Biodiversity

Species Profile and Threats Database


For information to assist proponents in referral, environmental assessments and compliance issues, refer to the Policy Statements and Guidelines (where available), the Conservation Advice (where available) or the Listing Advice (where available).
 
In addition, proponents and land managers should refer to the Recovery Plan (where available) or the Conservation Advice (where available) for recovery, mitigation and conservation information.

EPBC Act Listing Status Listed as Extinct
Adopted/Made Recovery Plans
Other EPBC Act Plans Recovery plan for Stream Frogs of South-east Queensland 2001–2005 (Hines, H.B. & South-east Queensland Threatened Frogs Recovery Team (SEQTFRT), 2002) [Recovery Plan].
 
Threat Abatement Plan for Predation, Habitat Degradation, Competition and Disease Transmission by Feral Pigs (Australian Government Department of the Environment and Heritage (AGDEH), 2005p) [Threat Abatement Plan].
 
Threat Abatement Plan for infection of amphibians with chytrid fungus resulting in chytridiomycosis (Commonwealth Department of the Environment and Heritage (DEH), 2006o) [Threat Abatement Plan].
 
Federal Register of
    Legislative Instruments
Declaration under s178, s181, and s183 of the Environment Protection and Biodiversity Conservation Act 1999 - List of threatened species, List of threatened ecological communities and List of threatening processes (Commonwealth of Australia, 2000) [Legislative Instrument].
 
State Listing Status
QLD: Listed as Endangered (Nature Conservation Act 1992 (Queensland): May 2014 list)
Non-statutory Listing Status
IUCN: Listed as Extinct (Global Status: IUCN Red List of Threatened Species: 2013.1 list)
Scientific name Rheobatrachus silus [1909]
Family Myobatrachidae:Anura:Amphibia:Chordata:Animalia
Species author Liem,1973
Infraspecies author  
Reference  
Distribution map Species Distribution Map not available for this taxon.
Illustrations Google Images

Scientific name: Rheobatrachus silus

Common name: Southern Gastric-brooding Frog

The Southern Gastric-brooding Frog was a moderately large, aquatic frog, with males 30–44 mm in size and females 41–54 mm (Ingram 1983; Tyler & Davies 1983a). The dorsal surface was brown, or olive-brown to almost black, usually with obscure darker blotches on the back. A dark streak ran from the eye to base of the forelimb. There were darker cross-bars on the limbs, and pale and dark blotches and variegations on the digits and webbing. The ventral surface was white or cream with yellow markings on the limbs. The skin was finely granular above and smooth below (Cogger 2000; Liem 1973; Tyler & Davies 1983a).

The Southern Gastric-brooding Frog's snout was blunt and rounded, with the eyes and nostrils directed upwards. The species' eyes were large and prominent, located close together and close to the front of the head. The tongue was largely adherent to the floor of mouth. The typanum (ear cavity) was hidden. The fingers lacked webbing, while the toes were fully webbed. Digits had small discs (Cogger 2000; Liem 1973; Tyler & Davies 1983a).

The Southern Gastric-brooding Frog has not been recorded in the wild since 1981 (Richards et al. 1993).

The Southern Gastric-brooding Frog was restricted to elevations between 400–800 m in the Blackall and Conondale Ranges in south-east Queensland (Sunshine Coast Hinterland) (Hines et al. 1999). Distributions occurred between Coonoon Gibber Creek and Kilcoy Creek (Hines et al. 1999) in streams in the catchments of the Mary River, Stanley River and Mooloolah River (Ingram 1983). The species was thought to have been first discovered in 1972 (Liem 1973) but Ingram (1991) reported a specimen collected in 1914 from the Blackall Range.

The geographic distribution of the Southern Gastric-brooding Frog was less than 1000 km² (Hines et al. 1999).

The Southern Gastric-brooding Frog has been collected from Kondalilla National Park, Conondale National Park, Sunday Creek, State Forest 311, Kenilworth State Forest and from private land adjacent to these areas (Hines et al. 1999).

Since a review of the species by Ingram and McDonald (1993), the following surveys and monitoring were undertaken (Hines et al. 1999; Hines & SEQTFRT 2002; Ingram 1983):

  • Regular monitoring at Booloumba Creek, Bundaroo Creek, Peters Creek and East Kilcoy Creek in the Conondale Range and at Picnic Creek on the Blackall Range.
  • In 1995, an intensive "frog search" of Conondale Ranges.
  • In 1997, a "frog search" of the headwaters of Kilcoy Creek, North Booloumba Creek and Bundoomba Creek, Conondale Range.
  • Since 1996, systematic surveys of many streams in Conondale Range and Blackall Range. Some sections of streams were visited on many occasions over a range of weather conditions. Poorly surveyed streams in the Upper Stanley River were targeted.

The Southern Gastric-brooding Frog underwent a decline in winter 1979 (Czechura & Ingram 1990; Tyler & Davies 1985) and the last sighting occurred September 1981 in the Blackall Range (Richards et al. 1993). Ingram (1983) studied a population of the species in the headwaters of Booloumba Creek, Conondale Range, and estimated that approximately 78 were present in 1976. No other estimates of population size are available for the species.

The last known specimen died in captivity in November 1983 (Tyler & Davies 1985). Searches have continued unsuccessfully, most recently in November 1999 (Ingram & McDonald 1993). Other frog species that have declined in south-east Queensland since the 1970s include the Southern Day Frog (Taudactylus diurnus: extinct), Fleay's Frog (Mixophyes fleayi: endangered) and the Southern Barred Frog (Mixophyes iteratus: endangered) (Ingram & McDonald 1993).

Habitat for the Southern Gastric-brooding Frog was permanent to ephemeral freshwater streams over 300 m in altitude, in rainforest and wet sclerophyll forest communities of Blackall Range, Conondale Range and D'Aguilar Range (Hines & SEQTFRT 2002).

The Southern Gastric-brooding Frog was an aquatic species and was never located more than four metres from water. This species was restricted to rocky perennial streams, soaks and pools in rainforest and tall open forest with a closed understorey. It preferred rock pools and backwaters with leaf litter and rocks in which to shelter (Ingram 1983).

The Southern Gastric-brooding Frog was most active during the warmer months (September–April), with abundance decreasing as conditions become drier in winter (Ingram 1983). It is not known where these individuals went during this period, but it is believed they hibernated in deep crevices in the rocks (Ingram 1983; Liem 1973). Individuals were active night or day, particularly after rain. They established home ranges in and around suitable pools, spending extended periods partly submerged and immobile. When heavy rain fell, the males moved away from the water and called from sheltered hollows or crevices above the pools (Ingram 1983).

Breeding activity for the Southern Gastric-brooding Frog occured between October and December and appeared to be dependent on summer rains (Ingram 1983). The species featured a unique reproductive mode in which eggs or early larvae were swallowed by the female and completed their development in the stomach (Tyler & Carter 1982). Hormones produced by the young inhibited the digestive secretions of the stomach and rendered the upper intestine inactive (Tyler et al. 1983).

The larvae relied on yolk reserves throughout development. Up to 25 young were brooded in each event and emerged from the mother's mouth as fully formed metamorphs at about six to seven weeks. The digestive tract returned to its normal state and the female recommenced feeding within four days of releasing the young (Tyler & Davies 1983b).

The brooding periods from two individuals of 36 and 43 days suggest that the duration was such that females were unlikely to breed twice in one season (Ingram 1983).

The species' call was a loud staccato, consisting of 30–34 pulses repeated in a long series. It sounded like "eeeehm eeeehm" with an upward inflection (Tyler & Davies 1983a).

The Southern Gastric-brooding Frog was observed to forage and take insects from both land and water (Ingram 1983). In an aquarium situation Lepidoptera, Diptera and Neuroptera were eaten (Liem 1973).

The Southern Gastric-brooding Frog was an aquatic species that was never recorded more than four metres from water (Ingram 1983). Males, females and juveniles appeared to have limited home ranges, although juveniles and gravid females were particularly mobile (females carrying young tended to be sedentary). Only two juveniles out of ten were found to have moved more than three metres between observations. Juveniles were mobile in the sense that they would move to newly created pools, but once stationed there they usually remained in that area. During a breeding season, the home range of females and males was estimated to be 0–3.4 m (n=4) and 0.6–2 m (n=10) respectively.

The following distances moved along a stream by seven individuals, between seasons (i.e. over a period of one year), were recorded: four females moved 1.8–46 m, and three males moved 0.9–53 m. Only three individuals moved more than 5.5 m (46, 46 and 53 m) and it would appear that they remained within the same pool or group of pools throughout the breeding season, only moving away during periods of high flow or flooding (Ingram 1983). Non-breeding winter habitat is unknown (Ingram 1983).

The Southern Gastric-brooding Frog could be distinguished from the Northern Gastric-brooding Frog (Rheobatrachus vitellinus) by its distribution, colour pattern and mottled webbing (Cogger 2000; Liem 1973; Tyler & Davies 1983a).

The reason(s) for the decline of the Southern Gastric-brooding Frog remains unknown (Tyler & Davies 1985). Populations were present in logged catchments in 1972–1979. Although the species persisted in the streams during these activities, the effects of timber harvesting on this aquatic species were never investigated. Its habitat is currently threatened by feral Pigs (Sus scrofa), invasion of weeds (especially Mistflower (Ageratina riparia)), and altered flow and water quality due to upstream disturbances (Hines et al. 1999).

Recent studies of amphibian disease have identified a chytrid fungus (Batrachochytrium dendrobatidis) as a cause of frog mortality and as the cause of death of frogs collected during declines (Berger et al. 1998, 1999). The investigation of the role played by chytrid fungus in the decline of the Southern Gastric-brooding Frog is a focus of the species recovery program (Hines & SEQTFRT 2002).

Although the Southern Gastric-brooding Frog is presumed extinct, the species is included in the National Recovery Plan for Stream Frogs of South-east Queensland (2001-2005) (Hines & SEQTFRT 2002). Management actions for chytrid fungus are covered in the Threat abatement plan for infection of amphibians with chytrid fungus resulting in chytridiomycosis (AGDEH 2006o).

The following table lists known and perceived threats to this species. Threats are based on the International Union for Conservation of Nature and Natural Resources (IUCN) threat classification version 1.1.

Threat Class Threatening Species References
Agriculture and Aquaculture:Livestock Farming and Grazing:Habitat loss and modification due to clearance of native vegetation and pasture improvements The Impact of Global Warming on the Distribution of Threatened Vertebrates (ANZECC 1991) (Dexter, E.M., A.D. Chapman & J.R. Busby, 1995) [Report].
Biological Resource Use:Logging and Wood Harvesting:Habitat loss, modification and degradation due to timber harvesting Species threats data recorded on the SPRAT database between 1999-2002 (Department of Sustainability, Environment, Water, Population and Communities (DSEWPaC), 2012i) [Database].
Invasive and Other Problematic Species and Genes:Invasive Non-Native/Alien Species:Competition and/or habitat degradation Ageratina riparia (Mistflower, Mist Flower, Creeping Croftonweed, River Eupatorium, Spreading Mistflower) An assessment of frog declines in wet subtropical Australia. In: Campbell, A., ed. Declines and Disappearances of Australian Frogs. Page(s) 44-63. (Hines, H., M. Mahony & K. McDonald, 1999) [Book].
Invasive and Other Problematic Species and Genes:Invasive Non-Native/Alien Species:Grazing, tramping, competition and/or habitat degradation Sus scrofa (Pig) An assessment of frog declines in wet subtropical Australia. In: Campbell, A., ed. Declines and Disappearances of Australian Frogs. Page(s) 44-63. (Hines, H., M. Mahony & K. McDonald, 1999) [Book].
Invasive and Other Problematic Species and Genes:Invasive and Other Problematic Species and Genes:Presence of pathogens and resulting disease Recovery plan for Stream Frogs of South-east Queensland 2001–2005 (Hines, H.B. & South-east Queensland Threatened Frogs Recovery Team (SEQTFRT), 2002) [Recovery Plan].
Natural System Modifications:Dams and Water Management/Use:Alteration of hydrological regimes and water quality An assessment of frog declines in wet subtropical Australia. In: Campbell, A., ed. Declines and Disappearances of Australian Frogs. Page(s) 44-63. (Hines, H., M. Mahony & K. McDonald, 1999) [Book].
Uncategorised:Uncategorised:threats not specified Rheobatrachus silus in Species Profile and Threats (SPRAT) database (Department of the Environment and Heritage, 2006wr) [Internet].

Berger, L., R. Speare & A. Hyatt (1999). Chytrid fungi and amphibian declines: overview, implications and future directions. In: Campbell, A., ed. Declines and Disappearances of Australian Frogs. Page(s) 23-33. [Online]. Canberra: Environment Australia. Available from: http://www.environment.gov.au/biodiversity/threatened/publications/frogs.html.

Berger, L., R. Speare, P. Daszak, D.E. Green, A.A. Cunningham, C.L. Goggin, R. Slocombe, M.A. Ragan, A.D. Hyatt, K.R. McDonald, H.B. Hines, K.R. Lips, G. Marrantelli & H. Parkes (1998). Chytridiomycosis causes amphibian mortality associated with population declines in the rainforest of Australia and Central America. In: Proceedings of the National Academy of Science USA. 95:9031-9036.

Cogger, H.G. (2000). Reptiles and Amphibians of Australia - 6th edition. Sydney, NSW: Reed New Holland.

Commonwealth Department of the Environment and Heritage (DEH) (2006o). Threat Abatement Plan for infection of amphibians with chytrid fungus resulting in chytridiomycosis. [Online]. Available from: http://www.environment.gov.au/biodiversity/threatened/publications/tap/chytrid.html.

Czechura, G.V. & G. Ingram (1990). Taudactylus diurnus and the case of the disappearing frogs. Memoirs of the Queensland Museum. 29:361-365.

Hines, H., M. Mahony & K. McDonald (1999). An assessment of frog declines in wet subtropical Australia. In: Campbell, A., ed. Declines and Disappearances of Australian Frogs. Page(s) 44-63. [Online]. Canberra: Environment Australia. Available from: http://www.environment.gov.au/biodiversity/threatened/publications/frogs.html.

Hines, H.B. & South-east Queensland Threatened Frogs Recovery Team (SEQTFRT) (2002). Recovery plan for Stream Frogs of South-east Queensland 2001–2005. [Online]. Report to Environment Australia, Canberra. Brisbane, Queensland: Queensland Parks and Wildlife Service. Available from: http://www.environment.gov.au/biodiversity/threatened/publications/recovery/stream-frogs/index.html.

Ingram, G. (1983). Natural History. In: M.J. Tyler, ed. The Gastric Brooding Frog. Page(s) 16-35. London: Croom Helm.

Ingram, G.J. (1991). The earliest records of the extinct Platypus Frog. Memoirs of the Queensland Museum. 30:454.

Ingram, G.J. & K.R. McDonald (1993). An update on the decline of Queenslands frogs. In: Lunney, D. & D. Ayers, eds. Herpetology in Australia: a diverse discipline. Page(s) 297-303. Sydney, NSW: Royal Zoological Society of NSW.

Liem, D.S. (1973). A new genus of frog of the family Leptodactylidae from South-east Queensland, Australia. Memoirs of the Queensland Museum. 16:459-470.

Richards, S.J., K.R. McDonald & R.A. Alford (1993). Declines in populations of Australia's endemic tropical rainforest frogs. Pacific Conservation Biology. 1:66-77.

Tyler, M.J. & D.B. Carter (1982). Oral birth of the young of the gastric-brooding frog Rheobatrachus silus. Animal Behaviour. 29:280-282.

Tyler, M.J. & M. Davies (1983a). Larval development. In: Tyler, M.J., ed. The Gastric Brooding Frog. Page(s) 44-57. London: Croom Helm.

Tyler, M.J. & M. Davies (1983b). Superficial features. In: Tyler, M.J., ed. The Gastric Brooding Frog. Page(s) 5-15. London: Croom Helm.

Tyler, M.J. & M. Davies (1985). The gastric brooding frog. In: Grigg, G., R. Shine & H. Ehmann, eds. Biology of Australasian Frogs and Reptiles. Page(s) 469-470. Sydney: Royal Zoological Society of NSW.

Tyler, M.J., D.J.C. Shearman, R. Franco, P. O'Brien, R.F. Seamark & R. Kelly (1983). Inhabitaion of gastric acid secretion in the Gastric Brooding Frog, Rheobatrachus silus. Science. 220:609-610.

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This database is designed to provide statutory, biological and ecological information on species and ecological communities, migratory species, marine species, and species and species products subject to international trade and commercial use protected under the Environment Protection and Biodiversity Conservation Act 1999 (the EPBC Act). It has been compiled from a range of sources including listing advice, recovery plans, published literature and individual experts. While reasonable efforts have been made to ensure the accuracy of the information, no guarantee is given, nor responsibility taken, by the Commonwealth for its accuracy, currency or completeness. The Commonwealth does not accept any responsibility for any loss or damage that may be occasioned directly or indirectly through the use of, or reliance on, the information contained in this database. The information contained in this database does not necessarily represent the views of the Commonwealth. This database is not intended to be a complete source of information on the matters it deals with. Individuals and organisations should consider all the available information, including that available from other sources, in deciding whether there is a need to make a referral or apply for a permit or exemption under the EPBC Act.

Citation: Department of the Environment (2014). Rheobatrachus silus in Species Profile and Threats Database, Department of the Environment, Canberra. Available from: http://www.environment.gov.au/sprat. Accessed Fri, 11 Jul 2014 03:44:31 +1000.