If you have been fortunate to experience this elegant and mysterious display, you would not soon forget it. Murmuration refers to the phenomenon that results when hundreds, sometimes thousands, of starlings fly in swooping, intricately coordinated patterns through the sky. This behavior is thought to help evade attacks from birds of prey.
Dutch Starling Murmuration 2:01 (full screen with sound on is best)ARVE Error: Invalid URL
This link offers a bit of ‘how’ and a theory of ‘why.’
The Math and Mystery of Murmuration 3:49