All released bearded vultures, some Eurasian black vultures, griffon vultures, and Egyptian vultures are tagged with a GPS transmitter. This allows to follow the movement of the birds and see where they are flying. It is also a very valuable tool to keep control on the birds and their health. Some of the tracks are available to the public.
Bearded Vultures marked on Corsica by the Parc naturel régional de Corse, France:
Egyptian Vultures marked by the project "The return of the Neophron" in Greece and Bulgaria:
Eurasian Black Vulture Peñalara and Escobalón marked by the Spanish WWF in Madrid - Spain