Corroboree Frog

What are Corroboree Frogs?

Corroboree Frogs are Australia’s most iconic amphibian species, and are amongst the most visually spectacular frogs in the world. There are two closely related species of Corroboree Frog:

Both Corroboree Frog species are between 2.5 and 3 centimetres in length.

There are several differences between the two Corroboree Frog species including differences in their colour, patterns and even skin biochemistry.

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The Southern Corroboree Frog (Pseudophryne corroboree)
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The Northern Corroboree Frog (Pseudophryne pengilleyei)

Where Do The Corroboree Frogs Live?

Corroboree Frogs have a limited geographic distribution. The historic known range of the Southern Corroboree Frog is entirely within Kosciuszko National Park, from Smiggin Holes in the south, and northwards to the Maragle Range. Southern Corroboree Frogs only occur between about 1300 and 1760 m above sea level.

The historic known distribution of the Northern Corroboree Frog is throughout the Fiery Range and Bogong Mountains in Kosciuszko National Park, Bondo State Forest, Micalong State Forest, and Wee Jasper State Forest in NSW, and along the Brindabella Ranges in Namadgi National Park in the ACT, and Bimberi Nature Reserve and Brindabella National Park in NSW. These areas broadly represent three distinct geographic areas, with significant genetic differences between the pouplations and are treated as three separate management units: Southern Brindabella, Northern Brindabella, and Fiery management units. Northern Corroboree Frogs live between 750m and 1800m above sea level.

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The distribution of the Southern Corroboree Frog.

What Habitats Do Corroboree Frogs Use?

Habitat critical to the survival of Corroboree Frogs includes both breeding habitat and nearby areas where they feed. Corroboree frogs use a variety of habitat types for breeding including pools and seepages in sphagnum bogs, wet tussock grasslands, fens and wet heath. They also feed and shelter in montane forest, sub-alpine woodland and tall heath near breeding areas.

Corroboree Frogs tend to breed in water bodies that are dry during the breeding season. Outside the breeding season, Corroboree Frogs have been found sheltering in dense litter and under logs and rocks in nearby woodland and tall moist heath. Northern Corroboree Frogs have been found to move over 300 metres into surround woodland after breeding.

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Typical sub-alpine sphagnum bog pool used as breeding.
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Wet soak area in montane habitat with small pool used by the Northern Corroboree Frog for breeding.


Life-history and Ecology

Corroboree Frogs have a typical amphibian life-cycle with an aquatic tadpole stage and terrestrial frog stage. The diet of Corroboree Frogs consists mainly of small ants and, to a lesser extent, other invertebrates. Adult males move into breeding areas in early to late summer, and call from small chambers (nests) in moss or other soft vegetation and soil at the edges of the breeding pools. Typically, the pools are dry during the breeding season when the eggs are laid. The males have three call types; an advertisement call, threat call, and courtship call.

If a female is attracted to a male, she will lay her eggs in his nest. The male will remain in his nest through the breeding season and may accumulate many clutches. Clutch size for Corroboree Frogs is relatively low for a frog species; 16 to 38 eggs per female.

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Within the nest, the eggs develop to an advanced stage, before development stops and they enter what is called ‘diapause’. This effectively means that the embryos remain, without developing further, until flooding of the nest following autumn or winter rains stimulates them to hatch.

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After hatching, the tadpoles move out of the nest site and into the adjacent pool where they live for the remainder of the larval period as a free swimming and feeding tadpole. Corroboree Frog tadpoles are dark in colour, have a relatively long paddle shaped tail, and grow to 30 mm in total length. The tadpoles continue growing slowly, particularly over winter when the pool may be covered with snow and ice, until metamorphosis in early summer

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The majority of Southern Corroboree Frogs don’t reach reproductive age until four years from metamorphosis, although a small proportion of individuals reach sexual maturity in three years. Age to maturity for the Northern Corroboree Frog varies depending on the altitude of the population, with males from low altitude populations taking two years and males from high altitude sites taking four.