Migratory divides highlight intraspecific flexibility in the stopover tactic of black kites

In migrating raptors, route choice can be influenced by multiple factors, including geography, weather conditions, energy constraints, and social interactions. The selected route may in turn be associated with different patterns of stopover habitat use, yet the relationship between the two remains poorly understood. Achieving optimal energy stores is critical for completing long migratory journeys, particularly for birds facing the crossing of major ecological barriers. The black kite Milvus migrans is a migratory raptor with opportunistic feeding habits, which often exploits anthropogenic food sources such as landfills. In this study, we investigated their use by juvenile black kites, according to their migratory flyway. We tracked 43 juveniles using GPS telemetry, from four European breeding areas, using three main flyways to cross the Mediterranean Sea, differing in ecological and geographical characteristics. Route choice primarily depended on natal location, with birds from central European populations spreading over all flyways, and with birds hatched west of 18°E invariably choosing the western one, similar to birds hatched in northern Italy. In contrast, central Italian birds migrated directly southward, crossing the Central Mediterranean. Stopover strategies differed markedly among and within flyways. Along the western route, northern Italian kites made extensive use of landfills in France and Spain, while Czech individuals – despite following partly overlapping routes – stopped mainly in agricultural landscapes. In contrast, birds crossing the Central Mediterranean performed prolonged stopovers (up to 3–4 weeks) in Sicily in semi‐natural agricultural areas, probably exploiting abundant invertebrate prey. Eastern‐route migrants made shorter stops in cultivated areas and wetlands, with minimal landfill use. These findings highlight the behavioural flexibility of black kites, which present a range of foraging strategies, varying between populations and migration routes. Feeding at landfills exposes them to health threats, potentially compromising their fitness and survival across populations nesting far from the original source of contamination.