The brown long-eared bat or common long-eared bat (''Plecotus auritus'') is a small

Eurasian Eurasia (, ) is the largest continental area on Earth, comprising all of Europe and Asia. Primarily in the Northern and Eastern Hemispheres, it spans from the British Isles and the Iberian Peninsula in the west to the Japanese archipela ...

insectivorous A robber fly eating a hoverfly An insectivore is a carnivorous animal or plant that eats insects. An alternative term is entomophage, which can also refer to the human practice of eating insects. The first vertebrate insectivores we ...

bat Bats are mammals of the order Chiroptera.''cheir'', "hand" and πτερόν''pteron'', "wing". With their forelimbs adapted as wings, they are the only mammals capable of true and sustained flight. Bats are more agile in flight than most bi ...

. It has distinctive ears, long and with a distinctive fold. It is extremely similar to the much rarer grey long-eared bat which was only validated as a distinct

species In biology, a species is the basic unit of Taxonomy (biology), classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of ...

in the 1960s. An adult brown long-eared bat has a body length of 4.5–4.8 cm, a tail of 4.1–4.6 cm, and a forearm length of 4–4.2 cm. The ears are 3.3–3.9 cm in length, and readily distinguish the long-eared bats from most other bat species. They are relatively slow flyers compared to other bat species.

Habitat

The brown long-eared bat is found throughout Europe, with the exception of Greece, southern Italy and southern Spain. It is found to the east up to the Urals and Caucasus. The UK distribution can be found on the

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website and can be see
here
Brown long-eared bats regularly utilise buildings roosting in undisturbed roof spaces either singly, in crevices and timber, or in clusters around chimneys and ridge ends. This species also roosts in treeholes, bat boxes and

cave A cave or cavern is a natural void in the ground, specifically a space large enough for a human to enter. Caves often form by the weathering of rock and often extend deep underground. The word ''cave'' can refer to smaller openings such as se ...

s which are important as winter hibernation sites. The roosts in trees may be close to the ground. Emergence from roost sites usually only occurs in the dark, around an hour after sunset. It hunts above woodland, often by day, and mostly for moths, but its diet also consists of

earwigs Earwigs make up the insect order Dermaptera. With about 2,000 species in 12 families, they are one of the smaller insect orders. Earwigs have characteristic cerci, a pair of forcep-like pincers on their abdomen, and membranous wings folded ...

, flies, and beetles, gleaning these insects from leaves and bark. Prey is probably detected by sight and sound using the large eyes and ears, not by echolocation. A study by Eklöf and Jones (2003) demonstrated the ability of the brown long-eared bat to visually detect prey. Under experimental conditions, brown long-eared bats showed a preference for situations where sonar and visual cues were available. However, visual cues were more important than sonar cues and the bats were unable to detect prey items using only sonar cues. Brown long-eared bats have relatively large eyes and ears and it is likely that visual information and passive listening allow this species to detect prey in cluttered environments.

Echolocation

Echolocation is not used to find prey. The frequencies used by this bat species for echolocation lie between 27–56 kHz, have most energy at 35 kHz and have an average duration of 2.5 ms. However, unlike most bats, the long-eared can hunt their prey by hearing alone. Their hearing is sensitive enough to hear a moth in flight. This hunting strategy evolved because prey items, namely certain moth species evolved the ability to hear the echolocation and take evading action.

Gallery

File:Haeckel Chiroptera Plecotus auritus 1.jpg, Drawing by Ernst Haeckel File:Haeckel Chiroptera Plecotus auritus 2.jpg, Detail of head File:Plecotus auritus ras.jpg, Woodcut from R. A. Sterndale, 1884 File:Braunes Langohr (Plectus auritus).jpg, Exemplar in the Oxford University Museum of Natural History File:Plecotus auritus 2016 stamp of Romania.jpg, Romanian stamp File:Plecotus auritus hibernate with one ear out.jpg

References

;Sources
Woodland Management For Bats Guide
* * (2005): The role of eyespots as anti-predator mechanisms, principally demonstrated in the Lepidoptera. '' Biol. Rev.'' 80(4): 573–588. (HTML abstract)

External links

ARKive
Photographs {{Authority control Plecotus Bats of Europe Mammals described in 1758 Taxa named by Carl Linnaeus