SATELLITE-TRACKING OF THE ANNUAL MIGRATIO N OF A WHITE-STORK CICONIA-CICONIA AND DISCUSSION OF THE ORIENTATION MECHANISMS OF HOMEWARD MIGRATION

In a female White Stork the complete migration cycle could be tracked by satellite from the nesting site to the wintering grounds in the Sud an and Tanzania and back to the nest. The migration route extended ove r 16 000 km, autumn migration lasted 100 days, homeward migration 70 d ays, wintering 58 and 41 days in northeastern and southeastern Africa, respectively. The maximum daily route was about 350 km. Up to Turkey the bird migrated together with its male. Homeward migration was perfo rmed within a relatively narrow corridor in which autumn migration roo k place, but in detail the routes of the two migratory seasons showed substantial differences. These data together with those from some rapt ors in which complete annual migration cycles could be tracked indicat e that homeward migration is based on navigation (vector navigation an d/or true navigation) rather than on route reversal.