Migration strategies revealed by satellite tracking among descendants of a population of European white stork (Ciconia ciconia) reintroduced to Belgium

摘要

Migration in the European white stork (Ciconia ciconia) has historically described a predictable annual cycle. The white stork is extensively distributed across continental Europe, which diverges to eastern and western wintering flyways. Within the western European population, some ring recovery and anecdotal information suggests that birds are giving up their traditional wintering grounds in the Sahel and are remaining in alternative sites in the Iberian Peninsula. Here we report on long-term satellite tracking of juvenile and adult stork collected between 2000 and 2011, whose natal site is in Belgium in the northern range of the western migration path. We identified three distinct migration patterns, two of which diverged from traditional expectations. Juvenile birds showed unique migration profiles both individually across migration cycles and when compared to one another, whereas adults showed consistent migrations but failed to migrate to Africa in any of the years surveyed. Stopover and wintering locations within Iberia were strongly associated with refuse sites or modified agricultural land. Overall, non-traditional migration movements appeared to be most strongly linked to artificial food sources rather than alternate drivers such as climate or habitat.