Facing the wind: the aeroecology of vertebrate migrants

For birds and bats the aerosphere is their main habitat. They make use of the airspace for daily activities like mating behaviour, foraging or migration. In this chapter we focus on migration, their large scale movements related to seasonal displacements between breeding and non-breeding ranges. For birds and bats migrating between seasonally favourable habitats across hundreds or thousands of kilometres the conditions of the aerosphere have a substantial impact on energy and time demands, on orientation and navigation, and finally on survival. There are roughly 20 to 40 billion birds and ?? bats undertaking regular season movements within and between continents and across the oceans. Flying within a moving air space they make use of regular seasonal wind fields, like the trade and anti-trade winds, but they also must be aware of irregular events, like heavy storms. In combination with the distribution of their preferred habitats atmospheric conditions guides their flight routes and s