Describes a carnivorous diet that consists of mostly birds. Some birds of prey feed heavily on smaller birds and are considered to have an avivorous diet, and other birds of prey will occasionally feed as avivores if there are plentiful birds to eat or other prey is scarce. Avivorous birds are strong, agile fliers that are capable of surprising their prey in the air or pursuing a panicked bird. They also frequently have strong legs and talons in order to grab their prey successfully on the wing, though many avovirous birds will seek to surprise prey while it is on the ground.
Both large and small birds of prey can be avivores. Urban peregrine falcons are frequently avivores and feed mostly on rock pigeons, while avivorous backyard hawks such as the sharp-shinned hawk or Cooper's hawk are more likely to feed on smaller birds such as sparrows and finches, though they will take birds as large as doves.