tags: Lesser Yellowlegs, Tringa flavipes, birds, mystery bird, bird ID quiz
[Mystery bird] Lesser Yellowlegs, Tringa flavipes, photographed at the Merritt Island National Wildlife Refuge near Titusville, Florida. [I will identify this bird for you tomorrow]
Image: Steve Dolan, 29 February 2009 [larger view].
Nikon D90 with the 55-200 zoom set to 200mm (auto exposure).
Please name at least one field mark that supports your identification.
I asked my former Master Birder teacher, Dr. Dennis Paulson, about this bird's ID. Dennis is the Director Emeritus of the Slater Museum of Natural History, author of several books about birds and dragonflies, including the celebrated Shorebirds of North America: The Photographic Guide (2005). He wrote;
This bird is definitely a yellowlegs. The long yellow legs easily eliminate any other Tringa sandpiper. It's a first-winter bird, as indicated by the mostly retained juvenile feathering of the upperparts. Thus there is nothing about the plumage that will easily distinguish the two yellowlegs, although a breeding-plumaged Greater has a lot more barring on the sides than the same plumage of Lesser.
I don't think you can use the relative length of the tibia to distinguish the species, as this varies by how the bird is standing. The Lesser indeed has relatively longer primaries, but in that pose, as one of the posts mentioned, it wouldn't be safe to use that character.
The two species differ in juvenile plumage in the intensity of their breast streaking, but this individual is right in the overlap area, more heavily streaked than a typical Lesser but less heavily streaked than a typical Greater!
It's a real challenge to distinguish the species without seeing the entire bill. I can't make up my mind whether the bill looks relatively thicker (Greater) or thinner (Lesser) at its base, I guess because it is slightly open, but pushing my guess as far as I can, I would probably come down on the side of Lesser, from what I can see of the bill.
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I'm going with Lesser Yellowlegs, based mainly on the relative paucity of streaking on the flanks.
Posted by: John Callender | March 17, 2009 11:04 AM
Little hard to tell from the photo, but my guess would be Solitary Sandpiper. Obvious spotting on the back and the bold white-eye ring point to Solitary Sandpiper.
Posted by: Terry Sohl | March 17, 2009 11:13 AM
I thinking Lesser Yellowlegs as well. It's winter plummage so there would be less streaking. It looks lankier than a Solitary and perhaps it's just the lighting in the picture but the legs seem a brighter yellow than a Solitary Sandpiper.
Posted by: Kathy H | March 17, 2009 2:40 PM
Some further information, in case it helps... The bird was alone in the pond and about 10' from the shore of the pond. Initially I had a great shot from about 30' away but with the sun directly behind it and got a lovely silouette. By driving around to the other side of the pond, I got this shot but was at a fairly extreme range on the telephoto, thank ghu for the 12MP sensor!
I'm new to birding, inspired by this site and hope to get more pictures to share with you soon.
Posted by: steven dolan | March 17, 2009 6:03 PM
I'm going with lesser yellowlegs as well. Hard to differentiate size without the bill but the body gizz tells me it's not a greater. Legs too yellow for solitary sandpiper--should be greenish.
Posted by: Keith C | March 18, 2009 5:07 PM
I'm going with lesser yellowlegs also. Body seems a little smallish for the lankier greater. And the legs are just too yellow for a solitary sandpiper which should show greenish hues.
Posted by: Keith C | March 18, 2009 5:09 PM
I had forwarded this to my brother-in-law, who is a biologist in Florida. His comments:
I think it is a greater yellowlegs. My reasons are as follows:
Merritt Island NWR is well within the range of both the greater and lesser yellowlegs. Both species are pretty common in Florida, based upon my experience, with the lesser, perhaps, seeming more common. The greater and the lesser are difficult to distinguish in the field, unless they are standing close together (and that happens sometimes).
One of the key characteristics of yellowlegs are their yellow legs. Yellow is not apparent to me on the photo, yellow is a color I see pretty well, and Anne tells me that the legs don’t look yellow to her. So, if the photo depicts the true color, its not a yellowlegs.
Above, I mentioned that the greater and lesser yellowlegs are difficult to distinguish unless they are side by side. The problem here is there is nothing to use as a basis for determining the size of the bird in the photo. Two possible differences that I’ve noticed between the greater and lesser yellowlegs are (a) that the greater seems to have a longer tibia than the lesser (as it proportionally relates to the length of the tarso-metatarsus, which is further complicated by the fact that the length of the tarso-metatarsus is mostly concealed by the water in the photo), and (b) the tips of the primaries, while standing, in the greater don’t extend far past the tips of the rectrices. In the picture, this determination is complicated by the fact that the bird is bent over, raising the tips of primaries away from the rectrices. But the extended primaries look short compared to the rectrices, making me think more likely greater than lesser.
I also considered the solitary sandpiper, one of the I.D.s you indicated had been proposed in the blog. This is definitely a possibility. Again, I used the apparent length of the tibia and a ratio of the tibia to the projected length of the tarso-metatarsus (as I did in considering the comparison of the greater and lesser yellowlegs) to conclude the photo was probably a greater yellowlegs. The legs of the solitary sandpiper, to my eye, are more greenish than those of the greater and lesser yellowlegs, and the color seems to wash out on the solitary sandpiper more as the bird ages. This really isn’t much help, because of the questions about the color fidelity of the photo and my deficient color vision. The facial markings are obscured by the shadow in the photo, but I must admit that the face looks more like a solitary sandpiper than a yellowlegs. I will nevertheless stick with greater yellowlegs on the preponderance of the evidence (maybe, more correctly stated, on the preponderance of my perceptions).
Other species considered are the willet (my recollections are they are abundant at Merritt Island, the whimbrel, stilt sandpiper, and the both dowitchers.
I’m staying with the greater yellowlegs (Tringa melaoleuca). That’s my story, and I’m sticking to it (for the time being).
You are welcome to share this at the blog site if you wish.
I would be interested in the final determination, once it is revealed. The person who submitted the photo had the benefit of seeing many details that would help clarify the identification that aren’t clearly indicated in the photo.
Posted by: John S. | March 19, 2009 12:47 PM