[Birdtalk] more Boreal Owls

[Cliff and Lisa Weisse]

I've seen several reports of Boreal Owl recently that almost certainly 
were Wilson's Snipe based on habitat and season so I thought I'd throw 
my two cent's worth in. 

Boreals Owls are calling most actively in late March/early April here in 
Island Park, Idaho and I would guess they're even earlier in UT.  They 
will respond to tapes in summer and occasionally sing.  Outside of 
courtship it's usually dark when they start singing-they do sing in the 
morning but not after daybreak so singing at 8:00 am would be very 
unusual. 

The winnowing of snipe is very similar to the singing of Boreal Owls.  
There are several ways to separate these two sounds.  Aside from a basic 
difference in sound quality the winnowing of snipe trails off, or fades 
out, at the end of each bout and Boreal Owl does not.  Pay particular 
attention to the cadence.  Bouts of winnowing come at evenly spaced 
intervals, Boreal Owl's song phrases are spaced unevenly, usually almost 
exactly as you hear them on tapes - groups of three phrases with the 
first two fairly close together, followed by a longer pause between the 
second and third phrase.  This sequence of three phrases is repeated 
over and over and comes from the same location.  Winnowing is almost 
always at evenly spaced intervals and it changes direction because the 
bird is flying around. The winnowing is actually made by the tail 
feathers while the bird is diving.  They climb up, dive and winnow, 
climb up, dive and winnow, climb up, dive and winnow, etc.  I'm guessing 
that's why they sounded like they were everywhere at Bear Lake.

Hope all this is helpful.

Cliff

tmigratorius at msn.com wrote:
> Bryan, 
>  
> Thanks for the recording of the Boreal Owls.  We recently stayed 
> several nights at Bear Lake ( Rendezvous Beach, Birch Loop).  We were 
> birding at dusk in the large parking and day use area just west of the 
> main campgrounds.  The owls seemed to come from every direction.  We 
> thought we had them located just to discover they were coming from 
> another direction and  another tree.  It seemed they were everywhere.  
> We heard them several times from our camp site (quite a distance from 
> the day use area) during the night.  We were having difficulty, even 
> with Cornell's bird recordings, getting a correct ID.  It is very 
> possible that we were hearing Boreal Owls. 
>  
> Hal & Kathy Robins
> ------------------------------------------------------------------------
>
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-- 
Cliff and Lisa Weisse
Island Park, Idaho
cliffandlisa at octobersetters.com

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