The European White Stork, EWS, (Ciconia ciconia) has an extensive European breeding distribution. However, there have been significant demographic changes since the 1930’s, with country-specific extinctions throughout the western distribution since the mid 1940’s. Generally this has been attributed to habitat alteration and climate conditions. Reintroduction programmes in Switzerland, France, Germany, Belgium, the Netherlands and Sweden, have returned natural breeding populations to historical ranges. Significant concerns have been raised about the geographic origins of introduced storks, and the effect this may have on individual biology, particularly breeding success. Translocation between east and west populations may also have a significant impact upon overall genetic structure. Additionally, supplementary feeding associated with reintroduction programmes, and the prevalence of human waste disposal sites as alternate foraging habitats have been linked to changes in migration strategy. At present there’s no scientific evidence for genes driving differences in migratory pathways (East versus West) in EWS. However, all previous analyses were based on a limited set of neutral markers. Within this study we investigated whether genes that recently have be linked to migratory behavior in other species, explain part of the observed migratory variation in EWS. Besides assessing (allele frequency) differences/changes at a population/location level, we analyze individual stork with known migration profiles. Accordingly, the principal objectives of the project are to 1) characterise genetic variability of C. ciconia for candidate migratory genes at the population level, and 2) link individual genetic and (migration) behavioural characteristics (mainly for bird sampled in Switzerland and Spain).