Plecotus austriacusgray big-eared bat

Geographic Range

The grey long-eared bat is found in suitable habitat across Eurasia and northern Africa. (Wilson and Reeder, 1993)

Habitat

P. austriacus can be found dwelling in caves, tall tropical flowers, old bird nests, under rocks, or more likely in tunnels and buildings with many crevices. They are rarely found deep in caves but spend most of the winter at the entrances. They also tend to return to the same roosting site year after year. P. austriacus can be found mostly in villages where there is an abundance of trees and warm old buildings. (Altringham,1996)

Physical Description

This species strongly resembles another species in its genus, P. auritus, except for color. The fur of the P. austriacus is more grey than brown. Its face is also slightly larger. It has very broad wings and long ears measuring about 40 mm in length. Its ears are folded and tucked underneath its wings during the winter months of hibernation. (Nowak 1997)

  • Range mass
    5 to 20 g
    0.18 to 0.70 oz
  • Average mass
    10 g
    0.35 oz
  • Range length
    45 to 70 mm
    1.77 to 2.76 in
  • Average length
    58 mm
    2.28 in
  • Range wingspan
    35 to 52 mm
    1.38 to 2.05 in
  • Average wingspan
    44 mm
    1.73 in

Reproduction

Members of this species practice sperm storage and delayed fertilization. The male and female copulate in the fall, whereupon sperm is stored in the uterus of the female. Ovulation and fertilization occur in the following spring. The young are born early in summer in order to have enough time to build enough fat from weaning to survive the winter. The female has only one reproductive cycle per year. During the developmental stage, the mother and offspring remain in their roosting sites for July and August. (Swift 1998 and Wilson 1997)

  • Range number of offspring
    1 to 4
  • Range gestation period
    40 to 100 days
  • Range age at sexual or reproductive maturity (female)
    2 to 3 years
  • Range age at sexual or reproductive maturity (male)
    1 to 2 years

Lifespan/Longevity

Behavior

Communication and Perception

Food Habits

Like most vespertilionids bats, these bats usually capture insects while flying by using a pouch formed by their tail membrane. Because they only fly after dark, P. austriacus rely heavily on echolocation in order to capture prey. Insects are usually the preferred dish although there have been cases where a bat in captivity was given only a small lizard and ate it. (Leen 1969)

  • Animal Foods
  • reptiles
  • insects

Predation

Plecotus austriacus can stay in flight while hunting its prey and get back to its roosting site with no trouble from predators. The only effective predator on this bat is usually humans. Predation by birds is usually opportunistic. Predation by domestic cats is a threat to those bats dwelling in attics and rafters of old homes. (Nowak 1997)

Economic Importance for Humans: Positive

Because this species is an insectivore, it can be said that they control insect populations in their geographic range.

  • Positive Impacts
  • controls pest population

Economic Importance for Humans: Negative

The only documented problem found with P. austriacus is that it tends to hibernate in buildings frequented by humans. It can be seen as a household pest because its droppings in attics may cover furniture and other possessions stored there. Contrary to popular belief, bats are not dirty but groom themselves often. Another potential problem is that bats carry rabies. In fact, one is much more likely to get rabies from an unvaccinated dog than from a bat.

  • Negative Impacts
  • household pest

Conservation Status

In Britain, the grey long-eared bat is protected by the Wildlife and Countryside Act of 1981 which makes it illegal to capture, injure, kill, or disturb a bat.

Other ways to conserve this population are to preserve old farm buildings and deciduous woodlands.

Other Comments

Females are heterothermic during early pregnancy but become homeothermic from mid-late pregnancy to birth. (Altringham 1996)

Because this species dwells mostly in man-made buildings, it is susceptible to different types of chemical poisons found in the timber used in architecture.

Contributors

Renee Boji (author), University of Michigan-Ann Arbor, Kate Teeter (editor), University of Michigan-Ann Arbor.

Glossary

Ethiopian

living in sub-Saharan Africa (south of 30 degrees north) and Madagascar.

World Map

Palearctic

living in the northern part of the Old World. In otherwords, Europe and Asia and northern Africa.

World Map

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

carnivore

an animal that mainly eats meat

chemical

uses smells or other chemicals to communicate

colonial

used loosely to describe any group of organisms living together or in close proximity to each other - for example nesting shorebirds that live in large colonies. More specifically refers to a group of organisms in which members act as specialized subunits (a continuous, modular society) - as in clonal organisms.

delayed fertilization

a substantial delay (longer than the minimum time required for sperm to travel to the egg) takes place between copulation and fertilization, used to describe female sperm storage.

endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

forest

forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.

insectivore

An animal that eats mainly insects or spiders.

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

nocturnal

active during the night

oriental

found in the oriental region of the world. In other words, India and southeast Asia.

World Map

seasonal breeding

breeding is confined to a particular season

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

solitary

lives alone

sperm-storing

mature spermatozoa are stored by females following copulation. Male sperm storage also occurs, as sperm are retained in the male epididymes (in mammals) for a period that can, in some cases, extend over several weeks or more, but here we use the term to refer only to sperm storage by females.

suburban

living in residential areas on the outskirts of large cities or towns.

tactile

uses touch to communicate

temperate

that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).

terrestrial

Living on the ground.

urban

living in cities and large towns, landscapes dominated by human structures and activity.

viviparous

reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.

References

Altringham, J. 1996. Bats: Biology and Behavior. Oxford: Oxford University Press.

Leen, N. 1969. The World of Bats. New York: Holt, Rhinehart and Winston.

Nowak, R. 1997. "Walker's Mammals of the World" (On-line). Accessed October 8, 2001 at http://www.press.jhu.edu/books/walker/chiroptera.html.

Swift, S. 1998. Long-Eared Bats. Cambridge: University Press.

Wilson, D., D. Reeder. 1993. Mammal Species of the World. Washington, DC: Smithsonian Institution Press.

Wilson, D. 1997. Bats in Question. Washington: Smithsonian Institution Press.