David and Chuck,
Thanks to both of you for looking closely at this bird bringing it to our attention. My gut impression is Short-billed Dowitcher, and I'll try to explain what I see that makes me think that. I could be totally wrong; so I'd be happy to read other opinions.
The first thing with dowitchers is to age them. Because it is so worn, shows barred and black feathers in the back and scapulars, it's easy to know its not a juvenile. If it were a bird hatched this year, it would be fresh and crisp, and show other characters that make ID as snap. The dark gray and worn feathers in the wing coverts and the battered tertials (long feathers over and sticking out from above the primaries) suggest this is a bird a few months older than 1 year-old. It is wearing a faded and worn 1st alternate plumage.
The strongest character separating alternate (=breeding) plumage dowitchers is the pattern on the sides of breast. Long-billed has narrow and rather widely spaced scallops, short bars with a little bit of a shallow chevroned look. Short-billed has spots there, and that's what I see, especially down the breast. Both species have bars down the flanks. Our regular migrant Short-billed have rather heavy barring, heavier than Long-billed. The bars down the flanks of Long-billed tend to get sparse and more widely spaced through the femoral (thigh) area and then pick up again aft of there. This bird matches some heavily patterned Short-billeds.
Structurally, this bird looks like a Short-billed. It stands only as tall as the juvenile Short-billed with it, and its tibia, the part of the leg from the belly to the leg joint (ankle) looks relatively short. Long-billed has long tibia, giving them a bit of a Greater Yellowlegs stature. The injured bird is also more or less the same proportions as the Short-billed with it, being rather slim through the belly and flat down the back. I will admit that the bill appears long, but it is not overly long and definitely not straight. It could be a mild deformity, but the kink and droop toward the bill tip is rather typical of Short-billed Dowitcher.
Another clue is the state of molt, or really the lack thereof. By early October a non-juvenile Long-billed hitting the coast is going to be in basic (=winter) plumage. By contrast, Short-billed Dowitcher doesn't molt until after migration, waiting until the wintering grounds. Although molt stage doesn't help along most coastal areas, Maine is far enough north that it is helpful. The Long-billeds that we see are either breeding plumage birds that have started to molt or juveniles, or basic plumaged birds. Long-billed is one of the few shorebirds that performs molt migration, and that helps especially away from the coast, i.e. any bird in the interior of the continent in fall showing wing molt is a Long-billed. By now, the wing molt of Long-billed Dowitcher would have progressed to the outer primaries, and this bird clearly hasn't even begun. Those outers are badly worn at the tips.
Lastly, this may be subtle, but the pale orangish color, even if faded by sun and wear, is not the same tone as shown by Long-billed. The pattern of remaining color is perfect for Short-billed, being strongest on the breast and fading to white in the belly and undertail. The pattern does make me curious if this could possibly be a wayward western bird (subspecies caurinus), which are larger than our eastern griseus and show similarly strong barring on the flanks.
Other characters like the width of the dark bars on the tail, wider black always on Long-billed but can be matched by many Short-billed, are not so useful unless I could see the central rectrices clearly. The angle of the line from the bill to the eye is not useful. Long-billed may tend to show a straighter line (more acute angle), but overlap is worse than it is for bill length between the species, i.e. not helpful except on extremes and then only if it can be measured accurately, which it can't.
Here is a photo of a presumed 1st Alternate Short-billed, probably one of our eastern griseus taken 30 May 2005 in Ontario, Canada. The Pine Point bird could be a worn example of such a plumage and age:
http://www.jeaniron.ca/Shorebirds/sbdowitcher0064.jpg
After all that, I'd better be on the right track, but with dowitchers one can never be sure. If it stays, I might get a chance to see it in the field and get a better feel for it.
Louis Bevier
Fairfield
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