Hi,I just wanted to weigh in on the mystery warbler since I feel that the
discussion has strayed too far from Michael Hobbs' insightful comments about
the bird and its probable Oporornis roots. Despite its deserved reputation
for "skulking" and ground-dwelling invoked in an earlier
posting, Connecticut Warbler behavior in spring does match this birds'
activities well.

>From a post I sent directly to the finders earlier:
"I agree completely with Hobbs' post about Oporornis parentage. I strongly
suspect Connecticut Warbler because of the excessively long undertail
coverts and the super-long almost thrush-like legs. Spring is a good time
for the males to be low in trees and oaks are a natural choice for them too,
esp in migration."

Long undertail coverts like this bird shows are an unusual feature of
parulids; Hobbs is right to point out that only the genus Oporornis has them
approaching the length of the tail, as in this bird (this is not so much a
function of short tails as it is of long undertail coverts).

Also, the robust and long legs apparent in the side views (band size 1!) are
noticeable and an important feature of this bird but have not yet been
mentioned.

In spring in Minnesota when they are approaching their breeding grounds at
the end of migration, I was surprised to discover male Connecticut
Warblers regularly perched on understory branches where they moved slowly
and deliberately with a lot of crouching and peeking. They are often in
dense understory, but habitats with oaks are a regular draw for them. This
comports with what we've heard about this individual. This is not like
their ground-skulking behavior for which they are famous the rest of the
year.

Further, the hunched posture in most of Collin's shots and, especially, the
side shots showing the bird with its hunched head down and the tail up are
classic Oporornis poses, esp for CONW (note aberrant 4-letter code that
distinguishes the code from Colima W!).

The views of the bill in the pics are confounding: alternately looking long
then short, sharp then blunt, sometimes all-black, sometimes pale-based,
more description from Sam and Collin could be useful. CONW should show a
flesh-based stout bill, again rather thrush-like. The one picture from
below strikes me as showing an unusually broad-based bill, unusual of
warblers except for the flycatching Redstart (did it have rictal bristles?)

As for the remaining parentage, who knows! With the black breast and the
dark cap and the widespread yellow with the white belly, Bachman's Warbler
is closest. But seriously, remaining parentage should account for the dark
cap Sam mentioned, the exaggerated facial pattern, the black throat, the
ragged black-patch margin, the faint streaks on the flanks, the unpatterned
tail and back (as far as I can tell), the odd row of yellow tips barely
visible in the pics on the lesser coverts, the white belly, and whatever the
bill turns out to be. I'm not as concerned about the black breast, since
the patch shown by this bird seems compatible with the extent of black
feather-bases shown across the breasts of male Oporornis warblers--perhaps
here the expression of melanin was overactive during feather growth or
winter-ground feather wear was so strong as to completely wear off the gray
edges that normally mask some or much of the blacker bases to the feathers.
Still, I agree that the darkness of the black of the breast patch is not
typical for any Oporornis; also the black clearly extends over the throat,
not an Oporornis pattern. In my view, none of the options are that great,
though Nashville, Redstart, Hooded warbler, or possibly a lightly marked
Dendroica like Black-throated Green Warbler (BTNW) offer something in their
favor. Conversely, a hybrid without Oporornis would have to account for the
superlong undertail coverts and the robust legs. A very curious bird!

Dan Froehlich
U District Seattle

PS: as I wrote this email the stream of Western Tanagers others have noted
farther south finally passed by here: at least 10 males and females zipped
north by my treetop window just S of Ravenna Park.

--
*******************
Daniel Froehlich
President, Puget Sound Bird ObservatoryTel: 206-595-2305
www.pugetsoundbirds.org


Sound Science -- Scientific Information -- Informed Public
Puget Sound Bird Observatory studies birds and their habitats in the Pacific
Northwest to better understand changes in bird populations, to inform
decision makers, and to engage the public with birds and their needs.
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