Chuck-will's-widow
Chapter 7: When to Sing, and How
Subchapter: Night singing
From page 124 in the book.
♫509. Hear the distinctive chuck-WILL's-WID-ow songs of these two unseen males near their territorial boundary—one song is a little more hurried than the other. June 4,42010. Bay Creek Wilderness, Shawnee National Forest, Illinois. (4:35)
♫510. Sight unseen, one can hear how the male hurries his song when visited by a second bird, probably a female, with both male and female then calling with especially low growly notes. In the background are purple martins in dawn song flight. May 9, 2014. McClellanville, South Carolina. (2:26)