Factors influencing the post-fledging period and timing of dispersal in Bobelli's eagles Hieratus fasciatus in southwestern Spain

We studied factors influencing the length of the post-fledging period (from fledging to the start of dispersal) of Bonelli’s Eagle (Hieraaetusfasciatus) nestlings in soutlswestern Spain, using 13 nestlings equipped with radiotransmitters. The age at fledging was negatively correlated with hatching d...

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Bibliographic Details
Authors: Mínguez, Eduardo, Angulo, Elena, Siebering, Vivian
Format: article
Publication Date:2001
Country:España
Institution:Consejo Superior de Investigaciones Científicas (CSIC)
Repository:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/45539
Online Access:http://hdl.handle.net/10261/45539
Access Level:Open access
Keyword:Bonelli´s eagle
Hieratus fasciatus
juvenile dispersal behavior
post-fledging period
Red-legged partridge
wild rabbits
Description
Summary:We studied factors influencing the length of the post-fledging period (from fledging to the start of dispersal) of Bonelli’s Eagle (Hieraaetusfasciatus) nestlings in soutlswestern Spain, using 13 nestlings equipped with radiotransmitters. The age at fledging was negatively correlated with hatching date, but the duration of the post-fledging period was directly related to hatching date. This pattern could be explained by seasonal changes in prey abundance, especially that of wild rabbits (Oryctolagus cuniculus). Young in­ creased their mobility throughout the post-fledging period, with a significant increase in the middle of the period. Dispersal began suddenly. The direction of dispersal was random, but most of the areas first used were located <25 km away and at lower altitudes than the nesting area