30 June 2016, Glacier National Park

Spring starts late in the northern Rockies so many birds are still singing here in Glacier National Park. Fortunately the varied thrush is one of them.

In the breeding season the varied thrush (Ixoreus naevius) is a shy bird of mature western forests. He sings from the top of a conifer for 10 to 15 minutes but the trees are so tall that he’s hard to find. If he wasn’t singing we’d never know he’s there.

His song consists of one note that lasts two seconds.  He pauses 3 to 20 seconds and then sings again, a different note.  The disembodied sound echoes in the canyons.

Like all thrushes his syrinx allows him to blend two sounds so his note has a burry quality.  It sounds like this:

“Varied Thrush (Ixoreus naevius meruloides)” from xeno-canto by Richard E. Webster. Genre: Turdidae.

This song is unique in North America and easy to identify by ear.

Just one note.

(photo by Eleanor Briccetti via Wikimedia Commons)