Product Code Database
Megabats constitute the family Pteropodidae of the order Chiroptera. They are also called fruit bats, Old World fruit bats, or—especially the genus Acerodon and Pteropus—Pteropus. They are the only member of the superfamily Pteropodoidea, which is one of two superfamilies in the suborder Yinpterochiroptera. Internal divisions of Pteropodidae have varied since Subfamily were first proposed in 1917. From three subfamilies in the 1917 classification, six are now recognized, along with various tribes. As of 2018, 197 species of megabat had been described.
The leading theory of the evolution of megabats has been determined primarily by genetic data, as the fossil record for this family is the most fragmented of all bats. They likely evolved in Australasia, with the common ancestor of all living pteropodids existing approximately 31 million years ago. Many of their lineages probably originated in Melanesia, then dispersed over time to mainland Asia, the Mediterranean, and Africa. Today, they are found in tropical and subtropical areas of Eurasia, Africa, and Oceania.
The megabat family contains the largest bat species, with individuals of some species weighing up to and having wingspans up to . Not all megabats are large-bodied; nearly a third of all species weigh less than . They can be differentiated from other bats due to their dog-like faces, clawed second digits, and reduced uropatagium. A small number of species have tails. Megabats maintain high metabolic rates and have several adaptations for flight, including rapid rates of oxygen consumption (VO2), the ability to sustain of more than 700 beats per minute, and large lung volumes.
Most megabats are nocturnal or crepuscular, although a few species are active during the daytime. During the period of inactivity, they roost in trees or caves. Members of some species roost alone, while others form colonies of up to a million individuals. During the period of activity, they use flight to travel to food resources. With few exceptions, they are unable to echolocate, relying instead on keen senses of sight and smell to navigate and locate food. Most species are primarily frugivore and several are nectarivore. Other less common food resources include leaves, pollen, twigs, and bark.
They reach sexual maturity slowly and have a low reproductive output. Most species have one offspring at a time after a pregnancy of four to six months. This low reproductive output means that after a population loss their numbers are slow to rebound. A quarter of all species are listed as threatened, mainly due to habitat destruction and overhunting. Megabats are a popular food source in some areas, leading to population declines and extinction. They are also of interest to those involved in public health as they are natural reservoirs of several viruses that can affect humans.
In 1875, the zoologist George Edward Dobson was the first to split the order Chiroptera (bats) into two : Megachiroptera (sometimes listed as Macrochiroptera) and Microchiroptera, which are commonly abbreviated to megabats and microbats. Dobson selected these names to allude to the body size differences of the two groups, with many fruit-eating bats being larger than insect-eating bats. Pteropodidae was the only family he included within Megachiroptera.
A 2001 study found that the dichotomy of megabats and microbats did not accurately reflect their evolutionary relationships. Instead of Megachiroptera and Microchiroptera, the study's authors proposed the new suborders Yinpterochiroptera and Yangochiroptera. This classification scheme has been verified several times subsequently and remains widely supported as of 2019. Since 2005, this suborder has alternatively been called "Pteropodiformes". Yinpterochiroptera contained species formerly included in Megachiroptera (all of Pteropodidae), as well as several families formerly included in Microchiroptera: Megadermatidae, Rhinolophidae, Nycteridae, Craseonycteridae, and Rhinopomatidae. Two superfamilies comprise Yinpterochiroptera: Rhinolophoidea—containing the above families formerly in Microchiroptera—and Pteropodoidea, which only contains Pteropodidae.
In 1917, Danish mammalogist Knud Andersen divided Pteropodidae into three subfamilies: Macroglossinae, Pteropinae (corrected to Pteropodinae), and Harpyionycterinae. A 1995 study found that Macroglossinae as previously defined, containing the genera Eonycteris, Notopteris, Macroglossus, Syconycteris, Melonycteris, and Megaloglossus, was paraphyly, meaning that the subfamily did not group all the descendants of a common ancestor. Subsequent publications consider Macroglossini as a tribe within Pteropodinae that contains only Macroglossus and Syconycteris. Eonycteris and Melonycteris are within other tribes in Pteropodinae, Megaloglossus was placed in the tribe Myonycterini of the subfamily Rousettinae, and Notopteris is of uncertain placement.
Other subfamilies and tribes within Pteropodidae have also undergone changes since Andersen's 1917 publication. In 1997, the pteropodids were classified into six subfamilies and nine tribes based on their morphology, or physical characteristics. A 2011 genetic study concluded that some of these subfamilies were paraphyletic and therefore they did not accurately depict the relationships among megabat species. Three of the subfamilies proposed in 1997 based on morphology received support: Cynopterinae, Harpyionycterinae, and Nyctimeninae. The other three recovered in this study consisted of Macroglossini, Epomophorinae + Rousettini, and Pteropodini + Melonycteris. A 2016 genetic study focused only on African pteropodids (Harpyionycterinae, Rousettinae, and Epomophorinae) also challenged the 1997 classification. All species formerly included in Epomophorinae were moved to Rousettinae, which was subdivided into additional tribes. The genus Eidolon, formerly in the tribe Rousettini of Rousettinae, was moved to its own subfamily, Eidolinae.
In 1984, an additional pteropodid subfamily, Propottininae, was proposed, representing one extinct species described from a fossil discovered in Africa, Propotto leakeyi. In 2018 the fossils were reexamined and determined to represent a lemur. As of 2018, there were 197 described species of megabat, around a third of which are flying foxes of the genus Pteropus.
Both echolocation and Bat flight are energetically expensive processes separately, although no increase in flight energy expenditure was found for two species of echolocating bats compared with other bats and birds . Echolocating bats couple sound production with the mechanisms engaged for flight, allowing them to reduce the additional energy burden of echolocation. Instead of pressurizing a bolus of air for the production of sound, laryngeally echolocating bats likely use the force of the downbeat of their wings to pressurize the air, cutting energetic costs by synchronizing wingbeats and echolocation. The loss of echolocation (or conversely, the lack of its evolution) may be due to the uncoupling of flight and echolocation in megabats. The larger average body size of megabats compared to echolocating bats suggests a larger body size disrupts the flight-echolocation coupling and made echolocation too energetically expensive to be conserved in megabats.
Family Pteropodidae
Megabats can be distinguished from microbats in appearance by their dog-like faces, by the presence of claws on the second digit (see Megabat#Postcrania), and by their simple ears. The simple appearance of the ear is due in part to the lack of tragi (cartilage flaps projecting in front of the ear canal), which are found in many microbat species. Megabats of the genus Nyctimene appear less dog-like, with shorter faces and tubular nostrils. A 2011 study of 167 megabat species found that while the majority (63%) have fur that is a uniform color, other patterns are seen in this family. These include countershading in four percent of species, a neck band or mantle in five percent of species, stripes in ten percent of species, and spots in nineteen percent of species.
Unlike microbats, megabats have a greatly reduced uropatagium, which is an expanse of flight membrane that runs between the hind limbs. Additionally, the tail is absent or greatly reduced, with the exception of Notopteris species, which have a long tail. Most megabat wings insert laterally (attach to the body directly at the sides). In Dobsonia species, the wings attach nearer the spine, giving them the common name of "bare-backed" or "naked-backed" fruit bats.
Megabat species have relatively small incisors and large canines. The premolars and molars are adapted to crush and pierce fruit, their primary food source.Berkovitz, B., & Shellis, P. (2018). The teeth of mammalian vertebrates. Academic Press.
The most complete dental formula is: I2/2, C 1/1, P3/3, M2/3 x 2 = 34.Giannini, N. P., Wible, J. R., & Simmons, N. B. (2006). On the cranial osteology of chiroptera. I. Pteropus (Megachiroptera: Pteropodidae). Bulletin of the American Museum of Natural History, 2006(295), 1-134. The dental formula of 34 teeth is a homologous trait for megabats. The total number of teeth varies among megabat species, and can range from 24 to 34. For example, some species of megabats have only 2 molars on either side of the lower jaw instead of 3. Others may lack one or more pairs of incisors on the upper or lower jaw.
All megabats have two to four each of upper and lower , with the exception Bulmer's fruit bat ( Aproteles bulmerae), which completely lacks incisors, and the São Tomé collared fruit bat ( Myonycteris brachycephala), which has two upper and three lower incisors. This makes it the only mammal species with an asymmetrical dental formula.
All species have two upper and lower canine tooth. The number of is variable, with four or six each of upper and lower premolars. The first upper and lower molars are always present, meaning that all megabats have at least four molars. The remaining molars may be present, present but reduced, or absent. Megabat molars and premolars are simplified, with a reduction in the cusps and ridges resulting in a more flattened crown.
Like most mammals, megabats are diphyodont, meaning that the young have a set of deciduous teeth (milk teeth) that falls out and is replaced by permanent teeth. For most species, there are 20 deciduous teeth. As is typical for mammals, the deciduous set does not include molars.
While microbats only have claws on the of their forelimbs, most megabats have a clawed second digit as well; only Eonycteris, Dobsonia, Notopteris, and Neopteryx lack the second claw. (1999). 9780801857898, JHU Press. ISBN 9780801857898 The first digit is the shortest, while the third digit is the longest. The second digit is incapable of flexion. Megabats' thumbs are longer relative to their forelimbs than those of microbats.
Megabats' hindlimbs have the same skeletal components as humans. Most megabat species have an additional structure called the calcar, a cartilage spur arising from the calcaneus. Some authors alternately refer to this structure as the uropatagial spur to differentiate it from microbats' calcars, which are structured differently. The structure exists to stabilize the uropatagium, allowing bats to adjust the camber of the membrane during flight. Megabats lacking the calcar or spur include Notopteris, Syconycteris, and Harpyionycteris. The entire leg is rotated at the hip compared to normal mammal orientation, meaning that the knees face posteriorly. All five digits of the foot flex in the direction of the sagittal plane, with no digit capable of flexing in the opposite direction, as in the feet of perching birds.
Megabats have rapid digestive systems, with a gut transit time of half an hour or less. The digestive system is structured to a herbivorous diet sometimes restricted to soft fruit or nectar. The length of the digestive system is short for a herbivore (as well as shorter than those of insectivorous microchiropterans), as the fibrous content is mostly separated by the action of the palate, tongue, and teeth, and then discarded. Many megabats have U-shaped stomachs. There is no distinct difference between the small and large intestine, nor a distinct beginning of the rectum. They have very high densities of intestinal microvillus, which creates a large surface area for the absorption of nutrients. (2025). 9783110560671, Walter de Gruyter GmbH & Co KG. ISBN 9783110560671
At high brightness levels, megabat visual acuity is poorer than that of humans; at low brightness it is superior. One study that examined the eyes of some Rousettus, Epomophorus, Eidolon, and Pteropus species determined that the first three genera possess a tapetum lucidum, a reflective structure in the eyes that improves vision at low light levels, while the Pteropus species do not. All species examined had with both and , but only the Pteropus species had S-cones, which detect the shortest wavelengths of light; because the spectral tuning of the was not discernible, it is unclear whether the S-cones of Pteropus species detect blue or ultraviolet light. Pteropus bats are Dichromacy, possessing two kinds of cone cells. The other three genera, with their lack of S-cones, are Monochromacy, unable to see color. All genera had very high densities of rod cells, resulting in high sensitivity to light, which corresponds with their nocturnal activity patterns. In Pteropus and Rousettus, measured rod cell densities were 350,000–800,000 per square millimeter, equal to or exceeding other nocturnal or crepuscular animals such as the house mouse, domestic cat, and domestic rabbit.
The litter size of all megabats is usually one. There are scarce records of twins in the following species: Madagascan flying fox ( Pteropus rufus), Dobson's epauletted fruit bat ( Epomops dobsoni), the gray-headed flying fox, the black flying fox ( Pteropus alecto), the spectacled flying fox ( Pteropus conspicillatus), the greater short-nosed fruit bat, Peters's epauletted fruit bat ( Epomophorus crypturus), the hammer-headed bat, the straw-colored fruit bat, the little collared fruit bat ( Myonycteris torquata), the Egyptian fruit bat, and Leschenault's rousette ( Rousettus leschenaultii). In the cases of twins, it is rare that both offspring survive. Because megabats, like all bats, have low reproductive rates, their populations are slow to recover from declines. (2025). 9780199207114, Oxford University Press. ISBN 9780199207114
At birth, megabat offspring are, on average, 17.5% of their mother's post-partum weight. This is the smallest offspring-to-mother ratio for any bat family; across all bats, newborns are 22.3% of their mother's post-partum weight. Megabat offspring are not easily categorized into the traditional categories of altricial (helpless at birth) or precocial (capable at birth). Species such as the greater short-nosed fruit bat are born with their eyes open (a sign of precocial offspring), whereas the Egyptian fruit bat offspring's eyes do not open until nine days after birth (a sign of altricial offspring).
As with nearly all bat species, males do not assist females in parental care. The young stay with their mothers until they are Weaning; how long weaning takes varies throughout the family. Megabats, like all bats, have relatively long nursing periods: offspring will nurse until they are approximately 71% of adult body mass, compared to 40% of adult body mass in non-bat mammals. Species in the genus Micropteropus wean their young by seven to eight weeks of age, whereas the Indian flying fox ( Pteropus medius) does not wean its young until five months of age. Very unusually, male individuals of two megabat species, the Bismarck masked flying fox ( Pteropus capistratus) and the Dayak fruit bat ( Dyacopterus spadiceus), have been observed male lactation, but there has never been an observation of a male nursing young. It is unclear if the lactation is functional and males actually nurse pups or if it is a result of stress or malnutrition.
Megabat social behavior includes using sexual behaviors for more than just reproduction. Evidence suggests that female Egyptian fruit bats take food from males in exchange for sex. Paternity tests confirmed that the males from which each female scrounged food had a greater likelihood of fathering the scrounging female's offspring. Homosexual fellatio has been observed in at least one species, the Bonin flying fox ( Pteropus pselaphon). This same-sex fellatio is hypothesized to encourage colony formation of otherwise-antagonistic males in colder climates.
Megabats are mostly nocturnal and crepuscular, though some have been observed flying during the day. A few island species and subspecies are diurnality, hypothesized as a response to a lack of predators. Diurnal taxa include a subspecies of the black-eared flying fox ( Pteropus melanotus natalis), the Mauritian flying fox ( Pteropus niger), the Caroline flying fox ( Pteropus molossinus), a subspecies of Pteropus pelagicus ( P. p. insularis), and the Seychelles fruit bat ( Pteropus seychellensis).
Megabats fly to roosting and foraging resources. They typically fly straight and relatively fast for bats; some species are slower with greater maneuverability. Species can commute in a night. animal migration of the genera Eidolon, Pteropus, Epomophorus, Rousettus, Myonycteris, and Nanonycteris can migrate distances up to . Most megabats have below-average aspect ratios, which is measurement relating wingspan and wing area. Wing loading, which measures weight relative to wing area, is average or higher than average in megabats.
Megabats are the hosts of several parasite taxa. Known parasites include Nycteribiidae and Streblidae species ("bat flies"), as well as Acari of the genus Demodex. Blood parasites of the family Haemoproteidae and intestinal nematodes of Toxocaridae also affect megabat species.
Outside of Southeast Asia, megabats have relatively low species richness in Asia. The Egyptian fruit bat is the only megabat whose range is mostly in the Palearctic realm; it and the straw-colored fruit bat are the only species found in the Middle East. The northernmost extent of the Egyptian fruit bat's range is the northeastern Mediterranean. In East Asia, megabats are found only in China and Japan. In China, only six species of megabat are considered resident, while another seven are present marginally (at the edge of their ranges), questionably (due to possible misidentification), or as accidental migrants. Four megabat species, all Pteropus, are found on Japan, but none on its five main islands. In South Asia, megabat species richness ranges from two species in the Maldives to thirteen species in India. Megabat species richness in Southeast Asia is as few as five species in the small country of Singapore and seventy-six species in Indonesia. Of the ninety-eight species of megabat found in Asia, forest is a habitat for ninety-five of them. Other habitat types include human-modified land (66 species), caves (23 species), savanna (7 species), shrubland (4 species), rocky areas (3 species), grassland (2 species), and desert (1 species).
In Australia, five genera and eight species of megabat are present. These genera are Pteropus, Syconycteris, Dobsonia, Nyctimene, and Macroglossus. Pteropus species of Australia are found in a variety of habitats, including mangrove-dominated forests, , and the wet sclerophyll forests of the Australian bush. Australian Pteropus are often found in association with humans, as they situate their large colonies in urbanization, particularly in May and June when the greatest proportions of Pteropus species populations are found in these urban colonies.
In Oceania, the countries of Palau and Tonga have the fewest megabat species, with one each. Papua New Guinea has the greatest number of species with thirty-six. Of the sixty-five species of Oceania, forest is a habitat for fifty-eight. Other habitat types include human-modified land (42 species), caves (9 species), savanna (5 species), shrubland (3 species), and rocky areas (3 species). An estimated nineteen percent of all megabat species are endemism to a single island; of all bat families, only Myzopodidae—containing two species, both single-island endemics—has a higher rate of single-island endemism.
In Guam, consumption of the Mariana fruit bat exposes locals to the neurotoxin beta-Methylamino-L-alanine (BMAA) which may later lead to neurodegenerative diseases. BMAA may become particularly Biomagnification in humans who consume flying foxes; flying foxes are exposed to BMAA by eating cycad fruits.
Species that have tested positive for the presence of EBOV include Franquet's epauletted fruit bat ( Epomops franqueti), the hammer-headed fruit bat, and the little collared fruit bat. Additionally, antibody against EBOV have been found in the straw-colored fruit bat, Gambian epauletted fruit bat ( Epomophorus gambianus), Peters's dwarf epauletted fruit bat ( Micropteropus pusillus), Veldkamp's dwarf epauletted fruit bat ( Nanonycteris veldkampii), Leschenault's rousette, and the Egyptian fruit bat. Much of how humans contract the Ebola virus is unknown. Scientists hypothesize that humans initially become infected through contact with an infected animal such as a megabat or non-human primate. Megabats are presumed to be a natural reservoir of the Ebola virus, but this has not been firmly established. Microbats are also being investigated as the reservoir of the virus, with the greater long-fingered bat ( Miniopterus inflatus) once found to harbor a fifth of the virus's genome (though not testing positive for the actual virus) in 2019. Due to the likely association between Ebola infection and "hunting, butchering and processing meat from infected animals", several West African countries banned bushmeat (including megabats) or issued warnings about it during the 2013–2016 epidemic; many bans have since been lifted.
Other megabats implicated as disease reservoirs are primarily Pteropus species. Notably, flying foxes can transmit Australian bat lyssavirus, which, along with the rabies virus, causes rabies. Australian bat lyssavirus was first identified in 1996; it is very rarely transmitted to humans. Transmission occurs from the bite or scratch of an infected animal but can also occur from getting the infected animal's saliva in a mucous membrane or an open wound. Exposure to flying fox blood, urine, or feces cannot cause infections of Australian bat lyssavirus. Since 1994, there have been three records of people becoming infected with it in Queensland—each case was fatal.
Flying foxes are also reservoirs of such as Hendra virus and Nipah virus. Hendra virus was first identified in 1994; it rarely occurs in humans. From 1994 to 2013, there have been seven reported cases of Hendra virus affecting people, four of which were fatal. The hypothesized primary route of human infection is via contact with that have come into contact with flying fox Urination. There are no documented instances of direct transmission between flying foxes and humans. As of 2012, there is a vaccine available for horses to decrease the likelihood of infection and transmission.
Nipah virus was first identified in 1998 in Malaysia. Since 1998, there have been several Nipah outbreaks in Malaysia, Singapore, India, and Bangladesh, resulting in over 100 casualties. A 2018 outbreak in Kerala, resulted in 19 humans becoming infected—17 died. The overall fatality rate is 40–75%. Humans can contract Nipah virus from direct contact with flying foxes or their fluids, through exposure to an intermediate host such as , or from contact with an infected person. A 2014 study of the Indian flying fox and Nipah virus found that while Nipah virus outbreaks are more likely in areas preferred by flying foxes, "the presence of bats in and of itself is not considered a risk factor for Nipah virus infection." Rather, the consumption of date palm sap is a significant route of transmission. The practice of date palm sap collection involves placing collecting pots at date palm trees. Indian flying foxes have been observed licking the sap as it flows into the pots, as well as defecating and urinating in proximity to the pots. In this way, humans who drink palm wine can be exposed to henipaviruses. The use of bamboo skirts on collecting pots lowers the risk of contamination from bat urine.
Flying foxes can transmit several non-lethal diseases as well, such as Menangle virus and Nelson Bay virus. These viruses rarely affect humans, and few cases have been reported. Megabats are not suspected to be vectors of coronaviruses.
Indigenous societies in Oceania used parts of flying foxes for functional and ceremonial weapons. In the Solomon Islands, people created barbs out of their bones for use in spears. In New Caledonia, ceremonial axes made of jade were decorated with braids of flying fox fur. Flying fox wings were depicted on the war shields of the Asmat people of Indonesia; they believed that the wings offered protection to their warriors.
There are modern and historical references to flying fox byproducts used as currency. In New Caledonia, braided flying fox fur was once used as currency.
On the island of Makira, which is part of the Solomon Islands, indigenous peoples still hunt flying foxes for their teeth as well as for bushmeat.
The Canine tooth are strung together on necklaces that are used as currency. Teeth of the insular flying fox ( Pteropus tonganus) are particularly prized, as they are usually large enough to drill holes in. The Makira flying fox ( Pteropus cognatus) is also hunted, despite its smaller teeth. Deterring people from using flying fox teeth as currency may be detrimental to the species, with Lavery and Fasi noting, "Species that provide an important cultural resource can be highly treasured." Emphasizing sustainable hunting of flying foxes to preserve cultural currency may be more effective than encouraging the abandonment of cultural currency. Even if flying foxes were no longer hunted for their teeth, they would still be killed for bushmeat; therefore, retaining their cultural value may encourage sustainable hunting practices. Lavery stated, "It's a positive, not a negative, that their teeth are so culturally valuable. The practice of hunting bats shouldn't necessarily be stopped, it needs to be managed sustainably."
Megabats are also killed by humans, intentionally and unintentionally. Half of all megabat species are hunted for food, in comparison to only eight percent of insectivorous species,
Climate change causes flying fox mortality and is a source of concern for species persistence. Extreme heat waves in Australia have been responsible for the deaths of more than 30,000 flying foxes from 1994 to 2008. Females and young bats are most susceptible to extreme heat, which affects a population's ability to recover. Megabats are threatened by sea level rise associated with climate change, as several species are endemic to low-lying .
Seed dispersal
Megabats play an important role in seed dispersal. As a result of their long evolutionary history, some plants have evolved characteristics compatible with bat senses, including fruits that are strongly scented, brightly colored, and prominently exposed away from foliage. The bright colors and positioning of the fruit may reflect megabats' reliance on visual cues and inability to navigate through clutter. In a study that examined the fruits of more than forty fig species, only one fig species was consumed by both birds and megabats; most species are consumed by one or the other. Bird-consumed figs are frequently red or orange, while megabat-consumed figs are often yellow or green. Most seeds are excreted shortly after consumption due to a rapid gut transit time, but some seeds can remain in the gut for more than twelve hours. This heightens megabats' capacity to disperse seeds far from parent trees. As highly mobile frugivores, megabats have the capacity to restore forest between isolated forest fragments by dispersing tree seeds to deforested landscapes. This dispersal ability is limited to plants with small seeds that are less than in length, as seeds larger than this are not ingested.
Predators and parasites
Megabats, especially those living on islands, have few native predators. Non-native predators of flying foxes include domestic and . The mangrove monitor, which is a native predator for some megabat species but an introduced predator for others, opportunistically preys on megabats, as it is a capable tree climber. Another species, the brown tree snake, can seriously impact megabat populations; as a non-native predator in Guam, the snake consumes so many offspring that it reduced the recruitment of the population of the Mariana fruit bat ( Pteropus mariannus) to essentially zero. The island is now considered a sink for the Mariana fruit bat, as its population there relies on bats immigrating from the nearby island of Rota to bolster it rather than successful reproduction. Predators that are naturally sympatric with megabats include reptiles such as , snakes, and large lizards, as well as birds like , , and . The saltwater crocodile is a known predator of megabats, based on analysis of crocodile stomach contents in northern Australia. During extreme heat events, megabats like the little red flying fox ( Pteropus scapulatus) must cool off and rehydrate by drinking from waterways, making them susceptible to opportunistic depredation by freshwater crocodiles.
Range and habitat
Megabats are widely distributed in the tropics of the Old World, occurring throughout Africa, Asia, Australia, and throughout the islands of the Indian Ocean and Oceania. As of 2013, fourteen genera of megabat are present in Africa, representing twenty-eight species. Of those twenty-eight species, twenty-four are only found in tropical or subtropical climates. The remaining four species are mostly found in the tropics, but their ranges also encompass temperate climates. In respect to habitat types, eight are exclusively or mostly found in habitat; nine are found in both forests and ; nine are found exclusively or mostly in savannas; and two are found on islands. Only one African species, the long-haired rousette ( Rousettus lanosus), is found mostly in montane ecosystems, but an additional thirteen species' ranges extend into montane habitat.
Relationship to humans
Food
Megabats are killed and eaten as bushmeat throughout their range. Bats are consumed extensively throughout Asia, as well as in islands of the West Indian Ocean and the Pacific, where Pteropus species are heavily hunted. In continental Africa where no Pteropus species live, the straw-colored fruit bat, the region's largest megabat, is a preferred hunting target.
As disease reservoirs
Megabats are the reservoirs of several that can affect humans and cause disease. They can carry , including the Ebola virus (EBOV) and Marburgvirus. The presence of Marburgvirus, which causes Marburg virus disease, has been confirmed in one species, the Egyptian fruit bat. The disease is rare, but the fatality rate of an outbreak can reach up to 88%. The virus was first recognized after simultaneous outbreaks in the German cities of Marburg and Frankfurt as well as Belgrade, in 1967, where 31 people became ill and seven died. The outbreak was traced to laboratory work with from Uganda. The virus can pass from a bat host to a human (who has usually spent a prolonged period in a mine or cave where Egyptian fruit bats live); from there, it can spread person-to-person through contact with infected bodily fluids, including blood and semen. The United States Centers for Disease Control and Prevention lists a total of 601 confirmed cases of Marburg virus disease from 1967 to 2014, of which 373 people died (62% overall mortality).
In culture
Megabats, particularly flying foxes, are featured in indigenous cultures and traditions. Folk stories from Australia and Papua New Guinea feature them. (2025). 9781135917142, Routledge. ISBN 9781135917142 (2025). 9780971412712, Masalai Press. ISBN 9780971412712
They were also included in Indigenous Australian cave art, as evinced by several surviving examples. (2025). 9780643103764, Csiro Publishing. ISBN 9780643103764
(2025). 9780826414656, A&C Black. ISBN 9780826414656
Conservation
Status
As of 2014, the International Union for Conservation of Nature (IUCN) evaluated a quarter of all megabat species as threatened, which includes species listed as critically endangered, endangered, and vulnerable. Megabats are substantially threatened by humans, as they are hunted for food and medicinal uses.
Additionally, they are culled for actual or perceived damage to agriculture, especially to fruit production. (2025). 9783319252209, Springer. ISBN 9783319252209 As of 2019, the IUCN had evaluations for 187 megabat species. The status breakdown is as follows:
Factors causing decline
Anthropogenic sources
Megabats are threatened by habitat destruction by humans. Deforestation of their habitats has resulted in the loss of critical roosting habitat. Deforestation also results in the loss of food resource, as native fruit-bearing trees are felled. Habitat loss and resulting urbanization leads to construction of new roadways, making megabat colonies easier to access for overharvesting. Additionally, habitat loss via deforestation compounds natural threats, as fragmented forests are more susceptible to damage from typhoon-force winds. Cave-roosting megabats are threatened by human disturbance at their roost sites. Guano mining is a livelihood in some countries within their range, bringing people to caves. Caves are also disturbed by mineral mining and cave tourism.
(2025). 9783319252186, Springer. ISBN 9783319252186 while human persecution stemming from perceived damage to crops is also a large source of mortality. Some megabats have been documented to have a preference for native fruit trees over fruit crops, but deforestation can reduce their food supply, causing them to rely on fruit crops. They are shot, beaten to death, or poisoned to reduce their populations. Mortality also occurs via accidental entanglement in bird netting used to prevent the bats from eating fruit. Culling campaigns can dramatically reduce megabat populations. In Mauritius, over 40,000 Mauritian flying foxes were culled between 2014 and 2016, reducing the species' population by an estimated 45%. Megabats are also killed by electrocution. In one Australian orchard, it is estimated that over 21,000 bats were electrocuted to death in an eight-week period. Farmers construct electrified grids over their fruit trees to kill megabats before they can consume their crop. The grids are questionably effective at preventing crop loss, with one farmer who operated such a grid estimating they still lost of fruit to flying foxes in a year. (2025). 9780980327243, Royal Zoological Society of New South Wales. ISBN 9780980327243 Some electrocution deaths are also accidental, such as when bats fly into overhead power lines.
Natural sources
Because many species are endemic to a single island, they are vulnerable to random events such as typhoons. A 1979 typhoon halved the remaining population of the Rodrigues flying fox ( Pteropus rodricensis). Typhoons result in indirect mortality as well: because typhoons defoliate the trees, they make megabats more visible and thus more easily hunted by humans. Food resources for the bats become scarce after major storms, and megabats resort to riskier foraging strategies such as consuming fallen fruit off the ground. There, they are more vulnerable to depredation by domestic cats, dogs, and pigs. As many megabat species are located in the tectonically active Ring of Fire, they are also threatened by volcanic eruptions. Flying foxes, including the endangered Mariana fruit bat, have been nearly exterminated from the island of Anatahan following a series of eruptions beginning in 2003.
External links
|
|
