Listening to a Continent Sing

Vesper sparrows! I stand in the sagebrush, and behind me is the Snake River, before me Cottonwood Creek and the Teton range, with vesper sparrows everywhere. Feel the whistled introductory notes of the bird in the foreground, how typically two whistles are slurred down followed by two higher whistles (sometimes just one) held on a steady pitch: tew tew tee tee, one might say. In the background are at least two other males with the same introduction, with the same local dialect to which most males here conform.

There's good fun to be had by studying how the foreground male generates variety in his songs. It seems that the first trill after the introductory whistles is always the same, but what comes after that varies from one song to the next. Other individuals can also be identified by their first trill after the whistles, as they differ from bird to bird.

Background

Brewer's sparrows, other Vesper sparrows, two rivers (Cottonwood Creek, which drains Jenny Lake; Snake River, heading to Hell's Canyon).

Photo by Wil Hershberger