Subject: [Tweeters] [BIRDWG01] Nisqually egret: wrong species?? (fwd)
Date: Jan 25 16:40:41 2011
From: Pete Fahey - peterfahey at comcast.net


Size is wrong. I don't think Pratt has seen the photo's alongside of the
Great Blue. Intermediate Egret is only slightly larger than a Snowy Egret.
The largest Intermediate does not appear to be as large as the smallest
Great Egret. I don't have recent data, but I think Intermediate also has
color bleed into the lower part of the leg, which the Nisqually bird has not
ever shown.


Pete Fahey
Issaquah, WA



-----Original Message-----
From: tweeters-bounces at mailman2.u.washington.edu
[mailto:tweeters-bounces at mailman2.u.washington.edu] On Behalf Of Ian Paulsen
Sent: Tuesday, January 25, 2011 3:58 PM
To: tweeters at u.washington.edu
Subject: [Tweeters] [BIRDWG01] Nisqually egret: wrong species?? (fwd)

HI:
Another view of the mystery egret at Nisqually!

sincerely
--

Ian Paulsen
Bainbridge Island, WA, USA
Visit my BIRDBOOKER REPORT blog here:
http://birdbookerreport.blogspot.com/

---------- Forwarded message ----------
Date: Tue, 25 Jan 2011 17:53:15 -0500
From: "Pratt, Doug" <doug.pratt at NCDENR.GOV>
To: BIRDWG01 at LISTSERV.ARIZONA.EDU
Subject: [BIRDWG01] Nisqually egret: wrong species??

Hi birders:

Pierre-Andre commented that this bird did not look as long-necked as the
European alba he is used to seeing, and seemed to have a shorter bill. Then
the light went on in my head. I had been bothered by the same thing because
our North American GWEs are also long-necked and long-billed. The reason we
are having trouble figuring out which subspecies of Great White Egret this
bird represents is that it may NOT be a Great White Egret! In fact, this
bird has every field mark of the Australian subspecies of Intermediate (or
Yellow-billed) Egret Ardea intermedia plumifera (Kushlan & Hancock
taxonomy). Note that this is not the form one would expect to turn up in
North America (A. i. intermedia of East Asia), with which I am familiar as a
wintering bird in Micronesia. That is why I failed to pick up on the clues
at first, and took the consensus ID at face value. On thing I can say from
my experience is that GWE and Intermediate egrets are not as easy to tell
apart as you might!
think. Here are the reasons why this bird could be an Intermediate Egret:

Structure:
1. This bird lacks the long neck with a sharp kink that we see in GW Egret.
Rather, it has a relatively smooth S-curve to the neck, as in Intermediate.
Yes, there is a bit of a kink, but that's OK based on what I have seen in
Micronesia.
2. The gape line extends to the back of the eye, but not beyond. This is a
tricky feature, because this is the zone where there is overlap between
Intermediate and GWE. But GWE usually has the gape line much further back
than on the Nisqually bird. It shows particularly well in the photo with
the bill open.
3. The top of the head is peaked, not flattened as in GWE. One field guide
called the shape a "rounded triangle" while another refers to the steeper
forehead of intermedia.
4. The bill is relatively short and thick, about the length of the rest of
the head, whereas GWE usually has a bill longer than the rest of the head.
In subjective terms, the bill and head shape combine to give this bird a
more gentle look than the fierce expression of GWE.

Colors:
1. I have been troubled all along by the intense orange color of this
bird's bill. In fact, it would be extreme even for a high breeding A. a.
egretta. But it is just what one would expect for A. i. plumifera as
hormones begin to kick in. The bill in this form is bright orange-red at
high breeding.
2. Loral color is fine for either GWE or Intermediate, but not this time of
year. This bird's hormones may be out of whack.
3. Leg color is also exactly what one would expect for A. i. plumifera (I
see a slight reddish tinge in some shots; Also, I think we have some mud
problems that account for the greater and lesser amount of paleness among
the various photos.) I have never seen, out of hundreds, maybe thousands,
of birds, an example of A. a. egretta with such leg color. Those legs are
always black, top to bottom, year round. Legs of A. i. plumifera are
variably dark distally and pale proximally, and approach bright red at high
breeding. In the field guides, they look just like those of the Nisqually
egret.

I would like to hear from some Australasian birders on this call. What I
have outlined took a lot of literature digging, and I found frequent
conflation of features among the 3 subspp. of intermedia that was quite
confusing.

Of course, if this bird turns out to be what I suggest, we will have to
speculate as to how it got to the west coast of North America. Could be a
ship-assisted vagrant.

Doug Pratt


Please note my new email address. After 1 July 2009, the old ncmail address
will no longer operate properly.

H. Douglas Pratt, Ph. D.
Research Curator of Birds
North Carolina State Museum of Natural Sciences
11 West Jones Street
Raleigh, NC 27601
(919) 733-7450 ex 728

*E-mail correspondence to and from this address may be subject to the
North Carolina Public Records Law and may be disclosed to third parties.*

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