Dataset Information

Orientation of native versus translocated juvenile lesser spotted eagles (Clanga pomarina) on the first autumn migration.

ABSTRACT: The ontogeny of migration routines used by wild birds remains unresolved. Here we investigated the migratory orientation of juvenile lesser spotted eagles (LSE; Clanga pomarina) based on translocation and satellite tracking. Between 2004 and 2016, 85 second-hatched juveniles (Abels) were reared in captivity for release into the declining German population, including 50 birds that were translocated 940?km from Latvia. In 2009, we tracked 12 translocated juveniles, as well as eight native juveniles and nine native adults, to determine how inexperienced birds come to use strategic migration routes. Native juveniles departed around the same time as the adults and six of eight used the eastern flyway around the Mediterranean, which was used by all adults. In contrast, translocated juveniles departed on average 6?days before native LSEs, and five travelled southward and died in the central Mediterranean region. Consequently, fewer translocated juveniles (4/12) than native juveniles (7/8) reached Africa. We conclude that juvenile LSEs have a much better chance of learning the strategic southeastern flyway if they leave at an appropriate time to connect with experienced elders upon departure. It is not clear why translocated juveniles departed so early. Regardless, by the end of the year, most juveniles had perished, whether they were translocated (10/12) or not (6/8). The small number of surviving translocated juveniles thus still represents a significant increase in the annual productivity of the German LSE population in 2009.

SUBMITTER: Meyburg BU

PROVIDER: S-EPMC5558239 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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Orientation of native versus translocated juvenile lesser spotted eagles (<i>Clanga pomarina</i>) on the first autumn migration.

Meyburg Bernd-U BU Bergmanis Ugis U Langgemach Torsten T Graszynski Kai K Hinz Arno A Börner Ingo I Meyburg Christiane C Vansteelant Wouter M G WMG

The Journal of experimental biology 20170801 Pt 15

The ontogeny of migration routines used by wild birds remains unresolved. Here we investigated the migratory orientation of juvenile lesser spotted eagles (LSE; <i>Clanga pomarina</i>) based on translocation and satellite tracking. Between 2004 and 2016, 85 second-hatched juveniles (Abels) were reared in captivity for release into the declining German population, including 50 birds that were translocated 940 km from Latvia. In 2009, we tracked 12 translocated juveniles, as well as eight native j ...[more]

PMID: 28768749

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Dataset Information

Orientation of native versus translocated juvenile lesser spotted eagles (Clanga pomarina) on the first autumn migration.

Publications

Orientation of native versus translocated juvenile lesser spotted eagles (<i>Clanga pomarina</i>) on the first autumn migration.

Similar Datasets

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