White-throated Sparrow, Boulder Co., Oct. 4

[Ted Floyd]

Hello, Birders.

A little while ago this sunny Saturday morning, Oct. 4, Andrew and I saw and heard a White-throated Sparrow along the shore of Waneka Lake, Boulder County. The bird was just northwest of the playground. The White-throated Sparrow exhibits a balanced chromosomal polymorphism; the bird we observed was of the black-and-white ("bright" or dominant) morph. In the past week, White-throated Sparrows have been putting on a good show just to our north; a week ago, Andrew and I (and others) saw at least 4 just outside Cheyenne, Laramie County, and a few days later, birders in Casper, Natrona County, found at least 12.

Here is a recording of the flight call of the White-throated Sparrow at Waneka Lake:

http://www.xeno-canto.org/197803

Spectrographically, the flight call of the White-throated Sparrow is unique, being double-banded, high-pitched, descending, and wavering or trilled toward the end. This is what the Waneka Lake bird "looked" like:

In the immediate vicinity were Orange-crowned, Wilson's, and Audubon's warblers. Also, surround-sound Allard's ground crickets. No Sandhill Cranes for us yet, but we have ears cocked to the sky...

Ted Floyd

Lafayette, Boulder County, Colorado