The Greater mouse-eared bat is a large European bat with a long, broad muzzle and big, long ears. Its body's dorsal side is brown to reddish-brown, while the ventral side is dirty white, or beige. The tragus forms half of the ear, with a small black tip in most individuals. Wing membranes are brownish in color. Females of this species are slightly larger than males.
Greater mouse-eared bats can be found in most European countries except Denmark, Latvia, Estonia, Finland, and the Scandinavian Peninsula. They are also found on many Mediterranean islands, such as Sicily, Malta, and the Gymnesian Islands. In the Middle East, these bats occur in Turkey, Israel, Syria, Jordan, and Lebanon. They typically forage in open deciduous woodlands, forest edges, and pastures. Roosting sites are located underground throughout the year where the bats also hibernate, In Northern Europe, they may also roost in attics and lofts of buildings.
Greater mouse-eared bats are highly social creatures and on Mediterranean islands such as Mallorca, their colonies usually have up to 500 individuals. In continental Europe, they may form colonies of over 4.500 bats. Greater mouse-eared bats may also roost with other bats, such as long-fingered bats and Common bent-wing bats. Like its relatives, the Greater mouse-eared bat is a nocturnal forager; however, unlike many bats, it does not capture its prey by using echolocation in flight. Instead, it gleans it from the ground, locating prey passively by listening for the noises produced by insects. As a result, it uses echolocation only for spatial orientation, even if it emits ultrasound calls when approaching prey. In mainland Europe, Greater mouse-eared bats may perform annual dispersions of up to 200 km in spring, however, usually, they travel only 10 km or so.
Greater mouse-eared bats breed in autumn and females give birth from May to June. Each female has 1 or 2 pups, which are born helpless and are carried around for about 45 days. During this period, females form nursery colonies from which males are excluded. Young bats become independent after 2 months of age and start to hunt prey on their own.
Great mouse-eared bats suffer from the loss of roosting sites in underground habitats and poisoning by pesticides while foraging in cultivated areas.
The IUCN Red List and other sources don’t provide the number of the Greater mouse-eared bat total population size. Currently, this species is classified as Least Concern (LC) on the IUCN Red List and its numbers today are stable.