By Justin Cooper
Geographic Range
Macroderma gigas or the Ghost Bat is found in Northern Australia where it has a scattered distribution. It is found north of 29°S in Western Australia, Northern Territories, and Queensland.
(Ride 1970, Strahan 1983)
Biogeographic Regions:
australian 
(native ).
Habitat
Ghost Bats have been recorded in both arid regions (Pilbara region) and rainforest areas (north Queensland). Macroderma gigas roost in caves, old mine tunnels and in deep cracks in rocks. They usually roost in colonies but, because many of their roosting sites are being destroyed, it is rare to find large colonies. Ghost Bats are distributed widely but patchily across the northern half of Australia and are found in a variety of tropical habitats. Perhaps the species' most famous roosting and nesting sites, and largest colonies, are at Mount Etna caves, near Rockhampton in Queensland.
(Nowak 1991, Ride 1970, Strahan 1983)
These animals are found in the following types of habitat:
tropical ; terrestrial .
Terrestrial Biomes:
forest ; rainforest ; scrub forest .
Physical Description
(4.58 to 5.98 oz; avg. 5.28 oz)
(4.53 to 5.12 in; avg. 5.02 in)
(19.69 in)
SIZE: Head and body length is 10 to 13cm and forearm length is 10.2 to 11.2cm. Females are smaller than males.
WEIGHT: 130 to 170 grams.
Ghost Bats have a light grey, almost white, appearance and large long ears that are joined at the base. The head and body measure up to 130 mm with a wingspan of about 500 mm.
In the Pilbara district of Western Australia, Ghost Bats are of the pale 'ghostly' desert form with ashy-grey back and white under-parts. Juveniles are sooty-grey all over. In the northern part of their range, especially in Kimberley, Arnhem Land, and around Rockhampton in Queensland, adult Ghost Bats are a dark sooty-grey.
(Nowak 1991, Ride 1970, Strahan 1983)
Some key physical features:
endothermic ; bilateral symmetry .
Reproduction
Mating takes place in July and August, births occur from September to November.
Little is known about mating in ghost bats.
Mating takes place in July and August. Gestation lasts about three months and females bear a single young between September and November. Sexual maturity is attained in the second year of life. (Nowak, 1991, Ride 1970, Strahan 1983)
Key reproductive features:
iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization (internal ); viviparous .
Mothers form nursery colonies separate from the males while the young are being weaned. While the young are still suckling, they are left in the roost while the females go out to hunt. Juveniles then hunt with their mothers until they become completely independent. Young begin flying at 7 weeks and become weaned by the March following their birth. (Ride 1970, Strahan 1983)
Parental investment:
altricial ; female parental care .
Lifespan/Longevity
Information on lifespan in this species is lacking.
Behavior
Macroderma gigas are secretive and, being exclusively cave-dwelling, are so unobtrusive that human residents, even miners who enter the tunnels in which they occur, will claim to know of the presence of other bats but not M. gigas.
These bats roost alone or in small groups, though larger colonies occur seasonally. Sexes become largely segregated to different colonies during the birthing season and before young are weaned.
(Nowak, 1991, Ride 1970)
Food Habits
Macroderma gigas is Australia's only carnivorous bat, eating large insects, reptiles, frogs, birds, small mammals, and sometimes other bat species. Much of this prey is captured on the ground. Ghost Bats drop on mammals from above, enveloping them with their flight membranes, and kill them with bites about the head and neck. They eat large amounts of food including flesh, bones, teeth, fur, small feathers, and the chitinous exoskeletons of insects. Ghost Bats appear to need this roughage in their diet because if they are fed on boneless meat in captivity they soon become distressed and fouled with loose excreta.
(Ride 1970)
Primary Diet:
carnivore (eats terrestrial vertebrates, insectivore ).
Animal Foods:
birds; mammals; amphibians; reptiles; insects.
Predation
Ghost bats have few natural predators, though larger owls may take them at night and young may fall prey to roost predators, such as snakes. Medium-sized owls compete for insects and small mammals.
(Nowak 1991)
Ecosystem Roles
Ghost bats are important predators of small mammals, birds, and reptiles in the areas in which they live.
Economic Importance for Humans: Negative
There are no significant negative effects of ghost bats.
Economic Importance for Humans: Positive
Ghost bats are important in the control of rodents, especially introduced house mice, and other small mammals. They also produce guano, which can be used as a fertilizer.
Ways that people benefit from these animals:
produces fertilizer; controls pest population.
Conservation Status
IUCN Red List: [link]:
Vulnerable.
US Migratory Bird Act: [link]:
No special status.
US Federal List: [link]:
No special status.
CITES: [link]:
No special status.
Ghost Bats are sensitive to disturbance. Human intruders to a cave colony may cause the group to become nervous and leave. Many roost caves have been destroyed or are threatened by mining activity. Disturbance and loss of roosting sites due to mining, tourism and internal dereliction of mines through aging of timber supports are known threats. In recent times population declines could be attributable to competition for prey with feral cats, and prey lost through habitat modification by fire and livestock
Ghost Bats are protected by national legislation in Australia.
(UNEP 2001)
For More Information
Find Macroderma gigas information at
Contributors
Justin Cooper (author), University of Wisconsin-Stevens Point.
Chris Yahnke (editor), University of Wisconsin Stevens Point.
