I've always had trouble with dowitchers. I really have no idea on this one. Taken last November in San Luis Obisbo County, CA. This was the only shot I managed of this guy before it moved off.
Beautiful shot Aidan! Love the colors, selective focus and the low angle! You will have to wait for Artie and the other pros to id this though. Not enough showing for me to hazard a guess!
Always a tough one, and I may be totally off the wall here, but I'll have a go! There are some bright fringes on the scapulars, suggesting a juvenile bird, although it's probably molting into winter plumage. If that's the case, then the lack of bright inner markings on the tertials would suggest a Long-billed. The rather sharp demarkation between the rather uniform chest and the paler belly in basic plumage also suggests a Long-billed. A dowitcher still in this plumage in California in November is more likely to be a Long- than Short-billed, as most would have migrated on by then, especially if this bird was in a fresh water or non-coastal location. There is a detailed article on separating the 2 here - http://www.surfbirds.com/ID%20Articl...witchers2.html .
You don't have to look at the plumage to id this one. It's definitely a Long-billed by shape. Short-billed is very flat-backed and more slender. Long-billed looks fat and hunch-backed - one book describes it as looking it swallowed a grapefruit. That shape is very very obvious even at long distances and is a very easy way to separate them in mixed flocks.