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Hi folks,

If anyone is out looking for "the" Black-headed grosbeak this weekend, it
may interest you to know that there are two, maybe even three members of
this species that have been present since the discovery of Brevard County's
third occurrence of the western sister of the Rose-breasted grosbeak.  This
fact is not readily apparent from the public posts so far.  As some of you
may recall, I posted a sighting of "the" grosbeak which was contradictory to
the partial description of the bird seen Sunday morning.  From the
descriptions of the birds, two things should have been apparent.  One, there
are two different birds being seen.  Two, they are both Black-headed
grosbeaks.  Yet, sightings of this species were still being referred to as
"the Black-headed grosbeak."  In the ensuing week, I have managed to divine
a description of the bird first sighted Saturday AM and another bird that
may have been the bird present Saturday PM or even yet a third bird.  This
experience illustrates the importance of good field notes and observation
skills when observing birds.  So far, no one has observed more than one
individual BHGR in one day.  If everyone just assumed that what they saw was
"the Black-headed grosbeak" than we would not have known how unusual this
occurrence is.

So here is a basic timeline as near as I can make out:

10/19/02 Saturday AM:

The Hills find a Black-headed grosbeak answering to the description of an
immature male.  It is described as having a "uniform robin orange breast and
flanks with not even a suggestion of streaking." (Described on Sunday
morning.)

10/19/02 Saturday PM:

I found a bird that was distinctly different from the bird in the AM.  The
following is a transcription of my field notes.

Turkey Creek Sanctuary  19 Oct 02  ca. 1730

Bill:  Dark maxilla.  Gray mandible.  Distinctly bicolored.
Head:  Pattern like RBGR.  No moustache stripe.
Breast:  Yellowish-buff w. hint of orangish.  No streaking.
Belly:  Similar to breast, slightly less orangish.
Flanks:  Buffy w. faint streaks.
Vent:  Small area of whitish at bottom of belly.
Undertail coverts:  Buffy, no streaks.
Upperparts:  Tail blackish.
                    Back Blackish w. white speckles.
Underwing:  Lemon yellow tuft sticking out from folded wing.
Did not see the rump.
Bird was observed ca. 3m high feeding on Peppervine and Hackberries for ca.
5 minutes.  The sun was low in the western sky and behind me for most of the
observation.

10/20/02  Sunday AM

The bird described in Saturday AM was observed by a group of birders and
described as above.

10/21/02  Monday AM

Apparently the same bird Saturday AM was briefly observed by the Hills and
promptly disappeared.

Another observer made the following observations that either Monday or
Tuesday:

.....We found the Black-Headed Grosbeak in the Hackberry on the west side of
the
trail coming out from under the big oak.  It immediately flew into the thick
vines on the east side of the trial.  We spotted movement in the vines and
discovered the bird had changed into a Rose-Breasted.  Then we noticed there
were two birds on the vine, the Black-Headed and Rose-Breasted were feeding
side by side.  We watched the two for almost 45 minutes getting many clear
and close views from all angles.  The Black-Headed even spent some time
preening, raising his wing to give us a clear view of the lemon yellow
underside and faint but clear streaking along the side of the breast.  We
also had a clear comparison view of the beaks of the two birds, with the BHG
showing a more fleshy and obvious two-tone than the RBG.  The center of the
BHG breast was faded almost to dull white, which almost perfectly fits the
Sibley description of a female BHG with worn-out colors.

I wish we had brought a camera as both birds remained near one another,
frequently within 8-10 feet of us.


10/23/02  Wednesday AM

A grosbeak fitting this description was observed in the same area.

Bill: Maxilla darker than mandible, but neither very dark.  Very similar to
BHGR bills in Peterson's drawing.

Head:  Supercilia nearly white over the eye, shading to buffy where they met
behind the head.  Very similar to head on 1st fall male drawing in NatGeo
(2nd Ed.)  Above the supercilium nearly black like NatGeo but buffy stripe
at the center of the crown narrower than the NatGeo 1st fall male.  Had a
faint dull gray malar stripe, hardly much different from darker gray/brown
face.

Breast:  Very similar to Peterson's female and NatGeo 1st fall male.  NatGeo
calls this "rich buff" and Peterson calls it "ochre-brown".  The breast was
not as orange as the Sibley 1st summer male, but not yellow.  The NatGeo 1st
fall male breast is about perfect for what I saw today.

Belly: Lighter than the breast and a little less orangish with a central
whitish area.....

Flanks:  Lighter orangish-buff than the breast.  I did see a couple of very
faint streaks below the folded wing in the rear part of the flanks, even
less streaking than the NatGeo 1st fall male. I did not see the flanks under
the wing.

Rump:  Nearly the same color as the rear part of the flanks, dull
orangish-buff, lighter than the NatGeo 1st fall male, but much less orange
than any of Sibley's males.  Again, the NatGeo rump comes closest.

Tail: dark brownish-black above.


Also that day other observers noted this bird:

We then found the BHGB feeding in the ragweed field across the trail from
the bird we had been watching.  This bird had a cinnamon/brick red breast,
with a central chest area that seemed to be a light yellow wash.  No obvious
breast streaks were visible, and only a couple of faint side streaks were
noticed above the legs.  About this time, I decided this was not the same
bird I described previously.  That bird had clear streaking, and appeared
stockier.  The previous bird had an almost pale white central breast area.
The tail top and back area also appeared to have a pale yellow wash, as did
the obvious central head stripe.  Behind the eyes were gray, outlined in
black.  The breast color faded to pale white and went almost all the way
around the neck.
Another notable difference in the new bird was that the yellow underwing
patch had "leaked" yellow along the leading edge and over the top of the
wing near the body.

Here is my best guess from Sibley.  The first BHGB bird with streaks was a
female with "washed out" colors on the central breast.  The second BHGB (the
one seen today) with almost non-existent streaks was a first year male.

I did not get a chance to see under the RBGB wing, but saw no yellow around
the edges.  While we were watching the BHGB, a second RBGB flew into the
field.  This one was similar to the first, but had a more limited pink area
on the breast, and no river of pink running down the belly.

---------------

Are you confused yet?  I am.  However, it should be clear that there are at
least two different birds present.  It is probable that both (or all) are
immature males.  The orangish rump would seem to confirm that.  The Sibley
guide shows two very different birds as first year male BHGR.  I take these
to show the extreme variations.  Separating immature male from Adult female
may well not be possible unless the rump is seen.

At any rate, this is an interesting birding mystery.  If anyone is out
searching for the birds this weekend, please take careful notes of what you
see, including duration of observation, distance from bird, sun angle, etc.
If anyone had a camera, by all means, get some photos.

David Simpson
[log in to unmask]
Fellsmere, FL

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