greater mouse-eared bat

greater mouse-eared bat is a large vespertilionid bat species found across much of Europe and parts of Western Asia. It is one of the largest mouse-eared bat species on the continent, known for its robust size and distinctive foraging behavior. The species plays a significant ecological role and has been the subject of extensive study, particularly following its notable disappearance and subsequent recolonization in the United Kingdom.

Description

The greater mouse-eared bat is characterized by its substantial size, with a wingspan often exceeding 40 centimeters and a body weight typically between 25 and 40 grams. Its fur is a pale grey-brown on the dorsal side with a noticeably lighter, almost whitish underside. The ears are long and broad, a hallmark of the Myotis genus, and the tragus is pointed. Its flight membranes are a dark grey-brown. Morphologically, it is often confused with the closely related lesser mouse-eared bat, though it is generally larger and possesses distinct cranial and dental characteristics. Key identification features include its robust skull and the shape of its upper premolar.

Distribution and habitat

This species has a wide but patchy distribution across southern and central Europe, from the Iberian Peninsula eastward through France, Germany, Italy, the Balkans, and into Turkey and the Levant. Its northern range extends to southern Poland and the Netherlands. It is strongly associated with karst landscapes and typically roosts in large, warm caves or underground structures such as cellars, fortifications, and abandoned mines during summer and winter. For foraging, it requires a mosaic of open landscapes, including deciduous woodlands, parklands, pastures, and scrub, often near its roost sites. Historical records indicate it was once present in southern England, but it was declared extinct there in the 1990s before a solitary male was discovered in West Sussex in 2002.

Behavior and ecology

The greater mouse-eared bat is a nocturnal hunter, emerging at dusk to forage primarily by gleaning large ground-dwelling arthropods from the surface. Its diet consists overwhelmingly of ground beetles and other Coleoptera, as well as large Orthoptera like crickets. It uses passive listening to detect the rustling sounds of prey, supplemented by low-frequency echolocation calls. Maternity colonies, which can number several hundred to over a thousand individuals, form in warm cave roofs in spring. Hibernation occurs in cold, humid caves or tunnels from October to March, often in large clusters. A single pup is born annually in early summer. Known predators include various owls, such as the barn owl, and occasionally mustelids like the stone marten.

Conservation status

The greater mouse-eared bat is classified as Least Concern on the IUCN Red List due to its large geographic range and presumed large population. However, many regional populations are declining and it is protected under the Bonn Convention and the Bern Convention. Within the European Union, it is listed under Annexes II and IV of the Habitats Directive, requiring the designation of Special Areas of Conservation. Major threats include disturbance and destruction of underground roosts, agricultural intensification reducing prey availability, and the use of toxic wood preservatives in roof timbers. Conservation efforts are coordinated through the EUROBATS agreement.

Relationship to humans

This species has a long history of interaction with human structures, frequently utilizing old buildings, castles, and church attics as alternative roosts. It was at the center of a significant conservation story in Britain, where it was the first mammal declared extinct in the country since the wolf, only to be rediscovered later. The greater mouse-eared bat is a popular species for bat research and public engagement due to its size and distinctive ecology. It is also featured in monitoring programs like the National Bat Monitoring Programme run by the Bat Conservation Trust. While sometimes considered a nuisance in attic spaces, it is legally protected across its range, and its presence can influence planning decisions for development and forestry.

Category:Bats of Europe Category:Mammals of Asia Category:Myotis