Greater Mouse-eared Bat (Myotis myotis)


Class: Mammalia
Order: Chiroptera
Family:    Vespertilionidae
Size:    Length: 2.5 to 3 inches  (6.5 to 8 cm) Wingspan: 14 to 17 inches  (35.5 to 45 cm)
Weight: 0.7 to 1.6 ounces (20 to 45 grams)
Diet: Mostly moths and beetles
Distribution: Central and Eastern Europe
Young:  1
Animal Predators:  Snakes, opossums and owls
IUCN Status: Lower Risk, Near Threatened
Terms: Young: Pup  Group: Colony
Lifespan: Up to 22 years in the wild and up to 2 years in captivity 



·       In 1991, greater mouse-eared bats were declared extinct in Britain.

·       The greater mouse-eared bat is one of the largest bats in Europe, and females are larger than males.

·       Bats are the only mammals capable of true and sustained flight.

·       Although “blind as a bat” is a common saying, it is inaccurate, because all bats have vision. 



Greater mouse-eared bats have grey-brown fur on their back and head, and white on their undersides. Their face is bare, with pink skin and small eyes. Their ears are large and rounded. 



These bats were common throughout Europe until the 1950s. They are now practically extinct throughout northwestern Europe, although new roosts have been created in Germany and the Netherlands. During the day, mouse-eared bats sleep, usually in a cave, or an abandoned building or mine. In the winter they fly up to 6 miles (10 km), to a winter roost where they hibernate.


Feeding Habits

After dark, they fly off in search of insects such as moths and beetles to feed on. Mouse-eared bats detect their prey using echolocation. In other words, they emit a high-pitched sound, and depending on the sound that bounces back, they can tell whether there are any objects or prey nearby, as well as the size, distance and movement. They then open their wings to trap the prey. Sometimes mouse-eared bats search for beetles on the ground. 



Young mouse-eared bats are usually born between April and July. Newborns are born without fur or sight, and they cling to their mothers. 



Mouse-eared bats hang upside down by their feet from rafters or from the cave roof. Pregnant females form large colonies, and once they have given birth, leave the babies with two or three females while they go out to hunt. 



The main reason for the decline of this bat species is a loss of habitat due to their caves being disturbed by spelunking activity, tourism, garbage disposal, and occurrences of vandalism. They are also highly susceptible to becoming poisoned by insecticides, and the insecticides further destroy their way of life by killing their prey. There are nearly 1,000 different species of bats, living on every continent in the world. In Europe, bats are protected under the Wildlife Order of 1985. This order is very strict—it is not only illegal to intentionally kill or injure a bat, but disturbing a roosting bat, handling a bat, or possessing a bat (alive or dead) are also against the law. Even photographing a bat is forbidden without a license. The public however, is allowed to care for an injured bat as long as the bat is set free once recuperated.



Mouse-Eared Bat Wildlife Fact File, IM Pub, US