Northern Corroboree Frog (Pseudophryne pengilleyi)
The Northern Corroboree Frog (Pseudophryne pengilleyi) is a small but distinctive frog with bright yellow-green and black stripes on its upper surfaces and a broadly marbled ventral surface of black and white or black and yellow. Adults attain 2.5-3 cm body length. The Northern Corroboree Frog differs from the closely related Southern Corroboree Frog ( P. corroboree ) by having more green in the yellow stripes which also tend to be narrower. Northern Corroboree Frogs are also slightly smaller than Southern Corroboree Frogs, which occur in Kosciuszko National Park in NSW.
The Northern Corroboree Frog is confined to the high country of the ACT and adjacent NSW, along the Brindabella and Bimberi Ranges and throughout the Fiery Range and Bogong Mountains, where they occur in waterlogged grasslands, heath, sphagnum moss bogs and adjacent woodlands. The ACT population is located almost entirely in the subalpine areas of Namadgi National Park, with an important stronghold being the internationally recognised Ginini Flats wetland complex.
Adult Corroboree Frogs spend most of their time in the woodlands (where they also over-winter) and move into the sphagnum moss bogs and other waterlogged areas during summer to breed. Females lay clutches of around 25 eggs in damp vegetation at the margins of pools. The eggs hatch into tadpoles when the water level rises following rain or snow melt (which may be anytime during autumn, winter or spring). The tadpoles metamorphose into frogs during the following summer (one year after eggs were laid) and move out of the bogs to the woodlands. In a further two years time they are mature and return to the bogs to breed. Small black ants that are abundant in the bogs and woodlands feature prominently in the diet of Corroboree Frogs, though they will eat any invertebrate small enough to fit in their mouth.
Conservation Threats
Corroboree Frogs were once abundant in suitable habitat (bogs, fens and surrounding woodlands) but populations of both species have declined over the past 20 years and are now on the verge of extinction in the wild. In the ACT it is estimated less than 50 Northern Corroboree Frogs remain in the wild from the original populations. The decline of Corroboree Frogs is due to disease caused by the introduced Amphibian Chytrid Fungus, which has caused the decline and in some cases extinctions of frog species world-wide. Other threats include climate change, drought, inappropriate fire, disturbance from introduced animals (pigs and horses) and weeds. Northern Corroboree Frogs are listed as threatened in the ACT, NSW and at the national level.
Conservation Actions
As part of the National Recovery Program for Corroboree Frogs and the ACT Action Plan for the Northern Corroboree Frog, a captive population was established at Tidbinbilla Nature Reserve in 2003 from eggs collected in the wild. The program has successfully bred Northern Corroboree Frogs in captivity, enabling the species to be maintained as a self-sustaining captive insurance population to help avoid extinction. Some of the Northern Corroboree Frogs bred in captivity at Tidbinbilla are being released back to Namadgi National Park to bolster wild populations and to provide the opportunity for natural disease resistance to develop amongst wild breeding populations.
The next step in the ACT Government recovery program for Northern Corroboree Frogs is the construction of five specialised outdoor enclosures at Tidbinbilla Nature Reserve. The outdoor enclosures will enable Northern Corroboree Frogs to be raised and bred in habitat that more closely resembles the frogs' natural habitat in woodlands and sphagnum moss bogs.
More information
Contact
Email environment@act.gov.au or phone Access Canberra on 13 22 81.