Rotte di homing e attivita di foraggiamento degli uccelli studiate mediante l' uso di un data-logger: risultati conseguiti e prospettive per il futuro.

A new type of bird-borne data logger can record directional data which allow the reconstruction of the whole path flown during the homing process. This direction recorder, devised and manufactured by our research group and originally designed to study the pigeons' homing behaviour, has recently been used in studies of wild birds. Our instrument has succesfully been used in investigations of the homing strategies of Cory's shearwaters (Calonectris diomedea) transported and released at sites far from their breeding colony. The direction recorder has also been used in a study of the foraging activity of Brünnich's guillemots (Uria lomvia) breeding at Latrabjarg (NW Iceland); the recorded data have allowed us to reveal aspects of the birds' feeding strategies which were poorly known due to a lack of adequate technology. The recent versions of the data logger, equipped with new devices which can record the flight activity and the diving profile, have open new interesting perspectives for the study of birds' ecology and behaviour.