Birds of a feather land together - How flocking birds avoid colliding when they touch down

[Chris Merkord]

From The Economist

Landings are the most perilous parts of flying. Airline pilots have to practise hundreds before they can carry passengers. Even then, they have co-pilots, air-traffic controllers and all sorts of gadgetry to help them. And they do it one plane at a time, on clearly marked runways. Now imagine swarms of aircraft all trying to land together on a small stretch of water with no assistance and no gizmos. The result would surely be disastrous. Waterfowl, however, frequently land in groups on featureless bodies of water, yet they rarely collide. So how do they manage it?

To find out, Hynek Burda, of the Czech University of Life Sciences in Prague, and his team of 11 zoologists armed themselves with maps, binoculars, compasses and anemometers. With these they observed the landings of nearly 15,000 birds of 14 species belonging to 3,338 flocks scattered across eight countries over the course of a year. The upshot of this ornithological marathon, published in Frontiers in Zoology, was a discovery remarkable in its simplicity: no matter from which direction a flock of birds approaches a body of standing water, its members usually land on it in alignment with the direction of the Earth’s magnetic field.

 

Read more: http://www.economist.com/news/science-and-technology/21583591-how-flocking-birds-avoid-colliding-when-they-touch-down-birds-feather-land