Rhinonicteris aurantiaorange leaf-nosed bat

Geographic Range

This species is found in northern and northwestern Australia.

Habitat

This species is very selective in choosing hot, humid roosting sites. Roosts have been reported to be 30-32 C with 90-100% relative humidity. Golden horseshoe bats forage in open woodlands near their roosting caves.

Physical Description

The golden horseshoe bat typically has bright orange pelage, but regional variants occur. The head and body length of this bat averages 50mm, with an average tail length of 25mm. The species is sexually dimorphic in size, with females weighing significantly less than males (females average 7.6g, whereas males average 8.4 g).

Reproduction

Little is known about the reproductive cycle of the golden horseshoe bat. The animal is thought to breed during the wet season, which in Northern Australia is from October through April.

  • Key Reproductive Features
  • gonochoric/gonochoristic/dioecious (sexes separate)
  • sexual

Behavior

Information on the social behavior of this species is scant. The golden horseshoe bat typically roosts in abandoned mine shafts and caves in colonies comprising several hundred individuals. Smaller colonies may roost in the hollows of eucalyptus trees. The largest reported colony comprized more than 11250 individuals. While roosting, individuals maintain a distance of 12-15 centimeters from conspecifics. Two species are known to cohabit with the golden horseshoe bat. Hipposideros ater, the dusky horeshoe bat,is the most common cohabitator, but Macroderma gigas, the ghost bat, and bent-winged bats have also been observed to occupy Rhinonicteris roosts.

Communication and Perception

Food Habits

The golden horseshoe bat is insectivorous. These animals emerge from their roosting sites 0.5 to1.5 hours after sunset. They forage for insect prey while flying one to three meters above the vegetation. Primary prey items of this species include moths and beetles, but shield bugs, parasitic wasps, ants and weevils are also eaten.

Economic Importance for Humans: Positive

May help to control the populations of harmful insects.

Conservation Status

There is insufficient knowledge of this species to accurately determine its status. Rhinonicteris aurantia is the only species in the genus, and it has a limited geographic distribution. Its status has been described as sparse. There is an annecdotal account of an attempt to preserve roosting habitat. One colony of about 5000 bats was heavily visited by tourists. Conservationists, fearing the fate of bats so frequently disturbed by humans, placed a mesh screen over the opening to the cave in order to keep tourists out while allowing the bats free access to and from the cave. Unfortunately, the plan did not work. The bat population decreased drastically after the mesh screen was erected. It has since been removed, and the bat colony has stabilized at about 2000 individuals.

Contributors

Nancy Shefferly (author), Animal Diversity Web.

Glossary

Arctic Ocean

the body of water between Europe, Asia, and North America which occurs mostly north of the Arctic circle.

Australian

Living in Australia, New Zealand, Tasmania, New Guinea and associated islands.

World Map

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

chemical

uses smells or other chemicals to communicate

endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

forest

forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

rainforest

rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Epiphytes and climbing plants are also abundant. Precipitation is typically not limiting, but may be somewhat seasonal.

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

tactile

uses touch to communicate

References

Churchill, S.K. 1991. Distribution, abundance and roost selection of the orange horseshoe bat, Rhinonycteris aurantia, a tropical cave-dweller. Wildlife research 18(3): 343-353.

Churchill, S.K. 1994. Diet, prey selection and foraging behaviorur of the orange horseshoe bat, Rhinonycteris aurantia. Wildlife research 21(2): 115-130.

Jolly, S. 1988. Five colonies of the orange horseshoe bat, Rhinonycteris aurantus (Chiroptera: Hipposideridae) in the Northern Territory. Australian Wildlife Research 15(1): 41-49.

Straham, R. ed. 1983. The Australian museum complete book of Australian mammals.