Greater Mouse Eared Bat

Fossil evidence shows the separation of M. myotis from M. blythii occurred during the Pleistocene.

Perception Channels: tactile ; chemical

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

Positive Impacts: controls pest population

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 )

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 )

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

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.

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

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)

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); sexual ; 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