Wallum sedgefrog
Photo: Scott Eipper, 2005
Common name: wallum sedgefrog
Scientific name: Litoria olongburensis
Family: Hylidae
Conservation status: The wallum sedgefrog is listed as Vulnerable in Queensland (Nature Conservation Act 1992) and nationally (Environment Protection and Biodiversity Conservation Act 1999). It is ranked as a medium priority under the Department of Environment and Resource Management Back on Track species prioritisation framework.
Description
The wallum sedgefrog is a small, slender tree-frog with a prominent pointed snout that protrudes over the lower jaw. Females (to 34 mm) tend to be slightly larger than males (to 26 mm). The skin on the top side is smooth and coloured grey-brown, beige or bright green, with occasional dark flecking. The granular underside is white except for the throat which is peppered brown. Distinguishing features include a dark brown stripe that runs from the snout through the eye and ear and an obvious white streak that starts below the eye and runs back to the flanks (side of animal between thigh and ribs). There may also be some blue colouration in the groin area. The toes are partly webbed and the finger discs and toe pads are prominent.
Habitat and distribution
Restricted to densely vegetated areas (wallum) in the coastal lowlands of south-east Queensland, the wallum sedgefrog is most common in swamps but is also known from creeks and reed beds around freshwater lakes. In all seasons the species can be found seeking refuge in swamps amongst sedges, reeds and ferns.
The species geographic distribution encompasses coastal lowland areas of south-east Queensland and north-east NSW, from Fraser Island, south to Woolgoolga. It is also known from several islands of the Queensland coast including Fraser, Bribie, Moreton and North Stradbroke. Due to pressures from urban development and the establishment of sand mining and pine plantations, the species is suspected to have suffered from significant habitat loss. However, large populations have persisted in protected reserves in both Queensland (Great Sandy, Noosa, Poona, Bribie Island, Blue Lake and Moreton Island National Parks) and NSW (Broadwater, Billinugel, Bundjalung, and Yuraygir National Parks and Tyagarah and Broken Head Nature Reserves).
Life history and behaviour
The wallum sedgefrog is a nocturnal species that breeds after rain in spring, summer and autumn. Males call from sedges above water and calling may be heard from September through to April. The wallum sedgefrog usually breeds in ephemeral (short lived) and semi-permanent swamps with thick emergent vegetation where eggs are laid singly in water at the base of sedges. Water at breeding sites is usually clear, heavily tannin-stained and acidic. The diet of this species consists of arthropods.
Threatening processes
Similar to other wallum frog species, the wallum sedgefrog is largely threatened by habitat loss and fragmentation from urban and agricultural development and pine plantation establishment. The species may also be adversely affected by habitat degradation due to trampling in tourist areas such as around the freshwater lakes of Fraser Island, weed invasion, inappropriate fire regimes, feral pigs, altered hydrological regimes and deterioration of water quality. Predation by mosquito fish Gambusia holbrooki and biocide use in urban and urban-fringe areas may pose additional threats.
Recovery actions
The recovery plan makes the following management recommendations for the conservation of wallum frogs:
- Protect wallum frog populations from further development and manage habitat to reduce the impact of identified threats.
- Conduct field surveys to clarify the impact and severity of threats, to inform management and ensure appropriate allocation of limited resources.
- Encourage stakeholder and community involvement in recovery activities.
- Rehabilitate degraded wallum frog habitat.
- Monitor frog numbers and distribution to determine if the species is recovering or in decline and to assess the efficacy of management activities.
What can be done to help this species?
- Contribute to recovery activities for this and other wallum frogs by ensuring that activities on, adjacent to or uphill from sites where wallum frogs occur do not alter water tables, hydrological patterns or affect water quality.
- Never release exotic fish into natural waterways, wetlands or dams (e.g. through disposal of aquarium collections, using exotic species as bait, or flushing fish down the toilet).
- Handling of frogs should be avoided to prevent introducing disease.
Related information
Hines, H.B., Mahony, M. and McDonald, K. 1999. An assessment of frog declines in wet subtropical Australia. Pp 44-63 in Campbell, A. (ed.) Declines and Disappearances of Australian Frogs. Environment Australia, Canberra.
Liem, D.S. and Ingram, G. J. 1977. Two new species of frogs (Anura: Myobatrachidae, Pelodryadidae) from Queensland and New South Wales. Victorian Naturalist 94, 255-262.
Meyer, E. Hero, J-M. Shoo, L. and Lewis, B. 2006. National recovery plan for the wallum sedgefrog and other wallum-dependent frog species. Report to Department of the Environment and Water Resources, Canberra. Queensland Parks and Wildlife Service, Brisbane.
Last updated 18 March 2011