Dispersal and philopatry in Central European Red Kites Milvus milvus

In a study of the extent and timing of Red Kite Milvus milvus dispersal movements from Central Europe (Austria, the Czech Republic and Slovakia) using GPS telemetry, we found support for the hypothesis that Red Kite dispersal, including migration behaviour, is dependent on both age and sex. Examination of the tendency to stay in, or return to, a particular area in Red Kites indicated that, while part of the population remained in the natal area, most migrated to overwintering sites across a broad belt of southern European sites stretching from the Iberian Peninsula to the Balkans. Red Kites first bred at 2 years old, i.e. in their 3rd calendar year. Migration routes were significantly longer in females than males, while natal philopatry was significantly higher in males than females. The lengths of single-year migration routes decreased significantly over consecutive years, and breeding philopatry increased significantly in cases where previous breeding was successful.