Cynopterus sphinxgreater short-nosed fruit bat

Geographic Range

The short-nosed fruit bat is found in Sri Lanka, India, South China, S.E. Asia, Western Malaysia, and Sumatra and neighboring small islands.

Habitat

Cynopterus sphinx is common in tropical forests and areas where fruit crops are cultivated. They can also be found in grassland and mangrove forests. They typically nest high in palm trees. The bats chew the fronds of the palms to constuct fairly simple tents. These bats are also known to construct tents by closely interweaving the leaves and twigs of creeping vines which cover buildings, but such nests are constructed only when palms are not available.

Physical Description

These bats have a relatively long snout. Their upper parts are typically bright orange with paler underparts, but there is much variation. The fur is very fine and silky. The wing span of the adult is about 48 cm.

  • Average mass
    75 g
    2.64 oz
    AnAge

Reproduction

In Central India, C. sphinx breeds twice per year. Females produce a single young at a time. The function of the female reproductive system is interesting in that each half of the bicornate uterus functions during alternate breeding cycles. The first pregancy cycle occurs from October through February/March. Mating occurs immediately postpartum, and a second offspring is born in July. Gestation 3-5 months. In 72% of bats, the first pregnancy occurs in the right horn of the uterus. The corpus luteum in the right ovary persists for some time after the pregancny and prevents ovulation from occuring in the right ovary during the second breeding cycle. This creats the pattern of alternate functioning of the two horns of the uterus. However, the corpus luteum in the left ovary does not persist until the beginning of the next breeding cycle. As yet, no reason has been found for the dominance of the right horn during the first breeding cycle.

Newborn bats weigh about 13.5 g and have a wingspan of 24 cm. By the time of weaning at 4 weeks of age, young bats weigh 25 g and have wings spanning 36 cm. Female short-nosed fruit bats reach sexual maturity at 5-6 months of age, but males are not capable of breeding until they are a year old.

  • Key Reproductive Features
  • gonochoric/gonochoristic/dioecious (sexes separate)
  • sexual
  • Average number of offspring
    1.2
    AnAge
  • Average gestation period
    120 days
    AnAge
  • Average age at sexual or reproductive maturity (female)
    Sex: female
    150 days
    AnAge
  • Average age at sexual or reproductive maturity (male)
    Sex: male
    525 days
    AnAge

Lifespan/Longevity

  • Average lifespan
    Status: captivity
    10 years
    AnAge

Behavior

The species is gregarious, and typically roots in same sex groups of 8-9 individuals. The sexes remain separate until the mating season, when group size increases. It is usual for 6-10 males and 10-15 females to share palm frond tents during the breeding season. Males stay with females for some time after mating, but later return to same sex groups. The adult sex ratio is very female biased. Researchers attribute this to the relatively rapid maturation of females compared to males.

Communication and Perception

Food Habits

These bats are frugivorous, they and locate their preferred food items by scent. They have been described as voracious feeders, eating more than their body weight in food in one sitting. Some preferred fruits include ripe guava, banana, chikus (a popular Indian fruit crop), dates and liches.

Economic Importance for Humans: Positive

These bats are important dispersers of date palm seeds, and pollinate many night blooming flowers.

Economic Importance for Humans: Negative

Short-nosed fruit bats inflict serious damage on many fruit crops, and are viewed by local people as a pest species. In addition, these bats are possible vectors for Japanese encephalitis, a very serious disease in humans.

Conservation Status

Contributors

Nancy Shefferly (author), Animal Diversity Web.

Glossary

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

chemical

uses smells or other chemicals to communicate

endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

forest

forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

oriental

found in the oriental region of the world. In other words, India and southeast Asia.

World Map

rainforest

rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Epiphytes and climbing plants are also abundant. Precipitation is typically not limiting, but may be somewhat seasonal.

scrub forest

scrub forests develop in areas that experience dry seasons.

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

tactile

uses touch to communicate

tropical savanna and grassland

A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.

savanna

A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.

temperate grassland

A terrestrial biome found in temperate latitudes (>23.5? N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.

References

Advani, R. 1982. Feeding, foraging and roosting behavior of the fruit eating bats and damage to fruit crops in Rajasthan and Gujarat. Saeugeteirkundliche mitteilungen 30(1): 46-48.

Balasingh, J. Suthakar-Isaac, S., and R. Subbaraj. 1993. Tent roosting by the frugivorous bat Cynopterus sphinx in southern India. Current Science 65(5):418.

Banjeree, K., Ilkal, M.A., and P.K. Deshmikh. 1984. Susceptibility of Cynopterus sphinx (frugivorus bat) and Suncus minimus (house shrew) to Japanese encephalitis virus. Indian Journal of Medical Research 79(1): 8-12.

Krishna, A. and C.J. Dominic. 1983. Growth of young and sexual maturity of 3 species of Indian Bats. Journal of Animal Morphology and Physiology 30(1-2): 162-168.

Nowak, Ronald. 1991 Walker's Mammals of the World, Fifth edition. John Hopkins University Press, Baltimore and London.

Sandhu, S. and A. Gopalakrishna. 1984. Some observations on the breeding biology of Cynopterus sphinx in central India. Current Science 53(22): 1189-1192.