White stork clattering, crotoreo de cigueña comun

The adult White Stork's noisy bill-clattering is very common during the maityng displays. The bird makes these sounds by rapidly opening and closing its beak so that a knocking sound is made each time its beak closes. The clattering is amplified by its throat pouch, which acts as a resonator. The up-down display is used for a number of interactions with other members of the species. Here a stork quickly throws its head backwards so that its crown rests on its back before slowly bringing its head and neck forwards again, and this is repeated several times. The display is used as a greeting between birds, post coitus, and also as a threat display. Breeding pairs are territorial over the summer, and use this display, as well as crouching forward with the tails cocked and wings extended.