Bats are fascinating highly specialised animals. They are the only mammals capable of true flight. With more than 1,200 bat species throughout the world, they count for a quarter of all mammal species. Bats are often considered “keystone species” because they are essential for ecosystems across the world. For example, the majority of bats are insectivorous species and feed exclusively on night-flying insects, including many agricultural pests. Therefore, as main predators of night-flying insects, bats play a significant role in controlling insect populations. About one third of all existing bat species are fruit or nectar feeding, and by doing so pollinate numerous plants and disperse seeds including commercial plants used by us. Unfortunately, often bats do not get the universal recognition they deserve.

With 53 different bats known to occur, Europe has one of the lowest abundance and diversity of bat species compared to other parts of the world. Many European bat species are endangered according to the Red List of Threatened Species (IUCN), and are therefore protected by regulations of Council Directive 92/43/EEC of the European Union on the conservation of natural habitats and of wild fauna and flora, by the Agreement on the Conservation of Bats in Europe, EUROBATS, 1991 or by national legislation.

In Europe, most bats roost or hibernate in trees, buildings or sub terrestrial rooms such as caves, cellars or mines. Within buildings, they prefer attics, planking or areas behind window shutters. Bats are not aggressive, although, like any wild animal, they may bite to defend themselves if handled. Despite the fact that some species of bats are reservoir for lyssaviruses, there is no reason to destroy bat colonies as (i) there is little chance of contact with humans and (ii) pre- and post-exposure prophylaxis is available. Killing of bats is illegal.