The serotine bat (''Eptesicus serotinus''), also known as the common serotine bat, big brown bat, or silky bat,
is a fairly large
Eurasia
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 archipelago ...
n
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 ...
with quite large
ear
An ear is the organ that enables hearing and, in mammals, body balance using the vestibular system. In mammals, the ear is usually described as having three parts—the outer ear, the middle ear and the inner ear. The outer ear consists of ...
s. It has a wingspan of around and often hunts in
woodland
A woodland () is, in the broad sense, land covered with trees, or in a narrow sense, synonymous with wood (or in the U.S., the ''plurale tantum'' woods), a low-density forest forming open habitats with plenty of sunlight and limited shade (se ...
. It sometimes roosts in buildings, hanging upside down, in small groups or individually. The name serotine is derived from the Latin ''serotinus'', which means 'evening', while the generic name derives from Greek ἔπιεν and οίκος, which means 'house flyer'.
Taxonomy
The following subspecies have been recognised.
*''Eptesicus serotinus boscai'': southern
Iberia
The Iberian Peninsula (),
**
* Aragonese and Occitan: ''Peninsula Iberica''
**
**
* french: Péninsule Ibérique
* mwl, Península Eibérica
* eu, Iberiar penintsula also known as Iberia, is a peninsula in southwestern Europe, defi ...
and
Morocco
Morocco (),, ) officially the Kingdom of Morocco, is the westernmost country in the Maghreb region of North Africa. It overlooks the Mediterranean Sea to the north and the Atlantic Ocean to the west, and has land borders with Algeria to ...
*''Eptesicus serotinus pashtonus'':
Pakistan
Pakistan ( ur, ), officially the Islamic Republic of Pakistan ( ur, , label=none), is a country in South Asia. It is the world's List of countries and dependencies by population, fifth-most populous country, with a population of almost 24 ...
and
Afghanistan
Afghanistan, officially the Islamic Emirate of Afghanistan,; prs, امارت اسلامی افغانستان is a landlocked country located at the crossroads of Central Asia and South Asia. Referred to as the Heart of Asia, it is bordere ...
*''Eptesicus serotinus serotinus'': northern and eastern Europe and western Asia
*''Eptesicus serotinus turcomanus'': central Asia and
Xinjiang
Xinjiang, SASM/GNC: ''Xinjang''; zh, c=, p=Xīnjiāng; formerly romanized as Sinkiang (, ), officially the Xinjiang Uygur Autonomous Region (XUAR), is an autonomous region of the People's Republic of China (PRC), located in the northwest ...
The
Oriental serotine
The Oriental serotine (''Eptesicus pachyomus'') is a species of bat in the family Vespertilionidae. It is widespread and found throughout Asia.
Taxonomy
This species was formerly considered a subspecies of the serotine bat (''E. serotinus''), ...
(''E. pachyomus'') and its constituent subspecies were formerly considered a subspecies of ''E. serotinus'', comprising its eastern populations, and is still considered its closest relative, but phylogenetic evidence indicates a deep genetic divergence between ''E. serotinus'' and ''E. pachyomus'', so they have been split as distinct species. The same occurred with the
meridional serotine (''E. isabellinus''), which was formerly thought to comprise the southernmost populations of ''E. serotinus''.
Description
The serotine bat has long fur which on the back is smoky-brown in colour, while the underparts are a paler yellowish-brown, the nose and triangular shaped ears are black, and the membranes of the wings are dark black or brown. The juveniles are darker than the adults. Serotine bats are easy to identify in flight, because its broad wings combined with its slow, highly manoeuvrable, flapping flight interspersed with brief glides is distinctive.
The
tragus has a relatively thin and pointed shape and is not kidney shaped as in ''
Nyctalus
''Nyctalus'' is a genus of vespertilionid bats commonly known as the noctule bats. They are distributed in the temperate and subtropical areas of Europe, Asia and North Africa.
There are eight species within this genus:
* Birdlike noctule, ''Ny ...
''.
Distribution
The serotine bat has a
Palaearctic
The Palearctic or Palaearctic is the largest of the eight biogeographic realms of the Earth. It stretches across all of Eurasia north of the foothills of the Himalayas, and North Africa.
The realm consists of several bioregions: the Euro-Sibe ...
distribution lying between about 58 degrees and 30 degrees from southern
Great Britain
Great Britain is an island in the North Atlantic Ocean off the northwest coast of continental Europe. With an area of , it is the largest of the British Isles, the largest European island and the ninth-largest island in the world. It is ...
and
Spain
, image_flag = Bandera de España.svg
, image_coat = Escudo de España (mazonado).svg
, national_motto = ''Plus ultra'' (Latin)(English: "Further Beyond")
, national_anthem = (English: "Royal March")
, i ...
in the west, east to along the
Himalayas
The Himalayas, or Himalaya (; ; ), is a mountain range in Asia, separating the plains of the Indian subcontinent from the Tibetan Plateau. The range has some of the planet's highest peaks, including the very highest, Mount Everest. Over 100 ...
to northeastern
India
India, officially the Republic of India (Hindi: ), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the so ...
and along the
Tian Shan
The Tian Shan,, , otk, 𐰴𐰣 𐱅𐰭𐰼𐰃, , tr, Tanrı Dağı, mn, Тэнгэр уул, , ug, تەڭرىتاغ, , , kk, Тәңіртауы / Алатау, , , ky, Теңир-Тоо / Ала-Тоо, , , uz, Tyan-Shan / Tangritog‘ ...
to southern
Mongolia
Mongolia; Mongolian script: , , ; lit. "Mongol Nation" or "State of Mongolia" () is a landlocked country in East Asia, bordered by Russia to the north and China to the south. It covers an area of , with a population of just 3.3 million, ...
and northern
China
China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's most populous country, with a population exceeding 1.4 billion, slightly ahead of India. China spans the equivalent of five time zones and ...
, and south to
Turkey
Turkey ( tr, Türkiye ), officially the Republic of Türkiye ( tr, Türkiye Cumhuriyeti, links=no ), is a list of transcontinental countries, transcontinental country located mainly on the Anatolia, Anatolian Peninsula in Western Asia, with ...
and
Iran
Iran, officially the Islamic Republic of Iran, and also called Persia, is a country located in Western Asia. It is bordered by Iraq and Turkey to the west, by Azerbaijan and Armenia to the northwest, by the Caspian Sea and Turkmeni ...
. It has been recorded as a vagrant on
Lanzarote in the
Canary Islands
The Canary Islands (; es, Canarias, ), also known informally as the Canaries, are a Spanish autonomous community and archipelago in the Atlantic Ocean, in Macaronesia. At their closest point to the African mainland, they are west of Morocc ...
.
[
]
Habitat
The serotine bat utilises in a wide variety of habitats including temperate and subtropical dry forest, maquis
Maquis may refer to:
Resistance groups
* Maquis (World War II), predominantly rural guerrilla bands of the French Resistance
* Spanish Maquis, guerrillas who fought against Francoist Spain in the aftermath of the Spanish Civil War
* The network ...
, agricultural land, semi-desert and suburban areas.[
]
Biology
In Europe serotine bats start to establish maternity colonies consisting almost exclusively of females from late May. Colonies usually remain at a single roost site during the breeding season, although occasionally the larger colonies will change roost sites. The female bats usually give birth to a single pup in early July, though births have been recorded as late as mid-August.
The female bats normally give birth to a single young in late summer, and the baby is occasionally carried by its mother for the first few days. The young bats usually make their first flights at around three weeks old, and at six weeks they can forage for themselves. Breeding colonies usually disperse by early September, although a few bats may use the colony site as a roost until early October. The male bats probably remain solitary or in small groups but are occasionally found with females in spring or autumn. Mating seems to take place in the autumn, but very little is known about the mating behaviour. Both sexes reach sexual maturity at one year old.[
Serotine bats mainly use buildings for summer roosts, especially those older buildings with high gables and cavity walls, and often occur in churches; modern buildings are used infrequently. The roost is normally accessed at or near the gable apex or the lower eaves. The serotine bat is hardly ever found in trees, which were the most likely pre-human roost sites, and the species seems to be very oriented towards using buildings. The roost is sometimes shared with ]pipistrelle
''Pipistrellus'' is a genus of bats in the family Vespertilionidae and subfamily Vespertilioninae. The name of the genus is derived from the Italian word , meaning "bat" (from Latin "bird of evening, bat").
The size of the genus has been cons ...
s or brown long-eared bat
The brown long-eared bat or common long-eared bat (''Plecotus auritus'') is a small Eurasian insectivorous bat. It has distinctive ears, long and with a distinctive fold. It is extremely similar to the much rarer grey long-eared bat which was o ...
s, and this species has also been recorded associating with Natterer's bat
Natterer's bat (''Myotis nattereri'') is a European vespertilionid bat with pale wings. It has brown fur tending to greyish-white on its underside. It is found across most of the continent of Europe, parts of the Near East and North Africa. It fe ...
s, whiskered bat
The whiskered bat (''Myotis mystacinus'') is a small European bat with long fur. Although uncommon, ''M. mystacinus'' is often found around human habitation and around water; it is similar to Brandt's bat
Brandt's bat or Brandt's myotis (''M ...
s and noctule bats. Only a few serotine bats have been found in winter, but it seems likely that most hibernate in buildings in cavity walls and disused chimneys. There are a few records of them being found in the coldest parts of caves, either in roof crevices or in accumulations of boulders.[
The foraging activity of serotine bats peaks at dusk, and there is a second period of activity around dawn. They commute on average to and from feeding areas per night, and forage in up to five distinct areas per night. This species uses three main feeding strategies: short flights, ground feeding and aerial hawking. It normally forages quite low, above the ground.]
Diet
Similarly to the ''Nyctalus
''Nyctalus'' is a genus of vespertilionid bats commonly known as the noctule bats. They are distributed in the temperate and subtropical areas of Europe, Asia and North Africa.
There are eight species within this genus:
* Birdlike noctule, ''Ny ...
'' or ''Plecotus
''Plecotus'' is a genus of vesper bat, commonly called long-eared bats. They are found throughout Eurasia and northern Africa. Many species in the genus have only been described and recognized in recent years.
Species
Genus ''Plecotus'' – lon ...
'' species, the serotine is mainly an aerial hawker focusing on hunting flying insects.
Echolocation
The frequencies used by this bat species for echolocation lie between 25–55 kHz
The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), equivalent to one event (or cycle) per second. The hertz is an SI derived unit whose expression in terms of SI base units is s−1, meaning that on ...
, have most energy at 31 kHz and have an average duration of 8.8 ms.
Conservation
The serotine bat has declined in many areas in its European range. Loss of feeding habitat is thought to have played a part in the decline. In addition, as this bat almost exclusively roosts in buildings, it is highly vulnerable to disturbance from construction work and toxic timber treatments. In the United Kingdom
The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the continental mainland. It comprises England, Scotland, Wales and North ...
serotine bats benefit from a very comprehensive level of legal protection, as is the case across much of Europe.[
]
References
External links
*
*
{{Taxonbar, from=Q214869
Bats of Africa
Bats of Asia
Bats of Europe
Mammals of Azerbaijan
Eptesicus
Mammals described in 1774
Taxa named by Johann Christian Daniel von Schreber