Migration and wintering of adult European honey buzzards (Pernis apivorus) breeding in Germany, as revealed by satellite telemetry

Twelve adult European honey buzzards (Pernis apivorus) were tracked for up to five years. The females left the breeding area approximately eight days earlier than the males. Ten of the birds appeared to die during the telemetry period. In autumn, all of the birds migrated to West Africa, reaching as far south as the Republic of the Congo via France and Spain. In most cases (13 out of 20 migrations involving nine birds), they crossed the western third of the Pyrenees. Most of them used the Strait of Gibraltar to reach Africa (16 migrations involving 10 birds), but in some cases (three migrations involving two birds) they flew long distances over the Mediterranean sea instead. The routes of individual birds varied from year to year. In spring, the birds generally migrated farther east than in autumn. Three honey buzzards wintered in Nigeria, two in Liberia and one in each of Cameroon, Gabon and the Republic of the Congo. The distances travelled between the breeding grounds and wintering areas ranged from 6,128 km to Liberia to 8,645 km to the Republic of the Congo. The autumn migration lasted between 36 and 99 days, while the spring migration lasted between 23 and 55 days. This depended on the length of the migration route, the duration of stopovers and other factors. Birds travelled up to 600 km per day, reaching a maximum speed of 109 km/h. Winter site fidelity over consecutive years was recorded for four individuals over up to four winters. The home ranges of two wintering honey buzzards were calculated from up to 97 GPS fixes. These birds had small winter home ranges of 1.55 and 3.40 km² (MCP95), and 4.43 and 7.44 km2 (KDE95), respectively.