Supplementary feeding experiment
Supplementary feeding started before or during incubation and ended around fledging at a brood age of c. 52 days. We mounted feeding platforms in the territory of selected red kite breeding pairs in open fields near the nest (distance to the nest: 20 – 200 m), where they were easily accessible to the red kites. Platforms consisted of a 0.6 m x 0.6 m wooden board on a 2 m post. Every second day, we placed five dead individuals of day-old chickens per adult and per nestling on the platforms when nestlings were ≤ 9 days old, and ten chickens per nestling when they were > 9 days old (for details on the supplementary feeding experiment, see Nägeli et al. 2022; Scherler et al. 2023b).