Morphological differences of the flight apparatus of Black and White Storks

As stork species living and breeding in the temperate latitudes of the Palearctic, Black and White Storks show a distinctive migratory behavior towards the African continent. Although both species are thermal updraft dependent migratory birds and largely circumvent the Mediterranean Sea, particularly in the case of the Black Stork, Mediterranean crossings have been documented repeatedly. Additionally, transmitter data of Black and White Storks show that Black Storks cross the Mediterranean much more frequently than their close relatives. In my thesis I examined, wether there is evidence for morphological differences in the flight apparatus of Black and White Stork, which could further explain these differences in the migratory behavior of both species. Therefore, I measured the flight feathers, rectrices and alula feathers on skins, and sternum, furcula, coracoid, humerus, and ulna on skeletal specimens of Black and White Storks.