Peregrine falcons eat mostly birds, of an enormous variety – in North America, 450 species have been documented as prey. Peregrine falcons have been observed killing birds as large as a Sandhill Crane, as small as a hummingbird, and as elusive as a White-throated Swift. Typical prey include shorebirds, ptarmigan, ducks, grebes, gulls, storm-petrels, pigeons, and songbirds including jays, thrushes, longspurs, buntings, larks, waxwings, and starlings. They occasionally pirate prey, including fish and rodents, from other raptors. Peregrine Falcons also eat substantial numbers of bats.
With brightly lit towns and cities, new hunting opportunities have arisen for diurnal raptors living in urban areas. Many migratory birds initiate migratory flight during the period between sunset and darkness, and urban peregrine falcons have often been reported as exploiting this nocturnal prey resource at sources of artificial light.