Breeding habitat use and the future management of the critically endangered Southern Corroboree Frog

Authors

  • David Hunter,

  • Will Osborne,

  • Michael Smith,

  • Keith McDougall


  • David Hunter is a threatened species officer with the New South Wales Department of Environment and Climate Change (PO Box 733, Queanbeyan, NSW 2620, Australia; Tel.: 02 62297115; Fax. 02 62297001; Email: david.hunter@environment.nsw.gov.au). Will Osborne is a senior lecturer in the faculty of science at the University of Canberra (Canberra, ACT 2601, Australia; Tel. 02 62015377; Fax. 02 62015305; Email: will.osborne@canberra.edu.au). Michael Smith is a natural resource manager on Christmas Island (Christmas Island National Park, PO Box 867, Christmas Island, Indian Ocean, WA, 6798. Tel. 08 91648700. Fax. 08 91648755. Email: michael.j.smith@environment.gov.au). David, Will and Mike have been collaborating on threatened frog recovery programmes over the past twelve years, with a particular focus on declining frog species in the Southern Highlands of New South Wales. Keith McDougall is a threatened-species officer with the Department of Environment and Climate Change (PO Box 733, Queanbeyan, NSW 2620, Australia; Tel.: 02 62297111; Fax. 02 62297001; Email: keith.mcdougall@environment.nsw.gov.au). Keith has been researching the dynamics of montane bog systems over the past 30 years, in particular their response to cattle grazing and fire.

Abstract

Summary  The Southern Corroboree Frog (Pseudophryne corroboree) is one of Australia's most critically endangered frog species. The species occurs entirely within Kosciuszko National Park, which has a history of cattle grazing (up to the 1970s). A consequence of cattle grazing has been a significant reduction in the extent of montane and sub-alpine peat-bog systems that the species uses as breeding habitat. Furthermore, climate change and associated increased wildfire frequency is expected to further reduce the extent and quality of peat bogs throughout the Australian Alps. In this study, we investigated habitat selection for breeding pools and nest sites within peat-bog systems in order to inform the conservation management of the species and guide other management practices being undertaken in peat bogs where this species occurs. Occupancy of breeding males at bog pools was found to be positively associated with increasing pool area, water depth and mid-day temperature, and negatively associated with extent of bare substrate. The majority of breeding pools identified were ephemeral. Nest sites within vegetation where males call and where females deposit their eggs were located at mid-elevations in a range of vegetation types, with the majority of nests being within moss and sedge dominated by Sphagnum cristatum and Empodisma minor. We also found that male nest sites were not randomly distributed within the edges of pools, but were more often located in areas of loose vegetation. These results highlight the potential sensitivity of the Southern Corroboree Frog to predicted changes in peat-bog systems resulting from climate change such as earlier drying and a possible reduction in the size of bog pools. A monitoring programme focused on key features of the breeding habitat should be undertaken to provide a basis for developing and assessing management actions implemented in peat bogs occupied by this species.

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