This bat preys on larger insects, mainly beetles, which they hunt for about four to five hours after emerging late in the evening. They are known to forage on the ground for some of their insect prey. Male greater mouse-eared bats are polygamous, and may have a harem of up to five females. The females form large maternity roosts in attics or caves and give birth to one offspring, usually in June. When they leave to feed, females leave their babies in a crèche and there are often several females left to guard the roost. The young bats can fly after three weeks, and become sexually mature at three months.

The greater mouse-eared bat is one of the larger European bats and has become extinct in England. Its fur is a medium-brown colour on the upper body, and greyish-white underneath. It has large ears with a very prominent tragus, the organ which is part of the bat's echolocation system.

Myotis myotis is a western Palaearctic species; it occurs in western, central and southern Europe (with individual records from southern England and southern Sweden) and in Asia Minor and in the Levant.

This species is found throughout Eurasia and part of northern Africa. It has gone extinct in the United Kingdom after 1990.

Biogeographic Regions: palearctic (Native ); oriental (Native )

This species is found across central Europe and in scattered populations across southern Europe, but is threatened with extinction across the whole of its range. It used to be found in Dorset and Sussex, but was officially declared extinct in Britain in 1990.

M. myotis are relatively large bats, with long ears, overall length 6.5-8.0 cm, broad wingspan 36.5-45.0 cm, and forearm length about 5.7 cm. Adult body weights are about 20-45 g. Females are larger than males.

M. myotis are very similar to M. blythii phisically.

Range mass: 20 to 45 g.

Range length: 6.5 to 8.0 cm.

Range wingspan: 36.5 to 45.0 cm.

Other Physical Features: endothermic ; bilateral symmetry

Habitat and Ecology

Systems

• Terrestrial

M. myotis primarily inhabit caves and buildings such as churches and castles. They also dwell in relatively open, lightly wooded forests.

Habitat Regions: temperate ; terrestrial

Terrestrial Biomes: forest

Other Habitat Features: urban ; suburban

Greater mouse-eared bats are usually found around human settlements. They probably used caves as roosting sites, and today they hibernate in both caves and mines. They hunt in forests and adjoining cultivated areas.

These bats are opportunistic predators. They primarily feed on ground beetles such as carabids (Carabidae), but also prey on large moths and grass beetles whenever possible. M. myotis prefer feeding in open woodland with ground cover of few grasses. They may have evolved to catch ground beetles on the soil surface. However, they may select alternative preys if primary sources do not meet their requirements. They consume around 25-50% of body weight nightly.

Animal Foods: insects

Primary Diet: carnivore (Insectivore )

Animal / parasite / ectoparasite
Basilia nana ectoparasitises Myotis myotis
Other: minor host/prey

Animal / parasite / ectoparasite
Nycteribia kolenatii ectoparasitises Myotis myotis
Other: minor host/prey

Animal / parasite / ectoparasite
Phthiridium biarticulata ectoparasitises Myotis myotis

The main factor that causes decline of M. myotis populations may be human disturbance. People both use agrochemicals which poison bats, or disturb caves that causes death at roosts. In addition, large scale agricultural change has reduced areas of open ground and increase grassland, and this also results in reductions in the number of bats.

Known Predators:

• humans (Homo sapiens)

Myotis myotis is prey of:
Homo sapiens

This list may not be complete but is based on published studies.

Myotis myotis preys on:
Insecta

This list may not be complete but is based on published studies.

Life span in Myotis is usually 6 to 7 years, but M. myotis were recorded as 13 years old in the United Kingdom. In wild, some may survive up to 22 years.

Range lifespan

Status: wild: 22 (high) years.

Average lifespan

Status: wild: 13 years.

Average lifespan

Status: wild: 18.0 years.

Maximum longevity: 22 years (wild)

Mating System: polygynandrous (promiscuous)

M. myotis are early breeders. Ovulation and fertilization may take place during February mostly, or in October if birth occurs in winter. Gestation period is about 60-70 days. Births take place mostly in April to June, but some were observed in winter. After birth, young M. myotis remain fixed on their mothers for about 2 weeks. Female M. myotis mate again as soon as the young become independent. Females store sperm in the uterus, but eggs are not fertilized until the next spring.

Babies are born with claws on their hind feet and milk teeth. They are blind at birth. The young become independent after 2 months and start to feed on insects. They must accumulate sufficient fat reserves for hibernation.

Breeding season: Late spring to summer.

Range number of offspring: 1 to 2.

Average number of offspring: 1.

Range gestation period: 60 to 70 days.

Average weaning age: 60 days.

Key Reproductive Features: seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); viviparous ; sperm-storing

Average birth mass: 5.9 g.

Average number of offspring: 1.

Average age at sexual or reproductive maturity (male)

Sex: male: 502 days.

Average age at sexual or reproductive maturity (female)

Sex: female: 502 days.

Parental Investment: altricial

Internal magnetic compass recalibrates: greater mouse-eared bat
 

The internal magnetic compass of greater mouse-eared bats can be calibrated with directional reference from the setting sun.

     
  "Recent evidence suggests that bats can detect the geomagnetic field, but  the way in which this is used by them for navigation  to a home roost remains unresolved. The geomagnetic  field may be used by animals both to indicate direction and to locate  position. In birds, directional information appears  to be derived from an interaction of the magnetic field with either the  sun or the stars, with some evidence suggesting  that sunset/sunrise provides the primary directional reference by which a  magnetic compass is calibrated daily. We  demonstrate that homing greater mouse-eared bats (Myotis myotis)  calibrate a magnetic compass with sunset cues by testing their homing  response after exposure to an altered magnetic field  at and after sunset. Magnetic manipulation at  sunset resulted in a counterclockwise shift in orientation compared with  controls,  consistent with sunset calibration of the magnetic  field, whereas magnetic manipulation after sunset resulted in no change  in orientation. Unlike in birds, however, the  pattern of polarization was not necessary for the calibration. For  animals that  occupy ecological niches where the sunset is rarely  observed, this is a surprising finding. Yet it may indicate the primacy  of the sun as an absolute geographical reference  not only for birds but also within other vertebrate taxa." (Holland et al. 2010:6941)
  Learn more about this functional adaptation.

The following is a representative barcode sequence, the centroid of all available sequences for this species.


No available public DNA sequences.

Download FASTA File

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 15
Specimens with Barcodes: 27
Species With Barcodes: 1

IUCN status category: Low risk, near threatened.

Red book: vulnerable.

Numbers have declined fast recently and the species has gone extinct in northwestern Europe.

US Federal List: no special status

CITES: no special status

IUCN Red List of Threatened Species: least concern

Classified as Extinct in the UK. Listed under Appendix II of the Bonn Convention, Annex II of the Berne Convention, Annex II & IV of the EC Habitats Directive and Schedule 5 of the Wildlife and Countryside Act (as amended).

Population

Population Trend

Major Threats

The greater mouse-eared bat was only discovered in Britain in 1958, and the last specimen was recorded in 1990. It is not clear why it became extinct in Britain although it is known never to have been a common animal. One possibility is that the nursery roosts of this bat were subject to disturbance and destruction. They are extremely susceptible to the chemicals used to treat timber roofs (as are all bats), and it is possible that this process destroyed their maternity roosts.

Conservation Actions

As this bat has been extinct in the UK for some years, work on conserving it has concentrated on preparing a plan should it ever re-colonise the British Isles. There are regular surveys of its former sites, and, as a commitment to this species, the greater mouse-eared bat is still listed in the UK Biodiversity Action Plans (UK BAPs).

Positive Impacts: controls pest population