The Action Plan for Australian Frogs
By
Michael J. Tyler
with the assistance of the Editorial Advisory Committee
Wildlife Australia, April 1997
ISBN 0 642 21400 X
Recovery Outline No. 19: Baw Baw Frog
1. Family
Leptodactylidae
2. Scientific Name
Philoria frosti
3. English Name
Baw Baw Frog
4. Intraspecific taxa:
None.
5. Species survival status
Endangered. The current population of adult males is estimated to be 1-2% of the 10,000-15,000 adult males estimated to be on the Baw Baw Plateau in 1983 and 1984 (Hollis 1997).
6. Former distribution
Confined to an area of about 80 km2 on the Baw Baw Plateau, Victoria.
7. Current distribution
Restricted to 80 km2 on the Baw Baw plateau in Victoria. Evidence obtained by Hollis (1995) indicates a major decline in population numbers and distribution since the survey of Malone (1985a). The distribution of P. frosti will be confirmed during a proposed montane slopes survey.
8. Habitat
Breeding and non-breeding habitats are restricted to sub-alpine and montane vegetation communities at 1100-1560m altitude. Breeding habitats occur predominantly along seepage lines within or at the periphery of frost hollows and gullies. Non-breeding habitats include breeding habitats in addition to snow-gum woodland and montane wet forest, where frogs shelter beneath dense vegetation, roots, logs, rocks and leaf litter.
9. Reasons for decline
Unknown. Major threats are disturbance and changes to habitat characteristics, such as vegetation clearing and soil disturbance associated with roads, ski developments and timber harvesting; predation by introduced predators; invasion of habitat by introduced plants; air and water pollution; and long and short-term climate change. Possibly also susceptible to increase in ultra-violet radiation.
10. Conservation reserves on which species occurs
Vic: Baw Baw National Park
11. Other public lands on which species occurs
Vic: Mt Baw Baw Alpine Resort. Highly likely to occur in adjoining State Forest (Eastern and Western Tyres, Tangil and Thomson Forest Management Blocks) on the south-east to south-west escarpment of Baw Baw Plateau. Likely to also occur in adjoining State Forest (Bells and Cascade Forest Management Blocks) on the north and north-east escarpment.
12. Other lands on which species occurs
None known.
13. Is knowledge about species adequate for objectives and actions to be defined accurately?
No. Basic biological information is available, but little is known of the ecological requirements of
P. frosti. The major threats appear to be habitat loss, change and fragmentation although the causes of decline have not been identified.
14. Recovery Plan objectives
14.1. To research and document the biology and ecology, to assist with effective recovery action and management prescriptions.
14.2. To determine the major causes of decline across the geographic range and prevent the continuing decline in distribution and abundance.
14.3. To protect the breeding and non-breeding habitats.
14.4. To monitor and assess landuse activities that have potential to impinge on the survival of the species.
14.5. To minimise and mitigate the impacts of habitat disturbance, change and fragmentation.
15. Management actions completed or under way
The Victorian Department of Natural Resources and Environment has undertaken extensive surveys, including preliminary assessment of the breeding habitat and micro-habitat characteristics (Hollis 1995), research on dispersal and calling activity, collection of climatic data, vegetation mapping and digitising, increased community awareness and habitat protection activities. A Recovery Plan has been prepared (Hollis 1997).
16. Management actions required
Implement the Recovery Plan, including:
16.1. Monitor the population over five consecutive years, initially to accurately assess population status and trends, and extent of occurrence.
16.2. Survey the montane slopes between 1000 and 1300m.
16.3. Obtain information on growth, age at sexual maturity and longevity from analysis of skeletal chronology.
16.4. Detailed analysis and modelling of long term climatic data, including seasonal and daily variation in precipitation and temperature, particularly over the last ten years.
16.5. Detailed documentation of floristic and structural characteristics of breeding habitat.
16.6. Diet analyses of specimens preserved at the Museum of Victoria.
16.7. Investigate current recruitment and compare with previous estimates.
16.8. Predator scat collection and analysis to determine whether introduced animals (fox, dog and cat) predate on P. frosti and to what extent.
16.9. Develop effective captive husbandry techniques to increase embryonic, larval and adult survivorship rates.
16.10. Increase public awareness of the sensitivities and significance of sub-alpine and montane habitats for threatened species such as P. frosti, and monitor impacts of recreational activities.
16.11. Investigate the effects of ultra-violet radiation on embryonic and larval development of P. frosti and other amphibians on the Baw Baw plateau.
17. Organisations responsible for conservation of species
Victorian Department of Natural Resources and Environment, Alpine Resorts Commission.
18. Other organisations involved
University of Melbourne Department of Zoology, La Trobe University Department of Zoology.
19. Can recovery be carried out with existing resources?
No.
P. frosti is a 'high profile' monotypic genus, unique to Victoria and is in a rapid rate of decline. The Recovery Plan for P. frosti estimates $502,400 is needed to implement the Recovery Plan.
Total $502.4K
References:
Hollis, G.J. 1995. Reassessment of the distribution, abundance and habitat of the Baw Baw Frog (Philoria frosti): preliminary findings. Victorian Naturalist 112(5):190-201.
Hollis, G.J. 1997. Recovery Plan for the Baw Baw Frog (Philoria frosti). Unpublished report to the Australian Nature Conservation Agency, Canberra.
Malone, B.S. 1985a. Status, distribution and ecology of the Baw Baw Frog (Philoria frosti). Arthur Rylah Institute Tech. Rep. No. 36. Department of Conservation, Forests and Lands, Victoria.
Malone, B.S. 1985b. Mortality during the early life history stages of the Baw Baw Frog (Philoria frosti). pp 1-5 in Biology of Australasian Frogs and Reptiles. Eds G. Grigg, R. Shine and H. Ehmann, Surrey Beatty and Sons, Sydney.
Herpetological authorities consulted:
G.J. Hollis, W. Osborne.