Overview

Brief Summary

Biology

Grey-headed flying foxes roost in large colonies, or 'camps', of up to tens of thousands of individuals among exposed branches during the day (7) (8). At dusk these bats emerge from the colony in search of food (9) (10), travelling up to 50 kilometres to their feeding areas (11) (12) (13). Their diet consists of fruit from a range of native and introduced species, as well as pollen and nectar, particularly of Eucalypt trees (11) (14) (15) (16) (17). Breeding is seasonal, and from January onwards males defend mating territories, which they demarcate by scent-marking, loud calls and aggression (18). Mating generally occurs between March and May (18) (19), with a single young born six months later between September and November (15). Females then carry their pup during foraging flights for the first three weeks, after which they are left behind in the camp (4) (15). Young are capable of flight and follow their mother to forage after three months, but are not weaned until five to six months (15) (19) (18).
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Wildscreen

Source: ARKive

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Description

The grey-headed flying fox is one of the largest bats in Australia, with the maximum recorded wingspan exceeding an impressive 1.5 metres (4). This bat has a dark grey body, a paler grey head, and a conspicuous collar of rich russet-coloured fur encircling the neck (4). As with all members of the Pteropodidae family, this bat lacks a tail and has claws on the first and second digits. Uniquely, however, the body fur of this species extends all the way down to the ankle, distinguishing it from other flying foxes (Pteropus species), which only bear fur down to their knees (4).
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Wildscreen

Source: ARKive

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Distribution

Range Description

This species is endemic to eastern Australia, where it ranges from south-eastern Queensland, through eastern New South Wales to Victoria. There has been a contraction of the northern extent of the range in recent years (by 500 km in past 100 years), and an increase in the numbers in the south, with increasing permanent colonies (L. Lumsden pers. comm.).
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© International Union for Conservation of Nature and Natural Resources

Source: IUCN

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Geographic Range

Pteropus poliocephalus is endemic to the eastern coast of Australia. These bats can be found from Bundaberg and Mayborough in Queensland to Melbourne in Victoria. The previous range has shifted southward by approximately 750 km, possibly due to a change in climate.

Biogeographic Regions: australian (Native )

  • Parry-Jones, K., M. Augee. 2001. Factors affecting the occupation of a colony site in Sydney, New South Wales by the Grey-headed Flying-fox Pteropus poliocephalus (Pteropodidae). Austral Ecology, 26/1: 47-55.
  • 2001. "Threatened Species Information: Grey-headed Flying-fox" (On-line pdf). NSW National Parks and Wildlife Service. Accessed November 13, 2004 at http://www.nationalparks.nsw.gov.au/PDFs/tsprofile_greyheaded_flyingfox.pdf.
  • Tidemann, C., J. Nelson. 2004. Long-distance movements of the grey-headed flying fox (Pteropus poliocephalus). Journal of Zoology, 263/2: 141-146.
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© The Regents of the University of Michigan and its licensors

Source: Animal Diversity Web

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Range

Endemic to the east coast of Australia, from Bundaberg in Queensland to Melbourne in Victoria (4) (5) (6).
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Wildscreen

Source: ARKive

Trusted

Article rating from 1 person

Average rating: 2.0 of 5

Physical Description

Morphology

Physical Description

Pteropus poliocephalus is the largest bat in Australia. As with all members of Pteropodidae, P. poliocephalus does not have a tail, and claws are present on the first and second digits. They do not echolocate, and therefore, the distinctive enlarged tragus or leaf-ornamentation found in most species of Microchiroptera is not present. Since they do not echolocate, they must rely on their large eyes for navigation and finding food.

As the species' common name implies, grey-headed flying-foxes have faces which are fox-like. The body is dark grey, with the fur on the head being of a lighter color grey. There is also a reddish-brown collar of fur that encircles the neck. Fur on the legs extends all the way to the ankle, which is one distinguishing characteristic from other members of the genus Pteropus. The patagium is black, and it is possible for the wingspan of some individuals to be up to one meter. The head and body length is between 230 and 289 mm, with an average of 253 mm. The forearm length is between 138 and 180 mm, with an average of 161 mm. Weight generally varies between 600 and 1000 g, with an average of 677 g. However, some individuals have been recorded as weighing more than 1 kg. These figures are somewhat different according to different sources, but they are generally within a few units of each other. These bats have a basal metabolic rate of approximately 3.162 cm^3 oxygen/h.

Range mass: 600 to 1000 g.

Average mass: 677 g.

Range length: 230 to 289 mm.

Average length: 253 mm.

Average wingspan: 1 m.

Average basal metabolic rate: 316.2 cm^3 oxygen/hour.

Other Physical Features: endothermic ; homoiothermic; bilateral symmetry

Sexual Dimorphism: male larger

Average basal metabolic rate: 1.768 W.

  • Taylor, J. 1984. The Oxford Guide To: Mammals of Australia. Melbourne: Oxford University Press.
  • Feldhamer, G., L. Drickamer, S. Vessey, J. Merritt. 2004. Mammalogy: Adaptation, Diversity, Ecology 2nd edition. New York: McGraw-Hill.
  • McNab, B., F. Bonaccorso. 1995. The energetics of pteropodid bats. Zoological Society of London Symposia, 67: 111-122.
  • Kunz, T., A. Stern. 1995. Maternal investment and post-natal growth in bats. Zoological Society of London Symposia, 67: 123-138.
  • Menkhorst, P. 2001. Field Guide to Mammals of Australia. Melbourne: Oxford University Press.
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© The Regents of the University of Michigan and its licensors

Source: Animal Diversity Web

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Ecology

Habitat

Habitat and Ecology

Habitat and Ecology
It is found in tropical moist forest, open forest, closed and open woodlands, Melaleuca swamps, Banksia woodlands, mangroves, and commercial fruit plantations. It also occurs in urban areas where suitable foraging and roosting habitat are available. The primary food source are the flowers of Eucalyptus, Banksia, Melaleuca species, plus rainforest fruits. It roosts in colonies in patches of trees and dense vegetation. Females generally give birth to a single young (Duncan et al. 1999; D. Lunney pers. comm.). Generation length is likely to be around six or seven years (A. Divljan pers. comm.).

Systems
  • Terrestrial
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© International Union for Conservation of Nature and Natural Resources

Source: IUCN

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Pteropus poliocephalus is found in a variety of habitats including rainforests, woodlands, and swamps located in Eastern Australia. They are typically found at elevations less than 200 m, but have been found at elevations as great as 700 m. These bats prefer to roost in the branches of large trees. They are usually not found more than 150 km inland and are even present on some secluded islands. Because of encroachment of human activity into their habitats, they are sometimes found in suburban areas, using the agricultural lands of their human neighbors as a food source. Pteropus poliocephalus is a semi-migratory species. The migrations of these animals have been attributed to different reasons. They often go where the food supply is abundant, although it has been hypothesized that they also undertake these long-distance flights to enhance their mating opportunities, or to gather more information about other parts of their range.

Range elevation: 700 (high) m.

Habitat Regions: temperate ; tropical ; terrestrial

Terrestrial Biomes: forest ; rainforest

Wetlands: swamp

Other Habitat Features: suburban ; agricultural ; riparian

  • Menkhorst, P. 1995. Grey-headed Flying-fox. Pp. 156-158 in P Menkhorst, ed. Mammals of Victoria. Melbourne: Oxford University Press.
  • Richards, G. 1984. Grey-headed Flying-fox. Pp. 274-276 in R Strahan, ed. The Australian Museum Complete Book of Australian Mammals: The National Photographic Index of Australian Wildlife. London: Angus and Robertson Publishers.
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© The Regents of the University of Michigan and its licensors

Source: Animal Diversity Web

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Found in a variety of habitats, including rainforests, woodlands, mangroves, swamps, but also in suburban and cultivated areas (4) (5). Typically found no more than 100 kilometres inland, and amongst trees at around 200 metres above sea level, although individuals have been recorded at elevations as great as 700 metres (4).
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Wildscreen

Source: ARKive

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Trophic Strategy

Food Habits

Foraging occurs at night, and it is not unusual for individuals to fly up to 50 km away from their campsites, although most tend to stay within 15 km. These bats tend to forage in forest canopies, open forests, rainforests, and even swamps; however, they sometimes visit cultivated gardens and fruit crops in search of food. When eating, the bats bite pieces off of their food, and then chew it vigorously, spitting out portions that are not swallowed. Different foods are eaten at different times of the year, depending on availability.

The diet of P. poliocephalus includes fruits, pollen, nectar, and bark. Their preferred food source is eucalyptus blossom, of which Eucalyptus gummifera, Eucalyptus muellerana, Eucalyptus globoidea and Eucalyptus botryoides are most often consumed. The main sources utilized for pollen consumption belong in the families Myrtaceae and Proteaceae, although pollens from other families are consumed when present. One of their favorite fruits is fig (Ficus); however, these bats have been known to consume stone fruits (e.g. peach, plum, nectarine). Occasionally they also consume the leaves of poplar (g. Populus) and grey mangrove (Avicennia marina). Other food items that have been found in fecal matter include fruits from Phoenix canariensis, Ligustrum and Solanum mauritianum, among many others.

Plant Foods: leaves; wood, bark, or stems; fruit; nectar; pollen; flowers

Primary Diet: herbivore (Frugivore )

Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© The Regents of the University of Michigan and its licensors

Source: Animal Diversity Web

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Associations

Ecosystem Roles

Many different fruits and pollens are consumed by P. poliocephalus, making this species highly important in seed dispersal and pollination of plants. Certain plants enjoy a wider range due to the long-distance seed dispersal that these bats offer. Without this, certain plant species could be negatively affected.

Ecosystem Impact: disperses seeds; pollinates

Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© The Regents of the University of Michigan and its licensors

Source: Animal Diversity Web

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Predation

Other Pteropus species are known to be preyed upon by snakes, such as brown tree snakes (Boiga irregularis). However, beyond reports of humans killing these animals, information pertaining to specific predators of P. poliocephalus was not found.

Known Predators:

  • humans

Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© The Regents of the University of Michigan and its licensors

Source: Animal Diversity Web

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Life History and Behavior

Behavior

Communication and Perception

What P. poliocephalus lacks in echolocation, it has made up for with a sophisticated array of vocalizations, which are comprised of a series of complicated squeaks and squeals. There are more than 20 different calls which these bats use in communicating with each other, and because they form large groups, roosting sites can be quite noisy.

Because they do not echolocate, they rely heavily on vision and olfaction in perceiving their environment. Their large eyes help them in navigating through their habitat. Males are known to use a strongly scented secretion in marking territory, and females are able to find their young by scent. Olfaction is also used in locating food items. Although not specifically reported, it is likely that there is important tactile communication between mothers and their young as well as between mates.

Communication Channels: visual ; tactile ; acoustic ; chemical

Other Communication Modes: scent marks

Perception Channels: visual ; acoustic

Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© The Regents of the University of Michigan and its licensors

Source: Animal Diversity Web

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Life Expectancy

Lifespan/Longevity

Grey-headed flying-foxes generally live for a long period of time, with the average reproductively active adult being between 6 and 10 years old. Two individuals are reported to have been 15 years old. However, the expected lifespan of wild individuals ranges from 21.6 to 59.2 months. Lifespan is affected mostly by food availability and negative human interactions, such as deforestation and culling. In captivity, where food availability is not an issue for survival, these bats have a much longer lifespan.

Range lifespan

Status: wild:
21.6 to 180 months.

Average lifespan

Status: wild:
40.4 months.

Typical lifespan

Status: wild:
21.6 to 59.2 months.

Average lifespan

Status: wild:
40.4 months.

Average lifespan

Status: captivity:
23.6 years.

Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© The Regents of the University of Michigan and its licensors

Source: Animal Diversity Web

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Lifespan, longevity, and ageing

Maximum longevity: 23.6 years (captivity) Observations: One specimen about 23.6 years old is still alive in captivity (Richard Weigl 2005).
Creative Commons Attribution 3.0 (CC BY 3.0)

© Joao Pedro de Magalhaes

Source: AnAge

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Reproduction

During the nursing period, males and females form monogamous mating-pairs. Males utilize strong-smelling secretions from their scapular glands (located on the shoulder) and loud calls in order to establish territories and ward off unwanted males.

Mating System: monogamous

Grey-headed flying foxes mate annually between April and May, with males reaching reproductive maturity at approximately 30 months of age. Mating has been observed throughout the year; however, males are only fertile during the mating period. Females that are close to giving birth segregate from the males. Mothers give birth to a single young between October and November, after a 6-month gestation period. Twins are extremely rare and do not usually survive in the wild. Weaning occurs between 5 and 6 months of age, and offspring are independent after about 6 months.

Breeding interval: Grey-headed flying-foxes breed once yearly.

Breeding season: Breeding occurs from April to May

Range number of offspring: 1 to 2 (rare).

Average number of offspring: 1.

Average gestation period: 6 months.

Range weaning age: 5 (low) months.

Average weaning age: 6 months.

Average time to independence: 6 months.

Average age at sexual or reproductive maturity (male): 30 months.

Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); fertilization ; viviparous

Average birth mass: 80 g.

Average number of offspring: 1.

Average age at sexual or reproductive maturity (male)

Sex: male:
540 days.

Average age at sexual or reproductive maturity (female)

Sex: female:
540 days.

When born, the young weigh between 46 and 92 grams and are somewhat altricial, as they cannot fly and have no fur on the underside. Female P. poliocephalus carry their young, which cling to the fur on the mother's belly, for the first 4 to 5 weeks after birth. Females carry their young even while foraging. For the next 12 weeks or so, the young are left at the nesting site at night while the mother forages. At about 3 months of age the young are independent enough to forage on their own; however, they are not completely weaned until about 6 months of age. This extended period of nursing is due to the fact that bats provide their young with milk until they have at least 90% of their adult wingspan and at least 70% of their adult body mass, because the young cannot achieve sustained flight until they have reached these dimensions. Females have been known to abandon their young in times of food shortages.

Although males do not directly care for the young, they do mark and defend territories for their families during the period of nursing. Thus, they play some role in protecting the young.

Parental Investment: altricial ; pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Male, Female); pre-weaning/fledging (Provisioning: Female, Protecting: Male, Female); pre-independence (Provisioning: Female, Protecting: Male, Female)

  • Webb, N., C. Tidemann. 1996. Mobility of Australian flying-foxes, Pteropus spp. (Megachiroptera): evidence from genetic variation. Proceedings: Biological Sciences, 263/1369: 497-502.
  • Kunz, T., A. Stern. 1995. Maternal investment and post-natal growth in bats. Zoological Society of London Symposia, 67: 123-138.
  • Nowak, R. 1999. Walker's Mammals of the World 6th ed. Baltimore: Johns Hopkins University Press.
  • 2001. "Threatened Species Information: Grey-headed Flying-fox" (On-line pdf). NSW National Parks and Wildlife Service. Accessed November 13, 2004 at http://www.nationalparks.nsw.gov.au/PDFs/tsprofile_greyheaded_flyingfox.pdf.
  • Menkhorst, P. 1995. Grey-headed Flying-fox. Pp. 156-158 in P Menkhorst, ed. Mammals of Victoria. Melbourne: Oxford University Press.
  • Richards, G. 1984. Grey-headed Flying-fox. Pp. 274-276 in R Strahan, ed. The Australian Museum Complete Book of Australian Mammals: The National Photographic Index of Australian Wildlife. London: Angus and Robertson Publishers.
  • Tidemann, C. 1995. Grey-headed Flying-Fox. Pp. 439-441 in R Strahan, ed. Mammals of Australia. Washington, D.C.: Smithsonian Institution Press.
  • Tidemann, C., J. Nelson. 2004. Long-distance movements of the grey-headed flying fox (Pteropus poliocephalus). Journal of Zoology, 263/2: 141-146.
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© The Regents of the University of Michigan and its licensors

Source: Animal Diversity Web

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Conservation

Conservation Status

IUCN Red List Assessment


Red List Category
VU
Vulnerable

Red List Criteria
A2ace

Version
3.1

Year Assessed
2008

Assessor/s
Lunney, D., Richards, G. & Dickman, C.

Reviewer/s
Lamoreux, J. (Global Mammal Assessment Team), Racey, P.A., Medellín, R. & Hutson, A.M. (Chiroptera Red List Authority)

Contributor/s

Justification
Listed as Vulnerable because of a continuing population decline, estimated to be more than 30% over the last three generations, inferred from direct observations, shrinkage in distribution and loss of overwintering foraging habitat, and probable competition and hybridisation with P. alecto.
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© International Union for Conservation of Nature and Natural Resources

Source: IUCN

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

At one time P. poliocephalus had a much larger range; however, that range is now shrinking due to habitat destruction. Many areas of their habitat are becoming increasingly urbanized, such as in S.E. Queensland and northern New South Wales (NSW). Also, conservation reserves are limited, and in NSW < 15% of suitable habitat is within these reserves.

The main threat to P. poliocephalus is the destruction of habitat through deforestation. Females are particularly subject to spontaneous abortions due to loss of habitat and food sources, or when they are disturbed at the nesting site during the last few weeks of pregnancy. There are no regulations pertaining to the shooting of these animals, and farmers whose crops are perceived as being threatened often kill them. These bats also suffer from the tendency to fly into power lines, thus dying from electrocution. Black flying-foxes (Pteropus alecto) also pose a threat because they are competitors over food and habitat, and P. poliocephalus has been known to mate and thus hybridize with them.

Currently this species is listed as vulnerable under the NSW Threatened Species Conservation Act 1995, schedule 2, and under the Environment Protection and Biodiversity Conservation Act 1999. It was at one point estimated that the population numbered somewhere in the millions. Recently, however, figures indicate that the population has had an approximately 30% decline over the last 10 years. However, not all organizations view this species as being threatened. It is listed on CITES as being of least concern, and not even present in a number of other threatened and/or endangered databases.

US Federal List: no special status

CITES: no special status

IUCN Red List of Threatened Species: vulnerable

Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© The Regents of the University of Michigan and its licensors

Source: Animal Diversity Web

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Status

Classified as Vulnerable (VU) on the IUCN Red List (1), and listed on Appendix II of CITES (3). Listed as Vulnerable on the New South Wales Threatened Species Conservation Act 1995 and the Commonwealth Environment Protection and Biodiversity Conservation Act 1999 in Australia (2).
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Wildscreen

Source: ARKive

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Population

Population
It is common in suitable habitat, but its habitat is limited (Tidemann et al. 2008). The population is declining throughout the range except in Victoria where the species is increasing in numbers (L. Lumsden pers. comm.). Surveys across the range showed declines of over 30% since 1990, and these declines were predicted continue in the future due to habitat loss (Eby and Lunney 2006).

Population Trend
Decreasing
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© International Union for Conservation of Nature and Natural Resources

Source: IUCN

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Threats

Major Threats
This species is threatened by loss of foraging and roosting habitat, largely through clearance of native vegetation for agriculture and forestry operations plus urban development (Duncan et al. 1999). The species requires multiple, dispersed populations of food trees (Duncan et al. 1999). The winter and early spring range of this species is limited to a narrow-coastal strip in Queensland and New South Wales that is targeted for residential development, and this is the primary threat (Duncan et al. 1999; Eby and Lunney 2002).

It is a pest of commercial fruit trees in parts of its range and animals are directly killed under license in orchards in New South Wales and Queensland; there is also likely to be unlicensed killing (Duncan et al. 1999; Tidemann et al. 2008; D. Lunney pers. comm.). The species is believed to be threatened by competition and hybridisation with Pteropus alecto, which has expanded southward at the same time as the range of P. poliocephalus has been reduced in the north (Duncan et al. 1999; G. Richards pers. comm.). The rapid rate of expansion range extension by P. alecto (by 500 km from 1990 to 2006) is of particular concern (P. Eby pers. comm.). It is additionally threatened by pollutants in urban areas and potentially by a number of viral pathogens (Duncan et al. 1999).
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© International Union for Conservation of Nature and Natural Resources

Source: IUCN

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Although once thought to number in their millions, in 2002 there were estimated to be around 400,000 grey-headed flying foxes remaining (20). The most significant threat facing the bat is the destruction of foraging and roosting habitat due to expanding urbanisation and agriculture (7) (15). Climate change may also pose a threat to the grey-headed flying-fox as climate models are predicting significant increases in the occurrence of temperature extremes and recent research has shown that since 1994, more than 24,500 grey-headed flying foxes have died in their roosts when temperatures exceeded 42 degrees Celsius (21). Another serious threat is direct killing of animals in orchards and destruction of roosts. Many farmers perceive the bats to be pests due to the destruction they cause to crops and often kill them (22). Further more, negative public perception and consequent persecution of the species has intensified in the last decade with the discovery that it carries three new diseases that are potentially fatal to humans, Hendravirus, Menanglevirus and Australian Bat Lyssavirus (23) (24) (25). The exact numbers of bats killed is unknown, but estimates have been made as high as 100,000 annually, with the death of pregnant or lactating females obviously having an additional knock-on impact on the survival of their young (26). There is also a tendency for these bats to fly into power lines and die from electrocution. Black flying foxes (Pteropus alecto) pose a further threat through competition for food and habitat, and hybridisation between the grey-headed flying fox and the black flying fox has been observed (7) (27) (28).
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Wildscreen

Source: ARKive

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Management

Conservation Actions

Conservation Actions
This species is listed on Appendix II of CITES. It is present within a number of protected areas, however, none of these contain all of the conditions needed to maintain viable populations (Duncan et al. 1999). Further studies are needed into the population status and trends of this species, demographics, and population structure, in order to understand movement patterns (notably for recolonisation), define habitat requirements relative to protected areas (especially in winter/spring habitat), and to develop cost-effective methods of protecting fruit crops from this species (Duncan et al. 1999). The species breeds well in captivity (Strahan 1995). Education is needed to reduce negative public attitudes to this species. There is also a need for an assessment and reduction of any threats from power lines, barbed wire fences, and netting. There is a draft Recovery Plan for this species (Eby and Lunney 2006).
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© International Union for Conservation of Nature and Natural Resources

Source: IUCN

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Conservation

In response to these growing threats, roost sites have been legally protected since 1986 in New South Wales and 1994 in Queensland (22). The grey-headed flying fox was also listed as vulnerable under the Environment Protection and Biodiversity Conservation Act in 1999, and the New South Wales Threatened Species Conservation Act Schedule 2 in 1995, which required that a Recovery Plan be prepared by 2006 (27) (29) (30). Conservation reserves are limited, and future efforts to protect more key foraging areas would be extremely beneficial, by helping to ensure that food supplies are available throughout the year (2). Research into alternative, non-lethal crop protection mechanisms, and encouragement of horticulturists to use them, is also crucial in the fight to protect this species (2). As important pollinators and seed dispersal agents, these bats are integral in maintaining healthy forest ecosystems (16). Thus, unless swift action is taken to halt further population reductions, the decline of the grey-headed flying fox is likely to have a serious negative, long-term impact on the regeneration of Australia's forests, and the host of unique fauna they harbour.
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Wildscreen

Source: ARKive

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Relevance to Humans and Ecosystems

Benefits

Economic Importance for Humans: Negative

Pteropus poliocephalus is often believed to be detrimental to cultivated fruit crops, and thus farmers sometimes view the species as a pest. However, these bats only resort to eating fruit crops when other food sources become sparse. They are also thought to be a potential carrier of viral pathogens.

Negative Impacts: crop pest; causes or carries domestic animal disease

Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© The Regents of the University of Michigan and its licensors

Source: Animal Diversity Web

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Economic Importance for Humans: Positive

Since P. poliocephalus eats many different fruits and nectars, it is an important pollinator, especially for certain Eucalyptus species. They are also important in transporting and distributing the seeds long distances. Therefore, there is a great possibility that a population reduction of this bat would have some negative long-term impacts on the regeneration of Australia’s forests. As a result of habitat destruction decreasing their range, they have thus had a reduction in migratory patterns, which, too, may lead to negative consequences for the ecosystem and for humans.

Positive Impacts: pollinates crops

Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© The Regents of the University of Michigan and its licensors

Source: Animal Diversity Web

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Wikipedia

Grey-headed flying fox

The grey-headed flying fox (Pteropus poliocephalus) is a megabat native to Australia.[2] The species shares the continent with three other members of the genus Pteropus: the little red flying fox, the spectacled flying fox, P. conspicillatus, and the black flying fox, P. alecto.

The grey-headed flying fox is endemic to the south-eastern forested areas of Australia, principally east of the Great Dividing Range. Its range extends approximately from Bundaberg to Geelong in Victoria, with outlying colonies in Ingham and Finch Hatton in the north, and in Adelaide in the south. In the southern parts of its range it occupies more extreme latitudes than any other Pteropus species.

Physical characteristics[edit]

Grey-headed flying-fox shows wingspan

The grey-headed flying fox is the largest bat in Australia. This flying fox has a dark-grey body with a light-grey head and a reddish-brown neck collar of fur. It is unique among bats of the genus Pteropus in that fur on the legs extends all the way to the ankle. Adults have an average wingspan up to 1 m (3.3 ft) and can weigh up to 1 kg (2.2 lb). The head and body length is between 230 and 289 mm (9.1 and 11.4 in), with an average of 253 mm (10.0 in). The forearm length is between 138 and 180 mm (5.4 and 7.1 in), with an average of 161 mm. Weight generally varies between 600 and 1,000 g (1.3 and 2.2 lb), with an average of 677 g (1.493 lb). It is tailless, with claws on its first and second digits. Since it does not echolocate, it lacks tragus or leaf ornamentation found in most species of Microchiroptera. It relies on sight to locate its food (nectar, pollen and native fruits) and thus has relatively large eyes for a bat.

The grey-headed flying fox is long-lived for a mammal of its size. Individuals reportedly survived in captivity for up to 23 years, and a maximum age of up to 15 years seems possible in the wild.[citation needed]

Ecology[edit]

Habitat and movements[edit]

Grey-headed flying foxes live a variety of habitats, including rainforests, woodlands, and swamps.[3] During the day, individuals reside in large roosts (colonies or 'camps') consisting of hundreds to tens of thousands of individuals. Colonies are formed in seemingly arbitrary locations. Roost vegetation includes rainforest patches, stands of melaleuca, mangroves, and riparian vegetation, but roosts also occupy highly modified vegetation in urban areas. A prominent example existed at the Royal Botanic Gardens in Sydney. However, the Garden instituted a successful policy to remove them from the garden grounds. The camp is now dispersed across Queensland.[4][5]

Movements of grey-headed flying foxes are influenced by the availability of food. Their population is very fluid, as they move in response to the irregular blossoming of certain plant species. The grey-headed flying fox is a partial migrant that uses winds to facilitate long-distance movement.[6] It does not migrate in a specific direction, but rather in the direction that will be the most beneficial at the time.[6]

Diet and foraging[edit]

Grey-headed flying fox colony

Around dusk, grey-headed flying foxes leave the roost and travel up to 50 km a night to feed on pollen, nectar and fruit.[6] The species consumes fruit flowers and pollens of around 187 plant species.[7] Theses include Eucalyptus, particularly Eucalyptus gummifera, Eucalyptus muellerana, Eucalyptus globoidea and Eucalyptus botryoides,[3][8] and fruits from a wide range of rainforest trees, including members of the Ficus genus.[3][8] These bats are considered sequential specialists, since they feed on a variety of foods.[8] Grey-headed flying foxes, along with the three other Australian flying fox species, fulfill a very important ecological role by dispersing the pollen and seeds of a wide range of native Australian plants. The grey-headed flying fox is the only mammalian nectarivore and frugivore to occupy substantial areas of subtropical rainforests, so is of key importance to those forests.

Most vegetation communities on which this species forages produce nectar and pollen seasonally and are abundant unpredictably, so the flying fox's migration traits cope with this. The time when flying foxes leave their roosts to feed depends on foraging light and predation risk.[9] Flying foxes have more time and light when foraging if they leave their roosts early in the day.[9] The entire colony may leave later if a predatory bird is present, while lactating females leave earlier.[9] With males, the bachelors leave earlier than harem-holding males, which guard their wait until all their females have left.[9] The flying foxes that leave the roost earlier are more vulnerable to predation, and some other flying foxes will wait for others to leave, a phenomenon labelled the "after you" effect.[9]

Social organisation[edit]

Groupings and territories[edit]

Grey-headed flying foxes form two different roosting camps, summer camps and winter camps.[10] Summer camps are used from September to April or June. In these camps, they establish territories, mate, and reproduce.[10] Winter camps are used from April to September. The sexes are separated in winter camps and most behaviour is characterised by mutual grooming.[10] Summer camps are considered "main camps", while winter camps are referred to as "transit camps".[10]

In their summer camps, starting in January, male grey-headed flying foxes set up mating territories. Mating territories are generally 3.5 body lengths along branches.[11] These flying foxes' neck glands enlarge in males in the mating season, and are used to mark the territories.[11] The males fight to maintain their territories, and this is associated with a steep drop in the males' body condition during this time.[12][13] Around the beginning of the mating season, adult females move from the periphery towards the central male territories where they become part of short-term ‘harems’ that consist of a male and an unstable group of up to five females.[11] Centrally located males are polygamous, while males on the periphery are monogamous or single.[10][11] The mating system of the grey-headed flying fox is best described as a lek because males do not provide any essential resources to females and are chosen on the basis of their physical location within the roost, which correlates with male quality.[11]

It was not until the 1980s that Grey-headed flying foxes first arrived in Melbourne.[14] Their hitherto absence and recent arrival has been postulated as possibly due to increase urbanisation leading to warmer temperatures.[14]

Mating[edit]

Matings are generally observed between March and May, but the most likely time of conception is April.[15] Most mating takes place in the territories and during the day. Females have control over the copulation process, and males may have to keep mating with the same females.[16] Females usually give birth to one young each year.[17] Gestation lasts around 27 weeks,[18] and pregnant females give birth between late September and November. Late births into January are sometimes observed. The altricial newborns rely on their mothers for warmth.[19] For their first three weeks, young cling to their mothers when they go foraging. After this, the young remain in the roosts. By January, young are capable of sustained flight, and by February, March or April are fully weaned.

Predation[edit]

Flying foxes are preyed on by eagles, goannas, and snakes,[10] as well as crocodiles.

Conservation[edit]

A grey-headed flying fox electrocuted between electricity transmission lines in suburban Sydney

The grey-headed flying fox is now a prominent federal conservation problem in Australia. Early in the last century, the species was considered abundant, with numbers estimated in the many millions. In recent years, though, direct evidence has been accumulating that the species is in serious decline. Current estimates for the species are about 300,000, and the national population may have declined by over 30% between 1989 and 1999 alone.[20]

Threats[edit]

Grey-headed flying foxes are exposed to several threats, including loss of foraging and roosting habitat,[21] competition with the black flying fox, and mass die-offs caused by extreme temperature events.[11] When present in urban environments, grey-headed flying foxes are sometimes perceived as a nuisance. Cultivated orchard fruits are also taken, but apparently only at times when other food items are scarce. Because their roosting and foraging habits bring the species into conflict with humans, they suffer from direct killing of animals in orchards and harassment and destruction of roosts. Negative public perception of the species has intensified with the discovery of three recently emerged zoonotic viruses that are potentially fatal to humans: Hendra virus, Australian bat lyssavirus and Menangle virus.[22] However, only Australian bat lyssavirus is known from two isolated cases to be directly transmissible from bats to humans.

A male grey-headed flying fox, suffering from heat stress during a recent heatwave in New South Wales

Recent research has shown, since 1994, more than 24,500 grey-headed flying foxes have died from extreme heat events alone.[23] These Australian flying fox die-offs are of increasing concern for the survival of this species now that climate models predict significant increases in the intensity, duration, and frequency of such temperature extremes.

To answer some of the growing threats, roost sites have been legally protected since 1986 in New South Wales and since 1994 in Queensland. In 1999, the species was classified as "Vulnerable to extinction" in The Action Plan for Australian Bats,[24] and has since been protected across its range under Australian federal law. As of 2008 the species is listed as "Vulnerable" on the IUCN Red List of Threatened Species.

Wildlife rescue[edit]

Crib full of abandoned babies rescued by Wildcare Australia in care at The Bat Hospital

Bat caregivers are not only specially trained in techniques to rescue and rehabilitate bats, but they are also vaccinated against rabies. Although the chance of contracting the rabies-like Australian bat lyssavirus is extremely small, bat caregivers are inoculated for their own protection.

Flying foxes often come to the attention of Australian wildlife care and rescue organisations, such as Wildcare Australia, ONARR, Wildlife Carers Darling Downs, Bat Care, Bat Rescue, Tweed Valley Wildlife Carers, WIRES, and Wildlife Victoria when reported as injured, sick, orphaned, or abandoned. A very high proportion of adult flying fox injuries are caused by entanglement in barbed wire fences or loose, improperly erected fruit tree netting, both of which can result in very serious injuries and a slow, agonising death for the animal if not rescued quickly.

Baby flying foxes usually come into care after having been separated from their mothers. Babies are often orphaned during four to six weeks of age, when they inadvertently fall off their mothers during flight. When they are older, orphans usually come into care because of maternal death from power line electrocution or barbed wire entanglement. A rare, but apparent natural, occurrence of mass abandonment can lead to the rescue of hundreds of babies at one time. The latter most recently occurred in November 2008 at the Canungra bat camp in South East Queensland, when Wildcare Australia, working closely with the EPA and regional bat care groups, rescued and rehabilitated over 300 baby grey-headed flying foxes. Most babies are in a dehydrated and distressed state by the time they are rescued, and some are infested with maggots if found sick or injured. A young flying fox must be fed every four hours, and then as it develops it is introduced to blossoms and fruit. When the young flying fox is fully weaned around 10 to 12 weeks of age, it goes into a crèche for rehabilitation and eventual release.

Gallery[edit]

References[edit]

  1. ^ Lunney, D., Richards, G. & Dickman, C. (2008). "Pteropus poliocephalus". IUCN Red List of Threatened Species. Version 2011.2. International Union for Conservation of Nature. Retrieved 31 December 2011. 
  2. ^ Simmons, N. B. (2005). "Order Chiroptera". In Wilson, D. E.; Reeder, D. M. Mammal Species of the World (3rd ed.). Johns Hopkins University Press. p. 342. ISBN 978-0-8018-8221-0. OCLC 62265494. 
  3. ^ a b c Menkhorst, P. 1995. "Grey-headed Flying-fox". pp. 156–158 in P. Menkhorst, ed. Mammals of Victoria. Melbourne: Oxford University Press.
  4. ^ "Sydney's flying foxes now Bundy's problem". North Queensland Register. 2 Aug 2012. Retrieved 2014-02-22. 
  5. ^ "Say goodbye to Sydney's colony of bats". Australian Geographic. 2011-02-17. Retrieved 2014-02-22. 
  6. ^ a b c Tidemann, C., J. Nelson. 2004. "Long-distance movements of the grey-headed flying-fox (Pteropus poliocephalus)". Journal of Zoology, 263/2: 141–146.
  7. ^ Williams, N. S. G.; McDonnell, M.J.; Phelan, G.K.; Keim, L.D.; der Ree, R. (2006). "Range expansion due to urbanisation, Increased food resources attract Grey-headed Flying-foxes (Pteropus poliocephalus) to Melbourne". Austral Ecology 31: 190–198. doi:10.1111/j.1442-9993.2006.01590.x. 
  8. ^ a b c Parry-Jones, K., M. Augee. 2001. "Factors affecting the occupation of a colony site in Sydney, New South Wales by the Grey-headed Flying-fox Pteropus poliocephalus (Pteropodidae)". Austral Ecology, 26/1: 47–55.
  9. ^ a b c d e Welbergen, J. A. (2006). "Timing of the evening emergence from day roosts of the grey-headed flying fox, Pteropus poliocephalus: the effects of predation risk, foraging needs, and social context". Behavioral Ecology and Sociobiology 60 (3): 311–322. doi:10.1007/s00265-006-0167-3.  edit
  10. ^ a b c d e f Nelson, J. E. (1965). "Behaviour of Australian Pteropodidae (Megachiroptera)". Animal Behaviour 13: 544–557. doi:10.1016/0003-3472(65)90118-1. PMID 5882814. 
  11. ^ a b c d e f Welbergen, J.A. (2005) "The social organisation of the grey-headed flying-fox". Ph.D thesis, University of Cambridge, Cambridge.
  12. ^ Welbergen, J. A. (2011). "Fit females and fat polygynous males: Seasonal body mass changes in the grey-headed flying fox". Oecologia 165 (3): 629–637. doi:10.1007/s00442-010-1856-1. PMID 21153744.  edit
  13. ^ Welbergen, J.A. (2010). "Growth, bimaturation, and sexual size dimorphism in wild gray-headed flying foxes (Pteropus poliocephalus)". Journal of Mammalogy 91 (1): 38–47. doi:10.1644/09-MAMM-A-157R.1. 
  14. ^ a b David Lindenmayer; Mark A. Burgman (2005). "Practical Conservation Biology". Google Books. CSIRO Publishing. p. 247. Retrieved 29 January 2014. 
  15. ^ Martin, L., Kennedy, J.H., Little, L., & Luckhoff, H.C. (1993) "The reproductive biology of Australian flying-foxes (genus Pteropus)". In Ecology, evolution and behaviour of bats (ed S.M. Swift), pp. 167–186. Oxford, London.
  16. ^ Welbergen, J.A. (2002). "Second year report: The social organisation of the Grey-Headed Flying-Fox, Pteropus poliocephalus: causes, consequences, and conservation." The Department of Zoology, The University of Cambridge, Cambridge.
  17. ^ Hall, L. S. & Richards, G. C. (2000). Flying-foxes: fruit and blossom bats of Australia. Sydney: University of New South Wales Press. ISBN 0-86840-561-2. 
  18. ^ O'Brien, G.M. (1993). "Seasonal reproduction in flying-foxes, reviewed in the context of other tropical mammals". Reproduction Fertility and Development 5: 499–521. doi:10.1071/rd9930499. 
  19. ^ Bartholomew, G.A.; Leitner, P.; Nelson, J.E. (1964). "Body temperature oxygen consumption and heart rate in three species of Australian flying-foxes". Physiological Zoology 37: 179–198. 
  20. ^ Richards, G. (2000). In Proceedings of a workshop to assess the status of the Grey-headed Flying-Fox (eds G. Richards & L. Hall). Australasian Bat Society, Canberra.
  21. ^ Eby, P. (1995). "The biology and management of flying-foxes" in NSW. Rep. No. 18. N.S.W. National Parks and Wildlife Service, Hurstville.
  22. ^ Allworth, A.; Murray, K.; Morgan, J.A. (1996). "Human case of encephalitis due to a lyssavirus recently identified in fruit bats". Communicable Diseases Intelligence 20: 504. 
  23. ^ Welbergen, J.; Klose, S.; Markus, N.; Eby, P. (2008). "Climate change and the effects of temperature extremes on Australian flying-foxes". Proceedings. Biological sciences / the Royal Society 275 (1633): 419–425. doi:10.1098/rspb.2007.1385. PMC 2596826. PMID 18048286.  edit
  24. ^ "The Action Plan for Australian Bats - Recovery outlines: Grey-headed Flying-fox". Environment.gov.au. Retrieved 2014-02-22. 

Further reading[edit]

Creative Commons Attribution Share Alike 3.0 (CC BY-SA 3.0)

Source: Wikipedia

Unreviewed

Article rating from 0 people

Default rating: 2.5 of 5

Disclaimer

EOL content is automatically assembled from many different content providers. As a result, from time to time you may find pages on EOL that are confusing.

To request an improvement, please leave a comment on the page. Thank you!