Greater Horseshoe Bat
Encyclopedia
The Greater Horseshoe Bat (Rhinolophus ferrumequinum) is a Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...

an bat
Bat
Bats are mammals of the order Chiroptera "hand" and pteron "wing") whose forelimbs form webbed wings, making them the only mammals naturally capable of true and sustained flight. By contrast, other mammals said to fly, such as flying squirrels, gliding possums, and colugos, glide rather than fly,...

 of the Rhinolophus genus. Its distribution covers Europe, Africa, South Asia and Australia. It is the largest of the European Horseshoe Bats and is thus easily distinguished from other species. The species is sedentary, travelling between 20 and 30 km between the winter and summer roosts, with the longest recorded movement being 180 km. The species is notable as having the oldest recorded age for any European bat, with a bat living for over 30 years. The frequencies used by this bat species for echolocation lie between 69–83 kHz, have most energy at 81 kHz and have an average duration of 37.4 ms.

Description

The greater horseshoe bat is the largest bat in Europe. It has a distinctive noseleaf, which has a pointed upper part and a horseshoe shaped lower part. Its horseshoe noseleaf helps to focus the ultrasound
Ultrasound
Ultrasound is cyclic sound pressure with a frequency greater than the upper limit of human hearing. Ultrasound is thus not separated from "normal" sound based on differences in physical properties, only the fact that humans cannot hear it. Although this limit varies from person to person, it is...

 it uses to 'see'. The greater horseshoe bat also has tooth and bone structures that are distinct from that of other rhinolophids. Its first premolar on the upper jaw protrudes from the row of teeth. For other horseshoe bats, this premolar is very small or non-existent. Also in comparison to its relatives, the greater horseshoe bat has relatively short third and fourth metacarpal bones in its wings. It also lacks a tragus. The Greater Horseshoe Bat is on average between 57 and 71 mm long, with a 35–43 mm tail and a 350–400 mm wingspan. The fur of the species is soft and fluffy, with the base of hairs being light grey, the dorsal side hair grey brown and the ventral side grey-white, with juvenile bats having more of an ash-grey tint to their fur. Wing membranes and ears are light grey-brown. It weighs up to 30 grams.

Distribution

The greater horseshoe bat ranges from North Africa and southern Europe through south-west Asia, the Caucasus, Iran, Afghanistan, Pakistan and the Himalayas to south-eastern China, Korea, and Japan. Generally the bats lives below 800 m asl, but it also lives, depending on roost availability and humidity, 3,000 m asl in the Caucasus.

Habitat and roosting

Pastures, deciduous temperate woodland, Mediterranean and sub-mediterranean shrubland and woodlands are common foraging foraging habitats for this species. In northern parts of its range, the horseshoe uses warm underground sites, both natural and artificial, as summer roosts as well as attics. Where the species occupies buildings, proximity to good foraging areas and underground sites for torpor at various times of year and for winter hibernation as well as the building's own features are important.

Horseshoe bats hibernate in cold underground sites like large caves, during the winter. The bat require a certain temperature and humidity limit, but thus can vary with age, sex and condition. Horseshoe bats are active throughout the year in the southern parts of their range. Horse bats commonly travel distances of 20-30 km between winter and summer roosts, with longest distance recorded being 180 km. Horseshoes bats also live in montane forests among the mountains and valleys of the Himalaya in South Asia and roosts in caves, old temples, old and ruined buildings in tight clusters.

Diet and hunting

The species feeds preferentially on lepidoptera
Lepidoptera
Lepidoptera is a large order of insects that includes moths and butterflies . It is one of the most widespread and widely recognizable insect orders in the world, encompassing moths and the three superfamilies of butterflies, skipper butterflies, and moth-butterflies...

 (moths), making up around 41% of the diet - in particular the noctuidae
Noctuidae
The Noctuidae or owlet moths are a family of robustly-built moths that includes more than 35,000 known species out of possibly 100,000 total, in more than 4,200 genera. They constitute the largest family in the Lepidoptera....

 species , Coleoptera (beetles) constitute around 33% of the diet, of which dung beetles
Dung beetle
Dung beetles are beetles that feed partly or exclusively on feces. All of these species belong to the superfamily Scarabaeoidea; most of them to the subfamilies Scarabaeinae and Aphodiinae of the family Scarabaeidae. This beetle can also be referred to as the scarab beetle. As most species of...

 are often taken Aphodius
Aphodius
Aphodius is a genus of beetles in the Scarabaeidae family.-Species:This genus has numerous species:* Aphodius ater * Aphodius bimaculatus * Aphodius borealis Gyllenhal, 1827...

 rufipes is one such dung beetle forming an especially important part of its diet. Cow pats are part of its life cycle, acting as food source and habitat for the larvae
Larvae
In Roman mythology, lemures were shades or spirits of the restless or malignant dead, and are probably cognate with an extended sense of larvae as disturbing or frightening...

. Up to 100 larvae can be found in a single cow pat. The beetle is most abundant in August when the young bats begin their first feeeding flights). The remainder of the diet being hymenoptera
Hymenoptera
Hymenoptera is one of the largest orders of insects, comprising the sawflies, wasps, bees and ants. There are over 130,000 recognized species, with many more remaining to be described. The name refers to the heavy wings of the insects, and is derived from the Ancient Greek ὑμήν : membrane and...

 and diptera
Diptera
Diptera , or true flies, is the order of insects possessing only a single pair of wings on the mesothorax; the metathorax bears a pair of drumstick like structures called the halteres, the remnants of the hind wings. It is a large order, containing an estimated 240,000 species, although under half...

. Cockchafer
Cockchafer
The cockchafer is a European beetle of the genus Melolontha, in the family Scarabaeidae....

s also form an important part of its diet.

The feeding area from the maternity roost is typically of radius 4 km, as neither the lactating females or young can travel far. In late August and September the bats feed on cranefly, to fatten up before hibernation. Breeding females depend on beetles from April until June, and moths from June to August.

The Greater Horseshoe Bat leaves its roost at dusk, and its flying is made up of slow, fluttering travel with short glides, normally between 0.3 and 6 metres above the ground, with little hunting during wet and windy weather. It hunts in terrain with poor tree cover such as hillsides, cliff faces and in gardens, locating insects from its resting place and then intercepting them. The species has the ability to pick food up off the ground while still in flight, and indeed drinks during low-level flight or while hovering. The feeding range of colonies in England is between 8 and 16 kilometres.

Mating and reproduction

Female bats become sexually mature at the age of three years while males are sexually mature at two years. A female usually will not have her first young until her fifth year. Most matings take place in the fall, however some occur in the spring. After a mating, the male will secret a vaginal plug in the female’s vulva. This may be used to keep the sperm of other males out, or to hold the sperm in for fertilzation. Females tend to control fertilizations which take place later. Females will raise their young in maternity roosts. Each season, a female produces one offspring. Most young are born in June or July. When they are seven days old, young can open their eyes and at their third or fourth week they can fly. Young can live the roost their seventh or eighth week.

Status and conservation

In general the greater horseshoe bat is list as Least Concern by the ICUN for because: "This species has a large range. Although there have been marked and well-documented declines in some areas, the species remains widespread, abundant, and apparently stable in other areas. Assessed as Least Concern". However, the overall greater horseshoe bat population is declining. They are largely uncommon in much of their range. Despite this, they appear to be abundant and widespread in at least parts of south-west Asia and the Caucasus least parts of south-west Asia and the Caucasus. Also in some northwest European countries, there appears to be some stabilisation and/or recovery. Less is known about bat trends in other parts of Europe. It is extinct in Malta. Fragmentation/isolation of habitats, change of management regime of deciduous forests and agricultural areas, loss of insects caused by pesticides, and disturbance and loss of underground habitats and attics are the major threats to the greater horseshoe bat. Deforestation, mostly caused by logging operations and the conversion of land for agricultural and other uses, threatens the species in South Asia.

Status in Britain

The species is rare in Britain, confined to just a small number of sites. Its distribution can be found on the National Biodivesity website here. Its breeding sites include Brockley Hall Stables
Brockley Hall Stables
Brockley Hall Stables is a 0.065 hectare biological Site of Special Scientific Interest near the village of Brockley, North Somerset, notified in 1987.-Biological Interest:...

 near Bristol
Bristol
Bristol is a city, unitary authority area and ceremonial county in South West England, with an estimated population of 433,100 for the unitary authority in 2009, and a surrounding Larger Urban Zone with an estimated 1,070,000 residents in 2007...

, Iford Manor near Bath, and Littledean Hall
Littledean Hall
Littledean Hall is a country house in the village of Littledean, Gloucestershire, England. It is reputedly one of the most haunted houses in England and is thought to be the oldest house in the United Kingdom which is still occupied...

 in the Forest of Dean
Forest of Dean
The Forest of Dean is a geographical, historical and cultural region in the western part of the county of Gloucestershire, England. The forest is a roughly triangular plateau bounded by the River Wye to the west and north, the River Severn to the south, and the City of Gloucester to the east.The...

. Its winter hibernation sites include Banwell Caves
Banwell Caves
Banwell Caves are a 1.7-hectare geological and biological Site of Special Scientific Interest near the village of Banwell, North Somerset, England notified in 1963....

 and Compton Martin Ochre Mine
Compton Martin Ochre Mine
Compton Martin Ochre Mine is a 0.85 hectare geological and biological Site of Special Scientific Interest located on the north side of the Mendip Hills, immediately south west of Compton Martin village, Somerset, notified in 1988.-Geological Interest:...

 in the Mendip Hills
Mendip Hills
The Mendip Hills is a range of limestone hills to the south of Bristol and Bath in Somerset, England. Running east to west between Weston-super-Mare and Frome, the hills overlook the Somerset Levels to the south and the Avon Valley to the north...

, Chilmark Quarries
Chilmark Quarries
Chilmark Quarries is a 9.65 hectare biological and geological Site of Special Scientific Interest, in the ravine south of the village of Chilmark in Wiltshire, notified in 1977....

 in Wiltshire
Wiltshire
Wiltshire is a ceremonial county in South West England. It is landlocked and borders the counties of Dorset, Somerset, Hampshire, Gloucestershire, Oxfordshire and Berkshire. It contains the unitary authority of Swindon and covers...

, and Combe Down and Bathampton Down Mines
Combe Down and Bathampton Down Mines
Combe Down and Bathampton Down Mines is a 6.22 hectare Site of Special Scientific Interest in Bath and North East Somerset, notified in 1991 because of the Greater and Lesser Horseshoe bat population....

 near Bath. In Dorset, the species roosts at Bryanston
Bryanston SSSI, Dorset
Bryanston SSSI is a 0.3 hectare biological Site of Special Scientific Interest in Dorset, England notified in 1977.It is used as a roost site by Greater Horseshoe bats.-Source:* -External links:*...

, Creech Grange
Creech Grange
Creech Grange is an elegant country house, south of Wareham at the foot of the Purbeck Hills.- History :The house was built by Sir Oliver Lawrence, who acquired the land from the former Bindon Abbey, near Wool, after Henry VIII had abolished the monasteries in 1539...

 and in Belle Vue Quarry
Belle Vue Quarry
Belle Vue Quarry is a 3.2 hectare biological Site of Special Scientific Interest in Dorset, notified in 1977.It is used as a roosting site by Greater Horseshoe bats.-Source:* -External links:*...

. The species also occurs at Berry Head
Berry Head
Berry Head is a coastal headland at the southern end of Torbay, to the southeast of Brixham, Devon, England.-National Nature Reserve:Berry Head to Sharkham Point is a haven for several nationally rare and threatened species which are dependent upon the thin limestone soils, mild climate and exposed...

 in Devon
Devon
Devon is a large county in southwestern England. The county is sometimes referred to as Devonshire, although the term is rarely used inside the county itself as the county has never been officially "shired", it often indicates a traditional or historical context.The county shares borders with...

 and has a monitored roost site at Woodchester Mansion in Stroud.

The species has disappeared from over half of its former range within the United Kingdom, with about 1% of the population surviving. Like all horseshoe bats it is sensitive to disturbance, and is threatened by the use of insecticides and the elimination of beetles by the changing agricultural practices.

There are seventeen recorded species of bat in Britain as of recent survey results.The greater horseshoe bat is one of the rarest. There are currently 35 recognised maternity and all-year roosts and 369 hibernation sites. Current estimates range between 4000 and 6600 individuals. Greater Horseshoes have declined for numerous reasons ranging from the use of agrichemical
Agrichemical
Agrochemical , a contraction of agricultural chemical, is a generic term for the various chemical products used in agriculture. In most cases, agrichemical refers to the broad range of pesticides, including insecticides, herbicides, and fungicides...

s (Ivermectin in particular) to loss of habitat and redundancy of farming methods.
Avermectin kills off insect larvae and thus a decrease in the abundance of food for the Horseshoes, causing them to travel further and face increased dangers.

Habitat loss is primarily the lack of established hedgerows and deciduous woodland-pasture ecotones.
Modern farming methods have seen the reduction of cattle-grazing and this has impacted the Horseshoes who previously found that dung attracted insects and sustained entomogenous populations, giving their prey a stable population.

External links

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