Listening to a Continent Sing

Another Henslow's sparrow on the Regal Prairie at Prairie State Park. He's a neighbor of the bird in MO-164, yet how different his song, and far less elaborate, too, weighing in at a mere quarter second. The third bird in the background sings yet a different tune.

Is this the nature of Henslow's sparrow song, that each bird sings his own tune, irrespective of what the neighbor sings? If neighboring males don't learn their songs from each other, then local dialects cannot be maintained, and from this meager evidence such would seem to be the case.

So that you can appreciate the differences in the songs of these two birds from Prairie State Park, listen to one example from each of these two birds next:

Now we listen to those same two songs slowed down to one quarter of normal speed:

And at about 1/8th normal speed:

Background

Dickcissel, eastern meadowlark, common yellowthroat, a second Henslow's sparrow.

Photo by Wil Hershberger