Australian Journal of Zoology Australian Journal of Zoology Society
Evolutionary, molecular and comparative zoology

Distribution, prevalence and persistence of mucormycosis in Tasmanian platypuses (Ornithorhynchus anatinus)

Nick Gust A D , Joshua Griffiths A , Michael Driessen A , Annie Philips A , Niall Stewart B and Dominic Geraghty C

A Department of Primary Industries, Parks, Water and Environment, GPO Box 44, Hobart, Tas. 7001, Australia.

B Menzies Research Institute, University of Tasmania, Hobart, Tas. 7000, Australia.

C School of Human Life Sciences, University of Tasmania, Locked Bag 1320, Launceston, Tas. 7250, Australia.

D Corresponding author. Email:

Australian Journal of Zoology 57(4) 245-254
Submitted: 3 April 2009  Accepted: 23 July 2009   Published: 26 October 2009


While the fungal disease mucormycosis has infected Tasmanian platypuses for nearly three decades, its impacts remain largely unknown. This study documents the spatial and temporal distribution of mucormycosis in Tasmanian platypuses as a baseline for assessing its impacts. Over 1800 platypus capture and observation records were collated and mapped, and indicate that between 1982 and 2007 mucormycosis-infected platypuses were present in at least 11, and potentially 22, of Tasmania’s 48 river catchments. During 2008–09, live-trapping surveys were undertaken to determine the spread, prevalence and persistence of the disease. Surveys of 75 rivers and creeks across 18 catchments captured 167 individuals, and an additional 12 platypuses were obtained from the public. Only seven of the 179 sampled animals were ulcerated with clinical signs of mucormycosis. All infected individuals were obtained from catchments with prior histories of disease, where platypuses have persisted despite mucormycosis being present for up to 20 years. Detection probabilities were calculated to estimate the probability that the other surveyed catchments are currently disease free. Detection probabilities were generally high (>0.75) per catchment, indicating that sampling effort was adequate to reliably detect diseased animals at historically reported prevalence (which averaged 0.295 from surveys undertaken between 1994 and 2000). Mean disease prevalence in affected catchments sampled during the present study declined to 0.071. This significant four-fold reduction in prevalence makes disease detection more challenging and increased sample sizes are required to confidently assert that some catchments are currently disease free. Reduced disease prevalence suggests that mucormycosis is exerting less impact on Tasmanian platypuses now than it was in the mid to late 1990s; however, the individual consequences of infection are poorly understood and require further investigation.


Connolly J. H. Obendorf D. L. Whittington R. J. Muir D. B. 1998 Causes of morbidity and mortality in platypus (Ornithorhynchus anatinus) from Tasmania, with particular reference to Mucor amphibiorum infection. Australian Mammalogy 20 177 187

Connolly J. H. Obendorf D. L. Whittington R. J. 1999 Haematological, serum biochemical and serological features of platypuses with and without mycotic granulomatous dermatitis. Australian Veterinary Journal 77 809 813

Connolly J. H. Canfield P. Obendorf D. L. 2000 Gross, histological and immunohistochemical features of mucormycosis in the platypus. Journal of Comparative Pathology 123 36 46 doi:10.1053/jcpa.2000.0384

Dohoo I. , Martin W. , and Stryhn H. (2003). ‘Veterinary Epidemiologic Research.’ (AVC Inc.: Charlottetown, Canada.)

Frank W. (1975). Mycotic infections in amphibians and reptiles. In ‘Proceedings of the 3rd International Wildlife Disease Conference’. (Ed. L. A. Page.) pp. 73–88.

Grant T. Carrick F. 1974 Capture and marking of the platypus, Ornithorhynchus anatinus in the wild. Australian Zoologist 18 133 135

Grant T. Carrick F. 1978 Some aspects of the ecology of the platypus (Ornithorhynchus anatinus) in the Upper Shoalhaven River, NSW. Australian Journal of Zoology 20 181 199

Grant T. R. Temple-Smith P. D. 2003 Conservation of the platypus, Ornithorhynchus anatinus: threats and challenges. Aquatic Ecosystem Health & Management 6 5 18

Grant T. Whittington R. W. 1991 The use of freeze-branding and implanted transponder tags as a permanent marking method for platypus Ornithorhynchus anatinus. Australian Mammalogy 14 147 150

Gust N. Griffiths J. 2009 Platypus mucormycosis and its conservation implications. Australasian Mycologist 28 1 8

Hayes K. Cannon R. Neil K. Inglis G. 2005 Sensitivity and cost considerations for the detection and eradication of marine pests in ports. Marine Pollution Bulletin 50 823 834

Munday B. Peel B. F. 1983 Severe ulcerative dermatitis in platypus (Ornithoryhchus anatinus). Journal of Wildlife Diseases 19 363 365

Munday B. L. Whittington R. J. Stewart N. J. 1998 Disease conditions and subclinical infections in the platypus (Ornithorhynchus anatinus). Transactions of the Royal Society of London. Series B 353 1093 1099

Murray K. A. Skerratt L. F. Speare R. McCallum H. 2009 Impact and dynamics of disease in species threatened by the amphibian chytrid fungus Batrachochytrium dendrobatidis. Conservation Biology 23 1242 1252

Obendorf D. L. Peel B. F. Munday B. L. 1993 Mucor amphibiorum infection in platypus (Ornithorhynchus anatinus) from Tasmania. Journal of Wildlife Diseases 29 485 487

Speare R. Thomas A. O’Shea P. Shipton W. 1994 Mucor amphibiorum in the toad (Bufo marinus) in Australia. Journal of Wildlife Diseases 30 399 407

Stewart N. J. (2001). The epidemiology of ulcerative mycosis of the platypus (Ornithorynchus anatinus). Ph.D. Thesis. University of Tasmania, Hobart.

Stewart N. J. Munday B. L. 2005 Possible differences in pathogenicity between cane toad-, frog- and platypus-derived isolates of Mucor amphibiorum, and a platypus-derived isolate of Mucor circinelloides. Medical Mycology 43 127 132

Venette R. Moon R. Hutchinson W. 2002 Strategies and statistics of sampling for rare individuals. Annual Review of Entomology 47 143 174 doi:10.1146/annurev.ento.47.091201.145147

Whittington R. J. (1992). The role of infectious diseases in the population biology of monotremes. In ‘Platypus and Echidnas’. (Ed. M. L. Augee.) pp. 285–292. (Royal Zoological Society of New South Wales: Sydney.)

Whittington R. J. Connolly J. H. Obendorf D. L. Emmins J. Grant T. R. Handasyde K. A. 2002 Serological responses against the pathogenic dimorphic fungus Mucor amphibiorum in populations of platypus (Ornithorhynchus anatinus) with and without ulcerative mycotic dermatitis. Veterinary Microbiology 87 59 71 doi:10.1016/S0378-1135(02)00004-4

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