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Résumé :
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The comprehensive analysis of more than 5000 data from field work (netting, ringing, observations), literature and museum specimens shows distinctive migration patterns and the existence of two separate wintering areas of European Golden Orioles in Africa. Autumn migration continues until December and spring migration starts in February. Winter distribution between mid of December and February covers a smaller area north of the rainforest in Cameroun and the Central African Republic and a larger one south of 5degree S. In these areas periodical rainfalls allow for the development of moist deciduous woodlands. There are no reliable wintering records of West Africa yet. O. oriolus in Africa prefers habitats like savanna woodlands, forest-savanna-mosaic, forest vegetation of Guinea-Zones, riverine and gallery forests. Only rarely birds have been recorded from rainforests when on migration. Analysis of migration phenology shows that the latest birds reach and leave Africa along the Red Sea Coast crossing the Arabian Peninsula. In NE-Africa differential migration of males versus females/young birds is documented. This phenomenon seems to coincide with the period of nocturnal migration and is confined to areas north of about 5degree S. South of it, migrations strongly correlate with periodical rainfalls and orioles visit seasonal habitats in the state of maximum foliation and food supplies.
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