[Tweeters] feather ID

J. Acker owler at sounddsl.com
Sat Jun 25 14:32:47 PDT 2016

Thanks Valerie, for sharing this experience.

I certainly agree that separating these two species based on a feather is
challenging, but here is why I believe it to be a GHOW feather:

Both GGOW and GHOW leading primaries are approximately 10" in length .
(http://www.fws.gov/lab/featheratlas/) I believe Valerie's feather to be a
leading primary based on the comb on the leading edge of the feather.

While somewhat similar in appearance, the shape, blotchiness (irregularness
to the banding) and proportions are different for these two species. In
the GGOW leading primary, about half the feather is oval in shape before it
radically tapers down, rather than the more 2/3 length rectangular ovoid
shape of the GHOW. In Valerie's feather, only the first band nearest the
base is "blotchy" (irregular?).{I think blotchy is a good descriptive word;
nuts to Siri}. The GHOW feather I have in my personal collection from NE
Ohio also exhibits a blotchy/irregular band nearest the base, with the rest
similar to the GHOW in the Feather Atlas as well as Valerie's. In a GGOW
feather, I would expect all the bands to be more blotchy/irregular.

If Valerie wouldn't mind taking a photo with a ruler (cm) next to the
feather, the proportions might show up a bit more pronounced. (If you do
take a photo, if you wouldn't mind taping the tip down to straighten it out
a bit more, as in the online photos.) The main feathering, the more rounded
ovoid, of the GGOW is from 6-18 cm. On the GHOW, this more rectangular
ovoid is from 6- to nearly 20 cm. The overall length of the GGOW leading
primary is slightly less than 26 cm. The overall length of the GHOW leading
primary is slightly longer than 26 cm. The overall wingspans of both species
are similar (GGOW-140-142 cm, GHOW 134-143 cm). At the greatest width, the
GHOW leading primary feather is slightly over 4 cm. The GGOW is nearly 6
cm, a noticeable difference which gives the GGOW a more rounded ovoid
appearance to the feather. (Does this make sense?)

That all being said, the differences in size between the sexes make the
above measurement comparisons somewhat suspect since we don't know the sex
of Valerie's bird. The GHOW feather from the Feather Atlas is from a male
from Oregon, and the GGOW feather a female also from Oregon. However, the
proportions argument should hold true, as well as the "blotchiness" factor.


J. Acker

<mailto:owler at sounddsl.com> owler at sounddsl.com

Bainbridge Island, WA

From: Faye McAdams Hands [mailto:zest4parus at hotmail.com]
Sent: Saturday, June 25, 2016 1:26 PM
To: J. Acker <owler at sounddsl.com>; 'Valerie Anderson' <valhikes at gmail.com>;
Tweeters at u.washington.edu
Subject: RE: [Tweeters] feather ID

Dear Jamie and Tweeters,

I don't know.....looking at my book ("Bird Feathers", Scott and McFarland)
and checking those 2 awesome resources that you shared Jamie,
I can certainly see why Valerie would say Great Gray Owl, and I am leaning
that way myself.
They are pretty similar, which makes sense.
When looking at the Great Gray's primaries, the banding looks more blotchy,
not as crisp and distinct as on the Great Horned. And the pictures shared by
Valerie seem to be more like that blotchiness. (apparently Siri says that's
not a real word).
But I'm no expert.
Could you please give more detail as to why you say Great Horned vs. Great
Thanks for the learning opportunity,

Faye McAdams Hands
zest4parus at hotmail.com <mailto:zest4parus at hotmail.com>
Belfair, WA

"Life is simple - eat, sleep, bird."


From: owler at sounddsl.com <mailto:owler at sounddsl.com>
To: valhikes at gmail.com <mailto:valhikes at gmail.com> ;
tweeters at u.washington.edu <mailto:tweeters at u.washington.edu>
Subject: RE: [Tweeters] feather ID
Date: Sat, 25 Jun 2016 12:50:38 -0700

Valerie & Tweeters,

Here is are two great resources for IDing feathers:



I believe what you found was the leading primary to the left wing of an
adult Great Horned Owl.


J. Acker

<mailto:owler at sounddsl.com> owler at sounddsl.com

Bainbridge Island, WA

From: tweeters-bounces at mailman1.u.washington.edu
<mailto:tweeters-bounces at mailman1.u.washington.edu>
[mailto:tweeters-bounces at mailman1.u.washington.edu] On Behalf Of Valerie
Sent: Saturday, June 25, 2016 12:20 PM
To: tweeters at u.washington.edu <mailto:tweeters at u.washington.edu>
Subject: [Tweeters] feather ID

Hi Tweets,

This week I was backpacking in the Teanaway region (Bean Creek/Stafford
Creek/Navaho Pass), which is just NE of Cle Elum. I found a feather right in
the middle of the trail, at about 4000 or 5000 feet elevation. Using my
feather identification book, we concluded that it belongs to a Great Gray
Owl....but I didn't know they visited that area. I have been unsuccessfully
seeking out these owls for the past few years and it would be so ironic that
I would stumble across one of their feathers when I wasn't even thinking
about them!

Any insight to confirm or reject this identification? It is about 10" in
length, and has all the characteristics of an owl feather. Sorry the photos
are not the greatest. Here's the link:


Valerie Anderson

Olympia, WA

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