Posted by Phil Pickering (208.46.229.26) on September 03, 2002 at 16:50:51:
This is fun, although I'd suggest that the whole point of this exercise is to "try hard" to find apparent differences between species, and see if they are of any actual value. Although I've personally been confused by it, I've seen/heard birders much more experienced than I refer to bill shape as a useful supporting mark for dowitcher ID - if there's too much individual variation for it to be of any use at all on a lone bird, many of us have certainly learned something.
Dennis Paulson's comments are interesting, and focus a point that I've thought about many times concerning the June 2001 quiz at this site. The upper left bird, which, based on shape and belly color, seems to be the most ambiguous of the four, as far as I can tell also appears to be by far the most progressed in body feather (and mantle feather) replacement (August 9, Santa Clara county). Is this bird's molt progressed enough to suggest that this could be a Short-billed hanging out with Long-billed? Or could there be some variation in molt timing among populations that migrate on differing schedules, or that use different stopover/wintering areas, so that the difference in adult pre-basic body molt timing is not as clear cut south of the Pacific NW?
Cheers,
Phil