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Florida birders:
This morning I found a female first winter oriole in my yard that I am
pretty certain is a Bullock's Oriole.  Rex Rowan cam by and saw it and we
had good scope looks from as close a 60 feet --- he concurred with
Bullock's, perhaps with a dash of skepticism.

This is one of the drabbest orioles I have seen. A drab olive yellow
suffuses the supercilium, malar region (where it may be the 'brightest'),
lores, anterior cheeks, and lower throat-upper breast. The upper throat,
and rear cheek are drabber gray-olive.  A dark eyeline is prominent behind
the eye.  The resulting face pattern is what I consider 'classic' Bullocks
(but see below).  The underparts are dingy white from the mid breast to the
undertail coverts.  The tail is yellow-olive.  The back is grayish with
indistinct darker streaks.

I was reading the C-T Lee & Birch and Jaramillo exchange in Birding last
night, so I took a long look at those median coverts.  The outermost 3-4
had more white on inner webs (in the birding paper, figure 7, like the
third down in the left column); the white on the inner median coverts,
however, was less skewed (like third down in right column in fig 7).   The
overall pattern of white on these coverts is very saw-toothed, more or less
diagnostic for Bullocks according to C-T Lee.

Another feature in line with Bullock's was the background grayish color of
the wings coverts and remiges, which made for rather muted contrast of
white edges.  Baltimore is supposed ot have blacker wings.

Okay, it seemed like a Bullock's.  But then I looked at the Sibley guide.
He mentions and illustrates some other points.  One is an entire pale lower
mandible  'unlike all other orioles' in Bullocks --- I have never seen
reference to this character.  Our bird had a quite  noticable white-horn
mandible, but with a duskier tip.  The face patterns he illustrates do not
show the supercilium or eyeline I usually see in Bullocks. Instead he makes
mention of where the color is brightest: in the breast of Baltimore and the
malar of Bullocks ('our' bird may have been brightest in the malar).  The
bird we saw, however, was much more unicolored in the head, face and throat
than either the Baltimore or Bullock's that Sibely illustrates: therefore,
neither illustration is a particularly good fit.

So my question is: how definitive is the face pattern of Bullock's?  Can
Baltimore show the supercilium contratsing with drak eyeline? Maybe the
other features indicating Bullock's swamp any other consideration? And what
is with the mandible color?

I have a nice sketch, but the bird eluded attempts at photography.  If
anyone wants to see her, give me a call to arrange a visit (I have
housemates to consider).

Andy Kratter
home 352-372-3359.


Andrew W. Kratter
Collections Manager, Ornithology
Florida Museum of Natural History
PO Box 117800
University of Florida
Gainesville, FL 32611

phone 352-392-3293
fax 352-846-0287