Date: 12/1/19 12:34 am
From: Tom McNamara <tmcmac67...>
Subject: [obol] Re: Sauvie Island (Columbia Cty.)Light morph Harlan's hawk
Hi Olin,

I have to disagree with your assertion that this bird being sized up as a
non-Harlan's is a "(can't see) the forest for the trees" situation. It's
more like: there are the trees; some are firs--- how do we reliably
distinguish which is which. It usually takes getting some details,
plural.
Just so with subspecies of redtails.
As regards plumage, I agree that the bird is sort of "cold" on the
upperparts but it's a brown-infused gray, not black and not so much as to
be disqualifying on that character alone to be out of the plumage-range of
J.c. calurus (there is a licensed picture on BNA taken by Jerry & Sherry
Liguori of a flying juv. western redtail that looks nearly identical to
this local bird). And on Jack's bird there definitely * is * a light buffy
wash apparent on the breast (not snowy white as would be expected on
light-morph Harlan's) as shown in the picture where the bird is perched;
so, no, it's not "basically a black and white bird". And so that kind of
undoes your next sentence: "That necessarily makes it a Harlan's".
If the bird, when perched, pic is looked at closely we can see:
brownish gray upperparts
that light buff breast
no atypical light coloring on the face/head and throat (as would be
expected in light morph Harlan's)
a belly band that is typical for western redtail and not "fairly distinct
blobby" streaks as Ligouri says occurs in light- morph Harlan's
inre the the leg feathering: it's totally fine for j.c. calurus

Lastly, I'll just mention that Jack took these photos right in the same
area that Ed McVicker found and photographed
( following his directions, I re-found it days later) a classic adult
light-morph Harlan's which ticked all the above-mentioned boxes. Turns
out that both Ed and I on different days saw what must have been this
very bird that Jack photographed right in the same general area. Also,
light-morph Harlan's make up only about 10% of the total of Harlan's hawks;
what kind of odds would put two light-morph Harlan's in the same
football-field sized area in western Oregon?
good birding, Tom


On Sat, Nov 30, 2019 at 7:05 PM Olin Allen <olinallen...> wrote:

> Jack, I think your original ID of light morph Harlan's is correct. This
> strikes me as a good example of a “forest vs. the trees” ID. Setting aside
> any particular field marks, my overwhelming impression about the bird is
> how very “cold” the colors are. There’s little if any hint of brown in the
> dark feathers and no trace at all of buff or rufous in the light feathers.
> It’s basically a black and white bird. That necessarily makes it a
> Harlan’s (spp. harlani). Western red-tails (spp. calurus) may occasionally
> have funky plumages, but none would ever be so devoid of color. Obviously,
> this is a light-phase Harlan’s, and it’s in juvenile plumage (meaning it
> hatched spring of this year) by virtue of the barred tail and yellow cere
> and iris. I only have one comment regarding a particular field mark. The
> feathers on Harlan’s extend further down the leg than on western red-tails,
> leaving noticeably less tarsus exposed (as on this bird), but they don’t
> extend all
> the way to the toes as with roughies. Therefore the leg feathering on
> this bird is indeed appropriate for a Harlan's. It may not appear that way
> at first glance, but the leg feathers are wet and clumped together,
> exposing more of the tarsi than normal.
>
> Olin
> ------------
> Olin Allen
> Shangri-Llama Farm
> Monmouth, Oregon
>
> On Mon, Nov 18, 2019 at 8:02 PM Jack Williamson <
> <jack.williamson.jr...> wrote:
>
> > I have more questions than answers after reviewing a few images
> > (presumably) of the same bird first found by Ed McVicker then refound by
> > Tom McNamara 16 November.
> >
> > I have labeled the following field marks for [+] and against [-] a
> > Harlan's Id this evening after reviewing images captured earlier today
> >
> > [-] Lack of Feathered tarsi
> > [+] Outer primaries appear boldly banded
> > [-] Absence of a dark belly band
> > [-] Patagials not larger/bolder than other species in the area
> > [-] Absence of longitudinal black streaks on retrices
> > [-] Forecrown not distinctly whiteish
> > [+] Yellow cere
> >
> > Looking forward to learning what I have not seen but should have.
> >
> > View the full-screen slideshow for the best resolution.
> >
> > https://adobe.ly/346t2UI
> >
> >
> > Jack Williamson
> > West Linn, Oregon
> >
>
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