11. Peenting and VROOMing common nighthawks.
2. Birds and Their Sounds
Mechanical (non-vocal) sounds
From page 22 in the book.
Peenting and VROOMing common nighthawks. I wonder, how many times does he peent before each display dive? How might that pattern change over time? The low-frequency VROOOM carries great distances from neighboring territories, so I could also hear if a male chooses to VROOOM just after one of his neighbors, or if they coordinate or adjust the timing of their booming display dives in any way.