[Greg Budney, Audio Curator, Macaulay Library] I was up on this ridge and in sagebrush habitat south of Malheur National Wildlife Refuge in eastern Oregon. The sun hadn’t been up very long, maybe half an hour, and there were nighthawks up in the air, several males displaying. The calling and booming are typically heard at dawn and early evening. A nasal peent is a call that is given in-flight, and then you hear what sounds like a truck roaring by that suddenly just disappears. And that’s a mechanical sound produced as the birds goes into a dive. Air rushes through the primary feathers, and as it comes out of the dive the rushing of air ceases and the boom suddenly stops. The Common Nighthawk is a really graceful, aerodynamic bird. It has a fairly slender tapered body, a very small bill, almost inconspicuous, long, tapered wings with white blazes right in the bend of the wing or the wrist of the wing. So as they fly in good light conditions, you see these blazes of white, flash, as the wings are raised and lowered. What I hadn’t experienced up to that point was the males coming down, diving within a meter of the ground, within three feet of the surface. What had been a distant experience, spectacular experience, hearing them call, watching them chasing one another, actually becoming a very intimate experience within meters of where I was standing. It’s a really fascinating display to watch. [Audio Recording: David S. Herr; Photographs: Doug Backlund]

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Male Common Nighthawks plummet quickly to within 1 meter (about 3 feet) from the ground during their aerial displays. Their descent is characterized by a “booming” sound, produced as air rushes through the primary feathers, an example of how some birds create sound mechanically. This display may be directed at mates, intruders, or sometimes at a passing human.