What term describes a large, coordinated flock of migrating starlings?

A murmuration is a large, coordinated flock of starlings, often seen during migration and winter roosting.

Thousands of birds may wheel, twist, and expand across the sky in rapidly changing formations. Each starling responds to nearby flock members rather than following a single leader, allowing the group to change direction almost instantly.

Murmurations commonly appear near evening roosts, when starlings gather before settling for the night. The displays can help birds reduce the risk of attack by confusing predators such as peregrine falcons, while the flock also provides social information about roosting and feeding sites.

The term describes the flocking behavior, not a particular species or migration route. Starlings may form murmurations outside migration periods too, especially where large winter populations gather.