Here is another expert opinion on the Dowitcher identification from Andrew
Haffenden who lives on Dauphin Is, AL and has studied both LBDO & SBDO birds
during migration in that region. He feels the bird seen at the lake is a
SBDO for the reasons given below.
I was down at Dauphin Is this last weekend and saw just one SBDO which still
exhibited some alternate plumage this late in the season.
Dean Cutten
Victor Harbor, SA
Australia
(Currently in Madison, AL)
From: Andrew Haffenden
Sent: Thursday, 13 November 2014 3:21 AM
To: Dean Cutten
Subject: Long-billed Dowitcher on Lake Tutchewop
Dean, I finally found the real photos, which I saved and downloaded, and
have attached. I am leaning towards SBDO, for a number of reasons. Although
in a couple of the photos the bird seems round, in others it appears sleek,
and the belly always appears relatively flat. So in this case I don't think
there's a unequivocal argument based just on shape. The bill is thick until
the very end, whereas LBDO usually narrows to a finer point, and the
downturn seems to start, to my eye, towards the end, the last 20% or so,
rather than evenly throughout. While the bill is long, I think it falls
within female SBDO range. Given the overall color, if this is SBDO, it would
be caurinus or hendersoni, and most likely caurinus on plumage. The red
color seems richer up front, on the neck, then gets lighter on the breast
and belly. This could be a light effect, but it shows in several photos at
different angles; LBDO is evenly colored throughout. The red also extends
right through to the vent and beyond, whereas LBDO usually becomes white by
that time. The white fringing to the greater coverts appears chevron - V -
shaped, extending well up the feather, rather than being restricted to the
distal end, being almost bar-like interrupted by a narrow projection of the
darker center. Though there is a lower white eye-ring, a good feature for
LBDO, as with all features there is some variation, and other features point
to SBDO. But a combination of body shape in some photos, especially where
the bird is leaning forward, the long bill, plus this, would often put the
bird in the LBDO camp. Lastly, the bird is still in worn but full breeding
plumage. LBDO starts mo(u)lting on the breeding grounds, and is well
underway by the time it departs the US for the wintering grounds, Usually
the head feathers are molted first, whereas this bird still has an
alternate-plumaged head; all coverts and scaps are also unmolted. SBDO
usually starts some molting while migrating, mostly some head and body
feathers, but is not nearly as far along as LBDO - birds I saw a few days
ago still had a lot of alternate plumage - and most of the molt occurs on
the southern breeding grounds. This would fit for a lost bird still in
breeding plumage - it is still "migrating" and hence not molting. Caurinus
winters as far south as Peru, migrating down the west coast, so being blown
or misaligning to eastern Australia would be possible - other US shorebirds
do so.
I may very well end up being wrong on this, but such is birding ID. Feel
free to share with your Aussie birder friends.
Cheers,
Andrew Haffenden
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