Here's a remarkable recording of a huge flock of Pinyon Jays (Gymnorhinus cyanocephalus) which flew over my room at Grand Canyon, Arizona, December 12, 1997. These Jays often flock together, but this flock was extraordinary. There were perhaps 1000-1500 birds together, all calling at the same time. It's difficult to estimate large numbers, but the flock flew over me for just over 60 seconds, and was at least 50 meters wide, solid with birds!
Douglas Von Gausig (recordist; copyright holder), Naturesongs.com
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