Date: 10/23/19 6:12 am
From: <clearwater...>
Subject: [obol] Re: Slender-billed nuthatches
Thanks, Kevin, for this useful link. The text of your posting got mushed
together so I'll give that link again here:

Vocalizations are certainly the most reliable way to distinguish between
these two subspecies in the field, as the structural differences are
subtle and there is some overlap in terms of size.

However, for birders in parts of Oregon where only one subspecies is
resident, I think it's possible to develop an eye for "typical"

In the Willamette Valley, nearly all of the White-breasted Nuthatches
that we encounter are Slender-billed (ssp. aculeata). When I encounter
White-breasted Nuthatches east of the Cascades, such as in the Warner
Mtns or Ochocos, I'm usually struck by how much brighter and more
sturdy they look. The white areas on birds in the Willamette Valley are
more of an off-white than bright white, and their bills are more

I don't think these differences are completely reliable, since the
differences are subtle and there may even be some intergradation between
subspecies where they come into contact (Hood River should be mentioned
as another area where you have a high chance of encountering both

But for Willamette Valley birders, if you spend enough time watching
Slender-billed Nuthatches in good examples of oak habitat here, I think
you'd most likely notice if you encountered a stray tenuissima, even
before you heard it.

But luckily nuthatches tend to be talkative, so it would be a rare
thing to have to rely on visual impression alone.


From : "rriparia@xxxxxxxxxxx" <rriparia@xxxxxxxxxxx>

* To : Karen Paulino <spindels@xxxxxxxxx>, obol@xxxxxxxxxxxxx
* Date : Tue, 22 Oct 2019 19:51:28 -0700

Karen,To really answer your question you can visit a link provided in the
article by Pandolfino, in Western Field Ornithologists, that discussed the
vocal differences in white-breasted can click on the
MP3 links following the aculeata and tenuissima recordings. There at least two
vocals provided for each. You can hear their distinct differences, which is
basically speed/pace, and pitch/ tone. Kevin SpencerKlamath Falls,
<ORrriparia...> from my Verizon LG Smartphone------ Original
message------From: Karen PaulinoDate: Tue, Oct 22, 2019 5:34 PMTo:
obol@xxxxxxxxxxxxx;Cc: Subject:[obol] Slender-billed nuthatchesIn the field,
how does one differentiate a slender-billed nuthatch from a white-breasted

Joel Geier
Camp Adair area north of Corvallis

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