Breeding behaviour of Central European Red Kites: parental sex-dependent differences

Abstract The breeding behaviour of raptors is determined by many characteristics, such as courtship and mating patterns, nest building, foraging, territorial defence activities, clutch incubation, and caring for the young. Here, we study the breeding behaviour of the Red Kite ( Milvus milvus ), a European native bird of prey. From a period between 2018 and 2022, we analysed data for 33 adult Red Kites (14 males and 19 females) during 70 successful breeding episodes in Austria, the Czech Republic, and Slovakia. Using satellite telemetry and in situ observations, we found differences between males and females in the size of the home range, number of nights on the nest, and maximum distances from the nest. We analysed the influence of different factors on movement activity, breeding productivity, and home range size. Females spent significantly more nights on the nest than did males, flew shorter distances from the eyrie, and occupied smaller areas. Red Kites with two or more breeding experiences arrived significantly earlier than did unexperienced Kites in their first breeding attempts. Juveniles departed from the nest sooner than did their parents. Birds with more fledged juveniles occupied smaller home ranges. Our study reveals new knowledge of substantially different breeding behaviours in male and female Central European Red Kites.