I have observed many many instances of Dunlin murmurating, but it is a very
small percentage of the time they are actually evading a predator. I always
presumed that the interim activity was "practice". You have got to hone
your skills before that Peregrine arrives. The murmuration takes on a
different form during these "practice sessions". They are much less complex
and less likely to split into separate groups. Lately I have had my best
viewing on inland flooded farm fields. The Dunlin move in there during high
tide.

Nancy Morrison