I wonder, do they think enough to be using it for target practice? Is there some kind of signal that migrating flocks use to let it fly in unison? Or is it just like women in a restaurant - when one stands up to go, the others think "Oh, I need to do that too."
Realistically, of course, I know that it's probably just that they all ate at the same time and flew the same distance, so they all need to release at the same time. But still.
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