Rhinolophus euryale

Geographic Range

Mediterranean horseshoe bats occur mostly in Europe, including the Balkans and Mediterranean region. They are also found on the islands of Sicily, Sardinia, and Corsica. The northern most range includes Slovakia, northern Italy and southern France. They have also been reported in northern Africa.

• Biogeographic Regions
• palearctic palearctic
  • native native

Habitat

Mediterranean horseshoe bats inhabit warm, forested regions in foothills and mountains. They favor karst formations with numerous caves located near water sources. They also favor broadleaved woodlands and olive groves. They spend summers roosting in caves and underground shelters. In more northern regions, warm attics are used.

• Habitat Regions
• temperate temperate

• Terrestrial Biomes
• forest forest
• mountains mountains

Physical Description

Mediterranean horseshoe bats are medium-sized, weighing betwen 8 and 17.5 g. Total length of these animals is 65 to 88 mm, and wingspan is between 300 and 320 mm. Females are often larger than males.

The horseshoe and lips of the bat are light brown, and the ears and wing membranes are light gray. The fur of this bat is sparse, becoming light gray toward the base. The back is a gray-brown, with a light reddish or pinkish tint. The underside is gray-white to a yellowish-white. The boundary between dorsal and ventral color is indistinct. Darker hairs may be present around the eyes.

The wings of the bat are broad (suggesting life in the forest), with the second phalanx of the fourth finger having more than twice the length of the first. When at rest, the third to fifth fingers are bent 180º at the joint between the first and second phalanges. Because of this, these bats cannot be completely wrapped by their wing membranes.

The species is nasal emitting, with an upper saddle process pointed and slightly curved downward. The lower saddle process is rounded when viewed from below, and is noticably shorter than the upper saddle process.

• Other Physical Features
• endothermic endothermic
• bilateral symmetry bilateral symmetry

• Sexual Dimorphism
• female larger

Reproduction

Not much detailed information is available regarding mating system of this species. Maternity roosts often contain 50 to 400 females with males often present.

Information on reproduction is sparse. Breeding is thought to occur once per year. Females give birth to one offspring which weighs approximately 4 grams at birth, and is ready to fly in early to mid August. In Bulgaria, young are ready to fly in mid July.

Within the genus Rhinolophus , some species are known to undergo delayed fertilization. Mating may occur in winter, and gestation, which is usually about 7 weeks, occurs in early spring. Most births in this genus occur in late spring or early Summer. Given that the young are flying in July or August, it is likely that Rhinolophus eurylate is similar.

In species of Rhinolophus for which data are available, lactation lasts for approximately one month. Sexual maturity is usually reached by two years of age.

• Key Reproductive Features
• iteroparous iteroparous
• seasonal breeding seasonal breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual sexual
• fertilization fertilization
• viviparous viviparous

No information about parental care is available, but in general females care for young in bats. Young bats are typically atricial, and in this genus, lactation is thought to last for about one month. The role of males in parental care has not been reported.

• Parental Investment
• no parental involvement
• altricial altricial
• pre-fertilization
  • protecting
    • female
• pre-hatching/birth
  • provisioning
    • female
  • protecting
    • female
• pre-weaning/fledging
  • provisioning
    • female
  • protecting
    • female
• pre-independence
  • protecting
    • female

Lifespan/Longevity

The lifespan of Mediterranean horseshoe bats is unknown. It is difficult to speculate on what the lifespan may be, as there is great variability within the genus. Some species on the Malay penninsula are reported to live for only about 6 or 7 years. However, one individual of the species Rhinolophus ferrumequinum in France was reported to have lived in excess of 27 years.

Behavior

Mediterranean horseshoe bats often roost together with other bat species including other horseshoe bats. Winter roosts are located in caves and tunnels with an approximate temperature of 10ºC. These bats hang freely from the ceiling, but, unlike many bats, their wings do not completely cover the body due to the anatomy of the wing. They are often in contact with other individuals. These bats are usually permanent residents, however they may migrate up to 134 km.

It has been noted that some members of the family may go into a state of torpor as an adaption to low temperatures. Some members of the genus Rhinolophus hibernate. However, it is not known for certain whether R. euryale undergoes such torpor or hibernation.

Most bats in the genus Rhinolophus are solitary foragers. The bats are typically nocturnal, and use echolocation to find prey items.

• Key Behaviors
• flies
• nocturnal nocturnal
• motile motile
• migratory migratory
• sedentary sedentary
• colonial colonial

Home Range

Th size of the home range of these animals has not been reported.

Communication and Perception

All members of the family Rhinolophidae emit FM-CF-FM echolocation calls. The bat produces high frequency, highly directional calls in the range of 101 to 108 kHz, this high frequency cannot be heard by tympanate moths, one of their favorite foods. The calls last approximately 20 to 30 ms. However, it should be stressed that this echolocation is used for foraging, not for communicating with conspecifics.

Because these bats are nocturnal and roost in dark caves, it is unlikely that they use a lot of visual signals in their communications with conspecifics. Other members of the genus are reported to use some vocal communication, Because these bats come into frequent contact with one another in roosts, it is likely that there is some tactile communication. Communcation through scent has not been documented, but may occur, as these are mammals.

• Communication Channels
• tactile tactile
• acoustic acoustic

• Perception Channels
• visual visual
• tactile tactile
• acoustic acoustic
• ultrasound ultrasound
• echolocation echolocation
• chemical chemical

Food Habits

Mediterranean horseshoe bats emerge in late twilight to feed on moths and other insects. They hunt at low altitudes on warm slopes and in relatively dense stands of trees or shrubs. The flight of the bat is slow and agile, and they have the ability to hover.

All members of the family Rhinolophidae use echolocation to find prey items. They are known to emit FM-CF-FM echolocation calls. These bats produce high frequency, highly directional calls in the range of 101 to 108 kHz, a frequency beyond the ability of tympanate moths to detect. The calls last approximately 20 to 30 ms.

• Primary Diet
• carnivore carnivore
  • insectivore insectivore

• Animal Foods
• insects

Predation

No information on predation is available

Ecosystem Roles

Mediterranean horseshoe bats consume large quantities of moths and other insects. They therefore affect insect communities negatively, but probably have an indirect positive effect on plant communities, by eliminating some herbivorous insects.

Economic Importance for Humans: Positive

Mediterranean horseshoe bats provide insect control within the ecosystem.

Economic Importance for Humans: Negative

There are no known adverse affects of Mediterranean horseshoe bats on humans.

Conservation Status

Rhinolophus euryale is the rarest of all European rhinolophids, and is classified as "Vulnerable" in the IUCN Red List. Data are scarce on population estimates, however, it is known there was a 70% decline in numbers in France between 1940 and 1980. There was also a serious population decrease in Slovakia. Because of the use of pesticides by humans, many species of insectivorous bats have suffered, and the timing of decline in this species corresponds to the increased use of pesticides after World War II.

Rhinolophus euryale seems particularly sensitive to human disturbance, and because it mainly roosts in underground shelters, including caves, protection of such sites is a key conservation strategy.

Other Comments

Incidents of albinism have been recorded.

Additional Links

Encyclopedia of Life

Contributors

Nancy Shefferly (editor), Animal Diversity Web.

Paul Scharine (author), University of Wisconsin-Stevens Point, Chris Yahnke (editor, instructor), University of Wisconsin-Stevens Point.

References

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

Nowak, R. 1999. Walker's Mammals of the World, Sixth Edition . Baltimore and London: The Johns Hopkins University Press.

Russo, D., G. Jones, A. Migliozzi. 2002. Habitat selection by the Mediterranean horseshoe bat, in a rural area of southern Italy and implications for conservation. Biological Conservation , 107 (1): 71-81.

Russo, D., G. Jones, M. Mucedda. 2001. Influence of age, sex and body size on echolocation calls of Mediterranean and Mehely's horseshoe bats. Mammalia , 65 (4): 429-436.

Schober, W., E. Grimmberger. 1997. The Bats of Europe and North America . Neptune City, NJ: TFH Publications.