Many bat species hunt and migrate at great altitudes. The range of the open sky is a new interest area as a habitat relevant to a large variety of species. Christian Voigt and colleagues from the Leibniz Institute for Zoo and Wildlife Research (IZW) in Berlin have collated the current scientific knowledge on potential hazards to bats flying at high altitudes. In their recent article published in BioScience the authors synthesise threats facing bats in the troposphere and provide recommendations for potential protective measures to ensure the persistence of bats and other high-flying animals.