Tinkling Frog

SPECIES Tinkling Frog 
TAXONOMY Taudactylus rheophilus
STATUS Endangered (ala.org.au); Protected under Australian Law

aka Northern Tinker Frog, Mountain Day Frog, Blunt-nosed Torrent Frog

The Tinkling Frog is known by several names including the Northern Tinker Frog and the Mountain Day Frog. It was named for its distinctive mating call that resembles the quick succession of a soft metallic tapping sound ‘tink tink tink tink’. It is listed as endangered and restricted to four mountaintops in Northern Queensland at elevations from 940 to 1400 meters. It displays a strong association with fast moving streams and is found under rocks within the stream banks where seepage and trickle areas occur. It is native to the Wet Tropics Bioregions. 

The Tinkling Frog is a small frog growing to 30 mm. With distinctive colouring and patterns, it ranges from grey to brown, reddish, or dark brown. The limbs have irregular blackish cross bands, and the digits are barred. The tips of the digits have small but conspicuous discs, and the toes are fringed but lack webbing.

Lifecycle
Although little is known about the species, it has been heard during the male calling period from December to May. Egg masses and tadpoles of the species have not been identified, but large eggs 1.8 to 2.4 mm diameter numbering 35 to 50 have been found in gravid females. Juveniles have been collected in December and May.

Threats
The Tinkling Frog has undergone a sudden range contraction and had apparently disappeared by October of 1991. After a period of apparent absence, five individuals were heard calling in a small, high altitude tributary of the Mulgrave River, and a further seven individuals were heard calling and captured. In 2013, intensive surveys under ideal weather conditions failed to locate the species, although the survey report acknowledges that the species is particularly hard to survey and thought to persist in a tiny population. 

The cause of the decline of the Tinkling Frog population remains unknown. In a survey in 1993, no obvious evidence was found of drought, floods, habitat destruction, or pollution by pesticides, inorganic ions, or heavy metals. Current research is examining the possibility that disease may have contributed to the decline of this species, and there is considerable circumstantial evidence to support this hypothesis. 

Chytridiomycosis is a highly infectious disease of amphibians, caused by the amphibian chytrid fungus. The fungus was first discovered in dead and dying frogs in Queensland in 1993 and has been directly implicated in the dramatic decline of at least ten frog species and the extinction of four others.

Updated 5 May 2021