In Australia, black flying foxes are found in the subtropical and tropical latitudes, primarily in the coastal areas of the northern territory and as far as 250 km inland. Their habitat consists of rainforest, eucalyptus open forest, and savanna woodland. They roost primarily in bamboo, rainforests, and mangroves. However, there have been a few known roosting sites in caves and overhangs. Palmer and Woinarski (1999) found that, during the cooler dry season months, 74% of black flying foxes roosted in bamboo, 20% in mangroves, and 6% in rainforest habitats. During the build-up season (characterized by warming temperatures and early rains), 68% roosted in rainforest, 17% roosted in mangroves, and 15% roosted in bamboo. During the wet season, 52% roosted in rainforest, 28% in bamboo, and 20% roosted in mangroves. (Palmer and Woinarski, 1999)
Black flying foxes roosting in bamboo thickets roost 12 to 16 m off the ground, space themselves less than 1 m apart, and forage predominantly in woodland habitat. Those roosting in rainforests roost more than 18 m off the ground, space themselves approximately 1 m apart, and forage predominantly in forest and rainforest habitat dominated by Melaleuca species. Females use camps more than males, and smaller camps tend to be primarily made up of males and sub-adults. (Palmer and Woinarski, 1999; Palmer, et al., 2000; Vardon and Tidemann, 2000)
- Other Habitat Features
- Sexual Dimorphism
- sexes alike
- Average mass
- 667 g
- 23.51 oz
Little information exists on mating systems in black flying foxes.
Peak birth times are correlated with periods of maximal plant productivity, hence, the timing of births varies with location. In Brisbane, Australia, most births are in October to November. In the northern territory of Australia, peak birth times are from January to March, and births in November are unusual but not rare. (Vardon and Tidemann, 1998; Vardon and Tidemann, 2000)
It takes females 14.8 to 17 months and males 16.3 to 18 months to reach adult size. Females tend to grow faster than males. On average, females gain 2.56 g/day and their forearms grow 0.25 mm/day. On average, males gain 2.28 g/day and their forearms grow 0.15 mm/day. (Vardon and Tidemann, 1998; Vardon and Tidemann, 2000)
- Key Reproductive Features
- seasonal breeding
- gonochoric/gonochoristic/dioecious (sexes separate)
- Breeding interval
- These bats appear to breed annually.
- Breeding season
- The breeding and therefore birthing seasons vary with geography, and are timed so that births occur during the time of maximum fruit productivity.
- Average number of offspring
Little information exists on parental care in black flying foxes. As mammals, it is likely that females play the largest role in parental care. They provide offspring with protection and nourishment until they are independent and weaned. However, beyond that basic speculation, information is not available.
- Parental Investment
- no parental involvement
It is unknown how long black flying foxes live, however, it has been estimated that the females which survive to maturity would need to live about 7 years to maintain a stable population. Approximately 30 % of females born survive to maturity, compared to 37% in males. Survival rates vary between camps and between years. In years in which food is more abundant, lower levels of mortality are expected. (Vardon and Tidemann, 2000)
- Range lifespan
- 4.5 (high) years
- Range lifespan
- Average lifespan
- 19.7 years
- Average lifespan
Palmer and Woinarski found that males travel an average of 6.8 km, and females travel an average of 5.8 km between roosts. On average, when foraging at night, males will travel 6.2 km and females will travel 10.9 km from their roosts. (Palmer and Woinarski, 1999)
Communication and Perception
Little information exists on communication in black flying foxes. However, as mammals, they are likely to use visual signals, tactile communication, scent information, and vocalizations.
Black flying foxes are dietary generalists known to feed on fruits, pollen, and nectar of 23 rainforest species. These species include Carpentaria acuminata, Terminalia microcarpa, Diospyros littorea, Elaeocarpus arnhemicus, Ficus opposita, Ficus racemosa, Ficus scobina, Ficus virens, Eucalyptus miniata, Eucalyptus papuana, Eucalyptus polycarpa, Eucalyptus tetrodonta, Lophostemon grandiflorus, Lophostemon lactifluus, Melaleuca dealbata, Melaleuca viridiflora, Syzygium nervosum, Passiflora foetida, Grevillea pteridifolia, Nauclea orientalis, Timonius timon, Cupaniopsis anacardioides, and Gmelina schlechteri. (Palmer and Woinarski, 1999; Palmer, et al., 2000)
Black flying foxes forage on different resources depending upon the time of year. During the dry season, they forage primarily in Eucalyptus open forest. During the build-up season, they forage primarily in the Melaleuca open forest, and during the wet season, they forage primarily in rainforest. It has been suggested that selects sites that are richer in resources than floristically similar sites, which suggests that apparently similar habitats are actually different in resource abundance. (Palmer and Woinarski, 1999; Palmer, et al., 2000)
- Plant Foods
Little information exists on predation in black flying foxes.
Because of its ability to access patchily distributed resources, Eucalyptus species in northern Australia, and it is also probably an important pollinator and seed disperser in Syzygium species. (Palmer and Woinarski, 1999; Palmer, et al., 2000)probably plays an important role in connecting isolated fragments of rainforest by transporting seeds and pollen between feeding sites. It is probably an important pollinator of 2
- Ecosystem Impact
- disperses seeds
Economic Importance for Humans: Positive
Throughout much of its range, (Vardon and Tidemann, 2000)is hunted for food.
- Positive Impacts
Economic Importance for Humans: Negative
It is estimated that the Australian commercial fruit industry loses approximately $20 million per year to flying foxes (not just Lyssavirus, which is similar to the rabies virus and can be contracted by humans. However, it is not known how easily Lyssavirus is transmitted to humans or other mammals. (Tidemann , et al., 1997; Tidemann, et al., 1997; Vardon and Tidemann, 2000)). Because of this, is shot as an orchard pest in many areas. It also is known to carry/contract bat
- Negative Impacts
- crop pest
- causes or carries domestic animal disease
Pteropus alecto is currently listed under CITES appendix II and is not mentioned on the IUCN Red List or the U.S. Endangered Species Act. ("IUCN Red List of Threatened Species", 2002; "CITES Official Documents. Appendices I and II", 2000; "Endangered and Threatened Wildlife and Plants", 1999)
There have been some individuals that appear to be hybrids between black flying foxes and grey-headed flying foxes (Pteropus poliocephalus). These individuals had characteristics of both parent species, however, genetic testing of these hybrids failed to confirm that they were hybrids. The authors note that further testing needs to be done to conclude whether or not these individuals are actually hybrids. (Webb and Tidemann, 1995)
Nancy Shefferly (editor), Animal Diversity Web.
Diane Ten Pas (author), University of Wisconsin-Stevens Point, Chris Yahnke (editor), University of Wisconsin-Stevens Point.
Living in Australia, New Zealand, Tasmania, New Guinea and associated islands.
uses sound to communicate
Referring to an animal that lives in trees; tree-climbing.
- 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.
- causes or carries domestic animal disease
either directly causes, or indirectly transmits, a disease to a domestic animal
uses smells or other chemicals to communicate
used loosely to describe any group of organisms living together or in close proximity to each other - for example nesting shorebirds that live in large colonies. More specifically refers to a group of organisms in which members act as specialized subunits (a continuous, modular society) - as in clonal organisms.
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.
union of egg and spermatozoan
A substance that provides both nutrients and energy to a living thing.
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
an animal that mainly eats fruit
An animal that eats mainly plants or parts of plants.
offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).
makes seasonal movements between breeding and wintering grounds
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.
an animal that mainly eats nectar from flowers
active during the night
- oceanic islands
islands that are not part of continental shelf areas, they are not, and have never been, connected to a continental land mass, most typically these are volcanic islands.
found in the oriental region of the world. In other words, India and southeast Asia.
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.
Referring to something living or located adjacent to a waterbody (usually, but not always, a river or stream).
- seasonal breeding
breeding is confined to a particular season
reproduction that includes combining the genetic contribution of two individuals, a male and a female
a wetland area that may be permanently or intermittently covered in water, often dominated by woody vegetation.
uses touch to communicate
Living on the ground.
the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.
uses sight to communicate
reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.
CITES. 2000. "CITES Official Documents. Appendices I and II" (On-line ). Accessed 12/03/02 at http://www.cites.org/eng/append/I_II.shtml.
U.S. Fish and Wildlife Service. 1999. "Endangered and Threatened Wildlife and Plants" (On-line ). Accessed 12/03/2002 at http://endangered.fws.gov/wildlife.html#Species.
IUCN. 2002. "IUCN Red List of Threatened Species" (On-line ). Accessed 12/03/2002 at http://www.redlist.org/.
Palmer, C., O. Price, C. Bach. 2000. Foraging ecology of the black flying fox (Pteropus alecto) in the seasonal tropics of the Northern Territory, Australia. Wildlife Research, 27: 169-178.
Palmer, C., J. Woinarski. 1999. Seasonal roosts and foraging movements of the black flying fox (Pteropus alecto) in the Northern Territory: resource tracking in a landscape mosiac. Wildlife Research, 26: 823-838.
Thatcher, O. 1998. "Pteropus alecto" (On-line ). Accessed 12/03/02 at http://www.biology.leeds.ac.uk/staff/dawa/bats/Fruitbats/ALECTO.HTML.
Tidemann , C., M. Vardon, J. Nelson, R. Speare, L. Gleeson. 1997. Health and conservation implications of Australian bat Lyssavirus. Australian Zoologist, 30: 369-376.
Tidemann, C., S. Kelson, G. Jamieson. 1997. Flying-fox damage to orchard fruit in Australia - incidence, extent and economic impact. Australian Biologist, 10: 177-184.
Vardon, M., C. Tidemann. 1998. Reproduction, growth and maturity in the black flying-fox, Pteropus alecto (Megachiroptera: Pteropodidae). Australian Journal of Zoology, 46: 329-344.
Vardon, M., C. Tidemann. 2000. The black flying-fox (Pteropus alecto) in north Australia: juvenile mortality and longevity. Australian Journal of Zoology, 48: 91-97.
Webb, N., C. Tidemann. 1995. Hybridization between black (Pteropus alecto) and grey-headed (P. poliocephalus) flying-foxes (Megachiroptera: Pteropodidae). Australian Mammology, 18: 19-26.