Animal Diversity Web

Geographic Range

Bulmer's fruit bats (Aproteles bulmerae) exists only as one colony of up to 160 individuals in western Papua New Guinea (Flannery 1995). (Flannery, 1995)

• Biogeographic Regions
• australian
  • native

• Other Geographic Terms
• island endemic

Habitat

Bulmer's fruit bats roost in a large, open cave known as Luplupwintem at an elevation of 2400 m (Flannery 1995). The area around the cave is a mossy montane forest composed mostly of conifers (Flannery & Seri 1993). Bulmer's fruit bats will descend to elevations lower than 1760 m in order to forage on fig trees in the mid-montane tropical forest (Bonaccorso 1998). (Bonaccorso, 1998; Flannery and Seri, 1993; Flannery, 1995)

• Habitat Regions
• tropical
• terrestrial

• Terrestrial Biomes
• forest
• mountains

• Other Habitat Features
• caves

• Range elevation

  1400 to 2400 m

  4593.18 to 7874.02 ft

Physical Description

Due to the rarity of the species, scientists have only collected three complete individuals (Flannery & Seri 1993). Bulmer's fruit bats are large, bare-backed bats, sharing this naked back with their closest relatives, members of the genus Dobsonia (Giannini & Simmons 2003). The wings meet at the midline of the back and insert at the base of the second digit of the foot (Flannery & Seri 1993). There is a short tail of approximately 30 mm and a narrow uropatagium along the legs (Bonaccorso 1998). Of the two adult females collected, the head-body lengths measured were 210 mm and 240 mm (Flannery & Seri 1993). One adult female weighed 600 g, while a juvenile male weighed 120 g (Flannery & Seri 1993). No wingspans were recorded for any specimens, although forearm lengths of adult females were 147.7 mm and 165.7 mm (Flannery & Seri 1993). Bulmer's fruit bats are covered by dark brown hair on the head and rump (Flannery 1995). Fine brown hairs cover the ventral surface, interspersed with longer silvery ones. The mantle is paler and whitish, but surrounded by a margin of dense, brown fur. Sexual dimorphism is not noted, but this may be due to a lack of data. The forearm and tibia are mostly naked (Flannery & Seri 1993). On the second digit of the wing, there is a brown and well-developed claw. Bulmer's fruit bats are most easily distinguished from all other bats by the complete lack of upper and lower incisors. The dental formula is 0/0, 1/1, 2/3, 2/3 = 24 (Bonaccorso 1998). (Bonaccorso, 1998; Flannery and Seri, 1993; Flannery, 1995; Giannini and Simmons, 2003)

• Other Physical Features
• endothermic
• homoiothermic
• bilateral symmetry

Reproduction

The mating system of Bulmer's fruit bats is unknown due to lack of data. Bats, in general, have a wide range of mating behaviors including monogamy, polygyny, and multimale groups (Altringham 2011). In the genus Pteropus, colonial species are often polygynous (Pierson & Rainey 1992). Bulmer's fruit bats, therefore, may be polygynous, although more research is needed. (Altringham, 2011; Pierson and Rainey, 1992)

Although little is known of the reproductive behavior of Bulmer's fruit bats, breeding is suspected to be seasonal, with births occurring in April (Flannery & Seri 1993, p. 23). Litter size is likely one young per litter per year, similar to Dobsonia magna and flying foxes in the genus Pteropus (Flannery 1995; Pierson & Rainey 1992). (Flannery and Seri, 1993; Flannery, 1995; Pierson and Rainey, 1992)

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

• Breeding interval

  Aproteles bulmerae likely breeds once yearly.

• Breeding season

  Although the mating season of Aproteles bulmerae is unknown, it is likely during the months of November and December.

• Average number of offspring

  1

Young are dependent on the mother for the first weeks of life and have been observed attached to the female while she forages (Flannery & Seri, 1993). In the genus Pteropus, the young must cling to the mother for warmth during the first few weeks, until they develop more fur, but are eventually left behind while the mother forages (Pierson & Rainey, 1992). Bulmer's fruit bats also probably carry their young for warmth, as a mother was observed with a juvenile while foraging (Flannery & Seri, 1993). (Flannery and Seri, 1993; Pierson and Rainey, 1992)

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

Lifespan/Longevity

The lifespan of Bulmer's fruit bats in the wild is unknown and an individual has never been taken into captivity. Bats tend to live 3.5 times longer than similarly sized non-flying mammals (Wilkinson and South, 2002). The maximum life expectancy of a comparatively sized flying fox in the genus Pteropus is over 31 years in captivity (Pierson & Rainey, 1992). (Pierson and Rainey, 1992; Wilkinson and South, 2002)

Behavior

Bulmer's fruit bats forage for fruit nocturnally, roosting in a cave socially during the day. Behavior at Luplupwintem cave has only been observed once over a period of three days and nights. In the presence of humans, a few sentinels will leave the cave around dusk, emitting calls for 5 to 10 minutes, before the rest of the individuals leave the cave (Flannery & Seri, 1993). The colony returns to the roost before daylight (Flannery, 1995). As only the exterior of the cave was observed, it is unclear if the whole colony leaves to forage or if some individuals stay behind. (Flannery and Seri, 1993; Flannery, 1995)

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

Home Range

Bulmer's fruit bats can fly considerable distances from the roost in order to forage for food (Flannery, 1995). Scientists observed an adult female carrying a juvenile feeding 32 km from the roost site (Flannery, 1995). Other colonial bats can travel from 15 to 50 km to commute to their foraging areas (Bonaccorso et al., 2002). (Bonaccorso, et al., 2002; Flannery, 1995)

Communication and Perception

Bulmer's fruit bats have been observed communicating vocally, emitting a bird-like call (Flannery & Seri, 1993). Like the majority of megachiropterans, Bulmer's fruit bats rely on sight and smell for navigation and locating food sources (Mickleburgh et al., 1992). (Flannery and Seri, 1993; Mickleburgh, et al., 1992)

• Communication Channels
• acoustic
• chemical

• Perception Channels
• visual
• tactile
• acoustic
• chemical

Food Habits

Bulmer's fruit bats are likely obligate frugivores and have been observed feeding on figs (Ficus) (Flannery & Seri, 1993). They travel significant distances away from the cave roost to access these fruits (Flannery, 1995). (Flannery and Seri, 1993; Flannery, 1995)

• Primary Diet
• herbivore
  • frugivore

• Plant Foods
• fruit

Predation

Bulmer's fruit bats have no known predators, apart from humans.

• Anti-predator Adaptations
• cryptic

• Known Predators

  • humans (Homo sapiens)

Ecosystem Roles

As frugivores, Bulmer's fruit bats disperse seeds (Pierson & Rainey, 1992). Assuming the seeds are not damaged in the act of ingestion, Bulmer's fruit bats disperse seeds in their feces as they travel to and from foraging grounds and roosts (Altringham, 2011). (Altringham, 2011; Pierson and Rainey, 1992)

• Ecosystem Impact
• disperses seeds
• pollinates

Economic Importance for Humans: Positive

The local population in Papua New Guinea hunts Bulmer's fruit bats and other large fruit bats as a source of protein (Flannery, 1995; Mickleburgh et al., 2009). Around 1975, villagers acquired ropes and shotguns, which allowed them to enter caves and hunt bats in greater numbers (Flannery & Seri, 1993). Before the advent of modern technology, villagers were limited in their ability to hunt large fruit bats by the cave's inaccessibility and the difficulty of hunting with a bow and arrow (Flannery & Seri, 1993). (Flannery and Seri, 1993; Flannery, 1995; Mickleburgh, et al., 2009)

• Positive Impacts
• food

Economic Importance for Humans: Negative

There are no known adverse effects of Bulmer's fruit bats on humans.

Conservation Status

Bulmer's fruit bats are listed as critically endangered on the IUCN Red List. They are at risk due to their narrow endemic range, low birth rate per individual, and hunting pressure (Bonaccorso, 1998). Their habitat is currently not protected and there is no active plan for the conservation of this species (Hutson et al., 2008). (Bonaccorso, 1998; Hutson, et al., 2008)

• IUCN Red List

  Critically Endangered

• US Federal List

  No special status

• CITES

  No special status

Other Comments

Bulmer's fruit bats were assumed to be extinct after their initial description from fossil remains by J.I. Menzies in 1977 (Menzies, 1977). In 1980, the species was confirmed to still exist when two skulls were identified as Bulmer's fruit bat (Hyndman & Menzies 1980). Unbeknownst to scientists, locals were aware of a large colony of thousands of individuals prior to 1975 (Flannery & Seri, 1993). Hunters decimated the colony in 1975. When scientists visited Luplupwintem cave in 1977, they observed only two individuals (Flannery & Seri, 1993). In the most recent visits in 1992 and 1993, scientists counted 137 and 160 individuals, respectively, leaving the cave (Flannery & Seri, 1993; Flannery, 1995). (Flannery and Seri, 1993; Flannery, 1995; Hyndman and Menzies, 1980; Menzies, 1977)

Contributors

Nicholas Peterson (author), Yale University, Eric Sargis (editor), Yale University, Tanya Dewey (editor), University of Michigan-Ann Arbor.

References

Altringham, J. 2011. Bats: from Evolution to Conservation. New York, NY: Oxford University Press.

Bonaccorso, F. 1998. Bats of Papua New Guinea. Washington, D.C.: Conservation International.

Bonaccorso, F., J. Winkelmann, E. Dumont, K. Thibault. 2002. Home Range of Dobsonia minor (Pteropodidae): A Solitary, Foliage-roosting Fruit Bat in Papua New Guinea. Biotropica, 34: 127-135.

Flannery, T. 1995. Mammals of New Guinea. Ithaca, NY: Comstock/Cornell.

Flannery, T., L. Seri. 1993. Rediscovery of Aproteles bulmerae (Chiroptera: Pteropodidae). Morphology, ecology and conservation. Mammalia, 57: 19-25.

Giannini, N., N. Simmons. 2003. A phylogeny of megachiropteran bats (Mammalia: Chiroptera: Pteropodidae) based on direct optimization analysis of one nuclear and four mitochondrial genes. Cladistics, 19: 496-511.

Hutson, T., K. Helgen, T. Flannery, D. Wright. 2008. "Aproteles bulmerae Version 2013.2" (On-line). IUCN 2013. IUCN Red List of Threatened Species. Accessed December 13, 2013 at http://www.iucnredlist.org/.

Hyndman, D., J. Menzies. 1980. Aproteles bulmerae (Chiroptera:Pteropodidae) of New Guinea Is Not Extinct. Journal of Mammology, 61: 159-160.

Menzies, J. 1977. Fossil and Subfossil Fruit Bats from the Mountains of New Guinea. Australian Journal of Zoology, 25: 329-336.

Mickleburgh, S., A. Hutson, P. Racey. 1992. Old World fruit bats: an action plan for their conservation. Gland, Switzerland: IUCN.

Mickleburgh, S., K. Waylen, P. Racey. 2009. Bats as bushmeat: a global review. Oryx, 43(2): 217-234.

Pierson, E., W. Rainey. 1992. The Biology of Flying Foxes of the Genus Pteropus: A Review. Pacific Island Flying Foxes: Proceedings of an International Conservation Conference, 90: 1-17.

Wilkinson, G., J. South. 2002. Life history, ecology and longevity in bats. Aging Cell, 1: 124-131.