Funding for this research was provided by:
National Center of Competence in Research Affective Sciences - Emotions in Individual Behaviour and Social Processes (grant number 31003A_138354)
Text and Data Mining valid from 2018-10-02
Received: 6 February 2018
Accepted: 26 July 2018
First Online: 2 October 2018
: All capture and handling of eurasian hoopoes in Switzerland complied with contemporary laws regulating the treatment of animals in Switzerland and was approved by the appropriate management agencies and ethical committees. All capture and handling of great reed warblers in Bulgaria on was permitted by the Bulgarian Ministry of Environment and Waters (no. 627/30.03.2015).
: Not applicable.
: The authors declare that they have no competing interests
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