Rhinonicteris aurantiaorange leaf-nosed bat
Geographic Range
This species is found in northern and northwestern Australia.
- Biogeographic Regions
- australian
- arctic ocean
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.
- Terrestrial Biomes
- forest
- rainforest
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).
- Other Physical Features
- endothermic
- bilateral symmetry
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.
- Key Behaviors
- motile
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.
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- IUCN Red List
-
Least Concern
More information
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.
- 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.