This is driving me crazy. I can tell Greater from Lesser Yellowlegs when they are side by side or when they are near another species whose relative size I know (or can look up). Otherwise, I'm clueless. I have studied Paulson's Shorebirds of North America, The Shorebird Guide by O'Brien, Crossley and Karlson, plus Sibley, etc. If anyone can help, I'd be eternally grateful. First photo is of a Yellowlegs taken an Baskett Slough on Sept. 19. Second photo is of a Yellowlegs taken an Baskett Slough on Sept. 20. Is it possible to tell what they are from these photos? If so, how?
I am making progress on the Western vs. Least problem: I just look at the legs.
Addendum: Two knowledgeable birders have responded to say these are both Greaters. The base of the bills are bulky. Lessers have needle-like bills. Okay, here's a photo I took at the Oregon Shorebird Festival of 2 Greaters and 1 Lesser. (I know because of the size difference.) I"m not sure I would be able to call the Lesser's bill needle-like if I didn't see it with the Greater. Is there anything else to be seen in this photo that is different between the two (other than size)?
I am making progress on the Western vs. Least problem: I just look at the legs.
I am no expert, but I can tell you what I look for. It's hard to tell from the angle in your photo with both Greater and Lesser, but the bill of the Lesser is kindof like a needle poking out of its head rather than looking almost like an extension of the head like the Greater's. Another thing is the length of the wings vs the tail - the Greater's wings are slightly longer than the tail when standing. Lessers look skinnier to me too. I'm sure I'm not using any of the correct terminology but hope it helps...
ReplyDeleteThanks, Dawn, your "inexpert" comments do, indeed, help. I noticed that it was difficult to tell where the head ended and where the bill began on the bird today, so telling me the Greater's bill is like an extension of the head while the Lesser's is like a needle poking out of its head really does help! Also, my old Peterson field guide says Lessers are about the size of Killdeer; Greaters more the size of Willets. Surely if I remember to think "Killdeer", I'll know if the bird I'm looking at is that size or considerably bigger. I think I've been making this too hard.
ReplyDeleteBill is 1-1/2 times length of rest of head and slightly upturned, thus Greater. The legs and "knees" (actually ankles) are thick, thus Greater.
ReplyDeleteSee: http://nwbackyardbirder.blogspot.com/2010/09/id-yellowlegs.html
Bill length is highly variable, Greg, and some do not show any upturn, but the knees tip is very useful! I'm looking for tips not just for the particular birds photographed, but for Greater/Lesser in general.
ReplyDelete