20 May 2010
Provo, Utah
(E-mails clip from Jeff Cooper, 11:43 PM, 20 May 2010)
[Photos]
[After a discussion about female
Rose-breasted Grosbeaks] ...What species would you call on the two
flycatcher photos in that same album?
(Clip for an E-mails from Cliff Weisse, 2:46 PM, 20 May 2010)
[Photos]
I was hoping you wouldn't ask that but
since you did I'll take a stab at them. Obviously both are Empidonax
flycatchers, which automatically makes them difficult to ID. I'm certainly
no expert on Empids but I have some experience with Willow, Hammond's and
Dusky on territory and limited experience with other species during
migration. With that caveat I'll stick my neck out and suggest the one on
the fence is a Gray Flycatcher and the one in the tree is a Hammond's. The
bird perched on the fence looks gray on the back and head, has fairly
bright white wing bars and eye ring, short primary projection, pale lores
that possibly extend across the forehead above the bill, and the bill
looks pretty narrow with well defined, sharply demarcated black tip. The
other bird appears somewhat more olive on the mantle than the gray of the
head, has bold white wing bars and eye ring, a short bill that appears all
dark below, and the primary projection appears fairly long, although
that's very difficult to judge in the single photo.
(E-mails clip from J. Harry Krueger, 5:37 PM, 20 May 2010)
[Photos]
Cliff, I agree with your deduction of the fence-sitter being a Gray
Flycatcher. A combination of overall gray appearance, small head,
indistinct eyering (doesn't jump out at you because of lack of contrast
with rest of head), black tipped bill and short primary projection
(usually an indication of a shorter migration) add up to Gray Flycatcher.
I would want the underparts to be a little less cleanly whitish, but that
may be a photo angle thing. It also seems to be in the process of a
tail-wag, which these birds do consistently downward,
The second bird on the log by upperpart
color, bill color and size, and eyering could be either a Hammond's or
Dusky Flycatcher. I would lean toward Hammond's because the primary
projection seems too long for a Dusky... but I could lean toward a Dusky
because the throat seems too white and set off from the rest of the
underparts (I find Hammond's to blend more from grayish throat into olive
chest into more yellowish-white belly on spring adults, with no clear
demarcations). I wish we had a better idea of the tail to primary
relationship, which we can really only guess at from this photo. Therefore
in my opinion, on the basis of this one photo, it's a tossup between Dusky
and Hammond's Flycatcher.
(E-mails clip from Mark Stackhouse, 9:17 PM, 20 May 2010)
[Photos]
I've had a long back-and-forth with David Wheeler today about these birds
that started by my taunting him to come up with an answer to the
flycatcher question, after he did so well on calling the grosbeak as a
female Black-headed.
At one point I said, "Trying to i.d.
empids in photographs is useful only to generate arguments."
Since Cliff and Harry have boldly gone
where we feared to tread, I guess I'll have to share some of my thoughts
on these birds, as hashed out through today's very entertaining
back-and-forth between very good friends. Particularly as I have a few
problems with their conclusions. We couldn't have a good argument if we
all agreed, could we?
My biggest problem is with the first bird
(the one on the fence). While the color seems good for a Gray Flycatcher,
I find the bill to be entirely too short. Looking at the photo, I don't
think that this is the result of fore-shortening, Gray Flycatchers have
the longest bills of the western, narrow-billed empids (Gray, Dusky,
Hammond's). I have a hard time seeing a Gray Flycatcher with this short of
a bill. Also, I think the primary projection on this bird, while somewhat
short, is a bit long for a Gray. You can see both of these features on the
attached photo of a Gray Flycatcher that I took on Antelope Island some
years ago. (if you want a better copy of this photo, e-mail me, and I'll
send you one - I didn't want to stress Birdtalk). Since the tail is too
long, and the primary projections too short, for a Hammond's, my vote for
the fence bird is a Dusky...
In general, I agree with the analysis of
Harry and Cliff on the second bird (the one in the tree). That bird would
appear to be either a Dusky or a Hammond's. To me, the bill seems a bit
long for a Hammond's. The eye-ring is wider behind the eye - good for
Hammond's. It's almost impossible to see anything about the primary
projection or the tail length in this photo, but the impression I get is
of relatively shorter primary projection, and a somewhat longer tail than
I would like for a Hammond's. The head size/shape is hard to judge from
this angle, but seems a bit too small for a Hammond's. In total, we have a
set of apparent field marks (as seen in this one photo) that conflict
between these two species. I lean towards Dusky on this bird, too, just on
gut impression.
So for purposes of argument ;-), I see
both of these birds as Dusky Flycatcher, with a very small degree of
certainty...
(E-mails clip from J. Harry Krueger, 9:48 PM, 20 May 2010)
[Photos]
Respectfully (after all we are making an evaluation based on one photo!):
Hmm... Well, so much for the bird that I think is the easiest of the two
to id. But now that I look closer and have read Mark's analysis I'm
convinced... that it's a Gray Flycatcher. :)
I don't see a "short bill. In fact, with
the bird facing away, at an angle, I believe it's impossible to gauge the
actual length. Mark's analysis still leaves out the obvious black tip,
which is uncharacteristic of Dusky (though I'll never say never.. that
they have it, that is). Also, the uniform grayish-white underpart
coloration is totally uncharacteristic of Dusky in spring (both Gray and
Dusky are quite constant in Alternate plumage, while a species like
Hammond's can be quite variable.) On the primary projection, note that the
tail is tilted down, while the primaries are at a different angle, making
the only appear longer than they are. Note that in the photo Mark uses as
an example, the tail and wings are being held at the same angle, giving a
truer impression (well, at least on a photo).
If nothing else (and I do sometimes
wonder), an exercise like this makes us look more closely at the finer
points of identification... and hopefully learn and become more informed,
better birders in the process. Sincere thanks to Cliff, Mike, David and
Jeff for taking us down that road.
(E-mails clip from Mark Stackhouse, 10:21 PM, 20 May 2010)
[Photos]
...Actually, look closely - the bird is facing away, but the head is
turned towards the photographer. Check out the distance between the eye
and the bill - there's no fore-shortening there, so there shouldn't be any
on the bill, either. I agree that the color looks more like Gray, but I'm
less trusting of color in a photo like this than structural details,
especially shades of gray/white/yellow that can be very easily washed out
depending upon the exposure/lighting, etc. The bill of a Dusky has more
black than does Gray, that has almost all of the lower mandible yellow,
except for the tip. Dusky usually has just the basal half (or even less)
yellow. Of course, if you assume that the angle of the photo only allows
the tip of the bill to be visible, then the "black tip" is all you would
see.
But, as I said above, I think that a careful look at the posture of the
bird reveals that we are, in fact, seeing most of the bill.
I'm sticking with Dusky. ;-)...
(E-mails clip from Jeff Cooper, 11:43 PM, 20 May 2010)
[Photos]
I apologize if this is only prolonging the
agony for some, but I'm learning from this discussion. I went back to the
disc and found all the photos I have for both birds.
I've labeled the files as "Empid1..." for the one on the fence and
"Empid2..." for the one in the tree. You can see all the photos by
clicking on the link below. I have also enlarged these for what I think is
the best viewing without getting too blurry. I was able to get some better
angles on the one in the tree.
Based on the discussions I've read and observing the additional photos, I
lean toward:
Dusky for the fence bird (short, mostly black bill and short primaries)
Hammonds for the tree bird (long primaries seen in backside photo)...
(E-mails clip from Jeff Cooper, 7:28 AM, 21 May 2010)
[Photos]
Thanks for posting these extra images -
especially for bird #2 (in the tree), they are very enlightening.
I agree with your call on these, Jeff. There's nothing in the new images
to change my opinion that the first bird (the fence bird) is a Dusky.
However, the two shots of the back of bird #2 give a new bit of
information that we didn't have before. Look at the primary extensions on
that bird - they are really long. That strongly supports Hammond's, and
not Dusky. The tail is also visible in those shots, and although it seems
to me to be on the longish side for Hammond's (perhaps because of the
photo angle/posture of the bird), but I think within the range for this
species. I'm pleased to see that, because the shape of the eye-ring
(thicker behind the eye) really troubled me for Dusky. Now there are three
strong features for Hammond's - the eye-ring, the all black bill, and the
long primary extension, with two features somewhat against Hammond's -
tail length and bill length, though I think both of those are within the
range for Hammond's. By weight of evidence, I lean towards Hammond's for
bird #2.
As you can see from my comments, I'm a big fan of structural features in
empid i.d. (those who know me know that it's my first choice for all bird
i.d.). Key structural characters for empids are the bill (my main focus on
western empids), primary extension, and tail length. As far as plumage
characters go, for me it's all about the eye-ring, although, as with all
plumage characters, molt and wear can affect this. I am very distrusting
of overall color, especially the color of the underparts, as I find these
far too variable between individuals and even within one individual at
different times of the year...
Photos by Jeff
Cooper (Click the "back arrow" to return
to the discussion).
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