NEWS FROM THE AMPHIBIAN RESEARCH CENTRE

This article was written by Gerry Marantelli and originally published in "In the Spotlight" (Vol. 4, No. 3) - the report of the March 1998 meeting with Gerry as the guest speaker.

INTRODUCTION

The ARC was established during 1993-94 as a centre dedicated to research into, and conservation of, Australia's frogs. The ARC is not-for-profit and is self-funding. Our mission is to draw profits from ethical and sustainable use of frogs, as well as commercial operations relating to frogs, to support conservation and conservation research. We supply common species of frogs and tadpoles bred at the ARC, as well as enclosures, food, information, materials and other resources to those wanting to keep pet frogs. Stocks of frogs and tadpoles and cultured food insects are also sold for research that will benefit frogs. School visits and the supply of tadpoles and aquaria to classrooms raise additional revenue at the same time as educating and encouraging responsible attitudes towards wildlife. The ARC also provides placements to university and TAFE students studying suitable courses, who in turn provide a valuable labour resource and receive training and recognition. We operate from two sites, the first our main breeding and commercial centre, the other a site dedicated to quarantined facilities for threatened frog species.

PROGRAMS

Collaboration with the Victorian Department of Natural Resources and Environment in recovery processes for the Spotted Tree Frog (Litoria spenceri) and the Baw Baw Frog (Philoria frosti) has seen the establishment of captive programs for both species.

Work on the Baw Baw Frog began with egg masses collected in November 1997 and aims to develop protocols for captive rearing and breeding. To date some 90% of eggs collected have metamorphosed and reached six months of age. Over 200 frogs are now being raised for use in husbandry research and may ultimately provide stock for decline hypothesis testing, experimental reintroduction, display and as a safety net against further declines.

Work with the Spotted Tree Frog began in 1994 and the first captive spawning and raising of these frogs to maturity has already occurred. Frogs from three sites are now being housed. Animals from one site are the planned nucleus of a breeding colony to be used for the purposes of producing stock for experimental release to an extinction site after the removal of trout, the primary threatening process. Identification of chytrid fungus infections in two Victorian populations led to the collection of specimens as a precaution against population declines. In November 1998 the first captive breeding (eggs laid by long term captive frogs) was achieved. It is hoped that the tadpoles and young frogs raised from these eggs will assist in answering many important questions about the ecology of Spotted Tree Frog tadpoles and young frogs.

Work on both Northern and Southern Corroboree Frogs, Pseudophryne pengilleyi and Pseudophryne corroboree, began in early 1997 in cooperation with New South Wales National Parks and Wildlife Service and the University of Canberra. For the last two years eggs have been collected from sites in NSW and taken back to the ARC for raising. The project is housed in a dedicated facility, at our threatened frog centre and aims to: (1) Enhance wild recruitment by the collection of eggs and later release of captive assisted tadpoles. (2) Develop husbandry protocols for raising and breeding of both species of Corroboree Frogs. (3) Experimentally compare captive and wild mortality of larvae to establish which factors are responsible for low wild survival. To date over 1100 tadpoles have been released. Captive survival has been in excess of 85%, whereas field survivorship to the same stage was only around 10%. Monitoring of release methods has indicated that early release after snow melt gives the highest probability of survival to metamorphosis. Future releases will be timed to exploit this fact. The last release has only just been completed in late October 1998 and we are currently monitoring the released tadpoles at six sites to ensure they complete their development to metamorphosis.

Continuing work with the Great Barred Frog, Mixophyes fasciolatus, is yielding results on a number of fronts. The first captive spawning for this species in 1994 has been followed by regular breeding of a number of adult groups including two groups of captively bred frogs. The species was originally investigated as a potential analogue for development of captive protocols for other declining members of its genus. It has proven such an easy frog to work with that it is now one of our staples in the supply of tadpoles and young frogs for other research and as pets. An outbreak of disease in one group being raised led to work with Lee Berger at CSIRO's Animal Health Laboratories and the first infection experiments being conducted for the recently discovered chytrid fungus. Work at the ARC also led to the discovery that chytrids can be contracted by tadpoles but do not cause mortality until after metamorphosis. Investigations into the ecology of, and possible treatments for, chytrid fungus are continuing at the ARC in cooperation with CSIRO.

CONTINUING SUCCESS

The ARC's success in conservation programs is only possible through the generous donations of time, resources and money that we receive from people who believe in our mission. The centre is staffed by volunteers, without whom we could not take on the projects I have just reported on.

You can reach the ARC on +61 3 9354 4718.

author: Gerry Marantelli