The Green and Golden Bell Frog and Cane Toads in NSW

Michelle Stockwell was stopped by the flu before presenting at the October 2009 seminar, so we are pleased that she has agreed to talk to us again on the ongoing research findings in relation to the survival of the Green and Golden Bell Frog (G&GBF). She will be joined by Mike Mahony, University of Newcastle researcher, talking about the current state of Cane Toad management in Australia.

Michelle is from the Amphibian Research Group at the University of Newcastle's School of Environmental and Life Sciences and her ongoing research has focused on the G&GBF. The amphibian chyrtid fungus (Batrachochytrium dendrobatidis) is an aquatic pathogen that infects the outer epidermal layers of post-metamorphic amphibians causing the fatal disease chytridiomycosis. Chytridiomycosis has been implicated in the decline and extinction of over 200 amphibian species worldwide, one of which is the G&GBF (Litoria aurea). The G&GBF is an endangered pond breeding species that has declined from over 90% of its former range and currently occurs as a series of isolated populations in highly disturbed coastal environments. G&GBFs are very susceptible to chytridiomycosis and yet many remaining populations persist with low-level chytrid infections. This study investigated the role of environmental inhibitors of the chyrtid fungus in allowing the G&GBF to persist. The presentation will also cover implications of the Environmental Protection and Biodiversity Conservation Act with respect to this species.

Mike Mahoney is from the University of Newcastle where he is the resident frog expert. He was a member of the Federal Government's Cane Toad Advisory Committee. Many methods of biological control have been canvassed and closely scrutinised for Cane Toads. None have been successful to-date, and the most promising are years away from field testing and application. Mike will briefly review the various approaches and the current state of play.

The action of invasive animal and plants (weeds) is second only to habitat destruction as a cause of biodiversity loss, and Cane Toads are listed among 20 invasive vertebrates worldwide. There has been a considerable focus on managing the invasion of the Cane Toad both overseas and in Australia. Unfortunately, the story is not good; the toad is predicted to extend across the entire northern savannah (eastern and western Kimberleys) to the northern edge of the Great Sandy Desert. Additionally, the southwest of WA and much of the east coast is also suitable habitat.

Opinions on managing Cane Toads range from "no Australian animal has been shown to go extinct because of the toad, and we should not waste resources on the animal" to "it is a scourge that alters food webs and ecosystems" and should be removed without further consideration. Some of the scientific evidence and management strategies being pursued in northern Australia will be discussed. However, it is bitter sweet irony that we have spent more and know more about toads than any native amphibian.

About HEI

HEI was established in 1988 to provide a forum for the interaction of people working in environmentally oriented fields in the Hunter Region. HEI is a non profit organisation, managed by a Committee and operating under a formal Constitution.

The objectives of the HEI are to:

*Propagate and promote the knowledge and skills of those involved in the environmental field;

*Disseminate information related to environmental disciplines to practitioners and the community;

*Increase environmental awareness;

*Provide impartial comment or assessment, where appropriate, on environmental issues; and

*Promote the advancement of environmental management.

The objectives above are fulfilled mainly through seminar presentations by guest speakers on a broad range of environmental topics.