Spring bird migration movements

European bee-eaters arrive later in spring compared to the other species, whereas White storks are the earlier spring visitors among the modelled species. From the maps, we can see that migrant White storks, Barn swallows and Black kites arriving in Europe from the East tend to arrive later into their breeding grounds compared to birds following the western European flyway. This is probably related to the greater distance that these birds have to cover, since many birds breeding in central and eastern Europe winter in southern Africa, in contrast to birds breeding in western Europe, which mainly winter in the Sahel. This could make these birds more vulnerable to climate variations since their behavioural responses may not be enough to avoid inharmonious arrival dates and spring events.