Jump to content

Grey-headed flying fox: Difference between revisions

From Wikipedia, the free encyclopedia
Content deleted Content added
Endangered
Ecology: Add spread
Tags: Mobile edit Mobile app edit Android app edit
 
(48 intermediate revisions by 33 users not shown)
Line 1: Line 1:
{{Short description|Species of bat}}
{{speciesbox
{{Use dmy dates|date=June 2020}}
{{Speciesbox
| name = Grey-headed flying fox
| name = Grey-headed flying fox
| image = Grey headed flying fox - Mating behaviour - AndrewMercer - DSC11277 - crop.jpg
| image = P._poliocephalus.jpg
| status = EN
| status = VU
| status_system = IUCN3.1
| status_system = IUCN3.1
| status_ref = <ref name=iucn>{{cite iucn |author=Eby, P. |author2=Roberts, B. |author3=Pennay, M. |author4=Welbergen, J.A. |year=2021 |title=''Pteropus poliocephalus'' |volume=2021 |page=e.T18751A22085511 |doi=10.2305/IUCN.UK.2021-3.RLTS.T18751A22085511.en |access-date=12 December 2021}}</ref>
| status_ref = <ref name="IUCN" />
| genus = Pteropus
| genus = Pteropus
| species = poliocephalus
| species = poliocephalus
| authority = [[Coenraad Jacob Temminck|Temminck]], 1825.<ref name="Temminck1824" />
| authority = [[Coenraad Jacob Temminck|Temminck]], 1825.<ref name="Temminck1824" />
| range_map = Grey-headed Flying-fox Distribution Map Orange.gif
| range_map = Grey-headed Flying-fox Distribution Map Orange.gif
| range_map_caption = Native distribution of ''P. poliocephalus''
| range_map_caption = Native distribution of ''Pteropus poliocephalus''
}}
}}


The '''grey-headed flying fox''' (''Pteropus poliocephalus'') is a [[megabat]] native to [[Australia]].<ref name = MSW3>{{MSW3 Chiroptera | id = 13800351 | page = 342}}</ref> The species shares mainland Australia with three other members of the [[genus]] ''[[Pteropus]]'': the little red ''[[Pteropus scapulatus|P. scapulatus]]'', spectacled ''[[Pteropus conspicillatus|P. conspicillatus]]'', and the black ''[[Pteropus alecto|P. alecto]]''.
The '''grey-headed flying fox''' ('''''Pteropus poliocephalus''''') is a [[megabat]] native to [[Australia]].<ref name = MSW3>{{MSW3 Chiroptera | id = 13800351 | page = 342}}</ref> The species shares mainland Australia with three other members of the [[genus]] ''[[Pteropus]]'': the little red ''[[Pteropus scapulatus|P. scapulatus]]'', spectacled ''[[Pteropus conspicillatus|P. conspicillatus]]'', and the black ''[[Pteropus alecto|P. alecto]]''. The grey-headed flying fox is the largest bat in Australia.


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, Queensland|Bundaberg]] in Queensland to [[Geelong, Victoria|Geelong]] in [[Victoria (Australia)|Victoria]], with outlying colonies in [[Ingham, Queensland|Ingham]] and [[Finch Hatton, Queensland|Finch Hatton]] in the north, and in [[Adelaide, South Australia|Adelaide]] in the south. In the southern parts of its range it occupies more extreme latitudes than any other ''Pteropus'' species.
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, Queensland|Bundaberg]] in Queensland to [[Geelong, Victoria|Geelong]] in [[Victoria (Australia)|Victoria]], with outlying colonies in [[Ingham, Queensland|Ingham]] and [[Finch Hatton, Queensland|Finch Hatton]] in the north, and in [[Adelaide, South Australia|Adelaide]] in the south. In the southern parts of its range it occupies more extreme latitudes than any other ''Pteropus'' species.

As of 2021 the species is listed as "[[vulnerable species|Vulnerable]]" on the [[IUCN Red List|IUCN Red List of Threatened Species]].<ref name=iucn />


== Taxonomy ==
== Taxonomy ==
Line 22: Line 26:


==Description==
==Description==
[[File:GreyHeadedFlyingFoxWingspan.jpg|thumb|Grey-headed flying-fox shows wingspan]]
[[File:Grey headed flying fox - skimming water - AndrewMercer - DSC00530.jpg|thumb|Wingspan is visible as this flying fox skims water to drink.]]
The grey-headed flying fox is the largest bat in Australia, with the adult wingspan reaching up to {{cvt|1|m}} in length and weighing up to {{cvt|1|kg}}.<ref name=nsw>{{cite web | title=Grey-headed Flying-fox - profile | website=NSW Environment, Energy and Science | date=2 June 2014 | url=https://www.environment.nsw.gov.au/threatenedspeciesapp/profile.aspx?id=10697 | access-date=30 December 2021}}</ref> Weight generally varies between {{cvt|600|and|1000|g}}, with an average of {{cvt|700|g}}. The combined length of the head and body is from 230 to 290&nbsp;mm. The forearm length is a range from 138 to 180&nbsp;mm. The length of the ear from the tip to base is 30 to 37&nbsp;mm.<ref name="Menkhorst2011" />
The grey-headed flying fox is the largest bat in Australia.

The overall colour of the [[pelage]] is a dark-grey body with a light-grey head, separated by a reddish-brown collar.
The overall colour of the [[pelage]] is a dark-grey body with a light-grey head, separated by a reddish-brown collar.
The fur on the body is long and streaked with grey, the broad and well defined collar completely encircles the neck with hair that is golden orange in tone.
The fur on the body is long and streaked with grey, the broad and well defined collar completely encircles the neck with hair that is golden orange in tone. A unique characteristic among bats of the genus ''Pteropus'' is fur on the legs that extends all the way to the ankle.<ref name="Menkhorst2011" />
A unique characteristic among bats of the genus ''Pteropus'' is fur on the legs that extends all the way to the ankle.
Adults may have a wingspan reaching one metre in length and be up to one kilogram in weight.
Weight generally varies between 600 and 1000 grams, with an average of 700&nbsp;g.
<ref name="Menkhorst2011" />


The combined length of the head and body is from 230 to 290&nbsp;mm.
The forearm length is a range from 138 to 180&nbsp;mm. The length of the ear from the tip to base is 30 to 37&nbsp;mm. <ref name="Menkhorst2011" />
Like many [[megachiroptera]]ns, the species lacks a tail. All of these bats possess claws on its first and second digits.
Like many [[megachiroptera]]ns, the species lacks a tail. All of these bats possess claws on its first and second digits.
The head is simple in form, with the characteristic 'dog-like' appearance of the genus.
The head is simple in form, with the characteristic 'dog-like' appearance of the genus.
Line 41: Line 40:


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|date=December 2010}}
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|date=December 2010}}

Grey-headed flying foxes have been found to experience [[torpor]].<ref>{{Cite journal |last=Turbill |first=Christopher |last2=Walker |first2=Melissa |last3=Boardman |first3=Wayne |last4=Martin |first4=John M. |last5=McKeown |first5=Adam |last6=Meade |first6=Jessica |last7=Welbergen |first7=Justin A. |date=2024-07-10 |title=Torpor use in the wild by one of the world’s largest bats |url=https://royalsocietypublishing.org/doi/10.1098/rspb.2024.1137 |journal=Proceedings of the Royal Society B: Biological Sciences |language=en |volume=291 |issue=2026 |doi=10.1098/rspb.2024.1137 |issn=1471-2954}}</ref>


==Ecology==
==Ecology==
=== Distribution ===
=== Distribution ===
The distribution range is at the eastern regions of the Australian continent, mostly within 200 kilometres of the coast, from [[Gladstone, Queensland|Gladstone]] in Queensland through to the southern [[Gippsland]] region and populations around the city of [[Melbourne]]. The breeding range has been recorded as progressing southward, the temperate climate of Melbourne and [[Geelong]] and no further north than [[Maryborough, Queensland]].<ref name="Menkhorst2011" />
The distribution range is at the eastern regions of the Australian continent, mostly within 200 kilometres of the coast, from [[Gladstone, Queensland|Gladstone]] in Queensland through to the southern [[Gippsland]] region and populations around the city of [[Melbourne]]. The breeding range has been recorded as progressing southward, the temperate climate of Melbourne and [[Geelong]] and no further north than [[Maryborough, Queensland]].<ref name="Menkhorst2011" />


[[Urbanisation]] may displace the species, or provide habitat that accommodates their feeding or roosting preferences. The city of Brisbane has many roosts occupied by the species; a famous colony at the [[Indooroopilly Island]] is noted for the evening departure of the bats across the local river. Within the central business district of Sydney, they can be seen travelling along city streets to feed at [[Moreton Bay fig]] trees at [[Hyde Park, Sydney|Hyde Park]].{{sfn|Richards|2012|pp=28–30}} The species was recorded as an occasional visitor to the national capital Canberra, although the flowering eucalypts at [[Commonwealth Park]] have seen more permanent camps established close to the city.{{sfn|Richards|2012|p=33}}
[[Urbanisation]] may displace the species, or provide habitat that accommodates their feeding or roosting preferences. The city of Brisbane has many roosts occupied by the species; a famous colony at the [[Indooroopilly Island]] is noted for the evening departure of the bats across the local river. Within the central business district of Sydney, they can be seen travelling along city streets to feed at [[Moreton Bay fig]] trees at [[Hyde Park, Sydney|Hyde Park]].{{sfn|Richards|2012|pp=28–30}} The species was recorded as an occasional visitor to the national capital Canberra, although the flowering eucalypts at [[Commonwealth Park]] have seen more permanent camps established close to the city.{{sfn|Richards|2012|p=33}}
Line 52: Line 53:
===Habitat and movements===
===Habitat and movements===
[[File:Pteropus poliocephalus colony.JPG|thumb|250px|right|Grey-headed flying fox colony]]
[[File:Pteropus poliocephalus colony.JPG|thumb|250px|right|Grey-headed flying fox colony]]
Grey-headed flying foxes live in a variety of habitats, including [[rainforests]], woodlands, and swamps.<ref name="Menkhorst 1995"/> These camps are variable in size and are seasonally relocated; the warmer parts of the year find them occupying cool and wet gullies in large groups.<ref name="Menkhorst2011" /> 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]], [[mangrove]]s, and [[riparian vegetation]], but roosts also occupy highly modified vegetation in urban areas. A prominent example existed for many years at the [[Royal Botanic Gardens, Sydney|Royal Botanic Gardens]] in [[Sydney]]. However, the botanic gardens instituted a controversial policy to remove them from the garden grounds. The camp is now dispersed across Queensland.<ref>{{cite news |url=http://nqr.farmonline.com.au/news/state/agribusiness-and-general/general/sydneys-flying-foxes-now-bundys-problem/2616870.aspx |title=Sydney's flying foxes now Bundy's problem |publisher=North Queensland Register |date=2 Aug 2012 |accessdate=2014-02-22 }}{{Dead link|date=January 2020 |bot=InternetArchiveBot |fix-attempted=yes }}</ref><ref>{{cite web |url=http://www.australiangeographic.com.au/journal/sydney-bats-to-get-the-boot-after-lost-appeal.htm |title=Say goodbye to Sydney's colony of bats |publisher=Australian Geographic |date=2011-02-17 |accessdate=2014-02-22 |archive-url=https://web.archive.org/web/20131005162338/http://www.australiangeographic.com.au/journal/sydney-bats-to-get-the-boot-after-lost-appeal.htm |archive-date=5 October 2013 |url-status=dead |df=dmy-all }}</ref>
Grey-headed flying foxes live in a variety of habitats, including [[rainforests]], woodlands, and swamps.<ref name="Menkhorst 1995"/> These camps are variable in size and are seasonally relocated; the warmer parts of the year find them occupying cool and wet gullies in large groups.<ref name="Menkhorst2011" /> 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]], [[mangrove]]s, and [[riparian vegetation]], but roosts also occupy highly modified vegetation in urban areas. A prominent example existed for many years at the [[Royal Botanic Gardens, Sydney|Royal Botanic Gardens]] in [[Sydney]]. However, the botanic gardens instituted a controversial policy to remove them from the garden grounds. The camp is now dispersed across Queensland.<ref>{{cite news |url=http://nqr.farmonline.com.au/news/state/agribusiness-and-general/general/sydneys-flying-foxes-now-bundys-problem/2616870.aspx |archive-url=https://archive.today/20121230091602/http://nqr.farmonline.com.au/news/state/agribusiness-and-general/general/sydneys-flying-foxes-now-bundys-problem/2616870.aspx |url-status=dead |archive-date=30 December 2012 |title=Sydney's flying foxes now Bundy's problem |publisher=North Queensland Register |date=2 August 2012 |access-date=2014-02-22 }}</ref><ref>{{cite web |url=http://www.australiangeographic.com.au/journal/sydney-bats-to-get-the-boot-after-lost-appeal.htm |title=Say goodbye to Sydney's colony of bats |publisher=Australian Geographic |date=2011-02-17 |access-date=2014-02-22 |archive-url=https://web.archive.org/web/20131005162338/http://www.australiangeographic.com.au/journal/sydney-bats-to-get-the-boot-after-lost-appeal.htm |archive-date=5 October 2013 |url-status=dead}}</ref>


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. They are [[Keystone species|keystone]] pollinators and seed dispersers of over 100 species of native trees and plants.<ref>"L Pope 2014" / Some Touch of Pity, pub=sid harta</ref> The grey-headed flying fox is a partial migrant that uses winds to facilitate long-distance movement.<ref name="Tidemann 2004"/> It does not migrate in a constant direction, but rather in the direction that will be the most beneficial at the time.<ref name="Tidemann 2004"/>
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. They are [[Keystone species|keystone]] pollinators and seed dispersers of over 100 species of native trees and plants.<ref>"L Pope 2014" / Some Touch of Pity, pub=sid harta</ref> The grey-headed flying fox is a partial migrant that uses winds to facilitate long-distance movement. It does not migrate in a constant direction, but rather in the direction that will be the most beneficial at the time.<ref name="Tidemann 2004"/>


Although recorded in small numbers sporadically throughout the 20th century, it was not until the 1980s that grey-headed flying foxes routinely visited Melbourne,<ref name="pcb" /> with a permanent camp since the 1990s. Their residence at the Melbourne Botanic Garden was the subject of controversy, and the bats were eventually discouraged and moved to [[Yarra Bend]] at the city's river. The camp at this site was decimated during a heat wave, requiring its rehabilitation to sustain the relocated population. The forced relocations are also said to have led to the discovery of the orchards of the [[Goulburn Valley]].{{sfn|Richards|2012|pp=34–35}} Similarly, the first recorded permanent camp in [[Adelaide]] was established in 2010.<ref name="mtlofty" /> The spread is likely due to [[global warming]], habitat loss and drought;<ref name=mtlofty /> while the location of the new camps appears to be in response to [[urbanisation]]: a reliable food supply<ref name=mtlofty /> (such as native eucalypt plantings and backyard fruit trees) and warmer temperatures due to climate change and [[urban heat islands]].<ref name="pcb" />{{sfn|Richards|2012|pp=118}}
Although recorded in small numbers sporadically throughout the 20th century, it was not until the 1980s that grey-headed flying foxes routinely visited Melbourne,<ref name="pcb" /> with a permanent camp since the 1990s. Their residence at the [[Royal Botanic Gardens Victoria]] was the subject of controversy, and the bats were eventually discouraged and moved to [[Yarra Bend]] at the city's river. The camp at this site was decimated during a heat wave, requiring its rehabilitation to sustain the relocated population. The forced relocations are also said to have led to the discovery of the orchards of the [[Goulburn Valley]].{{sfn|Richards|2012|pp=34–35}} Similarly, the first recorded permanent camp in [[Adelaide]] was established in 2010. The spread is likely due to [[global warming]], habitat loss and drought; while the location of the new camps appears to be in response to [[urbanisation]]: a reliable food supply<ref name=mtlofty /> (such as native eucalypt plantings and backyard fruit trees) and warmer temperatures due to climate change and [[urban heat islands]].<ref name="pcb" />{{sfn|Richards|2012|pp=118}}

{{As of|2024}}, the bats have been spreading westward, with camps spotted in [[Port Augusta]], on the [[Eyre Peninsula]], and as far north as [[Katherine, Northern Territory |Katherine]] in the [[Northern Territory]].<ref>{{cite web | last=Hamilton | first=Jodie | last2=Pedler | first2=Emma | title=Flying foxes moving west across Australia in search of homes and food | website=ABC News | date=29 July 2024 | url=https://www.abc.net.au/news/2024-07-29/grey-headed-flying-foxes-moving-west-habitat-loss-food-adelaide/104146304 | access-date=4 August 2024}}</ref>


===Diet and foraging===
===Diet and foraging===
[[File:Grey-headed Flying Fox (IMG0526).jpg|thumb|250px|right|Feeding on plant nectar.]]
[[File:Grey-headed Flying Fox (IMG0526).jpg|thumb|250px|right|Feeding on plant nectar.]]
Around dusk, grey-headed flying foxes leave the roost and travel up to 50&nbsp;km a night to feed on pollen, [[nectar]] and fruit.<ref name="Tidemann 2004">{{Cite journal | doi = 10.1017/S0952836904004960| title = Long-distance movements of the grey-headed flying fox (''Pteropus poliocephalus'')| journal = Journal of Zoology| volume = 263| issue = 2| pages = 141| year = 2004| last1 = Tidemann | first1 = C. R. | last2 = Nelson | first2 = J. E. }}</ref> The species consumes fruit flowers and pollens of around 187 plant species.<ref>{{cite journal | last1 = Williams | first1 = N. S. G. | last2 = McDonnell | first2 = M.J. | last3 = Phelan | first3 = G.K. | last4 = Keim | first4 = L.D. | last5 = der Ree | first5 = R. | year = 2006 | title = Range expansion due to urbanisation, increased food resources attract Grey-headed Flying-foxes (''Pteropus poliocephalus'') to Melbourne | journal = Austral Ecology | volume = 31 | issue = 2| pages = 190–198 | doi=10.1111/j.1442-9993.2006.01590.x}}</ref> These include [[eucalypt]], particularly ''[[Corymbia gummifera]]'', ''[[Eucalyptus muelleriana]]'', ''[[Eucalyptus globoidea|E. globoidea]]'' and ''[[Eucalyptus botryoides|E. botryoides]]'',<ref name="Menkhorst 1995" /><ref name="Parry-Jones 2001">{{Cite journal | doi = 10.1111/j.1442-9993.2001.01072.pp.x| title = Factors affecting the occupation of a colony site in Sydney, New South Wales by the Grey-headed Flying-fox ''Pteropus poliocephalus'' (Pteropodidae)| journal = Austral Ecology| volume = 26| pages = 47| year = 2001| last1 = Parry-Jones | first1 = K. A.| last2 = Augee | first2 = M. L.}}</ref> and fruits from a wide range of rainforest trees, including members of the genus ''[[Ficus]]''.<ref name="Menkhorst 1995"/><ref name="Parry-Jones 2001"/> These bats are considered sequential specialists, since they feed on a variety of foods.<ref name="Parry-Jones 2001"/> 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.
Around dusk, grey-headed flying foxes leave the roost and travel up to 50&nbsp;km a night to feed on pollen, [[nectar]] and fruit.<ref name="Tidemann 2004">{{Cite journal | doi = 10.1017/S0952836904004960| title = Long-distance movements of the grey-headed flying fox (''Pteropus poliocephalus'')| journal = Journal of Zoology| volume = 263| issue = 2| pages = 141| year = 2004| last1 = Tidemann | first1 = C. R. | last2 = Nelson | first2 = J. E. }}</ref> The species consumes fruit flowers and pollens of around 187 plant species.<ref>{{cite journal | last1 = Williams | first1 = N. S. G. | last2 = McDonnell | first2 = M.J. | last3 = Phelan | first3 = G.K. | last4 = Keim | first4 = L.D. | last5 = der Ree | first5 = R. | year = 2006 | title = Range expansion due to urbanisation, increased food resources attract Grey-headed Flying-foxes (''Pteropus poliocephalus'') to Melbourne | journal = Austral Ecology | volume = 31 | issue = 2| pages = 190–198 | doi=10.1111/j.1442-9993.2006.01590.x}}</ref> These include [[eucalypt]], particularly ''[[Corymbia gummifera]]'', ''[[Eucalyptus muelleriana]]'', ''[[Eucalyptus globoidea|E. globoidea]]'' and ''[[Eucalyptus botryoides|E. botryoides]]'',<ref name="Menkhorst 1995" /><ref name="Parry-Jones 2001">{{Cite journal | doi = 10.1111/j.1442-9993.2001.01072.pp.x| title = Factors affecting the occupation of a colony site in Sydney, New South Wales by the Grey-headed Flying-fox ''Pteropus poliocephalus'' (Pteropodidae)| journal = Austral Ecology| volume = 26| pages = 47–55| year = 2001| last1 = Parry-Jones | first1 = K. A.| last2 = Augee | first2 = M. L.}}</ref> and fruits from a wide range of rainforest trees, including members of the genus ''[[Ficus]]''.<ref name="Menkhorst 1995"/><ref name="Parry-Jones 2001"/> These bats are considered sequential specialists, since they feed on a variety of foods.<ref name="Parry-Jones 2001"/> 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.


The teeth, tongue and palate of the [[Pteropodidae|pteropodid]] bats are able to extract plant juices from food, only swallowing smaller seeds of the meal. Incisors hold items such as fruit, and the fibrous material is ejected from the mouth after it is masticated and the juice is swallowed; larger seeds may be held in the mouth and dispersed several kilometres from the tree. The need for the elaborate intestinal tract of most herbivores is consequently removed. Some fruiting plants produce food for flying-foxes, and ''P. poliocephalus'' is attracted to the scent of their flowers and fruit and is able to locate the pale colour that indicates the source; the fruit and blooms of species that attract birds in the daylight are usually contrasting reds and purples. The food source is also presented away from the foliage that may obstruct the bat's access.{{sfn|Richards|2012|p=70}}
The teeth, tongue and palate of the [[Pteropodidae|pteropodid]] bats are able to extract plant juices from food, only swallowing smaller seeds of the meal. Incisors hold items such as fruit, and the fibrous material is ejected from the mouth after it is masticated and the juice is swallowed; larger seeds may be held in the mouth and dispersed several kilometres from the tree. The need for the elaborate intestinal tract of most herbivores is consequently removed. Some fruiting plants produce food for flying-foxes, and ''P. poliocephalus'' is attracted to the scent of their flowers and fruit and is able to locate the pale colour that indicates the source; the fruit and blooms of species that attract birds in the daylight are usually contrasting reds and purples. The food source is also presented away from the foliage that may obstruct the bat's access.{{sfn|Richards|2012|p=70}}


Most of the trees 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.<ref name="Welbergen 2006">{{Cite journal| last1 = Welbergen | first1 = J. A.| title = 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| journal = Behavioral Ecology and Sociobiology| volume = 60| issue = 3| pages = 311–322| year = 2006 | doi = 10.1007/s00265-006-0167-3 |url=https://www.academia.edu/1784389/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}}</ref> Flying foxes have more time and light when foraging if they leave their roosts early in the day.<ref name="Welbergen 2006"/> The entire colony may leave later if a predatory bird is present, while lactating females leave earlier.<ref name="Welbergen 2006"/> With males, the bachelors leave earlier than harem-holding males, which guard and wait until all their females have left.<ref name="Welbergen 2006"/> The flying foxes that leave the roost earlier are more vulnerable to predation, and some flying foxes will wait for others to leave, a phenomenon labelled the "after you" effect.<ref name="Welbergen 2006"/>
Most of the trees 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. Flying foxes have more time and light when foraging if they leave their roosts early in the day. The entire colony may leave later if a predatory bird is present, while lactating females leave earlier. With males, the bachelors leave earlier than harem-holding males, which guard and wait until all their females have left. The flying foxes that leave the roost earlier are more vulnerable to predation, and some flying foxes will wait for others to leave, a phenomenon labelled the "after you" effect.<ref name="Welbergen 2006">{{Cite journal| last1 = Welbergen | first1 = J. A.| title = 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| journal = Behavioral Ecology and Sociobiology| volume = 60| issue = 3| pages = 311–322| year = 2006 | doi = 10.1007/s00265-006-0167-3 | s2cid = 45452998|url=https://www.academia.edu/1784389}}</ref>


===Social organisation===
===Social organisation===
Line 70: Line 73:
Grey-headed flying foxes form two different roosting camps, summer camps and winter camps.<ref name="Nelson 1965">{{cite journal | last1 = Nelson | first1 = J. E. | year = 1965 | title = Behaviour of Australian Pteropodidae (Megachiroptera) | journal = Animal Behaviour | volume = 13 | issue = 4| pages = 544–557 | doi=10.1016/0003-3472(65)90118-1 | pmid=5882814}}</ref> Summer camps are used from September to April or June. In these camps, they establish [[territory (animal)|territories]], [[mating|mate]], and reproduce.<ref name="Nelson 1965"/> Winter camps are used from April to September. The sexes are separated in winter camps and most behaviour is characterised by mutual grooming.<ref name="Nelson 1965"/> Summer camps are considered "main camps", while winter camps are referred to as "transit camps".<ref name="Nelson 1965"/>
Grey-headed flying foxes form two different roosting camps, summer camps and winter camps.<ref name="Nelson 1965">{{cite journal | last1 = Nelson | first1 = J. E. | year = 1965 | title = Behaviour of Australian Pteropodidae (Megachiroptera) | journal = Animal Behaviour | volume = 13 | issue = 4| pages = 544–557 | doi=10.1016/0003-3472(65)90118-1 | pmid=5882814}}</ref> Summer camps are used from September to April or June. In these camps, they establish [[territory (animal)|territories]], [[mating|mate]], and reproduce.<ref name="Nelson 1965"/> Winter camps are used from April to September. The sexes are separated in winter camps and most behaviour is characterised by mutual grooming.<ref name="Nelson 1965"/> Summer camps are considered "main camps", while winter camps are referred to as "transit camps".<ref name="Nelson 1965"/>


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.<ref name="Welbergen 2005">Welbergen, J.A. (2005) "The social organisation of the grey-headed flying-fox". Ph.D thesis, University of Cambridge, Cambridge.</ref> These flying foxes' neck glands enlarge in males in the mating season, and are used to mark the territories.<ref name="Welbergen 2005"/> The males fight to maintain their territories, and this is associated with a steep drop in the males' body condition during this time.<ref name="Welbergen 2011">{{Cite journal | last1 = Welbergen | first1 = J. A. | title = Fit females and fat polygynous males: Seasonal body mass changes in the grey-headed flying fox | doi = 10.1007/s00442-010-1856-1 | journal = Oecologia | volume = 165 | issue = 3 | pages = 629–637 | year = 2011| pmid = 21153744| pmc = }}</ref><ref name="Welbergen 2010">{{cite journal | last1 = Welbergen | first1 = J.A. | year = 2010 | title = Growth, bimaturation, and sexual size dimorphism in wild gray-headed flying foxes (''Pteropus poliocephalus'') | journal = Journal of Mammalogy | volume = 91 | issue = 1| pages = 38–47 | url=http://www.bioone.org/doi/abs/10.1644/09-MAMM-A-157R.1. | doi=10.1644/09-mamm-a-157r.1}}</ref>
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.<ref name="Welbergen 2005">Welbergen, J.A. (2005) "The social organisation of the grey-headed flying-fox". PhD thesis, University of Cambridge, Cambridge.</ref> These flying foxes' neck glands enlarge in males in the mating season, and are used to mark the territories.<ref name="Welbergen 2005"/> The males fight to maintain their territories, and this is associated with a steep drop in the males' body condition during this time.<ref name="Welbergen 2011">{{Cite journal | last1 = Welbergen | first1 = J. A. | title = Fit females and fat polygynous males: Seasonal body mass changes in the grey-headed flying fox | doi = 10.1007/s00442-010-1856-1 | journal = Oecologia | volume = 165 | issue = 3 | pages = 629–637 | year = 2011| pmid = 21153744| bibcode = 2011Oecol.165..629W | s2cid = 13532917 }}</ref><ref name="Welbergen 2010">{{cite journal | last1 = Welbergen | first1 = J.A. | year = 2010 | title = Growth, bimaturation, and sexual size dimorphism in wild gray-headed flying foxes (''Pteropus poliocephalus'') | journal = Journal of Mammalogy | volume = 91 | issue = 1| pages = 38–47 | doi=10.1644/09-mamm-a-157r.1| doi-access = free }}</ref>
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.<ref name="Welbergen 2005"/> Centrally located males are polygamous, while males on the periphery are monogamous or single.<ref name="Nelson 1965"/><ref name="Welbergen 2005"/> The mating system of the grey-headed flying fox is best described as a [[Lek (biology)|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.<ref name="Welbergen 2005"/>
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.<ref name="Welbergen 2005"/> Centrally located males are polygamous, while males on the periphery are monogamous or single.<ref name="Nelson 1965"/><ref name="Welbergen 2005"/> The mating system of the grey-headed flying fox is best described as a [[Lek (biology)|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.<ref name="Welbergen 2005"/>


==== Reproduction ====
==== Reproduction ====
[[File:Grey headed flying fox with pup - AndrewMercer - DSC10055.jpg|thumb|250px|right|Mother with near-mature pup]]
Matings are generally observed between March and May, but the most likely time of conception is April.<ref>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.</ref> 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.<ref>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.</ref> Females usually give birth to one young each year.<ref name="Richards2000" /> [[Gestation]] lasts around 27 weeks,<ref>{{cite journal | last1 = O'Brien | first1 = G.M. | year = 1993 | title = Seasonal reproduction in flying-foxes, reviewed in the context of other tropical mammals | url = | journal = Reproduction Fertility and Development | volume = 5 | issue = 5| pages = 499–521 | doi=10.1071/rd9930499}}</ref> 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.<ref>{{cite journal | last1 = Bartholomew | first1 = G.A. | last2 = Leitner | first2 = P. | last3 = Nelson | first3 = J.E. | year = 1964 | title = Body temperature oxygen consumption and heart rate in three species of Australian flying-foxes | jstor=30152330 | journal = Physiological Zoology | volume = 37 | issue = | pages = 179–198 }}</ref> 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.
Matings are generally observed between March and May, but the most likely time of conception is April.<ref>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.</ref> 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.<ref>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.</ref> Females usually give birth to one young each year.<ref name="Richards2000" /> [[Gestation]] lasts around 27 weeks,<ref>{{cite journal | last1 = O'Brien | first1 = G.M. | year = 1993 | title = Seasonal reproduction in flying-foxes, reviewed in the context of other tropical mammals | journal = Reproduction, Fertility and Development | volume = 5 | issue = 5| pages = 499–521 | doi=10.1071/rd9930499| pmid = 8190905 }}</ref> 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.<ref>{{cite journal | last1 = Bartholomew | first1 = G.A. | last2 = Leitner | first2 = P. | last3 = Nelson | first3 = J.E. | year = 1964 | title = Body temperature oxygen consumption and heart rate in three species of Australian flying-foxes | jstor=30152330 | journal = Physiological Zoology | volume = 37 | issue = 2 | pages = 179–198 | doi = 10.1086/physzool.37.2.30152330 | s2cid = 86940598 }}</ref> 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===
===Predation===
Line 84: Line 88:
The arid climate in parts of the range will prompt the species to seek water in the late afternoon, and this provides an opportunity for freshwater crocodile species ''[[Crocodylus johnstoni]]'' found at the northern parts of the range.
The arid climate in parts of the range will prompt the species to seek water in the late afternoon, and this provides an opportunity for freshwater crocodile species ''[[Crocodylus johnstoni]]'' found at the northern parts of the range.
The 'freshies', as these crocodilians are locally known, will also place themselves beneath the overhanging roosts of this species, and employ a strategy of thrashing at the shoreline to induce panic and aerial collisions. -->{{sfn|Richards|2012|p=104–105}}
The 'freshies', as these crocodilians are locally known, will also place themselves beneath the overhanging roosts of this species, and employ a strategy of thrashing at the shoreline to induce panic and aerial collisions. -->{{sfn|Richards|2012|p=104–105}}
The species was reported by [[John Gould]] as being eaten by the indigenous Australians.<ref name="Gould1863" />
The species was reported by [[John Gould]] as being eaten by [[Indigenous Australians]].<ref name="Gould1863" />


==Conservation==
==Conservation==
[[File:Electrocuted Flying Fox.jpg|thumb|150px|right|A grey-headed flying fox electrocuted between electricity transmission lines in suburban Sydney]]
[[File:Electrocuted Flying Fox.jpg|thumb|150px|right|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, evidence has been accumulating that the species is in serious decline. An estimate for the species in 2019 put the number at 586,000<ref>{{Cite web|url=https://www.environment.gov.au/system/files/pages/391f5fed-e287-4dd3-85ac-640037926ef5/files/flying-fox-may2019-count-report.pdf|title=The National Flying-Fox Monitoring Program|last=Westcott|first=David|date=May 2019|website=Department of the Environment and Energy|url-status=live|archive-url=|archive-date=|access-date=24 December 2019}}</ref> and the national population may have declined by over 30% between 1989 and 1999 alone.<ref>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.</ref>
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, evidence has been accumulating that the species is in serious decline. An estimate for the species in 2019 put the number at 586,000<ref>{{Cite web|url=https://www.environment.gov.au/system/files/pages/391f5fed-e287-4dd3-85ac-640037926ef5/files/flying-fox-may2019-count-report.pdf|title=The National Flying-Fox Monitoring Program|last=Westcott|first=David|date=May 2019|website=Department of the Environment and Energy|access-date=24 December 2019}}</ref> and the national population may have declined by over 30% between 1989 and 1999 alone.<ref>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.</ref>


===Threats===
===Threats===
[[File:Male grey-headed flying fox, suffering from heat stress.jpg|thumb|150px|right|A male grey-headed flying fox, suffering from heat stress during a heatwave in New South Wales]]
Grey-headed flying foxes are exposed to several threats, including loss of foraging and roosting habitat,<ref>Eby, P. (1995). "The biology and management of flying-foxes" in ''NSW. Rep. No. 18. N.S.W. National Parks and Wildlife Service'', Hurstville.</ref> competition with the black flying fox, and mass die-offs caused by extreme temperature events.<ref name="Welbergen 2005"/> 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 [[zoonosis|zoonotic]] [[virus]]es that are potentially fatal to humans: [[Hendra virus]], [[Australian bat lyssavirus]] and [[Menangle virus]].<ref>{{cite journal | last1 = Allworth | first1 = A. | last2 = Murray | first2 = K. | last3 = Morgan | first3 = J.A. | year = 1996 | title = Human case of encephalitis due to a lyssavirus recently identified in fruit bats | url = https://www.health.gov.au/internet/main/publishing.nsf/Content/1996%20issues-1/$FILE/cdi2024a.pdf| journal = Communicable Diseases Intelligence | volume = 20 | issue = | page = 504 }}</ref> However, only Australian bat lyssavirus is known from two isolated cases to be directly transmissible from bats to humans. No person has ever died from ABLV (Lyssavirus) after having had the ABLV post-exposure vaccine.<ref name=pope>{{cite book|last=Pope|first=L.|year=2014|title=Some Touch of Pity|publisher=Sid Harta Publishers}}</ref>
Grey-headed flying foxes are exposed to several threats, including loss of foraging and roosting habitat,<ref>Eby, P. (1995). "The biology and management of flying-foxes" in ''NSW. Rep. No. 18. N.S.W. National Parks and Wildlife Service'', Hurstville.</ref> competition with the black flying fox, and mass die-offs caused by extreme temperature events.<ref name="Welbergen 2005"/> When present in urban environments, grey-headed flying foxes are sometimes perceived as a nuisance. Cultivated orchard fruits are also taken, but apparently only at times when other food items are scarce. Because their roosting and foraging habits bring the species into conflict with humans, they suffer from direct killing of animals in orchards and harassment and destruction of roosts. Negative public perception of the species has intensified with the discovery of three recently emerged [[zoonosis|zoonotic]] [[virus]]es that are potentially fatal to humans: [[Hendra virus]], [[Australian bat lyssavirus]] and [[Menangle virus]].<ref>{{cite journal | last1 = Allworth | first1 = A. | last2 = Murray | first2 = K. | last3 = Morgan | first3 = J.A. | year = 1996 | title = Human case of encephalitis due to a lyssavirus recently identified in fruit bats | url = https://www.health.gov.au/internet/main/publishing.nsf/Content/1996%20issues-1/$FILE/cdi2024a.pdf| journal = Communicable Diseases Intelligence | volume = 20 | page = 504 }}</ref> However, only Australian bat lyssavirus is known from two isolated cases to be directly transmissible from bats to humans. No person has ever died from ABLV (Lyssavirus) after having had the ABLV post-exposure vaccine.<ref name=pope>{{cite book|last=Pope|first=L.|year=2014|title=Some Touch of Pity|publisher=Sid Harta Publishers}}</ref>


The urbanised camps of cities were noted as succumbing to poisoning during the 1970s to 1980s, identified as the [[Tetraethyl lead|lead in petrol]] that would accumulate on the fur and enter the body when grooming. The mortality rate from toxic levels of lead in the environment dropped with the introduction of unleaded fuel in 1985.
The urbanised camps of cities were noted as succumbing to poisoning during the 1970s to 1980s, identified as the [[Tetraethyl lead|lead in petrol]] that would accumulate on the fur and enter the body when grooming. The mortality rate from toxic levels of lead in the environment dropped with the introduction of unleaded fuel in 1985.
An introduced plant, the cocos palm ''[[Syagrus romanzoffiana]]'', now banned by some local councils, bears fruit that is toxic to this species and has resulted in their death; the chinese elm ''[[Ulmus parvifolia]]'' and [[privet]] present this same hazard.
An introduced plant, the cocos palm ''[[Syagrus romanzoffiana]]'', now banned by some local councils, bears fruit that is toxic to this species and has resulted in their death; the Chinese elm ''[[Ulmus parvifolia]]'' and [[privet]] present this same hazard. The species is vulnerable to diseases that may kill large numbers within a camp, and the sudden incidence of premature births in colonies is likely to significantly impact the re-population of the group; the cause of these disorders or diseases in unknown.{{sfn|Richards|2012|pp=107–109}}
The species is vulnerable to diseases that may kill large numbers within a camp, and the sudden incidence of premature births in colonies is likely to significantly impact the re-population of the group; the cause of these disorders or diseases in unknown.{{sfn|Richards|2012|pp=107–109}}
Unsuitable backyard fruit tree netting also kills many animals and may bring them into close contact with humans, but can be avoided by using wildlife-safe netting. [[Barbed wire]] accounts for many casualties; this can be ameliorated by removing old or unnecessary barbed wire or marking it with bright paint.<ref name=pope/>{{sfn|Richards|2012|p=107}}


[[File:Male grey-headed flying fox, suffering from heat stress.jpg|thumb|150px|right|A male grey-headed flying fox, suffering from heat stress during a 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.<ref name="Welbergen et al. 2008">{{Cite journal| last1 = Welbergen | first1 = J.| last2 = Klose | first2 = S.| last3 = Markus | first3 = N.| last4 = Eby | first4 = P.| title = Climate change and the effects of temperature extremes on Australian flying-foxes| journal = Proceedings of the Royal Society B: Biological Sciences| volume = 275| issue = 1633| pages = 419–425| year = 2008| pmid = 18048286 | doi = 10.1098/rspb.2007.1385| pmc = 2596826}}</ref>
Recent research has shown, since 1994, more than 24,500 grey-headed flying foxes have died from extreme heat events alone.<ref name="Welbergen et al. 2008">{{Cite journal| last1 = Welbergen | first1 = J.| last2 = Klose | first2 = S.| last3 = Markus | first3 = N.| last4 = Eby | first4 = P.| title = Climate change and the effects of temperature extremes on Australian flying-foxes| journal = Proceedings of the Royal Society B: Biological Sciences| volume = 275| issue = 1633| pages = 419–425| year = 2008| pmid = 18048286 | doi = 10.1098/rspb.2007.1385| pmc = 2596826}}</ref>
Unsuitable backyard fruit tree netting also kills many animals and may bring them into close contact with humans, but can be avoided by using wildlife-safe netting. [[Barbed wire]] accounts for many casualties; this can be ameliorated by removing old or unnecessary barbed wire or marking it with bright paint.<ref name=pope/>{{sfn|Richards|2012|p=107}}
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,<ref>{{cite web|url=http://www.environment.gov.au/biodiversity/threatened/publications/action/bats/13.html |title=The Action Plan for Australian Bats - Recovery outlines: Grey-headed Flying-fox |publisher=Environment.gov.au |accessdate=2014-02-22}}</ref> 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]].<ref name = IUCN/>


The early twentieth century saw the incursion of ''Pteropus poliocephalus'' to the opportunities they discovered at orchards, and the government placed a bounty on the declared pest.{{sfn|Richards|2012|pp=107–109}} Their reputation for destroying fruit crops was noted by John Gould in 1863,<ref name="Gould1863" /> though the extent of actual damage was often greatly exaggerated. When Ratcliffe submitted his report, he noted the number of paid bounties was 300,000, and this would not have included the mortally wounded escapees or those left suspended at roosts by the grip that is held by their weight. This species continued to be killed or wounded by shotguns, many remaining disabled where they fell after the bounty was stopped, despite the advice of Ratcliffe and later researchers on an ineffective and uneconomical practice and the needless extermination of the population. Orchardists have begun shifting to the use of netting that also discourages the daytime visits of birds. The impact of indiscriminate shooting of bats has resulted in the species being declared vulnerable to extinction, to the tree species that relied on them for regeneration, the subsequent alteration to the forest ecology of the [[Eastern states of Australia|eastern states]]{{sfn|Richards|2012|pp=107–109}}
The early twentieth century saw the incursion of ''Pteropus poliocephalus'' to the opportunities they discovered at orchards, and the government placed a bounty on the declared pest.{{sfn|Richards|2012|pp=107–109}} Their reputation for destroying fruit crops was noted by John Gould in 1863,<ref name="Gould1863" /> though the extent of actual damage was often greatly exaggerated. When Ratcliffe submitted his report, he noted the number of paid bounties was 300,000, and this would not have included the mortally wounded escapees or those left suspended at roosts by the grip that is held by their weight. This species continued to be killed or wounded by shotguns, many remaining disabled where they fell after the bounty was stopped, despite the advice of Ratcliffe and later researchers on an ineffective and uneconomical practice and the needless extermination of the population. Orchardists have begun shifting to the use of netting that also discourages the daytime visits of birds. The impact of indiscriminate shooting of bats has resulted in the species being declared vulnerable to extinction, to the tree species that relied on them for regeneration, the subsequent alteration to the forest ecology of the [[Eastern states of Australia|eastern states]]{{sfn|Richards|2012|pp=107–109}}

===Status and protection===

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,<ref>{{cite web|url=http://www.environment.gov.au/biodiversity/threatened/publications/action/bats/13.html |title=The Action Plan for Australian Bats - Recovery outlines: Grey-headed Flying-fox |publisher=Environment.gov.au |access-date=2014-02-22}}</ref> and has since been protected across its range under Australian federal law, listed as Vulnerable under the ''[[Environment Protection and Biodiversity Conservation Act 1999]]'' (EPBC Act). A [[species recovery plan]] was created by the federal [[Department of Agriculture, Water and the Environment]] and the South Australian [[Department for Environment and Water]] and published in 2021.<ref name=sprat>{{cite web | title=Pteropus poliocephalus — Grey-headed Flying-fox| website=[[Species Profile and Threats Database]]| series=SPRAT Profile | url= https://www.environment.gov.au/cgi-bin/sprat/public/publicspecies.pl?taxon_id=186|publisher= [[Department of Agriculture, Water and the Environment]] (Australia) | access-date=30 December 2021}} [[File:CC-BY icon.svg|50px]] [https://creativecommons.org/licenses/by/4.0 Attribution 4.0 International (CC BY 4.0)] licence.</ref><ref>{{ cite web| url=https://www.awe.gov.au/environment/biodiversity/threatened/publications/recovery/grey-headed-flying-fox| title=National Recovery Plan for the Grey-headed Flying-fox Pteropus poliocephalus| date=2021| publisher= [[Department of Agriculture, Water and the Environment]] (Australia), and the [[Government of South Australia]], [[Department for Environment and Water]] }} [https://www.awe.gov.au/sites/default/files/documents/recovery-plan-grey-headed-flying-fox.pdf PDF]</ref>

{{As of|2021}} the species is listed as "Vulnerable" on the [[IUCN Red List of Threatened Species]] under criteria A2ace and A4ac. Justification for the assessment says that "although the population is relatively large (exceeding 10,000 mature individuals) and it has a large extent of occurrence (> 20,000 km²), a continuing population decline is inferred to be more than 30–35% over the last three generations", and that further decline is expected.<ref name=iucn />


===Wildlife rescue===
===Wildlife rescue===
[[File:Greyheadedflyingfoxbabies2008canungra.jpg|thumb|250px|right|Crib full of abandoned babies rescued by Wildcare Australia in care at The Bat Hospital]]
[[File:Greyheadedflyingfoxbabies2008canungra.jpg|thumb|250px|right|Crib full of abandoned babies rescued by Wildcare Australia in care at The Bat Hospital]]
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, often due to disease or tick paralysis (their own and/or that of the mother).<ref name="Dovas" />
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, F.A.W.N.A. (NSW) Inc., Wildlife ARC, Northern Rivers Wildlife Carers, Northern Tablelands Wildlife Carers, Hunter Wildlife Rescue, Wildlife Aid, Tweed Valley Wildlife Carers, Wildlife Rescue South Coast, [[NSW Wildlife Information and Rescue Service|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 backyard fruit tree netting, both of which can result in very serious injuries and a slow, agonising death for the animal if not rescued quickly. More recently wildlife advocacy groups such the Victorian Advocates for Animals has used the commercial development of a range of wildlife safe fruit tree netting products to push for regulations to make it illegal to install wildlife unsafe nets on backyard fruit trees. These new products have as their chief characteristic small apertures / holes of 5mm x 5mm or less. Flying foxes are able to climb across the netting without being entangled. It is hoped the uptake of wildlife safe netting products will see a marked decline in flying fox entanglements across time and subsequent reduction in public risk and the burden on wildlife rescue and rehabilitation volunteers. An emerging key threatening process to threatened flying-fox populations is the increasing numbers of days when temperatures exceed 41&nbsp;°C, causing mass mortalities in flying-fox camps throughout their range along Australia's eastern seaboard.


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.{{citation needed|date=December 2021}}
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, often due to disease or tick paralysis (their own and/or that of the mother).<ref name="Dovas" /> 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. The NSW Office of Environment and Heritage licences NSW rehabilitation groups under its Biodiversity Conservation Act 2016 and rehabilitation workers to the Code of Practice for Sick, Injured and Orphaned Flying-foxes developed in partnership with NSW Wildlife Council groups and WIRES.


==Gallery==
==Gallery==
Line 123: Line 129:
File:Wensdai4.jpg|Young female grey-headed flying fox playing with her WIRES caretaker
File:Wensdai4.jpg|Young female grey-headed flying fox playing with her WIRES caretaker
File:Grey headed flyng fox444.jpg|Grey-headed flying fox in captivity
File:Grey headed flyng fox444.jpg|Grey-headed flying fox in captivity
File:Grey headed flying fox - skimming water - AndrewMercer - DSC00530.jpg|Skimming water in a pond to drink.
File:Grey headed flying fox - eating figs - AndrewMercer IMG42296.jpg|Eating Figs.
File:Grey headed flying fox - taking off - AndrewMercer IMG41558.jpg|Taking off.
File:Grey headed flying fox - taking off - AndrewMercer IMG41558.jpg|Taking off.
File:Grey-headed flying fox at Parramatta Park, NSW, Australia.jpg|Grey-headed flying fox at Parramatta Park, NSW, Australia
File:Grey-headed flying fox at Parramatta Park, NSW, Australia.jpg|Grey-headed flying fox at Parramatta Park, NSW, Australia
Line 130: Line 134:


==References==
==References==
{{refbegin}}
{{Refbegin}}
*{{cite book |last1=Richards |first1=G.C. |last2=Hall |first2=L.S. |last3=Parish |first3=S. (photography) |title=A natural history of Australian bats: working the night shift |date=2012 |publisher=CSIRO Publishing |isbn=9780643103740 |ref={{sfnRef|Richards|2012}} }}
*{{cite book |last1=Richards |first1=G.C. |last2=Hall |first2=L.S. |last3=Parish |first3=S. (photography) |title=A natural history of Australian bats: working the night shift |date=2012 |publisher=CSIRO Publishing |isbn=9780643103740 |ref={{sfnRef|Richards|2012}} }}
{{refend}}
{{Refend}}
{{Reflist|1|refs=
{{Reflist|1|refs=
<ref name="Gould1863">{{cite book |last1=Gould |first1=J. |title=The mammals of Australia |volume=3 |date=1863 |publisher=Printed by Taylor and Francis, pub. by the author |pages=pl. 28 ''et seq'' |url=https://biodiversitylibrary.org/page/49706063}}</ref>
<ref name="Gould1863">{{cite book |last1=Gould |first1=J. |title=The mammals of Australia |volume=3 |date=1863 |publisher=Printed by Taylor and Francis, pub. by the author |pages=pl. 28 ''et seq'' |url=https://biodiversitylibrary.org/page/49706063}}</ref>
<ref name=mtlofty>[http://www.naturalresources.sa.gov.au/adelaidemtloftyranges/plants-and-animals/native-plants-animals-and-biodiversity/native-animals/mammals/grey-headed-flying-fox/grey-headed-flying-foxes-south-aust Grey-headed Flying-foxes in South Australia], South Australian Department of Natural Resources, (accessed 11-May-2018)</ref>
<ref name=mtlofty>[http://www.naturalresources.sa.gov.au/adelaidemtloftyranges/plants-and-animals/native-plants-animals-and-biodiversity/native-animals/mammals/grey-headed-flying-fox/grey-headed-flying-foxes-south-aust Grey-headed Flying-foxes in South Australia], South Australian Department of Natural Resources, (accessed 11-May-2018)</ref>
<ref name="RCS1859">{{cite book |last1=England |first1=Royal College of Surgeons of |title=Descriptive catalogue of the specimens of natural history in spirit contained in the museum. Vertebrata: Pisces, Reptilia, Aves, Mammalia |date=1859 |page=124 |publisher=Richard Taylor |url=https://biodiversitylibrary.org/page/48325297}}</ref>
<ref name="RCS1859">{{cite book |last1=England |first1=Royal College of Surgeons of |title=Descriptive catalogue of the specimens of natural history in spirit contained in the museum. Vertebrata: Pisces, Reptilia, Aves, Mammalia |date=1859 |page=124 |publisher=Richard Taylor |url=https://biodiversitylibrary.org/page/48325297}}</ref>
<ref name="pcb">{{cite web|title=Practical Conservation Biology|url=https://books.google.com/books?id=syrqsTQVWC8C&lpg=PA247&ots=5xNDmB3gIl&dq=when%20%20did%20flying%20foxes%20arrive%20in%20melbourne&pg=PA247#v=onepage&q&f=false|work=[[Google Books]]|publisher=[[CSIRO Publishing]]|accessdate=29 January 2014|author=David Lindenmayer|author2=Mark A. Burgman|page=247|year=2005}}</ref>
<ref name="pcb">{{cite book|title=Practical Conservation Biology|url=https://books.google.com/books?id=syrqsTQVWC8C&pg=PA247|publisher=[[CSIRO Publishing]]|author=David Lindenmayer|author2=Mark A. Burgman|page=247|year=2005|isbn = 9780643090897}}</ref>
<ref name="Richards2000">{{cite book |author1=Hall, L. S. |author2=Richards, G. C. |title=Flying-foxes: fruit and blossom bats of Australia |publisher=University of New South Wales Press |location=Sydney |year=2000 |isbn=0-86840-561-2}}</ref>
<ref name="Richards2000">{{cite book |author1=Hall, L. S. |author2=Richards, G. C. |title=Flying-foxes: fruit and blossom bats of Australia |publisher=University of New South Wales Press |location=Sydney |year=2000 |isbn=0-86840-561-2}}</ref>
<ref name="Menkhorst2011">{{cite book |last1=Menkhorst |first1=P.W. |last2=Knight |first2=F. |authorlink1=Peter Menkhorst |author2link=Frank Knight |title=A field guide to the mammals of Australia |date=2011 |publisher=Oxford University Press |location=Melbourne |isbn=9780195573954 |page=146 |edition=3rd}}</ref>
<ref name="Menkhorst2011">{{cite book |last1=Menkhorst |first1=P.W. |last2=Knight |first2=F. |author-link1=Peter Menkhorst |author2-link=Frank Knight |title=A field guide to the mammals of Australia |date=2011 |publisher=Oxford University Press |location=Melbourne |isbn=9780195573954 |page=146 |edition=3rd}}</ref>

<ref name = IUCN>{{Cite iucn | author = Lunney, D. | author2 = Richards, G. | author3 = Dickman, C. | last-author-amp = yes | title = ''Pteropus poliocephalus'' | volume = 2008 | page = e.T18751A8554062 | date = 2008 | doi = 10.2305/IUCN.UK.2008.RLTS.T18751A8554062.en }}</ref>
<ref name="Menkhorst 1995">Menkhorst, P. 1995. "Grey-headed Flying-fox". pp. 156–158 in P. Menkhorst, ed. ''Mammals of Victoria''. Melbourne: Oxford University Press.</ref>
<ref name="Menkhorst 1995">Menkhorst, P. 1995. "Grey-headed Flying-fox". pp. 156–158 in P. Menkhorst, ed. ''Mammals of Victoria''. Melbourne: Oxford University Press.</ref>
<ref name="Temminck1824">{{cite book |last1=Temminck |first1=C.J. |title=Monographie de mammalogie |date=1824 |location=Paris |url=https://biodiversitylibrary.org/page/52681325 |language=French}}</ref>
<ref name="Temminck1824">{{cite book |last1=Temminck |first1=C.J. |title=Monographie de mammalogie |date=1824 |location=Paris |url=https://biodiversitylibrary.org/page/52681325 |language=fr}}</ref>
<ref name="Dovas">{{cite web|author=Dovas|title=There’s A Bat Hospital In Australia That Takes In Abandoned Baby Bats|url=https://www.boredpanda.com/abandoned-baby-bat-pup-tolga-bat-hospital/|publisher=Bored Panda|accessdate=12 December 2017}}</ref>
<ref name="Dovas">{{cite web|author=Dovas|title=There's A Bat Hospital in Australia That Takes in Abandoned Baby Bats|url=https://www.boredpanda.com/abandoned-baby-bat-pup-tolga-bat-hospital/|publisher=Bored Panda|access-date=12 December 2017}}</ref>
}}
}}


==Further reading==
==Further reading==
* {{cite conference |author=Eby, P. |title=The results of four synchronous assessments of relative distribution and abundance of Grey-headed Flying-fox ''Pteropus poliocephalus'' |editor=Hall, L. |booktitle=Proceedings of a Workshop to Assess the Status of the Grey-headed Flying-Fox |pages= |publisher=Australasian Bat Society |year=2000 |location=Canberra }}
* {{cite conference |author=Eby, P. |title=The results of four synchronous assessments of relative distribution and abundance of Grey-headed Flying-fox ''Pteropus poliocephalus'' |editor=Hall, L. |book-title=Proceedings of a Workshop to Assess the Status of the Grey-headed Flying-Fox |publisher=Australasian Bat Society |year=2000 |location=Canberra }}

*{{cite journal |author=Nelson, J. E. W. |title=Behavior of Australian ''Pteropodidae'' (''Megachiroptera'') |journal=Animal Behaviour |volume=13 |pages=544–557 |year=1965 |doi=10.1016/0003-3472(65)90118-1 |pmid=5882814 |issue=4}}
*{{cite journal |author=Nelson, J. E. W. |title=Behavior of Australian ''Pteropodidae'' (''Megachiroptera'') |journal=Animal Behaviour |volume=13 |pages=544–557 |year=1965 |doi=10.1016/0003-3472(65)90118-1 |pmid=5882814 |issue=4}}
* {{cite journal |author=Tidemann, C. R. |title=Biology and management of the grey-headed flying-fox, ''Pteropus poliocephalus'' |journal=Acta Chiropterologica |volume=1 |pages=151–164 |year=1999}}
* {{cite journal |author=Tidemann, C. R. |title=Biology and management of the grey-headed flying-fox, ''Pteropus poliocephalus'' |journal=Acta Chiropterologica |volume=1 |pages=151–164 |year=1999}}
*{{Cite journal| last1 = Welbergen | first1 = J.| last2 = Klose | first2 = S.| last3 = Markus | first3 = N.| last4 = Eby | first4 = P.| title = Climate change and the effects of temperature extremes on Australian flying-foxes| journal = Proceedings of the Royal Society B: Biological Sciences| volume = 275| issue = 1633| pages = 419–425| year = 2008| pmid = 18048286 | doi = 10.1098/rspb.2007.1385| pmc = 2596826}}
*{{Cite journal| last1 = Welbergen | first1 = J.| last2 = Klose | first2 = S.| last3 = Markus | first3 = N.| last4 = Eby | first4 = P.| title = Climate change and the effects of temperature extremes on Australian flying-foxes| journal = Proceedings of the Royal Society B: Biological Sciences| volume = 275| issue = 1633| pages = 419–425| year = 2008| pmid = 18048286 | doi = 10.1098/rspb.2007.1385| pmc = 2596826}}
* {{Cite journal | last1 = Klose | first1 = S. M. | last2 = Welbergen | first2 = J. A. | last3 = Kalko | first3 = E. K. V. | title = Testosterone is associated with harem maintenance ability in free-ranging grey-headed flying-foxes, ''Pteropus poliocephalus'' | journal = Biology Letters | volume = 5 | pages = 758 | year = 2009 | doi = 10.1098/rsbl.2009.0563 | pmid=19689980 | pmc=2828011}}
* {{Cite journal | last1 = Klose | first1 = S. M. | last2 = Welbergen | first2 = J. A. | last3 = Kalko | first3 = E. K. V. | title = Testosterone is associated with harem maintenance ability in free-ranging grey-headed flying-foxes, ''Pteropus poliocephalus'' | journal = Biology Letters | volume = 5 | pages = 758–761 | year = 2009 | issue = 6 | doi = 10.1098/rsbl.2009.0563 | pmid=19689980 | pmc=2828011}}
* {{Cite journal| last1 = Klose | first1 = S. M.| last2 = Welbergen | first2 = J. A.| last3 = Goldizen | first3 = A. W.| last4 = Kalko | first4 = E. K. V.| title = Spatio-temporal vigilance architecture of an Australian flying-fox colony| journal = Behavioral Ecology and Sociobiology| volume = 63| issue = 3| pages = 371| year = 2008| doi = 10.1007/s00265-008-0671-8}}
* {{Cite journal| last1 = Klose | first1 = S. M.| last2 = Welbergen | first2 = J. A.| last3 = Goldizen | first3 = A. W.| last4 = Kalko | first4 = E. K. V.| title = Spatio-temporal vigilance architecture of an Australian flying-fox colony| journal = Behavioral Ecology and Sociobiology| volume = 63| issue = 3| pages = 371| year = 2008| doi = 10.1007/s00265-008-0671-8| s2cid = 23935034}}


==External links==
==External links==
{{Wikispecies|Pteropus poliocephalus}}
{{Wikispecies|Pteropus poliocephalus}}
{{Commonscat|Pteropus poliocephalus}}
{{Commons category|Pteropus poliocephalus}}
* ARKive - [https://web.archive.org/web/20060509183833/http://www.arkive.org/species/GES/mammals/Pteropus_poliocephalus/ images and movies of the grey-headed flying-fox ''(Pteropus poliocephalus)'']
* ARKive - [https://web.archive.org/web/20060509183833/http://www.arkive.org/species/GES/mammals/Pteropus_poliocephalus/ images and movies of the grey-headed flying-fox ''(Pteropus poliocephalus)'']
* [https://web.archive.org/web/20071124073627/http://www.zoo.cam.ac.uk/zoostaff/bbe/Welbergen/GHFlyingFox.htm Background: ''P. poliocephalus'']
* [https://web.archive.org/web/20071124073627/http://www.zoo.cam.ac.uk/zoostaff/bbe/Welbergen/GHFlyingFox.htm Background: ''P. poliocephalus'']
Line 164: Line 167:


{{Pteropodidae|P.}}
{{Pteropodidae|P.}}
{{Use dmy dates|date=July 2011}}

{{Taxonbar|from=Q551930}}
{{Taxonbar|from=Q551930}}


[[Category:Pteropus]]
[[Category:Pteropus]]
[[Category:Pollinator bats]]
[[Category:Bats of Australia]]
[[Category:Bats of Australia]]
[[Category:Vulnerable fauna of Australia]]
[[Category:Vulnerable fauna of Australia]]
Line 175: Line 175:
[[Category:Mammals of Queensland]]
[[Category:Mammals of Queensland]]
[[Category:Mammals of New South Wales]]
[[Category:Mammals of New South Wales]]
[[Category:Mammals of Victoria (Australia)]]
[[Category:Mammals of Victoria (state)]]
[[Category:Urban animals]]
[[Category:Mammals described in 1825]]
[[Category:Mammals described in 1825]]
[[Category:Taxa named by Coenraad Jacob Temminck]]
[[Category:Taxa named by Coenraad Jacob Temminck]]

Latest revision as of 22:46, 4 August 2024

Grey-headed flying fox
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Chiroptera
Family: Pteropodidae
Genus: Pteropus
Species:
P. poliocephalus
Binomial name
Pteropus poliocephalus
Native distribution of Pteropus poliocephalus

The grey-headed flying fox (Pteropus poliocephalus) is a megabat native to Australia.[3] The species shares mainland Australia with three other members of the genus Pteropus: the little red P. scapulatus, spectacled P. conspicillatus, and the black P. alecto. The grey-headed flying fox is the largest bat in Australia.

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 in Queensland 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.

As of 2021 the species is listed as "Vulnerable" on the IUCN Red List of Threatened Species.[1]

Taxonomy

[edit]

A description of the species was published by Coenraad Temminck in his 1825 monograph of mammals. Hybridisation with the species Pteropus alecto has been noted where their ranges intersect.[3]

The common names for Pteropus poliocephalus include grey-headed kalong.[4] The entry in Gould's Mammals of Australia (1863) gave the bat the title grey-headed vampire.[5]

Description

[edit]
Wingspan is visible as this flying fox skims water to drink.

The grey-headed flying fox is the largest bat in Australia, with the adult wingspan reaching up to 1 m (3 ft 3 in) in length and weighing up to 1 kg (2.2 lb).[6] Weight generally varies between 600 and 1,000 g (21 and 35 oz), with an average of 700 g (25 oz). The combined length of the head and body is from 230 to 290 mm. The forearm length is a range from 138 to 180 mm. The length of the ear from the tip to base is 30 to 37 mm.[7]

The overall colour of the pelage is a dark-grey body with a light-grey head, separated by a reddish-brown collar. The fur on the body is long and streaked with grey, the broad and well defined collar completely encircles the neck with hair that is golden orange in tone. A unique characteristic among bats of the genus Pteropus is fur on the legs that extends all the way to the ankle.[7]

Like many megachiropterans, the species lacks a tail. All of these bats possess claws on its first and second digits. The head is simple in form, with the characteristic 'dog-like' appearance of the genus. Since it does not echolocate, it lacks the tragus or leaf ornamentation found in many species of Microchiroptera. It relies on smell and, predominately, sight to locate its food (nectar, pollen and native fruits) and thus has relatively large eyes for a bat.

The voice of P. poliocephalus consists of a complex series of squeals and screechings.[7] They will flap their wings in hot weather, using blood pumped through the patagium to cool the body temperature.[8]

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]

Grey-headed flying foxes have been found to experience torpor.[9]

Ecology

[edit]

Distribution

[edit]

The distribution range is at the eastern regions of the Australian continent, mostly within 200 kilometres of the coast, from Gladstone in Queensland through to the southern Gippsland region and populations around the city of Melbourne. The breeding range has been recorded as progressing southward, the temperate climate of Melbourne and Geelong and no further north than Maryborough, Queensland.[7]

Urbanisation may displace the species, or provide habitat that accommodates their feeding or roosting preferences. The city of Brisbane has many roosts occupied by the species; a famous colony at the Indooroopilly Island is noted for the evening departure of the bats across the local river. Within the central business district of Sydney, they can be seen travelling along city streets to feed at Moreton Bay fig trees at Hyde Park.[10] The species was recorded as an occasional visitor to the national capital Canberra, although the flowering eucalypts at Commonwealth Park have seen more permanent camps established close to the city.[11]

The species was surveyed during the 1920s by Francis Ratcliffe, who recorded the populations in estimates of quarter, half, or one million in camps, generally located around 40 kilometres apart. These numbers have greatly declined since this first survey.[12]

Habitat and movements

[edit]
Grey-headed flying fox colony

Grey-headed flying foxes live in a variety of habitats, including rainforests, woodlands, and swamps.[13] These camps are variable in size and are seasonally relocated; the warmer parts of the year find them occupying cool and wet gullies in large groups.[7] 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 for many years at the Royal Botanic Gardens in Sydney. However, the botanic gardens instituted a controversial policy to remove them from the garden grounds. The camp is now dispersed across Queensland.[14][15]

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. They are keystone pollinators and seed dispersers of over 100 species of native trees and plants.[16] The grey-headed flying fox is a partial migrant that uses winds to facilitate long-distance movement. It does not migrate in a constant direction, but rather in the direction that will be the most beneficial at the time.[17]

Although recorded in small numbers sporadically throughout the 20th century, it was not until the 1980s that grey-headed flying foxes routinely visited Melbourne,[18] with a permanent camp since the 1990s. Their residence at the Royal Botanic Gardens Victoria was the subject of controversy, and the bats were eventually discouraged and moved to Yarra Bend at the city's river. The camp at this site was decimated during a heat wave, requiring its rehabilitation to sustain the relocated population. The forced relocations are also said to have led to the discovery of the orchards of the Goulburn Valley.[19] Similarly, the first recorded permanent camp in Adelaide was established in 2010. The spread is likely due to global warming, habitat loss and drought; while the location of the new camps appears to be in response to urbanisation: a reliable food supply[20] (such as native eucalypt plantings and backyard fruit trees) and warmer temperatures due to climate change and urban heat islands.[18][21]

As of 2024, the bats have been spreading westward, with camps spotted in Port Augusta, on the Eyre Peninsula, and as far north as Katherine in the Northern Territory.[22]

Diet and foraging

[edit]
Feeding on plant nectar.

Around dusk, grey-headed flying foxes leave the roost and travel up to 50 km a night to feed on pollen, nectar and fruit.[17] The species consumes fruit flowers and pollens of around 187 plant species.[23] These include eucalypt, particularly Corymbia gummifera, Eucalyptus muelleriana, E. globoidea and E. botryoides,[13][24] and fruits from a wide range of rainforest trees, including members of the genus Ficus.[13][24] These bats are considered sequential specialists, since they feed on a variety of foods.[24] 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.

The teeth, tongue and palate of the pteropodid bats are able to extract plant juices from food, only swallowing smaller seeds of the meal. Incisors hold items such as fruit, and the fibrous material is ejected from the mouth after it is masticated and the juice is swallowed; larger seeds may be held in the mouth and dispersed several kilometres from the tree. The need for the elaborate intestinal tract of most herbivores is consequently removed. Some fruiting plants produce food for flying-foxes, and P. poliocephalus is attracted to the scent of their flowers and fruit and is able to locate the pale colour that indicates the source; the fruit and blooms of species that attract birds in the daylight are usually contrasting reds and purples. The food source is also presented away from the foliage that may obstruct the bat's access.[25]

Most of the trees 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. Flying foxes have more time and light when foraging if they leave their roosts early in the day. The entire colony may leave later if a predatory bird is present, while lactating females leave earlier. With males, the bachelors leave earlier than harem-holding males, which guard and wait until all their females have left. The flying foxes that leave the roost earlier are more vulnerable to predation, and some flying foxes will wait for others to leave, a phenomenon labelled the "after you" effect.[26]

Social organisation

[edit]

Groupings and territories

[edit]

Grey-headed flying foxes form two different roosting camps, summer camps and winter camps.[27] Summer camps are used from September to April or June. In these camps, they establish territories, mate, and reproduce.[27] Winter camps are used from April to September. The sexes are separated in winter camps and most behaviour is characterised by mutual grooming.[27] Summer camps are considered "main camps", while winter camps are referred to as "transit camps".[27]

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.[28] These flying foxes' neck glands enlarge in males in the mating season, and are used to mark the territories.[28] The males fight to maintain their territories, and this is associated with a steep drop in the males' body condition during this time.[29][30] 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.[28] Centrally located males are polygamous, while males on the periphery are monogamous or single.[27][28] 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.[28]

Reproduction

[edit]
Mother with near-mature pup

Matings are generally observed between March and May, but the most likely time of conception is April.[31] 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.[32] Females usually give birth to one young each year.[33] Gestation lasts around 27 weeks,[34] 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.[35] 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.[27]

The camps of P. poliocephalus attract a number of larger predators. including both terrestrial and aerial hunters. The sea eagle Haliaeetus leucogaster will capture these bats in flight as they leave their roosts. The snake species Morelia spilota is frequently found as a resident at these camps, lazily selecting an individual from the apparently unconcerned group at a branch. The bat is seized in the jaws and encircled by the python's body, then swallowed head first to be digested over the next week.[36] The species was reported by John Gould as being eaten by Indigenous Australians.[5]

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, evidence has been accumulating that the species is in serious decline. An estimate for the species in 2019 put the number at 586,000[37] and the national population may have declined by over 30% between 1989 and 1999 alone.[38]

Threats

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

Grey-headed flying foxes are exposed to several threats, including loss of foraging and roosting habitat,[39] competition with the black flying fox, and mass die-offs caused by extreme temperature events.[28] 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.[40] However, only Australian bat lyssavirus is known from two isolated cases to be directly transmissible from bats to humans. No person has ever died from ABLV (Lyssavirus) after having had the ABLV post-exposure vaccine.[41]

The urbanised camps of cities were noted as succumbing to poisoning during the 1970s to 1980s, identified as the lead in petrol that would accumulate on the fur and enter the body when grooming. The mortality rate from toxic levels of lead in the environment dropped with the introduction of unleaded fuel in 1985. An introduced plant, the cocos palm Syagrus romanzoffiana, now banned by some local councils, bears fruit that is toxic to this species and has resulted in their death; the Chinese elm Ulmus parvifolia and privet present this same hazard. The species is vulnerable to diseases that may kill large numbers within a camp, and the sudden incidence of premature births in colonies is likely to significantly impact the re-population of the group; the cause of these disorders or diseases in unknown.[42]

Recent research has shown, since 1994, more than 24,500 grey-headed flying foxes have died from extreme heat events alone.[43] Unsuitable backyard fruit tree netting also kills many animals and may bring them into close contact with humans, but can be avoided by using wildlife-safe netting. Barbed wire accounts for many casualties; this can be ameliorated by removing old or unnecessary barbed wire or marking it with bright paint.[41][12]

The early twentieth century saw the incursion of Pteropus poliocephalus to the opportunities they discovered at orchards, and the government placed a bounty on the declared pest.[42] Their reputation for destroying fruit crops was noted by John Gould in 1863,[5] though the extent of actual damage was often greatly exaggerated. When Ratcliffe submitted his report, he noted the number of paid bounties was 300,000, and this would not have included the mortally wounded escapees or those left suspended at roosts by the grip that is held by their weight. This species continued to be killed or wounded by shotguns, many remaining disabled where they fell after the bounty was stopped, despite the advice of Ratcliffe and later researchers on an ineffective and uneconomical practice and the needless extermination of the population. Orchardists have begun shifting to the use of netting that also discourages the daytime visits of birds. The impact of indiscriminate shooting of bats has resulted in the species being declared vulnerable to extinction, to the tree species that relied on them for regeneration, the subsequent alteration to the forest ecology of the eastern states[42]

Status and protection

[edit]

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,[44] and has since been protected across its range under Australian federal law, listed as Vulnerable under the Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act). A species recovery plan was created by the federal Department of Agriculture, Water and the Environment and the South Australian Department for Environment and Water and published in 2021.[45][46]

As of 2021 the species is listed as "Vulnerable" on the IUCN Red List of Threatened Species under criteria A2ace and A4ac. Justification for the assessment says that "although the population is relatively large (exceeding 10,000 mature individuals) and it has a large extent of occurrence (> 20,000 km²), a continuing population decline is inferred to be more than 30–35% over the last three generations", and that further decline is expected.[1]

Wildlife rescue

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

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, often due to disease or tick paralysis (their own and/or that of the mother).[47]

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.[citation needed]

[edit]

References

[edit]
  • Richards, G.C.; Hall, L.S.; Parish, S. (photography) (2012). A natural history of Australian bats: working the night shift. CSIRO Publishing. ISBN 9780643103740.
  1. ^ a b c Eby, P.; Roberts, B.; Pennay, M.; Welbergen, J.A. (2021). "Pteropus poliocephalus". IUCN Red List of Threatened Species. 2021: e.T18751A22085511. doi:10.2305/IUCN.UK.2021-3.RLTS.T18751A22085511.en. Retrieved 12 December 2021.
  2. ^ Temminck, C.J. (1824). Monographie de mammalogie (in French). Paris.
  3. ^ a b Simmons, N.B. (2005). "Order Chiroptera". In Wilson, D.E.; Reeder, D.M (eds.). Mammal Species of the World: A Taxonomic and Geographic Reference (3rd ed.). Johns Hopkins University Press. p. 342. ISBN 978-0-8018-8221-0. OCLC 62265494.
  4. ^ England, Royal College of Surgeons of (1859). Descriptive catalogue of the specimens of natural history in spirit contained in the museum. Vertebrata: Pisces, Reptilia, Aves, Mammalia. Richard Taylor. p. 124.
  5. ^ a b c Gould, J. (1863). The mammals of Australia. Vol. 3. Printed by Taylor and Francis, pub. by the author. pp. pl. 28 et seq.
  6. ^ "Grey-headed Flying-fox - profile". NSW Environment, Energy and Science. 2 June 2014. Retrieved 30 December 2021.
  7. ^ a b c d e Menkhorst, P.W.; Knight, F. (2011). A field guide to the mammals of Australia (3rd ed.). Melbourne: Oxford University Press. p. 146. ISBN 9780195573954.
  8. ^ Richards 2012, p. 50.
  9. ^ Turbill, Christopher; Walker, Melissa; Boardman, Wayne; Martin, John M.; McKeown, Adam; Meade, Jessica; Welbergen, Justin A. (10 July 2024). "Torpor use in the wild by one of the world's largest bats". Proceedings of the Royal Society B: Biological Sciences. 291 (2026). doi:10.1098/rspb.2024.1137. ISSN 1471-2954.
  10. ^ Richards 2012, pp. 28–30.
  11. ^ Richards 2012, p. 33.
  12. ^ a b Richards 2012, p. 107.
  13. ^ a b c Menkhorst, P. 1995. "Grey-headed Flying-fox". pp. 156–158 in P. Menkhorst, ed. Mammals of Victoria. Melbourne: Oxford University Press.
  14. ^ "Sydney's flying foxes now Bundy's problem". North Queensland Register. 2 August 2012. Archived from the original on 30 December 2012. Retrieved 22 February 2014.
  15. ^ "Say goodbye to Sydney's colony of bats". Australian Geographic. 17 February 2011. Archived from the original on 5 October 2013. Retrieved 22 February 2014.
  16. ^ "L Pope 2014" / Some Touch of Pity, pub=sid harta
  17. ^ a b Tidemann, C. R.; Nelson, J. E. (2004). "Long-distance movements of the grey-headed flying fox (Pteropus poliocephalus)". Journal of Zoology. 263 (2): 141. doi:10.1017/S0952836904004960.
  18. ^ a b David Lindenmayer; Mark A. Burgman (2005). Practical Conservation Biology. CSIRO Publishing. p. 247. ISBN 9780643090897.
  19. ^ Richards 2012, pp. 34–35.
  20. ^ Grey-headed Flying-foxes in South Australia, South Australian Department of Natural Resources, (accessed 11-May-2018)
  21. ^ Richards 2012, pp. 118.
  22. ^ Hamilton, Jodie; Pedler, Emma (29 July 2024). "Flying foxes moving west across Australia in search of homes and food". ABC News. Retrieved 4 August 2024.
  23. ^ 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 (2): 190–198. doi:10.1111/j.1442-9993.2006.01590.x.
  24. ^ a b c Parry-Jones, K. A.; Augee, M. L. (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: 47–55. doi:10.1111/j.1442-9993.2001.01072.pp.x.
  25. ^ Richards 2012, p. 70.
  26. ^ 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. S2CID 45452998.
  27. ^ a b c d e f Nelson, J. E. (1965). "Behaviour of Australian Pteropodidae (Megachiroptera)". Animal Behaviour. 13 (4): 544–557. doi:10.1016/0003-3472(65)90118-1. PMID 5882814.
  28. ^ a b c d e f Welbergen, J.A. (2005) "The social organisation of the grey-headed flying-fox". PhD thesis, University of Cambridge, Cambridge.
  29. ^ 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. Bibcode:2011Oecol.165..629W. doi:10.1007/s00442-010-1856-1. PMID 21153744. S2CID 13532917.
  30. ^ 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.
  31. ^ 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.
  32. ^ 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.
  33. ^ 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.
  34. ^ O'Brien, G.M. (1993). "Seasonal reproduction in flying-foxes, reviewed in the context of other tropical mammals". Reproduction, Fertility and Development. 5 (5): 499–521. doi:10.1071/rd9930499. PMID 8190905.
  35. ^ 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 (2): 179–198. doi:10.1086/physzool.37.2.30152330. JSTOR 30152330. S2CID 86940598.
  36. ^ Richards 2012, p. 104–105.
  37. ^ Westcott, David (May 2019). "The National Flying-Fox Monitoring Program" (PDF). Department of the Environment and Energy. Retrieved 24 December 2019.
  38. ^ 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.
  39. ^ Eby, P. (1995). "The biology and management of flying-foxes" in NSW. Rep. No. 18. N.S.W. National Parks and Wildlife Service, Hurstville.
  40. ^ Allworth, A.; Murray, K.; Morgan, J.A. (1996). "Human case of encephalitis due to a lyssavirus recently identified in fruit bats" (PDF). Communicable Diseases Intelligence. 20: 504.
  41. ^ a b Pope, L. (2014). Some Touch of Pity. Sid Harta Publishers.
  42. ^ a b c Richards 2012, pp. 107–109.
  43. ^ Welbergen, J.; Klose, S.; Markus, N.; Eby, P. (2008). "Climate change and the effects of temperature extremes on Australian flying-foxes". Proceedings of the Royal Society B: Biological Sciences. 275 (1633): 419–425. doi:10.1098/rspb.2007.1385. PMC 2596826. PMID 18048286.
  44. ^ "The Action Plan for Australian Bats - Recovery outlines: Grey-headed Flying-fox". Environment.gov.au. Retrieved 22 February 2014.
  45. ^ "Pteropus poliocephalus — Grey-headed Flying-fox". Species Profile and Threats Database. SPRAT Profile. Department of Agriculture, Water and the Environment (Australia). Retrieved 30 December 2021. Attribution 4.0 International (CC BY 4.0) licence.
  46. ^ "National Recovery Plan for the Grey-headed Flying-fox Pteropus poliocephalus". Department of Agriculture, Water and the Environment (Australia), and the Government of South Australia, Department for Environment and Water. 2021. PDF
  47. ^ Dovas. "There's A Bat Hospital in Australia That Takes in Abandoned Baby Bats". Bored Panda. Retrieved 12 December 2017.

Further reading

[edit]
[edit]