Common name: northern tinkerfrog
Scientific name: Taudactylus rheophilus
Family: Myobatrachidae (Australian water frogs)
Conservation status: This species is listed as Endangered in Queensland (Nature Conservation Act 1992) and nationally (Environment Protection and Biodiversity Conservation Act 1999). It is considered a low priority under the Department of Environment and Heritage Protection Back on Track species prioritisation framework.
This species is a small frog, with a robust body and truncated snout. Males are 23.8-32 mm long and females 24.1-30.5 mm. The upper surface is smooth or finely granular, and may be grey-brown, reddish or dark brown in colour, with irregular darker markings. A narrow pale greyish streak runs from the eye to the groin, bordered below by a broad black band whose lower edge breaks up into a marbled or reticulate pattern on the flanks.
There is a faint, pale transverse bar between the eyes and a pale glandular patch runs from the angle of the jaws to the base of the forearm. The ventral surface is smooth, brown in colour, with conspicuous, irregular, creamy-white markings. The limbs have irregular blackish cross bands and the digits are barred with dark brown and creamy grey. The tips of the digits have small but conspicuous discs, the toes fringed but without webbing.
Habitat and distribution
The northern tinkerfrog is a cryptic species found under rocks, roots and logs in seepage and trickle areas beside fast-flowing rainforest streams. The adults are mainly nocturnal, though they may be active on overcast days.
Historically this species was restricted to four mountain tops at altitudes of 940-1500 m within the Wet Tropics from Thornton Peak to Mt Bellenden Ker. This species has undergone a sudden range contraction and had apparently disappeared by October 1991. Sporadic records were confirmed from Mt Bellenden Ker and Mt Lewis up until 2000. No confirmed observations have been made since then and the continued existence of the species is questionable.
Life history and behaviour
The northern tinkerfrog is mainly active at night although males have been observed calling on overcast days. The call has been variously described as a soft metallic tapping sound, "tink tink tink" repeated 4-5 times in quick succession, or a gentle rattling sound. Males form a chorus, calling from under rocks or roots and may be partly in water.
Little is known of its developmental biology, but females can carry 35-50 large (1.8-2.4 mm diameter) eggs. The tadpole has not been described. Juveniles have been collected in the months of December and May.
The northern tinkerfrog is one of seven species of frogs occurring in the upland rainforest streams of north-eastern Queensland which have undergone rapid and substantial population declines. Surveys during 1991-1992, 1993 and 1994 failed to find any individuals.
The causes of the decline remain unknown, with no obvious evidence that drought, floods, habitat destruction or pollution by pesticides, inorganic ions or heavy metals were responsible for the population declines. Current research is examining the possibility that a fungus may have caused the decline of the stream dwelling frogs of the Wet Tropics. Information on disease investigations and management can be located at the James Cook University website.
The Recovery plan for the stream-dwelling rainforest frogs of the wet tropics biogeographic region of north-east Queensland 2000–2004 makes the following management recommendations
- Monitor historical localities to detect recovery.
- Investigate disease in related species.
- Develop and refine husbandry techniques for rainforest stream dwelling frogs.
- Train park staff and community volunteers in identification of this species.
- Implement monitoring by park staff of select locations within the national park estate where the northern tinkerfrog formerly occurred.
Cogger, HG 2000. Reptiles and Amphibians of Australia. Reed New Holland, Sydney.
Curtis LK, Dennis AJ, McDonald KR, Kyne PM, and Debus SJS 2012. Queensland’s Threatened Animals, CSIRO, Victoria, Australia
Department of Sustainability, Environment, Water, Population and Communities. 2012. Taudactylus rheophilus Northern tinkerfrog in the Species Profile and Threats Database.
Northern Queensland Threatened Frogs Recovery Team, 2001. Recovery plan for the stream-dwelling rainforest frogs of the Wet Tropics biogeographic region of north-east Queensland 2000-2004. Report to Environment Australia, Canberra. Queensland Parks and Wildlife Service, Brisbane.