[obol] Re: ID of wintering whitish buteo on Sauvie Island
- From: "Richard W. Musser" <dmarc-noreply@xxxxxxxxxxxxx> (Redacted sender "mussermcevoy@xxxxxxxxx" for DMARC)
- To: "tc@xxxxxxxxxx" <tc@xxxxxxxxxx>, "dmarc-noreply@xxxxxxxxxxxxx" <dmarc-noreply@xxxxxxxxxxxxx>, "wlrisser@xxxxxxxxx" <wlrisser@xxxxxxxxx>, "obol@xxxxxxxxxxxxx" <obol@xxxxxxxxxxxxx>, "portland-area-birds@xxxxxxxxxxxxxxxx" <portland-area-birds@xxxxxxxxxxxxxxxx>
- Date: Tue, 24 Feb 2015 16:48:04 +0000 (UTC)
Hello, When looking at plumages of red-tailed hawks, one must be careful to
understand the, "state of the science" at present. The photos of various
red-tailed hawk subspecies, taken on migration, are basically worthless as to
identification of subspecies. The work done showing all of those "harlans
tails" is attributed to that subspecies----but I maintain that doing this is
just a gross guess----and that there is no way to attribute those tail patterns
to "harlani"----other than to guess. Also mentioned are Krider/ Harlans
crosses. This would mean that these two subspecies live in the same area----and
I've never observed this, nor do I know anyone that has. To figure out
red-tailed hawk feathering, first we'll have to separate out the
red-tails----and it will likely take DNA analysis. It may be that there is
another species, or two, mixed in with the RTs----which causes this extreme
variation in feathering. If this were the case, the vast majority of oddly
plumaged red-tailed hawks, would be hybrids. I'm confident that if the
photo posted by WLRisser was labled, "Taken in Iowa in Feb."----it would be
called a "Kriders." All this said---one may ask, why doesn't this apply to
other bird species? I say---it does! But many bird species are much more
narrowly defined----within raptors, our NA goshawks, Harris's hawks, and
prairie falcons (for example), do not show great variation----and this allows
us to identify them by sight (how they appear to us). However, appearance is a
very rough gauge when considering subspecies of RTs. Just consider gyrfalcon
coloration----ranging from almost completely white, to almost black---yet we
term all of these, as gyrs.
I do commend the authors of the articles mentioned by Tom C., because it's
these guys that are attempting to figure this out. I really agree that photos
of adults with their youngsters, taken in natal areas, will help clarify the
"plumage problem." Another hawk species that has lots of variation is our
Swainson's Hawk, and it too may be some sort of combination of
species----awaiting untangling by scientists. This is where I see the state
of the science when it comes to figuring out all of the variation we see within
the birds we call Buteo jamaicensis. Best regards, Dick Musser (4 mi. NW of
Vale)
On Monday, February 23, 2015 5:43 PM, Tom Crabtree <tc@xxxxxxxxxx> wrote:
This is a light-phase Harlan’s Hawk, perhaps with a bit of Wetern Red-tail in
him. A Krider’s Red-tail not have a dark banded tail like the picture shows.
Birding has had a series of good ID articles on Krider’s and Harlan’s. Here
are some links to them.
https://www.aba.org/birding/v42n2p38.pdf Krider’s
https://www.aba.org/birding/v42n2p30.pdf Harlan’s
http://www.aba.org/birding/2009.html then scroll down to the January Issue and
there are two articles on the variation in tails of Harlan’s Hawks.
I’ve had the pleasure of observing multiple Harlan’s including at least two
light phase birds on my winter raptor survey for East Cascades Audubon over the
last few years. Brian Sullivan ID’d the first light phase bird that I saw in a
plumage almost identical to this one.
Nice find,
Tom Crabtree, Bend
From: obol-bounce@xxxxxxxxxxxxx [mailto:obol-bounce@xxxxxxxxxxxxx] On Behalf Of
Richard W. Musser (Redacted sender "mussermcevoy@xxxxxxxxx" for DMARC)
Sent: Monday, February 23, 2015 2:18 PM
To: wlrisser@xxxxxxxxx; obol@xxxxxxxxxxxxx; portland-area-birds@xxxxxxxxxxxxxxxx
Subject: [obol] Re: ID of wintering whitish buteo on Sauvie Island
Hello,
This appears to me like a KRIDER'S RED-TAILED HAWK. I recall trapping an
individual that appeared just like this one (in north central Illinois) about
50 years ago. When I lived in Alaska, I got to see many harlans RTs, but I
never saw one that had such a clear white chest as this immy. While living in
Alaska, I saw a few western RTs mated with Harlans, and their youngsters'
plumage was as diverse as you might expect, but the fronts of these youngsters,
(along with harlan/harlan matings) normally aren't so white. Just my two cents.
Best regards, Dick Musser (4 mi. NW of Vale)
On Monday, February 23, 2015 12:31 PM, WLRisser <wlrisser@xxxxxxxxx> wrote:
Tom McNamara was the first to call attention to the apparent immature red-tail
on Sauvie Island that had a lot of white in its plumage. Some of you saw this
bird: it hung around the area on Reeder Rd. where Oak Island Rd. turns off. It
often perched on the traffic signs across from the entrance to Oak Island Rd.
It was pretty clearly an immature red-tail but not a typical western red-tail
subspecies. Jan took some pictures that we sent to the hawk guru Brain
Sullivan who was kind enough to reply. He said that it is “mostly a Harlan’s
hawk but not a totally classic one.” He couldn’t rule out some intergradation
with another subspecies. He said that the streaked crown, white breast, and
fail thick tail bands seemed perfect. The belly band was fine. The flight
feathers weren’t classic for a Harlans, which has usually had boldly banded
outer primaries, but not always. He concluded that “there’s enough Harlans
here to call it that in eBird, so please do record
it as such!”
Jan’s photostream is below if you want to look at this bird.
https://www.flickr.com/photos/janrisser/sets/72157649893268097/
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