old/new dows

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: For those that read my comments on the previous dowitcher quiz (July, 2001), and might have the impression that I knew what I was talking about, I didn't. The tertial etc. barring angle difference was just an on-the-spot theory that I was grasping at because nobody else was commenting at the time. I've since found it to be largely useless, at least on the west coast. Some hendersoni apparently do have more perpendicular upperparts barring than any L-b, but most caurinus are pretty similar to L-b in that respect. I was totally misinterpreting the barring angle in that photo, anyway. After studying it closely, I think those birds are actually reasonably "angled" and within range of L-b. I don't otherwise see anything wrong with Joe's reasoning for L-b. The upper right bird in particular is all L-b shape-wise, with ultra long legs, and an elongated look to the face that I think is probably outside the range of appearance for S-b. The central birds do seem to have too much color on the belly for caurinus, and I think the upper left bird does also, considering how worn its underparts markings are. : As for THIS bird, based on my (highly suspect) expertise, I'm goin' with Short-billed. The first thing that jumps out at you here is the almost total color fading, but ALSO retained solid, thick underparts markings, particularly heavy spotting on the throat. My impression is that this is better for caurinus, and probably a typical look for adults in July. Because L-b's dark underpart/throat markings are (on average) finer and more confinded towards the feather tips, my impression is that they tend to wear away quicker than those of caurinus, and a L-b with this much fading would (typically) not retain markings this solid, if it even had them to begin with. : I think another key is that the flank markings appear to exend down onto the belly - better for caurinus. My impression is that on L-b the flank markings typically end at the belly edges, and the belly is usually pretty clear. I'm not sure how consistent this is, but I think it has the potential to be diagnostic for caurinus in this case. Will have to do some photo study on this. : There does appear to be some color on at least the upper belly, but it appears more mottled than solid, and perhaps not out of range for caurinus. If dows are anything like large gulls, the belly feathers are among the last of the body plumage to show wear and fading, and to molt. I think a bird of either species that is largely faded might still retain most of it's alternate belly color. : The apparent primary extension beyond the tertials does seem quite extreme for L-b. I've checked this in numerous photos, and, although perhaps not diagnostic, it's a pretty strong supporting mark for caurinus in this case. : I've looked at bill shape a lot too, and am totally confused. My impression IS that some S-b can show a slight droop to the tip, although I don't recall noting one with this obvious a droop. In any case, my feeling is that bill shape is probably too variable to be more than a supporting mark either way. : OK, time to wait for Joe to tell us it flew and said "keek". : Cheers, : Phil

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