Quirks & Quarks

How Bats Avoid a Mid-Air Collision

Bats follow a simple strategy of follow-the-leader to avoid crashing into each other in the dark.
Bats emerge from a den (US Fish and Wildlife Service)
Bats fly in the dark, at high speed, in great numbers - and somehow manage to avoid running into each other. Just how they manage to do this was a problem Dr. Marc Holderied, a bat biologist from the University of Bristol, wanted to solve, so he could use their method to keep flying robots from mid-air collisions.

Dr. Holderied studied hunting bats, using infrared cameras and floodlights, and found that they have a simple strategy for avoiding traffic chaos.

When two bats encounter each other, they almost immediately match speed and direction and fall into a formation that makes complicated and elegant manoeuvres simple, and keeps them from a catastrophic smash-up. This one simple rule seems to be all they need to coordinate incident-free flight.

Related Links

Paper in PLOS Computational Biology
- University of Bristol release
Discovery News article