Publications
Wildlife Australia, April 1997
ISBN 0 6422 1400 X
1. Family Leptodactylidae
2. Scientific Name Rheobatrachus silus
3. English Name Gastric Brooding Frog, Platypus Frog, Southern Gastric Brooding Frog
4. Intraspecific taxa
None.
5. Species survival status
Endangered. Described in 1973, and until 1980 was considered secure by those familiar with the species in the wild. However, the last individual was seen in the wild in September 1981 (Richards et al. 1993). A small captive population at the University of Adelaide survived until 1983, indicating that this decline was due to a local environmental factor. Assessments of its current status range from endangered to extinct.
6. Former distribution
Confined to the Conondale and Blackall Ranges in south east Queensland.
7. Current distribution
It is unknown whether this species persists anywhere within its former range.
8. Habitat
Closely associated with creeks and rock pools in rainforest and tall open forest with rainforest elements.
9. Reasons for decline
Unknown. As for Taudactylus diurnus, with which it co-existed, Tyler and Davies (1985) found no obvious evidence that over-collecting, pollution from logging or gold-panning, or drought were responsible for the population decline.
10. Conservation reserves on which species occurs
Qld: Kondalilla and Conondale National Parks.
11. Other public lands on which species occurs
Qld Sunday Creek and Kenilworth State Forests.
12. Other land on which species occurs
None known.
13. Is knowledge about species adequate for objectives and actions to be defined accurately?
No. While there is some information available on the biology of this species there is a lack of knowledge necessary for successful captive breeding. In a captive colony, in a simulated stream environment, no breeding took place over seven years. While males amplexed with females, ovulation did not occur, apparently because females lacked mature follicles. More information is required on the nature of follicle stimulating hormone (FSH) in this and other species.
14. Recovery Plan objectives
14.1. To verify the continued existence of populations of R. silus anywhere within its former geographic range.
14.2. To ensure that frog conservation objectives are incorporated into all appropriate land management decisions by raising awareness of the declining frog problem in all levels of the government and the community.
15. Management actions completed or under way
15.1. Intensive and extensive surveys have been conducted by the Queensland Museum, University of Queensland and by the Qld Departments of Natural Resources and of Environment, as part of a recovery program for threatened frogs of Qld and northern NSW (Coordinator: K.R. McDonald, Qld Department of Environment).
15.2. A draft recovery plan has been prepared for this species in conjunction with Taudactylus diurnus (Martin and McDonald 1996).
15.3. A draft Species Management Profile has been prepared by the Qld Department of Natural Resources to provide forestry field staff with information about the species and advise on any current management requirements.
16. Management actions required
Management actions outlined in the draft recovery plan include:
16.1. Monitoring.
16.2. Dissemination of information to conservation agencies, State government departments, community groups, industry, local authorities and the general public.
16.3. Encouragement of community participation in frog survey and monitoring.
16.4. Consultation with land managers to ensure habitat protection.
17. Organisations responsible for conservation of species
Qld Department of Environment.
18. Other organisations involved
Queensland Museum, Qld Department of Natural Resources, University of Queensland Conondale Range Committee, amateur frog clubs.
19. Can recovery plan be carried out with existing resources?
No
Efforts to rediscover this species should be made in conjunction with Taudactylus diurnus, with which it co-exists. Funding outlined in the draft recovery plan, which includes both species, includes salary costs for running workshops on threatened frogs and training volunteers (part time), travel costs and equipment. Total budget $21K (over five years for two species).
Total (average cost per species) $10.5K
References:
Martin, W.E. and McDonald, K.E. 1996. Draft recovery plan for Rheobatrachus silus and Taudactylus diurnus. Unpublished report to the Australian Nature Conservation Agency, Canberra.
Richards, S.J., McDonald, K.R. and Alford R.A. 1993. Declines in populations of Australia's endemic tropical rainforest frogs. Pacific Conservation Biology 1: 66-77.
Tyler, M.J. and Davies, M. 1985. The Gastric Brooding Frog. pp. 469-470 in Biology of Australasian frogs and reptiles. Eds G. Grigg, R. Shine and H. Ehmann, Royal Zoological Society of New South Wales, Mosman.
Herpetological authorities consulted:
C.J. Corben, G.V. Czechura, M. Davies, G.J. Ingram, K.R. McDonald.