The dark, smudgy streaks on Xavi Bou's photographs suggest the jerky ink tracks created by a malfunctioning printer, but they actually record the various patterns birds trace while flying in flocks.

Scientists have established what could be considered a baseline map of annual avian functional and species diversity patterns in the U.S., finding that functional diversity patterns in the West, where ...

New research shows mountain birds move up and down slopes to save energy, find food, and avoid competition across seasons.