A group of birds flying together in the sky is commonly called a flock.

The longer version

Flocking is a simple rule made collective. Each bird keeps a preferred distance from its neighbours, matches their heading and avoids collisions, and from those local decisions the whole group turns as one with no leader. Alignment spreads through the flock in a fraction of a second.

The payoff is safety, since many eyes find a predator sooner and a dense swirl makes it hard for a hawk to fix on one target. There is also an aerodynamic gain from neighbours' upwash. Collective nouns for bird groups are a much later fashion, largely a fifteenth-century habit among hunters.

Where this entry sits

Here you will find feathered trivia about flight, migration, nests, eggs, and the songs birds sing. Expect short surprising facts on penguins, owls, hummingbirds, and other familiar birds from gardens, forests, wetlands, and distant coastlines. The full list sits on the Birds page, where every entry is listed in order.