Pteropus alecto
black flying fox

Pteropus alecto is found in the Australian and Oriental regions of the world. It is found from tropical/subtropical Australia to Sulawesi (from 0 to 29° south latitude). (Palmer and Woinarski, 1999; Vardon and Tidemann, 1998)

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, Price, and Bach, 2000; Vardon and Tidemann, 2000)

Pteropus alecto has a black body with some lighter hairs, and a black head. These animals may have a brown eye-ring, and often have a reddish collar on the back of the neck. The legs are furred to the knee, but are hairless below. The forearm length measures 153 to 191 mm and average weight is 667g. (Thatcher, 1998; Webb and Tidemann, 1995)

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)

Pteropus alecto is a nocturnal species. During the day, P. alecto roosts in colonies called camps. Typically males will travel between roosts more than females throughout the year. However, females travel further distances from roosting sites to food than males do. During the build-up season, females will travel between roosts more than at any other times of the year. Both males and females travel further between roosting sites and food during the dry season than any other season. (Palmer and Woinarski, 1999)

Home Range

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)

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, Price, and Bach, 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 P. alecto 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, Price, and Bach, 2000)

Little information exists on predation in black flying foxes.

Because of its ability to access patchily distributed resources, P. alecto 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 Eucalyptus species in northern Australia, and it is also probably an important pollinator and seed disperser in Syzygium species. (Palmer and Woinarski, 1999; Palmer, Price, and Bach, 2000)

It is estimated that the Australian commercial fruit industry loses approximately $20 million per year to flying foxes (not just P. alecto). Because of this, P. alecto is shot as an orchard pest in many areas. It also is known to carry/contract bat 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, Kelson, and Jamieson, 1997; Vardon and Tidemann, 2000)

Throughout much of its range, P. alecto is hunted for food. (Vardon and Tidemann, 2000)

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. (CITES, 2000; IUCN, 2002; U.S. Fish and Wildlife Service, 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)