How do giant flocks of birds fly in tight formations without crashing?

How do giant flocks of birds fly in tight formations without crashing? A self-imposed speed limit appears to be the answer.

Gigantic flocks of birds flying in tight formations and moving forward in unison: it is a fascinating image that we can enjoy every year. Researchers have now also found out exactly how birds manage to do this without mishaps.

Some Italian researchers got to work on their wonder and figured out how a flock of birds can fly and dance through the air without any hesitation. By the way, birds do this without colliding, crashing, or losing speed.

Using computer simulations, they mimicked the behavior of starlings (Sturnus vulgaris) – birds found in large numbers in Europe and North America. It took the researchers a few tries to do so: it is not easy to copy the flying skills of experienced birds. The big challenge? Figuring out how the animals can maintain certain speeds.

Speed limit

The secret is a relative speed limitation, the researchers say in the professional journal Nature Communications. The birds – which fly an average of 12 meters per second (43 kilometers per hour) – slow down or accelerate only slightly to keep up with their neighbors.

They fly a minimum of 8 meters and a maximum of 18 meters per second but refuse to change speed significantly because that could lead to the group breaking up.

Incidentally, this speed limit applies to any swarm, regardless of size. Both small and large swarms fly an average of 12 meters per second. Each bird uses the same strategy.