Wednesday, March 21

Eastern Screech-Owl and Northern Saw-whet Owl : A comparison of calls

Owls have surprisingly varied vocabularies, making the identification of heard-only birds prone to error. Two species sharing similar calls are the Eastern Screech-Owl and Northern Saw-whet Owl, both of which have whines/wails and short barks (kew/ksew) calls that could easily be confused.
The Eastern Screech-Owl wail is usually slightly tremulous at the end, which differentiates it from the very similar Northern Saw-whet Owl wail.
(12.21am, Sep, PA)



Another Eastern Screech-Owl wailing, occasional tremolos confirming identification (Aug, PA).



Compare with the Northern Saw-whet Owl whine (5.07am, Dec, PA). The saw-whet whine rises and has harmonics, unlike most screech-owl wails, and the timbre is a clear, emphatic whine wheras the screech-owl wail is a more subdued vocalization.












(12.10am, Feb, PA).


(6.50am, Nov, PA).



Both species have "kew"-like calls or barks, also similar to each other, and quite variable. The screech-owl call is often tremulous at the end, the saw-whet ksew often descends sharply. Eastern Screech-Owl kew, with bill-snapping (5.15am, Aug, PA).




Adult at dusk calling in the vicinity of a calling fledgling (8.30pm, May, PA).



Northern Saw-whet Owl "ksew" calls (12.10am, Feb, PA)



The above recordings were of unseen birds, but are typical for each species. They emphasize the importance of obtaining recordings whenever possible to aid in confirming the identity of these and other nocturnal vocalizations.

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