Steppe Eagle migration strategies - revealed by satellite telemetry.

Meyburg, B.-U., C. Meyburg & P. Paillat:

Brit. Birds 105: 506-519 (2012)

ZUSAMMENFASSUNG

Sixteen Steppe Eagles Aquila nipalensis were fitted with satellite transmitters during migration or on their wintering grounds (15 in Saudi Arabia, one in South Africa). From these 16 birds, a total of 3,734 location co-ordinates were received. Adult and immature Steppe Eagle migration strategies were markedly different in terms of timing (adults returned to breeding territories in southern Russia and Kazakhstan in late March and early April, whereas immatures arrived in mid May) but not in terms of route and wintering area. Immatures remained on the wintering grounds for substantially longer than adults, typically for about six months. An adult took almost eight weeks to cover 9,543 km from Botswana to Kazakhstan, averaging 177 km daily. The longest mean daily flight distance among all tracked individuals was approximately 355 km. In 1998, an adult male was recorded through a complete annual cycle; it spent 31.5% of the period in the wintering area in Ethiopia and Sudan, 41.9% in the breeding area in Kazakhstan, and 26.6% on migration.