Nightjar serenades best heard in brightest moonlight
05.06.11
When a friend invited me to Townsend to see a whip-poor-will nest, I jumped at the chance. Maybe, after more than 35 years of bird-watching, I'd finally get a satis-factory look at the field marks on the head and throat that distinguish whip-poor-wills from similar but larger chuck-wills-widows.
Both species are nightjars - hard-to-see, gray-and-brown birds active mainly at night. They have small bills but huge jar-like mouths that open wide for capturing flying insects in mid-air.
Identification of "whips" and "chucks" is easy only if you hear them call. Their names imitate their repetitive calls - "WHIP-pur-will" and a whistled "CHIP-wid-WIDOW."
From a distance with binoculars, I viewed the Townsend bird on the ground. I took a few photos. When the bird suddenly flew, zig-zaging through the woods, I knew by its large size it was a "chuck" - not a whip-poor-will. Measurements with calipers of two pale, splotched eggs laid directly on the ground (nightjars don't build nests) confirmed "chuck" eggs - larger than "whip" eggs.
Source: Knoxville News Sentinel