tags: Lesser Yellowlegs, Tringa flavipes, Least Sandpiper, Calidris minutilla, birds, mystery bird, bird ID quiz
[Mystery birds] Lesser Yellowlegs, Tringa flavipes (L), and Least Sandpiper, Calidris minutilla (R), photographed at the Lake Thompson in Kingsbury County, South Dakota. [I will identify these birds for you in 48 hours]
Image: Terry Sohl, 2 September 2007 [larger view]. You are encouraged to purchase photographs from this photographer. I am happy to email his contact information to you.
Canon 20D, 400 5.6L.
Please name at least one field mark that supports your identification.
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Comments
Cool shot. The long legs and bill suggest shorebirds, and the size bears that out -- herons or ibis would be larger with heavier bills. The bill structures rule out plovers, and the fine patterns on the upperside rules out Jacanas, Oystercatchers, or either of the N.Am. Recurvirostridae (possibly all of the family?). Here in the states, that only leaves us with sandpipers. I'll leave the rest of the fun for others.
For David's sake, though -- we're clearly looking at two different species here, one tall and slender, one much shorter and stouter. I'll wait for one of the others to try the pun tips -- I'm not much good at that.
Posted by: psweet | March 15, 2010 11:59 AM
Definitely two species of shorebirds, with each of them relatively easy to narrow down to a small number of possibilities, but harder to go beyond that.
For the larger of the two, the genus name was used as the name of a US Navy submarine rescue vessel that made headlines in 1973 when it attempted to rescue a stricken civilian research submersible. For the specific epithet, I'm going with the one that reminds me of the hat-wearing half of a popular rap duo.
For the smaller shorebird, the genus is pretty much a given. I'm going with the one whose specific epithet reminds me of the common name of a playful composition by a great Romantic composer.
Posted by: John Callender | March 15, 2010 12:33 PM
I am amazed at the clarity of these photos. Each bird is so lovely.
Posted by: Tabor | March 15, 2010 12:59 PM
OK John, I think the genus of the first must certainly be "linked" to the "sea", but don't you really mean the clock-carrying rap star whose media marketing certainly ensures he is not the "lesser" of the two?
As for the second, I wonder of you would have been better going with some of the work of Johann Sebastian Bach or George Frideric Händel who often featured that style (originally adapted from a 17th-century French dance) in their compositions, but if not, that would probably be the "least" of my worries...
Posted by: David Hilmy | March 15, 2010 3:13 PM
OK, home now, and I see John's clues were enough... the straight and sharp-pointed bill on the first eliminates Tringa melanoleuca and the yellow legs help eliminate the greenish legs of Tringa solitaria...
when one enlarges the photo, the decurved bill of the second eliminates the similar (but slightly grayer-backed) Calidris pusilla and as it's in South Dakota, we don't have to consider [the black-legged] Calidris mauri...
Posted by: David Hilmy | March 15, 2010 7:07 PM
Since I've made it home, I'm guessing the more experienced folks have this all figured out. So I'll take my shot.
The bigger bird: The beak isn't nearly as long as a lot of shorebird beaks. It's neither curved up or down. I'm guessing a lesser yellowlegs, in non-breeding adult plumage. But the legs aren't REALLY yellow... so I'm not sure. And mostly, I'm just worse at shorebirds than most.
The smaller bird: my guess is an immature Baird's Sandpiper. The wing feathers look "scaly" as my Sibley's says, which is why I'm guessing an immature, though I'm not sure I'm right at all.
Posted by: Bardiac | March 15, 2010 8:21 PM
Bardiac, you're 1 for 2, I think!
Take a closer look at the leg color of the smaller bird- if you enlarge the photo you'll notice that it doesn't have the black legs of a Baird's...
Posted by: David Hilmy | March 15, 2010 8:41 PM
Well, after a quick look my money was on Gr. Yellowlegs
(I don't have my Sibley with me - I am in Europe, so I don't carry it most days ;-) but as I recall the Greater has a shorter bill than the Lesser?
& Bairds' Sandp. The wings look V long - which is a Baird's mark, but the angle makes that tricky. But I would like to check the legs and perhaps size vs Gr Yellowlegs to be sure. Leg colour is only useful when you are sure the bird is clean.
Posted by: DaveG | March 16, 2010 9:20 AM
Hey DaveG,
As I mentioned in comment #5, if you take a look at the shape of the larger bird's bill you'll notice how straight it is (and relatively short, at about the same length as the head), whereas the Greater Yellowlegs (Tringa melanoleuca) would show one slightly turned-up and relatively long (about 1.5 times the length of the head)
Posted by: David Hilmy | March 16, 2010 11:01 AM
DaveG, actually, Greaters have a longer bill than Lessers. Looking at the smaller bird, you can barely see the primaries (they're mostly hidden behind the long tertials -- characteristic of shorebirds). On a Baird's the primaries would clearly extend beyond the tail, and they don't here.
David -- I think it would be a mistake to rule out C. mauri based on range. They are a scarce annual migrant through Illinois, and a regular winter species on the east coast, so the name Western is a bit of a misnomer. I would be amazed if they weren't annual in S. Dakota.
Bardiac -- one little quibble. According to what I can find, Yellowlegs molt their primaries on the wintering grounds -- and this bird clearly shows pale edging on neat, unworn primaries. So I would age this bird as a juvenile, apparently just starting it's post-juvenile molt. (On the basis of a couple of paler gray patches on the back.)
Posted by: psweet | March 16, 2010 1:09 PM
Thanks Paul,
Although they aren't recorded as wintering anywhere near South Dakota, they are listed as a "casual migrant"...
Range Map for the Western Sandpiper, created not coincidentally by the photographer above, Terry Sohl!
Posted by: David Hilmy | March 16, 2010 3:15 PM
Hey, Grrl, I know I said we shouldn't rule out the Western Sandpiper by range, but isn't that peep a Least?
Posted by: psweet | March 17, 2010 2:32 PM
ummm, please enlarge the photo of the smaller bird- sure, the legs are dirty but clearly not black!
Posted by: David Hilmy | March 17, 2010 3:10 PM
you know, i knew that was a least sandpiper, but absent-mindedly wrote western instead. i have been exhausted and making dumb mistakes all day long. i think it's time to crawl into bed before i become a general menace.
Posted by: "GrrlScientist" | March 17, 2010 4:02 PM