Emballonura monticola

Geographic Range

Lesser sheath-tailed bats can be found in the Malay Peninsula and the surrounding areas, including some offshore islands.

• Biogeographic Regions
• oriental oriental
  • native native

Habitat

Lesser sheath-tailed bats are often found in areas of lowland forest and subtropical/tropical moist areas, primarily up to 1800 m. This species roosts in caves and cave entrances, rock crevices, large tree holes, and forests. They can be found in smaller numbers hanging under tables and buttresses in lowland forest Malaysia, hanging rock in tropical lowland forests and manmade caves in Thailand.

• Habitat Regions
• tropical tropical
• terrestrial terrestrial

• Terrestrial Biomes
• forest forest
• rainforest rainforest

• Other Habitat Features
• caves

Physical Description

Lesser sheath-tailed bats have very smooth and shiny fur that ranges from dark to reddish brown. Their underside is brown and wings are black. They have triangular shaped ears, large eyes and a pointed, simple nose that has no noseleaf. A short tail protrudes from the membrane between the legs, and, when the legs are stretched, the tail is retracted in a membrane (uropatagium) and unseen. When the wings of lesser sheath-tailed bats are relaxed, they have an extra fold that distinguishes them from other bat families. This species can fly straight and fast due to the shape of their bodies, allowing them to follow gaps formed by streams or paths in the forest. The forearm is generally 43 to 45 mm in length. The dental formula is (i 2/3, c 1/1, pm 2/2, m 3/3) x 2 = 34. g. Emballonura are the only genera in the family to have two pairs of upper incisors. A "W" pattern of cusps and ridges is also found in their molars.

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

Reproduction

Lesser sheath-tailed bats are believed to be polygynous, though little information is available regarding the mating systems of this species.

• Mating System
• polygynous polygynous

Lesser sheath-tailed bats have two breeding seasons per year, the first in February through March and the second in October through November. During each birth period, females give birth to a single offspring. The pup weighs about a quarter of the mother's weight.

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

Female lesser sheath-tailed bats scoop their pups to their body with their wings as soon as a pup is born, preventing it from falling. The pup clings to its mother's body while she forages until the pup becomes too heavy to carry. Soon after weaning, usually within a year, the pup becomes a mature adult.

• Parental Investment
• female parental care female parental care
• pre-hatching/birth
  • provisioning
    • female
  • protecting
    • female
• pre-weaning/fledging
  • provisioning
    • female
  • protecting
    • female
• pre-independence
  • provisioning
    • female
  • protecting
    • female

Lifespan/Longevity

Little information is available regarding the lifespan of lesser sheath-tailed bats.

Behavior

Daytime roosts of lesser sheath-tailed bats usually range from 2 to 20 individuals, though some larger colonies have been found in caves ranging from 100 to 150 bats.

• Key Behaviors
• arboreal arboreal
• flies
• nocturnal nocturnal
• motile motile
• social social
• colonial colonial

Home Range

Little information is available regarding the home range of lesser sheath-tailed bats.

Communication and Perception

Lesser sheath-tailed bats have a very distinct echolocation call lasting 6 to 8 milliseconds. Each call consists of a short sweep up in the frequency range, then a steady constant frequency staying between 48 and 51 kHz. The call finishes with a sweep down through its frequency range. Emballonura monticola studied in Singapore were recorded as having a maximum frequency of 49.3 kHz and a minimum frequency of 46.0 kHz.

• Communication Channels
• acoustic acoustic

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

Food Habits

Lesser sheath-tailed bats primarily hunt insects in dense forests. They have also been observed during the day in dense shade foraging for insects. This species has also occasionally been observed eating fruit.

• Primary Diet
• carnivore carnivore
  • insectivore insectivore

• Animal Foods
• insects

• Plant Foods
• fruit

Predation

Little information is available regarding predators of lesser sheath-tailed bats.

Ecosystem Roles

As insectivores, lesser sheath-tailed bats may regulate insect populations. Because lesser sheath-tailed bats occasionally eat fruit, they may contribute to seed dispersal.

• Ecosystem Impact
• disperses seeds

Economic Importance for Humans: Positive

Many bats, including lesser sheath-tailed bats, contribute to the control of insect pests on crops.

• Positive Impacts
• controls pest population

Economic Importance for Humans: Negative

No information known.

Conservation Status

Lesser sheath-tailed bats are declining in population but are still considered of Least Concern on the IUCN Red List because of their location. Most members of this species are currently located within protected areas, and populations are decreasing at a rate that ranks them as non-threatened. Increased deforestation from illegal logging and forest fires as well as destruction of caves due to limestone extraction are of increasing concern. Both scientific groups and retailers are promoting educational programs to raise awareness

Other Comments

Because of continued demand for palm oil, which is used in margarine, lipstick, and detergent, deforestation is continuing in prime habitat of lesser sheath-tailed bats. Malaysia and Indonesia together contribute about 88% of the world's palm oil. Large retailers, including Migros, Switzerland's largest retail chain, have expressed their concern for the destruction of these habitats due to palm oil production. Migros has recently ensured all of their products made of palm oil will not contribute to deforestation.

Additional Links

Encyclopedia of Life

Contributors

Kelly Kraemer (author), Northern Michigan University, John Bruggink (editor), Northern Michigan University, Gail McCormick (editor), Animal Diversity Web Staff.

References

Baker, N. 2009. "Lesser Sheath-tailed Bat" (On-line). EcologyAsia.com. Accessed February 12, 2009 at www.ecologyasia.com/verts/bats/Lesser_sheath-tailed_bat.htm .

Bates, P., C. Francis, T. Kingston. 2008. "IUCNresource.org" (On-line). The IUCN Red List of Threatened Species. Accessed February 08, 2009 at www.iucnredlist.org/details/7674 .

Nowak, R. 1999. Emballonura monticola. Pp. 310-311 in Walker's Mammals of the World , Vol. 1, Sixth Edition. Baltimore and London: John Hopkins University Press.

Pottie, S., D. Lane, T. Kingston, B. Lee. 2005. The microchiropteran bat fauna of Singapore. Acta Chiropterologica , 7(2): 237-247. Accessed March 10, 2009 at http://www.mbcru.com/index_files/Pottie%20et%20al.%202005--Acta.pdf .

Voigt, C. 2004. Sac-Winged Bats, Sheath-Tailed Bats, and Ghost Bats (Emballonuridae). Pp. 355-265 in Grzimek's Animal Life Encyclopedia , Vol. Vol. 13, 2nd Edition. Detroit: Gale Virtual Reference Library. Accessed March 10, 2009 at http://find.galegroup.com/gvrl/infomark.do?&contentSet=EBKS&type=retrieve&tabID=T001&prodId=GVRL&docId=CX3406700828&source=gale&userGroupName=lom_nmichu&version=1.0 .

Gale Group. 2003. Emballonura monticola. Pp. 362-363 in Grzimek's Animal Life Encyclopedia , Vol. 13, Second Edition. Farmington Hills, MI: Thomson Gale.

2009. "Lesser sheath-tailed bat" (On-line). ARKIVE.org. Accessed February 12, 2009 at www.arkive.org/Lesser-sheath-tailed-bat/emballonula-monticola/description.html .

EuropaWorld. 2001. "Swiss Palm Oil Products May Help Save Indonesian Forests" (On-line). Europaworld.org. Accessed March 12, 2009 at http://www.europaworld.org/issue66/swisspalm25102.htm .