Flocking

Flocking benefits vary with context. Mixed-species foraging flocks in tropical forests allow information transfer about food sources and predator vigilance without competition, as each species occupies a distinct foraging niche. Tight winter flocks of small passerines (redpolls, goldfinches) reduce individual predation risk through confusion effects. Formation flight in geese and pelicans exploits upwash vortices from wingbeats ahead, reducing flight energy costs by up to 20% for trailing birds.