Honza, Marcel
Požgayová, Milica
Petrželková, Adéla
Procházka, Petr
Funding for this research was provided by:
Czech Science Foundation (This work was supported by the Czech Science Foundation (grant number 17-12262S).)
Article History
Received: 12 February 2018
Revised: 7 June 2018
Accepted: 14 June 2018
First Online: 2 July 2018
Compliance with ethical standards
:
: The authors declare that they have no conflict of interest.
: To assess possible ethical impact of our experimental manipulation, we compared several aspects of bird behaviour related to food intake or conspicuousness to potential predators on the video recordings with and without the HAV and control playback, respectively. Cuckoo chicks received similar volumes of food per hour both before and after the playback (mean ± SD; cuckoo HAV, before: 15.10 ± 7.46, after: 15.18 ± 7.66, paired t test t = − 0.05, df = 28, P = 0.963; control background noise, before: 13.53 ± 6.19, after: 13.52 ± 7.78, paired t test t = 0.01, df = 14, P = 0.994). Hence, a short-term increase in food volume or provisioning rate in response to the HAV playback should not have had negative effects either on the cuckoo chicks or great reed warbler hosts. Predation rates of cuckoo chicks did not significantly differ among the groups of nests subjected to the playback of cuckoo HAV (10%, N = 26), control playback (27%, N = 15) or no playback (17%, N = 24; 2 × 3 Fisher exact probability test: P = 0.491). None of the nests were deserted due to the experimental or control treatment or any other reasons.This study was carried out with the permission of the regional nature conservation authorities (permit numbers JMK: 115874/2013 and 38506/2016; MUHOCJ: 41433/2012/OŽP, 34437/2014/OŽP, and 14306/2016/OŽP). The fieldwork adhered to the animal care protocol (experimental project numbers 039/2011 AV ČR and 3030/ENV/17-169/630/17) and to the Czech Law on the Protection of Animals against Mistreatment (licence numbers CZ 01272 and CZ 01284).