What do birds eat?

Birds eat a wide variety of foods. Among them there are predators eating rodents, small birds (eagles, falcons), insects and their larvae (tits, swallows, woodpeckers), leaves and stems of herbaceous plants (geese), seeds (crossbills). Many species of birds are omnivorous, consuming both plant and animal food (crows, rooks). Since food is captured by the beak, the structure of the beak can be used to judge the food specialization of the bird.