to provide further image(s) in order to resolve the dilemma.

Arthur Morris
08-23-2008, 09:28 AM
Hi Wayne,

Thanks for sharing your thoughts. I have forwarded the photo to Richard Crossley, Kevin Karlson, and David Sibley. I shall post their responses here. I spoke to Richard (who was out photographing shorebirds--go figure) and will surely hear from him this afternoon.

re:

I've taken a far more cautious approach to this particular (juvenile) bird because:

On 1st viewing the jizz to me suggested a Semipalmated & not Least;The plumage is perfect for Least though as I stated, the bill is perfect for neither.

This bird does not resemble any of the juvenile Leasts depicted in various shorebird books, i.e. page 30 of your 'Beautiful Beachcombers', pages 156-7 of 'Shorebird Guide - Crossley et al' & page 249 of 'Shorebirds of North America - Paulson';
The presence (or not) of webbing has not yet been conclusively confirmed by Beth. Note I asked for this to be clarified & not David;It looks from the posted photo to have no webbing but I admit that it is a tough call from that photo.

Plumage inconsistiences for LeastI do disagree there.

& hard parts (legs/bill) inconsistencies for Semipalmated.

It appears that the yellow legs are in part covered with mud. I have seen juvie Semis with greenish legs but never yellow. Then again, I have never seen either species with a mostly yellowish bill.

At this stage & with respect, it is my opinion this juvie has been not been postively ID'd. It is birds such as this that make shorebirds one of the most interesting groups from a birder's perspective.

We both agree there. If I am wrong, then I will tip my hats to you and the others who called it or inferred that it was a Semi. If the three super-birders above do not all agree, then it will have to go as an unidentified juvenile peep.

PS: I've asked Beth (in a private message) to provide further image(s) in order to resolve the dilemma.[/quote]

That is good. Please try to get her to post all.

Beth Goffe
08-23-2008, 02:43 PM
All righty, as requested, some tight shots of the feet and bill of this bird. As I had mentioned, there is no webbing between the toes. His legs do appear muddy but yellow underneath. I appreciate all of the scrutiny paid to my little guy. :)


http://www.pbase.com/bgoffe/image/102068534/original.jpg

http://www.pbase.com/bgoffe/image/102068541/original.jpg

Arthur Morris
08-23-2008, 02:56 PM
Well, this is getting quite interesting. Just spent 10 minutes on the phone with Richard Crossley one of the three authors of The Shorebird Guide. He feels that the toes are unwebbed (based on the rear foot shown in the middle image above) and thus the bird is not a pure Semi, but that the head is not right for Least, "strange at best", and has lots of characteristics of Semi. He leans towards Least but is unsure of the bird's identity. My understanding is that the species do hybridize... Richard has requested that Beth post several more images of the bird in any pose as he feels that photos at time can be deceiving. You have my permission to post as many different ones as you like. Thanks!

Beth Goffe
08-23-2008, 03:35 PM
Artie, I'm sorry, this is the only other image I was able to get before they were chased away. I hope it helps somewhat.

Arthur Morris
08-23-2008, 03:39 PM
Thanks Beth. This one looks more the shape of a Least. I will let Richard know to take a look and hope to hear from Mr. Karlson and Mr. Sibley.

Wayne Richardson
08-23-2008, 07:07 PM
Hi Beth

These additional 'close-up' images support my initial impression that:


There is no webbing;
The legs are rather dark, i.e look olive to me, & the paler colour is (orange) staining;
The bill is dark with orange staining.The ID features are still mixed to my eyes, although I admit not to be have seen the full range of individual variation (juveniles - either species) in the field. :confused:

The orange staining would not be unusual to me. A lot of local saltmarsh pools dry up at this time of the year & the iron rich water leaves a rich rusty scum over the mud. No doubt the same applies over there too. Ideal for sticking to legs & bills of young shorebirds!

I certainly look forward to the comments of the experts.

Cheers: Wayne

PS: I found a hybrid myself on Marco Island. That gave me a headache too! :D If interested following this link (http://www.oceanwanderers.com/WayneRichardson.Sandpiper.html)

Arthur Morris
08-24-2008, 07:44 AM
Hey Wayne, Thanks for the link to your amazing hybrid images. I forgot to mention that Richard Crossley said after viewing the close-ups that he thought that the structure of the feet and toes were perfect for least.

As for the staining theory, have you ever seen any peeps with yellow stained bills or feet? (I have not, but I have never seen the rust-colored scum that you mention.) Lastly, with no webbing what other species are possible as one of the parents besides least (assuming that the legs are actually dark or black)? While I have no experience with hybirds it would seem that if this is a hybrid that least would be one of the parent birds.

David Tyrer
08-24-2008, 05:34 PM
Arthur: I feel somewhat maligned for being blamed of confusing you, LOL, and I apologise for putting a hyphen in Semipalmated. However, I still lean toward Semi. The prospect of a hybred is very interesting and I look forward to the experts opinions......BTW, I did order your book!!

Arthur Morris
08-24-2008, 05:50 PM
Hi David, If the bird does not have partial webbing between the toes it cannot be a pure semi... So leaning does not help! Your book order is greatly appreciated. Have not heard from Mr. Karlson or Mr. Sibley.

Arthur Morris
08-27-2008, 01:02 PM
This from Julian Hough whom I have great respect for mainly because he is a Brit <smle>


Artie, Hope you are well! Interesting photo, and while it's suggestive of Least and Semip, the plumage features are all Semip.The capped crown, prominent pale supercilium, dark ear coverts, bill shape and length and rear upperscapular pattern is all Semip, as are the inner greater coverts with a fine subterminal anchor. The breast pattern is a little more coarse than on other individuals, but i think this is probably a slightly atypical bird, somewhat dark, and obviously the color of the legs and bill isn't right for either species. If we ignore the color of the bill and legs, it fits better with Semip.

Least is wrong on head pattern (no post-ocular spot), general plumage color and shape of rear lower scapulars, primary extension past the tertials, bill shape and color (too short and blob-tipped) and possibly (middle toe) length. The only thing I can't explain away is the apparent lack of semipalmations, but I'm not 100% sure i can judge one way or the other whether they're present or absent. Also, I do think, if judging on the photographs, that the general posture of the bird (with legs looking slightly farther back, does seem to fit Least better).

Not sure I can go with the hybrid theory yet, but be interested in others' opinions. One thing i know for sure is it's a juvenile!

best, Julian

Arthur Morris
08-27-2008, 01:21 PM
Then, Richard Crossley, one of the three authors of The Shorebird Guide, who had originally stated that the sturcture of the legs and the feet were perfect for least, wrote this in an e-mail:

Artie, this photo looks like a very fresh Semip Sand. The shape, bill, wing point and primary projection, underparts and upperparts are all typical of a very young bird. The pale bare parts often occurs in very young birds and probably turned dark shortly after the photo was taken. Photos are often very misleading and it always helps when the photographer picks images that fairly accurately portrays reality - then it helps to also to be a birder! Cheers, Richard.

Arthur Morris
08-27-2008, 01:34 PM
Then Kevin T. Karlson, another of the Shorebird Guide authors, e-mailed this:

Arthur, Greetings from Dale and I, and we both give you a hug for so many years of friendship. After losing Tom recently, these long term friendships mean more and more to me.<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" /><o:p></o:p>
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As for your bird, it looks fine for a juvenile Semipalmated Sandpiper, other than the yellowish coloration to the bill, which is a bit aberrant for juvenile Semi, but not out of the question. Bare parts in juvenile birds, including shorebirds, are not representative of adult coloration, and Semipalmated often shows olive to straw colored legs, and even yellowish legs. I have attached a shot of a juvenile Semi that looks somewhat like a Least because of the yellowish legs and bright rufous feather edging, but is clearly a Semi by bill structure and body shape. Some sexually immature birds, especially shorebirds and herons/egrets, do not develop the black coloration in legs and bill until the fall, and Semipalmated juveniles typically have legs that are not black at all, but olive to yellowish. The webbing between the toes on Semipalmated is clearly visible in the photo of the bird with the uplifted right foot. This is typical of the appearance of webbing on a Semi on a raised foot, and the outline of the webbing is clear against the pale background. This webbing is very difficult to see on legs that are raised, but fairly visible on standing birds. The webbing on Semi is very minor, and consistent with the photo. You can see a very slight web between the outer and middle toes, and I say again that the webbing visible in your photo is consistent with Semi. The blow-up of the right foot has the outer toe blocking the minor webbing.

Judd Patterson
08-28-2008, 01:10 AM
Artie, thanks for requesting and then posting these various views by experts. The shorebird id game is not always clear and this was one of those situations where I was just not comfortable making a definitive call. It's great to read that we now have general agreement on Semipalmated Sandpiper with some explainable inconsistencies (the leg and bill color threw me!) Good work!

Beth Goffe
08-28-2008, 06:37 AM
Thanks for helping with all of this exhaustive research to determine the species of this guy, Artie. It's been quite a lesson in juvenile shorebird ID (which is difficult enough for me with the adults). I do wish I had more images to share but I was lucky to get these two. I hope to see more of these during the upcoming long weekend, though.

Arthur Morris
08-28-2008, 06:47 AM
Hi Beth and Judd, You are most welcome. I have been trying to post a third comment from Kevin Karlson that also supports Semipalmated Sandpiper but have been having technical difficulties because of some hidden codes in the text.

In any case there is no time like the present to state that I was wrong. I saw the yellow legs, the what looked like very brown tones to me, and the somewhat crouched posture and sold myself on least. Then I convinced myself (at first with Richard Crossley's help) that the toes were unwebbed.

Thanks also to Wayne for expressing his intitial concerns in the face of my confident (mis-) assessment <smile>.

I will try to get Kevin's comment posted.

Arthur Morris
08-28-2008, 12:00 PM
Here is the final nail in my least coffin:

Then Kevin T. Karlson, another of the Shorebird Guide authors, e-mailed this:

Arthur, Greetings from Dale and I, and we both give you a hug for so many years of friendship. After losing Tom recently, these long term friendships mean more and more to me..

As for your bird, it looks fine for a juvenile Semipalmated Sandpiper, other than the yellowish coloration to the bill, which is a bit aberrant for juvenile Semi, but not out of the question. Bare parts in juvenile birds, including shorebirds, are not representative of adult coloration, and Semipalmated often shows olive to straw colored legs, and even yellowish legs. Some sexually immature birds, especially shorebirds and herons/egrets, do not develop the black coloration in legs and bill until the fall, and Semipalmated juveniles typically have legs that are not black at all, but olive to yellowish. The webbing between the toes on Semipalmated is clearly visible in the photo of the bird with the uplifted right foot. This is typical of the appearance of webbing on a Semi on a raised foot, and the outline of the webbing is clear against the pale background. This webbing is very difficult to see on legs that are raised, but fairly visible on standing birds. The webbing on Semi is very minor, and consistent with the photo. You can see a very slight web between the outer and middle toes, and I say again that the webbing visible in your photo is consistent with Semi. The blow-up of the right foot has the outer toe blocking the minor webbing.

As for the bare parts coloration, it is wise not to put any credibility in paleness or nonconformity of bare parts in fresh juvenile birds. The amount of variation that I have seen in the thousands of Semis that I have seen this summer is incredible, with very few legs appearing blackish or even dark gray. In the blow-ups, you can see that the yellow cast is not consistent, especially in the toes and mid-to-upper leg, which is what I have noticed in juvenile Semis this past week.

After giving a workshop at Jamaica Bay Wildlife Refuge in NY this past week, I pointed out the variability in leg color on both juvenile and adult Semis at this time of year. Even adult birds are showing olive to straw colored legs as their sexual hormones are rapidly declining. There are a number of field characters that support Semipalmated Sandpiper juvenile over Least Sandpiper, even with the variation involved with both species. Some are plumage based, and others structural. First of all, the plumage is totally consistent with Semipalmated and not with Least. The scapulars are gray centered with a noticeable dark shaft in juvenile Semi, while Least have mostly dark centered scapulars with bold rusty edges. Semis can show more rust to the edges than your bird, but it shows the typical white feather edges that juvenile Semis have, with ginger colored edges to parts of some scapulars and all wing coverts. Juvenile Leasts typically show bold rust edges to the scapulars, with some white fringes, and also rust edges to the wing coverts. Your bird shows the typical ginger colored wing coverts of a Semi. Leasts also typically show a bright rust crown (although some dull Leasts can have darker crowns similar to Semi), while Semis have a darker streaked crown with rust highlights, as your bird shows, and a strong contrast to a paler gray nape. I agree with Richard that the foot superficially resembles a Least, but this difference is not so definable that a hybrid should be suggested.

The bird in question here also shows a straight bill that lacks the drooping, fine tip of a Least, and is typical of a male Semipalmated Sandpiper. This is one of the strongest arguments for Semipalmated juvenile for this bird, since Least has a bill that shows very little variation, if any, in the shape. The wide base tapering to a fine, drooping tip is a reliable field mark for Least.

In my opinion, Semipalmated Sandpiper juvenile is the most variable plumaged shorebird in North America.

Anyway, thanks for the opportunity to point out the similarities between these two juvenile peep that most birders think are easy to separate. I look at hundreds of these birds at close range each time I visit Jamaica Bay in late July/August, your old stomping ground, and marvel at the similarities between some variable birds. I do agree that the head of your bird looks more like a Least than a Semi, and the bent-legged posture also resembles Least, but I do not see enough evidence to suggest a hybrid. Least is more of a sub-arctic breeder, and does not share much breeding range with Semipalmated, which is mostly a high arctic coastal tundra breeder. They really do not nest side by side in any appreciable numbers.

I hope this adds a bit of color to your discussion. I also added a photo that I shot last week of a peep at Jamaica Bay. It has gray legs but yellowish toes, and shows a muted rusty plumage. This one should generate as much discussion as your bird. It just goes to show that variation in juvenile peep can be dramatic, and don’t place so much emphasis on bare parts color. I know what this bird is since I spent a good deal of time photographing it, and could view the body language and movements that are typical of this species. However, the photos that I created did not give a definitive feeling to the species. Kevin