Spotted-winged fruit bat (Balionycteris maculata)

Synonyms: Cynopterus maculatus
KingdomAnimalia
PhylumChordata
ClassMammalia
OrderChiroptera
FamilyPteropodidae
GenusBalionycteris (1)
SizeHead-and-body length: 53 - 62 mm (2)
Forearm length: 39 - 44 mm (2)
Weight10.0 – 16.5 g (2)

Classified as Least Concern (LC) on the IUCN Red List (1).

The smallest fruit bat in the world, this species is both charming and beautiful. Its black, dog-like face has large eyes, with a pale spot beneath each. The nostrils are long and somewhat tubular, and the ears are small. The soft fur is very dark brown on the back, and paler on the underside. Pale spots contrast with the dark wing membranes, and often highlight the joints of the finger bones. This fruit-eating bat has a claw on the second digit of each hand, enabling it to cling to fruit trees (2) and break into tough-skinned fruit with its strong jaws (3). It does not have a tail (2).

This species is found in southern Thailand, western Peninsular Malaysia, Borneo, Sumatra, and the Durian and Galang Islands (4).

Occurring mainly in forest habitats, the spotted-winged fruit bat roosts primarily in the lower canopy. It is found from the lowlands to montane forest, and prefers to roost in palm trees and ferns that grow on the trunks of large forest trees, as well as in the active nests of tree-dwelling ants, and the unoccupied tree-nests of termites (2).

Roosting in harems with one male and up to nine females and their young, the male must work to make his roost attractive to females, and then defend the area. Females may move between roosts, but males protect any females that are in his territory. The males often build tents in the tree-nests of ants and termites. It is not known how these are made, but from evidence in closely related species, it is likely that they excavate the inner regions of the nests using their teeth and claws, until a bell-shaped cavity remains (5).

Females give birth to two litters each year, usually of a single pup in each. These pups are born with their eyes and ears closed and weigh 3.5 grams, after a pregnancy lasting 135 days (5). Their mothers feed them milk for the first 40 to 80 days of their life, and once weaning has begun, the young bats will fly next to their mothers on foraging trips. They live for up to four years (5).

This bat eats the fruit of up to 22 plant species, and plays an important role in seed dispersal and plant renewal, particularly in older forests (5). Individuals do not travel far to forage; females spend the entire night foraging without returning to the roost, whereas males make several trips in order to defend and improve their roost (6).

This sensitive species relies on a deep and productive forest and constant deforestation throughout its range threatens its population stability (5). The rapid increase in land devoted to growing oil palm has resulted in extensive loss of primary forest. Together, Malaysia and Indonesia export 88% of the world’s palm oil, for use in products such as margarine, lipstick and detergent. Deforestation continues at a steady rate for conversion to agricultural land and building communities, and despite the contribution of many bats to the pollination and seed dispersal of many fruit crops, persecution of bats is also a threat (7).

Deforestation of primary forest for oil palm plantations, including within protected areas, is an issue of major concern and one that relies on both governmental action and consumer concern. Some large retailers have agreed, in collaboration with the WWF, to source products containing palm oil from plantations that are not on deforested land (7). Many scientific and charitable groups contribute to bat monitoring and local education programmes that can help to reduce persecution and raise awareness of the natural assets of the land (8).

This information is awaiting authentication by a species expert, and will be updated as soon as possible. If you are able to help please contact: arkive@wildscreen.org.uk

  1. IUCN Red List (January, 2009)
    http://www.iucnredlist.org
  2. Kingston, T. (2005) Pers. comm.
  3. Altringham, J. (2001) Bats: Biology and Behaviour. Oxford University Press, Oxford.
  4. Corbet, G.B. and Hill, J.E. (1992) The Mammals of the Indomalayan Region: a systematic review. Oxford University Press, Oxford.
  5. Lubee Bat Conservancy (December, 2005)
    http://www.lubee.org
  6. Hodginson, R., Balding, S.T., Akbar, Z. and Kunz, T.H. (2003) Roosting ecology and social organisation of the spotted-winged fruit bat, Balionycteris maculate, in a Malaysian lowland diptercarp forest. Journal of Tropical Ecology, 19: 667 - 676.
  7. Europa World (January, 2005)
    http://www.europaworld.org/issue66/swisspalm25102.htm
  8. Maltby, A. (2005) Pers. comm.