Document is current

Article History

Received: 1 December 2023

Revised: 29 May 2024

Accepted: 6 June 2024

First Online: 21 June 2024

Declarations

:

: Trapping, ringing and blood sampling of birds were conducted according to protocols established during the long-term monitoring of the study population of collared flycatchers since the early 1980s. Adult birds were trapped with spring traps attached to the nest box entrance when the chicks were already endothermic and did not require brooding. The birds were released immediately after measurements and resumed breeding activities soon thereafter. During the cross-fostering, nestlings were transferred in soft cotton bags placed in boxes heated with reusable pocket warmer packs. The cross-fostering apparently had no adverse effect on the nestlings, because fledging success in the experimental nests was similar to that in unmanipulated nests. To reduce disturbance, we used external video cameras set up approx. 10–15 m away from the recorded nest box. The nestlings continued to receive food shortly after the start of the video recording (<i>X</i> ± SD = 109 ± 82 s). The use of animals adheres to the guidelines set forth by the Animal Behavior Society/Association for the Study of Animal Behaviour (). This study received prior approval from the National Scientific Ethical Committee on Animal Experimentation and the Department of Environment and Nature Protection of the Hungarian Government Office (case numbers PE/KTF/11978- 6/2015, PEI/001/1054–6/2015, PE-06/KTF/3331–4/2018, PE/EA/77–8/2018).

: The authors declare no competing interests.