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Index of Subjects I should add that a good field guide is pretty important in this situation - I find the best are Sibley and the latest edition of NGS. Also, that like all other creatures including homo sapient, races are often mixed and not always separable on field marks! Richard Stern sternrichard@gmail.com Sent from my iPhone On Jul 22, 2012, at 12:34 PM, Rick Whitman <dendroica.caerulescens@gmail.com> wrote: > Thanks Richard, nicely done. I suspect the case is closed. > > I might have mentioned yesterday that at that same location I > witnessed my first Peregrine Falcon attack of this season. There were > 300 Semipalmated Sandpipers, which I was studying one by one, but they > all left in a very tight ball & they did not reappear on that high > tide. > > Rick. > > On Sun, Jul 22, 2012 at 10:24 AM, Richard Stern <sternrichard@gmail.com> wrote: >> Hi Rick, >> >> As I haven't seen any other reply, I'll have a go, and at the same time go >> through the process, which might be more educational to people than a one >> word answer. So with Dowitchers, no question that there all kinds of ID >> difficulties, but if you work through it methodically (and the photos really >> help) you can usually come to a conclusion ...... >> >> The bird has a relatively flat back, very little rusty color on the >> underparts, doesn't really have barred sides of the breast, and more >> importantly is in salt water habitat in July (as against brackish, marshy >> habitat in November) so the odds are 99.9% that it's a Short-billed, not a >> long billed (don't rely on bill length - it's irrelevant, and the birds are >> poorly named for field ID purposes). >> >> Then, as with any difficult shorebird, try and decide whether it's in adult >> breeding, winter, or juvenile plumage. This bird is in worn adult plumage, >> with an irregular, worn and "dirty" look to the uppersides. If the bird were >> in juvenile plumage, that would make it easier to distinguish from juv. >> Long-billed. However, it does make it easier to distinguish the 3 races of >> Short-billed. Most of S-B Dowitchers in NS would be griseus, which has >> relatively little rusty on the breast, and which this bird looks to me like >> it fits perfectly. The more central race, hendersoni, looks like a >> Long-billed, and the westerly race, which migrates down the W. coast, also >> looks more like a long-billed. I suspect that in true juv. or adult winter >> plumage, however, the 3 races would be pretty indistinguishable in the >> field. >> >> So for these reasons I believe the bird in the photos is a worn adult >> breeding-plumaged Limnodromus griseus griseus, which would likely comprise >> the vast majority of all the dowitchers in NS in July. A side-on picture in >> flat lighting to really illustrate the pattern of spotting and barring, and >> the extent of rusty on the breast/ belly, would be better however for this >> purpose. >> >> I should add that years ago in July 2 dowitchers landed on the bridge of a >> whale-watching boat in thick fog off Brier Island. I was very struck by the >> extent of bright rusty on the underparts, but that they didn't have the >> dense breast barring of Long-billed. So I wondered if they were hendersoni >> Short-billed, and indeed that was confirmed when people far more >> knowledgeable than I saw the pictures. >> >> Now the challenge ........ Someone please tell me if I'm wrong!! >> >> Richard >> >> On Sat, Jul 21, 2012 at 6:35 PM, Rick Whitman >> <dendroica.caerulescens@gmail.com> wrote: >>> >>> I got some pretty definitive photos of one Short-billed Dowitcher >>> today, on the point S of East Point at N. Grand Pre. A series of four >>> starts at the direct link. >>> >>> >>> http://rickwhitman.smugmug.com/Nature/Shorebirds/22686725_mPvQtv#!i=1978968974&k=5rZSPtj >>> >>> I'm hoping that Susann Myers or anyone can give me the race ID from these. >>> >>> Rick Whitman >>
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