Wallum froglet
Common name: wallum froglet
Scientific name: Crinia tinnula
Family: Myobatrachidae
Conservation status: The wallum froglet is listed as Vulnerable in Queensland (Queensland Nature Conservation Act 1992) and New South Wales (NSW Threatened Species Conservation Act 1995). It is ranked as a high priority under the Department of Environment and Resource Management Back on Track species prioritisation framework.
Description
The wallum froglet is a small frog that grows up to 20 mm in length and has a pointed snout. The skin on the dorsal side (back or top side) may be smooth or have irregular rounded projections. Irregular dark markings, or stripes are evident on the dorsal side and colouration ranges from light grey, beige, red-brown to dark-brown. The ventral surface (front or bottom side) is granular, off-white with dark grey speckling or dark grey with white speckling and a distinct stripe runs down the throat and belly. The fingers and toes are unwebbed and toes do not have flattened disks or pads at their tips. Tadpoles are grey or brown above with irregular darker markings and have an oval shaped body and a tail that is 1.5 times the body length.
The wallum froglet is similar to other co-existing Crinia species (C. parinsignifera, C.signifera), although it can be distinguished by the faint row of white dots down the center of the throat, and a more pointed snout that projects beyond the lower jaw.
Habitat and distribution
Restricted to freshwater swamps in lowland coastal areas, this species is found in associated vegetation communities such as heath, sedgeland and woodland on nutrient-poor sandy soils. Acidic swamps and lakes in these areas provide essential breeding habitat for wallum-dependent frog species. This species has also been observed in disturbed heath habitat.
The wallum froglet only occurs in lowland coastal habitats in south-east Queensland and north-east New South Wales and on the sand islands off the Queensland coast (Fraser, Bribie, Moreton and North Stradbroke Islands). The species range once extended from just north of Bundaberg in Queensland to the Sydney area in New South Wales. Although large populations have persisted in some of Queenland's protected areas, its distribution has been significantly reduced and fragmented.
Life history and behaviour
The wallum froglet is a nocturnal, terrestrial (lives on the land) species that breeds in acidic ephemeral (short lived) swamps. Breeding usually occurs in autumn or early winter, but has been recorded in all seasons following rain. During the season, males call from the base of sedges near water or atop matted sedge clumps. Calls are usually a short, high-pitched 'tcheh'. Spawning (egg laying) has been observed in July and August, and takes place in acidic waters where eggs are attached to submerged vegetation.
Threatening processes
The wallum froglet has experienced significant population declines and range reductions due to habitat loss, fragmentation and modification from agricultural and urban development, establishment of exotic pine plantations and sandmining. Other potential threats to this and other wallum-dependent frogs include: predation of eggs and larvae by introduced fish; habitat degradation (from weed invasion, inappropriate fire regimes, feral pigs, drainage of habitat, deterioration of water quality, use of biocides in weed and mosquito control); and disease spread through inappropriate handling.
Recovery actions
The recovery plan (PDF, 518K)* makes the following management recommendations for the conservation of wallum froglets:
- Protect wallum frog populations and manage remaining habitat to address threats.
- Rehabilitate degraded wallum frog habitat.
- Learn more about the impacts of known and potential threats to inform management.
- Conduct surveys to clarify the distribution of wallum frog species, determine abundance and assess habitat condition.
- Protect wallum frog habitat on freehold land through voluntary conservation agreements such as Nature Refuges.
What can be done to help this species?
- To protect habitat for wallum frogs, maintain vegetative buffers around known breeding sites, hydrological regimes and water quality to enable movement of animals between populations and catchments.
- Ensure that activities on, adjacent to or uphill from sites where the wallum froglet occurs do not alter water tables, hydrological patterns and 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
Ehmann, H. 1997. Wallum Sedge Frog. Pp 182-187 in Threatened Frogs of New South Wales: Habitats, Status and Conservation. Frog and Tadpole Study Group of New South Wales Inc. Sydney, NSW.
Hines, H.B. Mahony, M.J. and McDonald, K.R. 1999. An assessment of frog declines in wet subtropical Australia. In Campbell, A. [ed.] Declines and Disappearances of Australian Frogs, Environment Australia, Canberra.
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.
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Last updated 11 March 2011