Biodiversity and Conservation

, Volume 24, Issue 10, pp 2583–2592 | Cite as

Island provides a pathogen refuge within climatically suitable area

  • Michelle P. Stockwell
  • Deborah S. Bower
  • Loren Bainbridge
  • John Clulow
  • Michael J. Mahony
Original Paper


Surveillance of pathogens can lead to significant advances towards making effective decisions in research and management for species threatened by disease. Batrachochytrium dendrobatidis has been a major contributing factor to the global decline of amphibians. Knowledge of the distribution of B. dendrobatidis can contribute to understanding patterns of species decline and prioritizing action. Therefore, we surveyed four spatially distinct populations of a B. dendrobatidis susceptible species, the green and golden bell frog (Litoria aurea), for evidence of infection in the population. Three mainland populations were infected at a prevalence of 3.5–28.3 %, with median infection loads of 0.28–627.18 genomic equivalents (GE). Conversely, we did not detect infection in an island population 3 km from the mainland; the isolation and infrequent visitation of the island suggests that the pathogen has not arrived. Management actions for B. dendrobatidis and conservation of susceptible frog species are heavily dependent on the presence and absence of the pathogen in the population. Prevention of the accidental introduction of B. dendrobatidis and safe guarding genetic diversity of L. aurea is necessary to preserve unique diversity of the island population, whereas containment and control of the pathogen can be directed towards mainland populations. Knowledge of disease dynamics also provides a context to understand the ecology of remaining populations as variation in the physiology or habitat of the mainland populations have facilitated persistence of these populations alongside B. dendrobatidis. Other islands should be a priority target in disease surveillance, to discover refuges that can assist conservation.


Litoria aurea Batrachochytrium dendrobatidis Conservation Infectious Chytridiomycosis Amphibian 



The authors thank Kerry Darcovich, Katie Oxenham, Andrew Hamer, Graham Pyke and Arthur White for support with site access and field work and to the many volunteers that helped with surveys. Thanks also to Kim Colyvas and Annelie Wenslandt for assistance in manuscript preparation. This study was supported by the Kooragang Wetland Rehabilitation Project, the Barker Family Scholarship, the Tom Farrell Institute for the Environment and the Wildlife Preservation Society. All work was conducted in accordance with the Australian Government National Health and Medical Research Councils Code of Practice for the Care and Use of Animals for Scientific Purposes and under the approval of the University of Newcastle’s Animal Care and Ethics Committee.


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Copyright information

© Springer Science+Business Media Dordrecht 2015

Authors and Affiliations

  • Michelle P. Stockwell
    • 1
  • Deborah S. Bower
    • 1
  • Loren Bainbridge
    • 1
  • John Clulow
    • 1
  • Michael J. Mahony
    • 1
  1. 1.Conservation Biology Research Group, School of Environmental and Life SciencesThe University of NewcastleCallaghanAustralia

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