STARE
Live: one falcon, 2,400 starlings
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Stare is the old English name
for the starling
Each bird watches about seven
(01) What you are looking at
A murmuration has no leader. Each starling keeps track of its nearest five to ten neighbours, and the whole cloud turns because each bird turns with them.
High-speed camera studies over Rome found that a starling holds on to the same number of neighbours however far apart they are, and that it sticks closest to the birds at its sides, where its eyes point. The flock on this page runs on that rule.
(02) Three rules and a falcon
Separation
Don't collide. Each bird steers away from any neighbour that comes too close, which keeps the cloud from collapsing into a ball.
Alignment
Fly the way they fly. Each bird matches the average heading of its neighbours, so a turn passes through the flock like a ripple.
Cohesion
Stay with them. Each bird drifts towards the middle of its neighbours, so stragglers are pulled back in.
The falcon
Flocking is thought to be about cover. When a hunting bird cuts in, the nearest starlings swerve and the swerve spreads, opening a hole that closes behind it.
The bird
(03) Common starling, Sturnus vulgaris
Glossy black, with a metallic green and purple sheen, speckled white in winter.
Short, pointed wings: built for quick turns, not for gliding.
Sturnus is Latin for starling, vulgaris for common.
The first computer flock used the three rules above. It was built for film effects.
Numbers have fallen in northern and western Europe as grassland insects for the chicks grew scarce.