The forests, waterways and grasslands of the Park provide a haven for native bats. One species of megabat and nine species of microbats have been recorded to date.
Megabats (such as the Grey-headed Flying-fox) are generally large bats, with wingspans of up to one metre. They eat mainly nectar and fruit, and rely on acute night vision and a keen sense of smell to locate food trees. They do not use ultrasound to navigate and find food like their smaller relatives. During the day these large bats hang from branches in camps located in rainforest gullies or along rivers or creeks. One young is born fully furred and alert and it is not unusual to observe the young scanning their surroundings as they are being delivered.
Microchiropteran bats (microbats) are small, mostly insectivorous bats that roost by day and hunt at night, navigating by echolocation. Nine microbat species have been recorded at Sydney Olympic Park in recent years; this is a high proportion of the total number of microbat species known to occur within the Sydney area and included two threatened species (Large Bent-wing Bat and Lesser Bent-wing Bat), as well as the only known Sydney maternity colony of the White-striped Free-tailed Bat.
Most microbats are small, averaging 9cm in length, weigh less than 13 grams and have a wingspan of less than 25cm. All but a few species are insectivorous. The actual types and size of insects eaten vary considerably between different bat species, varying from mosquitoes to moths to beetles. Microbats can eat up to half their bodyweight in insects per night, which in some cases may consist of several hundred insects. Habitat usage also differs greatly between species; some hunt for insects amongst the foliage in low-level forested areas, while others hunt high in the canopy, others hunt in open areas and above waterbodies, and some hunt around artificial lights where they are often seen catching moths attracted to the light.
Microbat surveys were undertaken at Sydney Olympic Park in 2002 and 2006. The 2002 survey also involved radio-tracking of some individuals, which resulted in identification of microbat roosting sites in buildings and in the woodland of Newington Nature Reserve. Both surveys included detailed inspections of buildings within Newington Armory for signs of use by bats, with several buildings close to Newington Nature Reserve showing evidence of recent use as maternity roosts.
Species that have been recorded within Sydney Olympic Park since 2002 are:
Of these, the Large Bent-wing Bat and the Little Bent-wing Bat appear to be seasonal visitors to Sydney Olympic Park as they have only been recorded at the Park during autumn and winter. The other species are recorded within the Park year-round; four of these are known to rely on the Park for breeding habitat.
By day, microbats normally roost within the hollows of live or dead trees, under bark, or within caves. Within urbanised areas where natural habitat is less available, many bats roost within the roof or wall cavities of buildings, stormwater drains and other man-made structures. During the breeding season, females congregate in ‘maternity roosts’ for several months until their young are able to leave the roost. Maternity roosts vary considerably in size between the various species, from a few individuals to many thousands. Roof and wall cavities of some of the heritage buildings in Newington Armory at Sydney Olympic Park are used as maternity roosts by the White-striped Free-tailed Bat, the Lesser Long-eared Bat, Gould’s Wattled Bat and the Little Freetail Bat.
Microbats have been recorded across all areas of the Parklands and within the Town Centre. However, core breeding, roosting and feeding habitats are within Newington Nature Reserve and the Newington Armory buffer zone. The Brickpit and Narawang Wetland also support high numbers and diversity of microbats.
Both the Large Bent-wing Bat and the Little Bent-wing Bat are listed as vulnerable species under the NSW Threatened Species Conservation Act 1995.
Some bat species have adapted well to urban environments, but many microbat species are in decline around Sydney. It is likely that up to 17 species of bats would have inhabited the area of Sydney Olympic Park at the time of first European settlement.
Breeding sites are generally poorly known, and any identified maternity roosts are of high conservation significance. The presence of a large maternity colony of the White-striped Free-tailed bat within a building at Newington Armory is of particular significance - this species – which is normally a hollow-dependent species, is not known to roost in buildings elsewhere; moreover there are no other known maternity colonies of this species in Sydney. The colony at the Park is therefore likely to be important to the continued conservation of the local population of this species.
Construction of new freshwater wetlands and terrestrial plantings across Sydney Olympic Park has increased the extent and diversity of foraging habitat for microbats over the past 10 years (though this was not a specific objective of these works).
Buildings with current or recent evidence of use by microbats, and buildings that may potentially be used by microbats have been identified, and protocols apply to use and management of these buildings.
Bat roost boxes were installed in some parts of the Park in 2003 to increase the available roosting habitat for microbats, but these do not appear to have been used by microbats to date.
The White-striped Free-tailed bat colony is being studied as part of a long-term research project.
Bat Survey at Sydney Olympic Park 2001-2002
To download the document 'Bat survey 2005-2006' and other surveys at Sydney Olympic Park, visit Environment Reports for more information.
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With glossy black fur on the head grading to brown on the lower back, Gould's Wattled Bat is one of the most regularly encountered bats in the Sydney area. They often roost within the roofs of buildings, sometimes for the birth and raising of young. Twins are normally born in October or November and are independent by 6 weeks. A previously used maternity roost is located in the roof of a building adjoining Newington Nature Reserve. A variety of flying insects are eaten by this bat including moths, beetles, bugs, cockroaches, crickets and ants. Preferred foraging areas include the edges of forest patches as well as in gaps in the canopy. |
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With a wingspan of nearly one metre and weight of up to one kilogram, the Grey-headed Flying-fox is a conspicuous bat. They are often noticed at night by their raucous social calls as they compete for food. In urban settings, this includes the fruits of Moreton Bay Figs, palms and other rainforest plants as well as the nectar of eucalypts, banksias, paperbarks and the leaves of mangroves. During the day they "hang out" in camps generally located in rainforest gullies or along rivers or creeks. At dusk they leave for feeding areas up to 40 kilometres from the camps. Numbers at the camps may vary from several hundred individuals up to many thousands. Grey-headed Flying-foxes feeding at Sydney Olympic Park may travel from camps located at the Sydney Royal Botanic Gardens, Gordon or Cabramatta. A single young born in September or October is fully furred and alert. The young are left in a group in the camp while females feed in surrounding areas. The Grey-headed Flying-fox is listed as vulnerable under the Threatened Species Conservation Act, 1995 and the Environment Protection and Biodiversity Conservation Act, 1999. While it appears to have suffered a severe decline throughout most of its range, it still occurs in reasonable numbers within the Sydney basin. |
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The distinctive long ears of the Lesser Long-eared Bat assist it to locate prey. It is different to other microbats within Sydney Olympic Park in that much of its prey is located using passive hearing, sight and smell, rather than solely by use of echolocation whilst in flight. It often hunts for insects found on or close to the ground such as beetles, cockroaches and ants, but will also hunt for insects in flight such as moths. The species occurs throughout the year within the Eucalypt and Casuarina forests of the Newington Nature Reserve, and by day it often roosts under the bark of live and dead trees. Single young or twins are born in spring. Breeding sites include the roof and wall cavities of buildings located near the Newington Nature Reserve. The Lesser Long-eared Bat is not considered threatened on a State or National level, but its numbers are declining within the Sydney basin. This population is the closest known breeding colony to the Sydney CBD, and was estimated at less than 100 individuals in 2001. |
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Another bat that regularly uses buildings for daytime shelter, the Little Freetail Bat has dark grey/brown fur, and wrinkled lips. As the name indicates, its tail protrudes from the tail membrane for much of its length. Confusion currently exists regarding the appropriate scientific name for this bat that extends along the east coast from Cape York to southern Victoria. This species feeds on bugs, ants, beetles and moths that it catches in flight. Within the Park, it has been recorded feeding around wetlands, saltmarsh as well as around artificial lights. A probable maternity roost of this bat is located in a building adjacent to Newington Nature Reserve and is shared with the White-striped Free-tailed Bat. A single young is born in late November. |
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A relatively plain bat, the Eastern Broad-nosed Bat is a warmish brown on the head and back with slightly lighter fur on its chest. Roosts are located within tree hollows but this bat also regularly roosts within roof cavities of buildings in the Sydney basin. Roosts within buildings are often shared with other microbats including Gould's Wattled Bat and the Little Freetail Bat. The diet of this species is unknown but is likely to consist of flying insects. Bats of this species are often observed over waterbodies including rivers and streams. A single young is born in late November or early December. |
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With thick, glossy auburn fur, vivid white stripes along the sides of the belly, wrinkled lips and large ears the White-striped Free-tailed Bat is a striking animal. It's long narrow wings are adapted for fast direct flight as it forages for large insects including moths, beetles and grasshoppers above the forest canopy and over wetlands. Unlike most of the other microbats from Sydney Olympic Park, its echolocation calls are audible to humans. These calls, a loud "chink.......chink......chink" carry for at least several hundred metres. It normally roosts during the day within hollows in trees but has also been recorded roosting within buildings. A maternity roost has been recorded within a building adjoining the Newington Nature Reserve, and is the only breeding colony of this species known from the Sydney area. It is being studied as part of a long-term research project. |
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Until its detection at the Park in 2002, the Little Bent-wing Bat wasn't known to occur south of the Hawkesbury River. This bat was recorded at Bicentennial Park during autumn 2002 from its distinctive echolocation calls. Like the Large Bent-wing Bat, with which it often shares roosts, females migrate long distances in spring to maternity roosts. Only one maternity roost, located near Kempsey, is known within New South Wales. At this site females rely on greater numbers of the Large Bent-wing Bat to elevate the temperature and humidity within the cave. During the winter months the bats disperse to roost in smaller groups. The Little Bent-wing Bat is listed as vulnerable under state legislation on Schedule 2 of the Threatened Species Conservation Act 1995. |
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The Large Bent-wing Bat is only present within Sydney Olympic Park from March until September. It forages for flying insects, particularly moths, above and around the canopy of forested areas and also feeds around artificial lights where insects are concentrated. During spring, females migrate several hundred kilometres from Sydney to maternity roosts, which are normally located in limestone cave systems. Up to one hundred thousand females may gather to bear a single young each, and, in the process, their large numbers elevate the temperature and humidity within the cave, thus speeding up the development of the young. During the winter months the bats disperse to roost in smaller groups in scattered localities including Sydney Olympic Park. It does not appear to roost within the parklands during the day, but has been recorded roosting in stormwater drains in the surrounding suburbs. The Large Bent-wing Bat is listed as vulnerable under state legislation on Schedule 2 of the Threatened Species Conservation Act 1995. |
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