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By Erin Silbernagel
Geographic Range
Pteropus giganteus occurs in tropical regions of South Central Asia, from Pakistan to China, and as far south as the Maldive Islands. (Nowak, 1999)
Habitat
These animals can be found in forests and swamps. Large groups of individuals roost in trees such as banyan, fig, and tamarind. Roosting trees are usually in the vicinity of a body of water. ("Indian Flying Fox (Pteropus giganteus)", 2004; Marimuthu, 1998; Nowak, 1999)
These animals are found in the following types of habitat:
tropical 
.
Terrestrial Biomes:
forest ; rainforest .
Wetlands: swamp .
Physical Description
(21.12 to 56.32 oz)
(9.06 in)
(3.94 to 4.92 ft)
The physical appearance of this species is similar to that of megachiropterans in general, with large eyes, simple ears, and no facial ornamentation. Dark brown, gray, or black body color with a contrasting yellowish mantle is typical of the genus Pteropus. Body mass ranges from 600 to 1600 g and males are generally larger than females. Wingspan may range from 1.2 to 1.5 m and body length averages 23 cm. Members of the genus Pteropus maintain body temperatures between 33 and 37 C, but must do this through constant activity. (Marimuthu, 1998; Nowak, 1999; Thatcher, 2004; The Minnesota Zoo, 2002)
Some key physical features:
endothermic ; heterothermic ; bilateral symmetry .
Sexual dimorphism: male larger.
Reproduction
Mating occurs once yearly.
Mating season is between the months of July and October.
This species is polygynandrous, with no pair bonds occurring between males and females. Females are defended from intruding males by males that live in their roosting tree. (Altringham, 1996)
Mating systems:
polygynandrous (promiscuous) .
Pteropus giganteus breeds yearly, with mating occurring from July to October, and births occurring from February to May. To initiate copulation, a male will fan his wings toward a female, and persistently follow her until he is able to grip the scruff of her neck with his teeth and hold her with his thumbs. Copulation occurs for a duration of 30 to 40 seconds. The female usually vocalizes and physically resists the advances of the male during the encounter. After copulation, the male again follows the female while vocalizing loudly. Gestation period is typically 140 to 150 days, after which 1 to 2 young are born. Like other members of the genus Pteropus, the young are carried by the mother for the first few weeks of life. Sexual maturity for this species occurs at about 1.5 years of age. (Koilraj, Agoramoorthy, and Marimuthu, 2001; Nowak, 1999; Thatcher, 2004; The Minnesota Zoo, 2002)
Key reproductive features:
iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization ; viviparous .
After birth, young are carried by the mother for the first three weeks of life. They begin to hang by themselves after this time period, but are still carried to feeding sites by the mother. Young learn to fly at about 11 weeks of age and are weaned at 5 months. Males do not participate in parental care. (Nowak, 1999; The Minnesota Zoo, 2002)
Parental investment:
altricial ; pre-fertilization (provisioning, protecting: female); pre-hatching/birth (provisioning: female, protecting: female); pre-weaning/fledging (provisioning: female, protecting: female); pre-independence (protecting: female); inherits maternal/paternal territory.
Lifespan/Longevity
[External Source: Max Planck Institute for Demographic Research]
The longest lifespan of an individual of this species in captivity was recorded at 31 years, 5 months. Little information is available regarding life expectancy in the wild. (Nowak, 1999)
Behavior
Pteropus giganteus is a social species, with large groups of several hundred individuals living in the same tree. Males may maintain a vertical dominance hierarchy of resting spots in the tree, and may also defend the roost and associated females from intruders. During the day, these animals sleep, hanging upside down by their feet with their wings wrapped around themselves. They also fan themselves to aid in thermoregulation, move around in the roosting tree, and communicate with each other. As they are nocturnal, they leave the tree at sunset to feed, returning after several hours of finding food, feeding, digesting, and resting. (Marimuthu, 1998; Nowak, 1999)
Home Range
The roosting tree is the area in which Indian flying foxes spend the majority of the day. This species, as well as other large species of Pteropus, is reported to travel up to 15 km to find food. (Thatcher, 2004)
Key behaviors:
arboreal ; flies; nocturnal ; motile ; territorial ; social ; colonial ; dominance hierarchies .
Communication and Perception
Communication among individuals of this species is vocal. They chatter and squawk when threatened. Typical of megachiropterans, P. giganteus does not echolocate, and relies on sight rather than hearing for navigation. Because of their use of vision, there is probably communication involving body postures and positioning. Tactile communication is important during mating, as well as between mothers and their offspring. (Marimuthu, 1998; Thatcher, 2004)
Food Habits
Pteropus giganteus is frugivorous, as are other species of the Suborder Megachiroptera, otherwise known as the Old World fruit bats. This species has been reported to eat many different species of fruit, including guava, mango, and fig. An individual of the genus Pteropus squeezes out fruit juices from the pulp against the roof of its mouth, and then discards the dry material. Some Pteropus species also supplement their dietary protein by eating insects. Others, including P. giganteus, eat the blossoms and nectar of fruiting plants. (Marimuthu, 1998; Thatcher, 2004; The Minnesota Zoo, 2002)
Plant Foods:
fruit; nectar; flowers.
Predation
- humans (Homo sapiens)
- snakes
- raptors
Major predators of this species are humans, snakes and raptors. ("Indian Flying Fox (Pteropus giganteus)", 2004)
Ecosystem Roles
This species, along with other species of the genus Pteropus, plays a role in seed dispersal. It is also eaten by snakes and raptors. (Marimuthu, 1998)
Key ways these animals impact their ecosystem:
disperses seeds.
- little information available
- little information available
- little information available
Economic Importance for Humans: Negative
Indian flying foxes cause extensive damage to fruit orchards, and are therefore considered pests in many regions. They may also be responsible for spreading disease, particularly the Nipah virus, which causes illness and death in humans. (ICDDR,B: Centre for Health and Population Research, 2002; Kunz and Racey, 1998; Marimuthu, 1998; Thatcher, 2004)
Ways that these animals might be a problem for humans:
injures humans (carries human disease); crop pest.
Economic Importance for Humans: Positive
Humans in some regions benefit from Indian flying foxes by hunting them for food and medicinal purposes. (Marimuthu, 1998)
Ways that people benefit from these animals:
food ; source of medicine or drug .
Conservation Status
IUCN Red List: [link]:
Lower Risk - Least Concern.
US Federal List: [link]:
No special status.
CITES: [link]:
Appendix II.
This species is listed in CITES Appendix II, meaning it is not currently threatened, but could become so if protective measures are not taken.
Other Comments
Although not considered an at risk species, P. giganteus is subject to lethal, officially sanctioned control measures in many areas, including the Maldive Islands, Pakistan, and India, because of their negative effects on fruit orchards. Despite this negative impact, this species is protected and considered sacred by people in certain regions of India. (Kunz and Racey, 1998; Marimuthu, 1998; Nowak, 1999)
For More Information
Find Pteropus giganteus information at
Contributors
Erin Silbernagel (author), University of Alaska Fairbanks. Link Olson (editor, instructor), University of Alaska Fairbanks.
Nancy Shefferly (editor), Animal Diversity Web Staff.
