I photographed this Dowitcher in Memphis, TN on 9/13/14. This adult has already completed the entire head/body molt, unable to get a good photo of the flight feathers, but they looked pretty fresh from what I could see. Adult Long-billed often complete this molt on the way south at stopover locations, but Short-billed are typically thought (I think) to not finish this molt til they reach the wintering grounds. Has anyone seen a full-basic known Short-billed in the interior like this?

This bird never vocalized, but responded visibly to Long-billed playback (raising its head from the sleeping position and looking around and up for about 30 seconds), with no response to Short-billed playback. This could have been a coincidence I understand. Some features could go either way on this bird. My personal thoughts:

Pro Long-billed:
1) In both photos I got in flight, lesser underwing coverts are unmarked white and contrast with rest of underwing.
2) No primary extension at all; found a photo which shows primaries falling just short of the tertials, they appear to be new with crisp fringing, which should make the bird a Long-billed.
3) When feeding, very fat "swallowed a grapefruit" look most of the time
4) At rest, body posture quite high, not more horizontal like typical of Short-billed (Short-billed is variable in this regard I know)
5) Heavy dark flank markings
6) Postscript: found additional photo which shows the tail well, with broad black bars
7) Not a feature I've always been able to use, but the supercilium shape looks great for Long-billed, very straight with slight angle from gape to eye, not strongly arched like Short-billed due to its eye being placed higher on the head.

Pro Short-billed:
1) Obvious whitish fringes on many coverts definitely more likely on fresh Short-billed (shown by basic Long-billed in very fresh plumage as well)
2) Breast not as uniformly dark as often seen in Long-billed,but still fairly uniform and with sharp contrast to white belly.

The bill could go either way to me, though obviously not a long-billed female Long-billed. The subtle kink is back up the bill a good bit, not right near the tip as typical of Short-billed. At times scaps seemed to have noticeably darker area in centers, but in some photos this doesn't come thru.

AFTER MANY COMMENTS, THE VAST MAJORITY OF PEOPLE AGREED THIS IS A LONG-BILLED, INCLUDING KEVIN KARLSON, AS EXPECTED IN THIS PLUMAGE.