Funding for this research was provided by:
CIGA (20184208, 20164209)
IGA FZP (20164218)
Text and Data Mining valid from 2019-03-22
Received: 28 September 2018
Accepted: 4 March 2019
First Online: 22 March 2019
Ethics approval and consent to participate
: The study was conducted in accordance with the current laws of the Czech Republic, where it was performed under the ringing licence (1082) of the Czech Ornithological Society.
: The authors declare that they have no competing interests.
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