EURASIAN PYGMY OWL (Glaucidium passerinum)

Chevêchette d'Europe

 

The main breeding range of the Pygmy owl is in boreal forests from Norway across Russia and Siberia to the Pacific coast of the Eurasian continent. In the Alps and the Jura mountains of Switzerland occur a small population of what is thought to be a relict of the last ice-age, they hung on here when the ice retreated. They are found in the western Jura, pre-Alps and Alps in forests between 1000m - 2000m.

 

This is an unusual owl because it is diurnal - active during the day. In fact its ability to see in the dark is said to be comparable to that of humans (Voous and Cameron 1988). And it lives up (or down !) to its name "pygmy" as it is barely the size of a starling, and hunts small birds like tits (mésange), and small mammals like voles along the forest edge. But being so small it is vulnerable to larger predators itself and takes great care to use its cryptic coloration to blend in with the background and so can be very difficult to see.

 

Despite its size it is a ferocious hunter and will take prey opportunistically, hiding excess prey items in "larders" - store places in the crown of tall conifers where it will return and retrieve the food when needed. This helps it through periods of scarcity and is presumably one of the strategies that helps it survive the harsh winters of its breeding range. Like many owls it is a hole nester but this little guy uses holes made by woodpeckers, usually Great Spotted or Three-toed Woodpeckers.

Its voice is a very distinctive but monotonous series of "poop" notes all at one frequency:

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Despite being a soft note it carries for quite some distance, I was about 300m from that last recording when it was made. Closer up it is really quite powerful:

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In the first recording the calls came at intervals of 2.05 secs, in the second recording the two bouts were at intervals of one call every 1.7 secs. The first recording also had calls at a frequency of 1.32 Khz and the second was a bit higher at 1.41 Khz. The literature (Voous and Cameron 2008; Cramp et al) tells me that females call at a slightly higher pitch and more rapidly than males, but whether the differences in my recordings are of sufficient difference I cannot say and needs more investigation. Cramp et al state that the pitch difference can be up to a third higher which is much more than I recorded. So maybe my difference is simply a reflection of excitement level?

 

 

 

Here is a sonogram of the second recording, from it you can see that each note lasts for about 0.3 secs and is accompanied by a harmonic at twice the frequency (= 2.8 Khz):

This species also has a set of notes on a rising scale, the so-called "scale-song", this is used mostly at the height of territorial disputes but I have yet to experience this.

You can read more about the day and location where I made these recordings here.

 

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