White-striped free-tailed bat

Last updated

White-striped free-tailed bat
A. australis.jpg
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Chiroptera
Family: Molossidae
Genus: Austronomus
Species:
A. australis
Binomial name
Austronomus australis
(Gray, 1838)
Synonyms
  • Molossus australisGray, 1838 [2]
  • Tadarida australis (Gray, 1838)
  • Nyctinomus australis (Gray, 1838)

The white-striped free-tailed bat (Austronomus australis) is a species of bat in the family Molossidae. Its echolocation calls are audible to humans, which is a characteristic found in only a few microbat species. [3] The species was formerly classified as Tadarida australis. [4]

Contents

Taxonomy

The first description of the species was published in 1838 by John Edward Gray, in a review of material at the British Museum of Natural History. The author noted the source of the specimen, a skin and skull, as New South Wales and placed it with the genus Molossus . When providing a description in Furred Animals of Australia, Ellis Troughton suggested that the specimen examined by Gray was obtained at Camden, a property owned by John Macarthur. Troughton first proposed the species be distinguished as a monotypic genus Austronomus , this arrangement was eventually resurrected when the taxon was separated from the previously accepted placement in the widespread genus Tadarida . [5] [6]

Koopman [7] included these species in Tadarida with T. kuboriensis as a subspecies of T. australis. Gregorin and Cirranello found that these two species formed a clade distinct from other Tadarida, differing in eight morphological characters. [8] The most significant of these is a keel present between the nostrils, a synapomorphy combining this clade. [8] Likewise, T. kuboriensis and T. australis lack hair on the tragus and do not have thornlike hairs on the face. The presence of hair on the tragus is a synapomorphy for non-Australasian Tadarida. [8] Based on these results, Gregorin and Cirranello (2016) recommended recognition of Austronomus Troughton 1943 based on the type species Molossus australis Gray, 1834. [8]

Description

The white-striped free-tailed bat is robust in build [6] and the largest of the eleven Australian Molossids. The colour of the pelage is a deep chocolate brown, with well defined white stripes beneath the wing; occasional patches of white may appear at the upper ventral side. Individuals have a mass of 33 to 41 grams, and average of 37 g, and a head and body length of 85 to 100 millimetres. [6] The free tail extends 40 to 55 mm from the body and can be folded during high speed flight to reduce drag. [9] [10] The forearm length range is 57-63 mm. [6] It has a condylobasal length of 23–24 mm. The skull is dorso-ventrally flattened. The baculum is divided into three lobes. [11]

The White-striped Free-tail Bat is named for the distinctive stripes of white fur on the underside where the wings meet the body. White-striped Free-tail Bat (Tadarida australis).jpg
The White-striped Free-tail Bat is named for the distinctive stripes of white fur on the underside where the wings meet the body.

This species has a wingtip shaped similarly to the crescent form found on fast-flying birds and on the caudal fins of fast-swimming fish. [12] These tips have leading edges that curve around to chordwise orientation and have trailing edges with aft-sweep or zero-sweep over the outer half of the tip. This bat's wings are considered as having low camber sections with faired humerus and radius bones, typical leading-edge flaps and surface disjunctions and protuberances. This allows this interceptor species to optimise for least drag generation at the expense of maximum lift ability at high speeds. [13] The white-striped free-tailed bat can reach speeds of up to 17 m/s. [10]

The large, forward pointed ears are 20 to 25 mm in length and assist in their aerodynamic lift. [10] The ears are exceptionally broad and noticeably ribbed. [6] A short hairless tragus is present and also points forward. The inner margins of the ears touch, but are not joined where they meet on the head. [8] The upper lip is deeply wrinkled, and this species have single incisor teeth on each of the frontal cranial bones of the upper jaw. Both sexes have a throat pouch. [9] The colour of the skin is very dark, blackish, with a slight pink hue. [6] Fur colour varies with dark brown dorsally and lighter ventrally. A distinctive pattern of white fur on each side of the body progresses from the front to the back where the wings fold against the body, giving this species its common name, white-striped free-tailed bat. This species displays sexual dimorphism with the male being larger.

Echolocation

The white-striped free-tailed bat typical call has been recorded between 10-15 kHz. [10] The species emits one to two calls per second and unlike the ultrasonic signals of most microchiropterans these are audible to humans. The sounds is described as "pink-pink-pink" or a "metallic ting-ting-ting". [14] [6] Research by Herr and Klomp into the white-striped free-tailed bat's calls showed that vocalisation changed at different stages of flight. [15] In the initial stages of flight, after release, this species used steep frequency modulated pulse, from 27 kHz to 13 kHz, changing to a low frequency modulated pulse when flying above a canopy. Once there the call structure changes to the more typical white-striped free-tailed bat call with a constant frequency with a divergence between maximum and minimum frequency of 5 kHz. All echolocating bats use a terminal phase buzz call to locate, close in and capture their prey. [16]

Distribution and habitat

An endemic species to Australia, the white-striped free-tailed bat is widespread and common. They are seasonally migratory but not recorded in the northern third of the continent nor previously known on the southern island of Tasmania. [6] [9] However, surveys conducted in Tasmania between 2009 and 2013 indicated the species is present and maybe a periodic visitor or vagrant in Tasmania. [17] In Western Australia this species is restricted south of the 20°S latitude during the breeding season, the austral spring and summer, then extending north in the winter. [18] [19] This species can be found in most habitats from closed forest to open flood plain, and occurs in urban areas, in regions across temperate and subtropical Australia.

Roosts

In the Greater Brisbane Region of South East Queensland the white-striped free-tail bat uses over-mature to dead eucalypt species with large tree diameters (>89 cm) as roost habitats. [20] These trees have developed large trunk cavities, often extending throughout the trunk and major branches. [20] The bats access these cavities through multiple unobstructed branches and/or trunk hollows. [20] This strategy also allows the bats a direct flight path when leaving the roost cavities which may result in energy savings for the bats and reduce the exposure to predators. [21] [22]

Although single bats spend most of their daytime in separate day-roosts, they spent an average of one day in every eleven within the communal roost. [20] The bats also visited the communal roost for periods of time during their nocturnal activity, and some individuals were recorded twice as often frequenting the communal roost during the night compared with the day. [23]

This bat species is a highly colonial tree-dweller, so that large internal hallows are an important feature in selecting suitable maternity roost sites as population numbers increase during parturition. Therefore, the quality and size of roost space is more important than the selection of a particular species of tree in maternity roost choice. [20] [24]

Biology and ecology

The white-striped free-tailed bat is a specialized high-altitude, fast-flying interceptor insectivore. [25] [26] Their diet consists principally of moths, beetles and bugs. [10]

In South East Queensland, white-striped free-tailed bats demonstrated a significant preference for foraging above flood plain habitat and does not prefer to feed above remnant forests. [27] In northern Australian urban areas, foraging individuals preferred and were in greater concentrations over grassland with few trees, such as golf courses, than over riparian areas, new urban developments, and suburbs that had been established for between 20–50 years. [28] White-striped free-tailed bats once they emerge from their roosts fly rapidly and directly to their foraging area, with individual bats flying up to 20 kilometres (12 mi) to reach their feeding areas. However, some populations have a more localised foraging area. In the greater Brisbane area, foraging areas are usually within 2.5 km (1.6 mi) of day roost and 6.2 km (3.9 mi) of communal roosts. [27] On arrival they reduce their commuting flight speed to a lower sustainable flight speed that allows them to hunt in the foraging area for some hours. [27] [11] The species is agile on hard ground or other firm surfaces. [6] Some researchers[ who? ] report that the bat will also scurry around on the ground chasing ground-dwelling insects such as beetles, bugs, grasshoppers and ants. They are able to do this by folding their wings away neatly so that their forearms are free, retracting their tail membrane and scampering around on their thumbs and hind feet.

Males do not have the ability to store sperm in their vesicular follicles during the winter period, therefore breeding commences late in August. Females give birth to one young between mid-December and mid-January, which indicates a gestation period of about 14 weeks. [29]

Related Research Articles

<span class="mw-page-title-main">Vespertilionidae</span> Family of microbats

Vespertilionidae is a family of microbats, of the order Chiroptera, flying, insect-eating mammals variously described as the common, vesper, or simple nosed bats. The vespertilionid family is the most diverse and widely distributed of bat families, specialised in many forms to occupy a range of habitats and ecological circumstances, and it is frequently observed or the subject of research. The facial features of the species are often simple, as they mainly rely on vocally emitted echolocation. The tails of the species are enclosed by the lower flight membranes between the legs. Over 300 species are distributed all over the world, on every continent except Antarctica. It owes its name to the genus Vespertilio, which takes its name from a word for bat, vespertilio, derived from the Latin term vesper meaning 'evening'; they are termed "evening bats" and were once referred to as "evening birds".

<span class="mw-page-title-main">Free-tailed bat</span> Family of bats

The Molossidae, or free-tailed bats, are a family of bats within the order Chiroptera. The Molossidae is the fourth-largest family of bats, containing about 110 species as of 2012. They are generally quite robust, and consist of many strong-flying forms with relatively long and narrow wings with wrinkled lips shared through their genus. Their strong flying form allows them to fly 60 miles per hour using tail winds and at altitudes over 10,000 feet. This makes them unique among bats, as they are the only bat family that withstands the elevation. They are widespread, being found on every continent except Antarctica. They are typically found in caves, abandoned mines, or tunnels.

<span class="mw-page-title-main">Mexican free-tailed bat</span> Species of bat native to the Americas

The Mexican free-tailed bat or Brazilian free-tailed bat is a medium-sized bat native to North, Central, and South America and the Caribbean, so named because its tail can be almost half its total length and is not attached to its uropatagium. It has been claimed to have the fastest horizontal speed of any animal, reaching top ground speeds over 99 mph (160 km/h). It also flies the highest among bats, at altitudes around 3,300 m (10,800 ft).

<span class="mw-page-title-main">Common blossom bat</span> Species of bat

The common blossom bat also known as the southern blossom bat or Queensland blossom bat, is a megabat in the family Pteropodidae. The common blossom bat feeds mostly on nectar and pollen rather than fruit. It is one of eight Pteropodidae species on mainland Australia. It is one of the smallest of all nectarivorous megabats.

<i>Micronomus</i> Species of bat

Micronomus norfolkensis is a species of molossid bat, a family of flying mammals. The bat is endemic to Australia, where it occurs from southeastern Queensland to eastern New South Wales. They are the sole species of genus Micronomus and referred to by variations on east-coast free-tailed bat.

<i>Ozimops planiceps</i> Species of bat

Ozimops planiceps is a small bat in the family Molossidae, native to Australia and Indonesia.

<span class="mw-page-title-main">Inland broad-nosed bat</span> Species of bat

The inland broad-nosed bat is a species of vesper bat. They are endemic to Australia and widespread throughout the inland, especially in arid and semi-arid regions. This insectivorous microbat, measuring 12 centimetres (4.7 in) in length, roosts in tree hollows during the day and forages over woodland and water at night.

The Solomons mastiff bat is a species of bat in the family Molossidae. It is endemic to the Solomon Islands.

<span class="mw-page-title-main">Mongalla free-tailed bat</span> Species of bat

The Mongalla free-tailed bat is a species of bat in the family Molossidae. It is found in Burkina Faso, Cameroon, Democratic Republic of the Congo, Ivory Coast, Ghana, Kenya, Mali, Sudan, and Uganda. Its natural habitats are dry savanna, moist savanna, and subtropical or tropical seasonally wet or flooded lowland grassland.

<span class="mw-page-title-main">Pocketed free-tailed bat</span> Species of bat

The pocketed free-tailed bat is a species of bat in the family Molossidae found in Mexico and in Arizona, California, New Mexico, and Texas in the United States. They resemble the Brazilian free-tailed bat but differ morphologically. They are recognized as "least concern" by the IUCN and as "apparently secure" by Natureserve.

<span class="mw-page-title-main">Egyptian free-tailed bat</span> Species of bat

The Egyptian free-tailed bat, also known as Egyptian guano bat or Egyptian nyctinome, is a species of bat in the family Molossidae.

<span class="mw-page-title-main">Blunt-eared bat</span> Species of bat

The blunt-eared bat or Peruvian crevice-dwelling bat is a species of bat in the family Molossidae. It is monotypic within the genus Tomopeas and subfamily Tomopeatinae. It is endemic to Peru, where it is considered critically endangered. It is threatened by habitat loss.

<span class="mw-page-title-main">Florida bonneted bat</span> Species of bat

The Florida bonneted bat or Florida mastiff bat is a species of bat in the genus Eumops, the bonneted bats or mastiff bats. Until recently, it was classified as a subspecies of Wagner's bonneted bat. It is endemic to southern Florida in the United States. This species has one of the smallest geographical distributions of any New World bat. It has been called "one of the most critically endangered mammal species in North America". It is protected under the Endangered Species Act.

<i>Setirostris</i> Genus of bats

Setirostris eleryi is a species of small insectivorous bat found in inland eastern Australia. It is the sole species of the molossid genus Setirostris, a name that refers to the coarse bristles on their faces. Earlier common names have referred to this unique feature, and the 'free-tail' that is a common feature of its microchiropteran family, the Molossidae; no single common name emerged during the taxonomic revisions that identified what was referred to as the bristle-faced freetail.

Ozimops ridei is a species of molossid bat found in eastern Australia.

Austronomus, known as Australasian free-tailed bats, is a molossid genus of microchiropterans. The two recognised species are the white-striped Austronomus australis, found in a wide distribution range across Australia, and the New Guinea species Austronomus kuboriensis.

<i>Eumops ferox</i> Species of bat

Eumops ferox, the fierce bonneted bat or the chestnut mastiff bat, is a species of free-tailed bat found in the Caribbean and Mexico. Until recently, it was synonymous with Wagner's bonneted bat.

Ozimops kitcheneri, the south-western free-tailed bat, is a species of molossid bat found in Southwest Australia. A small flying mammal, it forages in forests and woodlands for insects.

Ozimops is a genus of molossid bats found in Australia, Indonesia and Papua New Guinea.

Ozimops cobourgianus is a species of molossid bat, insectivorous flying mammals known as freetail bats, which are found in north and west coastal regions of Australia. First described in 1959, the group were later recognised as species Mormopterus cobourgianus and soon placed with a new genus. They are associated with mangrove habitat and roost in the hollows of those trees, and known to seek food there and in eucalypt or melaleuca woodland or other coastal habitat. A smaller bat of genus Ozimops, O. cobourgianus are around fifty millimetres long and weigh six to ten grams. Little is known of their habits.

References

  1. ↑ Pennay, M. (2020). "Austronomus australis". IUCN Red List of Threatened Species . 2020: e.T21313A22121905. doi: 10.2305/IUCN.UK.2020-3.RLTS.T21313A22121905.en . Retrieved 14 November 2021.
  2. ↑ Gray, J. E. (1839). "A Revision of the Genera of Bats (Vespertilionidæ), and the Description of some new Genera and Species". Magazine of Zoology and Botany. 2: 501–502.
  3. ↑ Regional Group, Burnett Mary (2017-06-10). "White-striped freetail bat". All About Bats. Retrieved 7 February 2018.
  4. ↑ McKenzie, N.; Pennay, M.; Richards, G. (2008). "Austronomus australis". IUCN Red List of Threatened Species . 2008: e.T21313A9269147. doi: 10.2305/IUCN.UK.2008.RLTS.T21313A9269147.en .
  5. ↑ "Species Austronomus australis (Gray, 1838)". Australian Faunal Directory . Australian Government.
  6. 1 2 3 4 5 6 7 8 9 Menkhorst, P.W.; Knight, F. (2011). A field guide to the mammals of Australia (3rd ed.). Melbourne: Oxford University Press. p. 154. ISBN   9780195573954.
  7. ↑ Koopman, K. F. (1982). "Bats from eastern Papua and the East Papuan islands". American Museum Novitates (2747).
  8. 1 2 3 4 5 Gregorin, Renato; Cirranello, Andrea (2016). "Phylogeny of Molossidae Gervais (Mammalia: Chiroptera) inferred by morphological data". Cladistics. 32 (1): 2–35. doi: 10.1111/cla.12117 . PMID   34732020. S2CID   84010894.
  9. 1 2 3 Strahan, R (1995). The Mammals of Australia: The National Photographic Index of Australian Wildlife. Reed Books. ISBN   978-0730104841.
  10. 1 2 3 4 5 Bullen, R; McKenzie, N. L (2001). "Bat airframe design: flight performance, stability and control in relation to foraging ecology". Australian Journal of Zoology. 49 (3): 235. doi:10.1071/ZO00037.
  11. 1 2 Clemens, W.; Richardson, B. J.; Baverstock, P. R. (1989). Fauna of Australia. Vol. 1B. Canberra: Australian Government Publishing Service. p. 17.
  12. ↑ Lazos, Barry S (2005). "Biologically Inspired Fixed-Wing Configuration Studies". Journal of Aircraft. 42 (5): 1089–1098. doi:10.2514/1.10496.
  13. ↑ Bullen, R. D; McKenzie, N. L (2007). "Bat wing airfoil and planform structures relating to aerodynamic cleanliness". Australian Journal of Zoology. 55 (4): 237. doi:10.1071/ZO07010.
  14. ↑ Powys, V. (2010). "Recording microchiropteran bats" (PDF). Journal of the Australian Wildlife Sound Recording Group Inc. 13 (1).
  15. ↑ Herr, A.; Klomp, N.I. (1997). Reference calls of the White-striped free-tailed bat, Nyctinomus australis (Report). Australian Bat Society Newsletter. pp. 16–19.
  16. ↑ Griffiths, Stephen R (2013). "Echolocating bats emit terminal phase buzz calls while drinking on the wing". Behavioural Processes. 98: 58–60. doi:10.1016/j.beproc.2013.05.007. PMID   23701945. S2CID   2383965.
  17. ↑ Cawthen, Lisa (2013). "White-striped freetail bat in Tasmania – resident, vagrant or climate change migrant?". Australian Mammalogy. 35 (2): 251. doi:10.1071/AM12052.
  18. ↑ Bullen, R. D; Dunlop, J. N (2012). "Assessment of habitat usage by bats in the rangelands of Western Australia: Comparison of echolocation call count and stable isotope analysis methods". The Rangeland Journal. 34 (3): 277. doi:10.1071/RJ12001.
  19. ↑ Bullen, R. D; McKenzie, N. L (2005). "Seasonal range variation of Tadarida australis (Chiroptera:Molossidae) in Western Australia: The impact of enthalpy". Australian Journal of Zoology. 53 (3): 145. doi:10.1071/ZO04080.
  20. 1 2 3 4 5 Rhodes, Monkia; Wardell-Johnson, Grant (April 2006). "Roost tree characteristics determine use by the white-striped freetail bat (Tadarida australis, Chiroptera: Molossidae) in suburban subtropical Brisbane, Australia". Austral Ecology. 31 (2): 228–239. Bibcode:2006AusEc..31..228R. doi:10.1111/j.1442-9993.2006.01587.x. ISSN   1442-9985.
  21. ↑ Vonhof, M. J. (1995). "Roost-site preferences of big brown bats (Eptesicus fuscus) and silver-haired bats (Lasionycteris noctivagans) in the Pend d'Oreille Valley in southern British Columbia". Bats and forest symposium. pp. 62–80.
  22. ↑ Fenton, M.B; Rautenbach, I.L; Smith, S.E; Swanepoel, C.M; Grosell, J; Van Jaarsveld, J (1994). "Raptors and bats: Threats and opportunities". Animal Behaviour. 48: 9–18. doi:10.1006/anbe.1994.1207. S2CID   54360964.
  23. ↑ Rhodes, Monika (2007). "Roost Fidelity and Fission–Fusion Dynamics of White-striped Free-tailed Bats (Tadarida australis)". Journal of Mammalogy. 88 (5): 1252–1260. doi: 10.1644/06-MAMM-A-374R1.1 .
  24. ↑ Sedgeley, Jane A; f.j. o'Donnell, Colin (1999). "Roost selection by the long-tailed bat, Chalinolobus tuberculatus, in temperate New Zealand rainforest and its implications for the conservation of bats in managed forests". Biological Conservation. 88 (2): 261. Bibcode:1999BCons..88..261S. doi: 10.1016/S0006-3207(98)00069-X .
  25. ↑ Churchill, S. (1998). Australian Bats. Sydney: New Holland Publishers.
  26. ↑ Vaughan, T. A (1966). "Morphology and Flight Characteristics of Molossid Bats". Journal of Mammalogy. 47 (2): 249–260. doi:10.2307/1378121. JSTOR   1378121.
  27. 1 2 3 Rhodes, Monika; Catterall, Carla (2008). "Spatial Foraging Behavior and Use of an Urban Landscape by a Fast-Flying Bat, the Molossid Tadarida australis". Journal of Mammalogy. 89: 34–42. doi: 10.1644/06-MAMM-A-393.1 .
  28. ↑ Hourigan, C. L; Johnson, C; Robson, S. K. A (2006). "The structure of a micro-bat community in relation to gradients of environmental variation in a tropical urban area". Urban Ecosystems. 9 (2): 67. Bibcode:2006UrbEc...9...67H. doi:10.1007/s11252-006-7902-4. S2CID   36171730.
  29. ↑ Kitchener, D. J.; Hudson, C. J. (1982). "Reproduction in the female white-striped mastiff bat, Tadarida australis (Gray)(Molossidae)". Australian Journal of Zoology. 30 (1): 1–14. doi:10.1071/ZO9820001.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.