OUR WORK
Australia is a world leader in species extinction and declines, largely due to invasive species.
Our Work | Ending extinction | Photo by Lindy Lumsden
Extinct: Southern day frog
- Common name: Southern day frog
- Scientific name: Taudactylus diurnisa
- Formal national status: Extinct
- Decade of extinction: 1970s
- Expert assessment of extinction causes: Invasive species (Chytrid fungus 98%)
The southern day frog was the first Australian frog lost to chytrid fungus (Batrachochytrium dendrobatidis), an Asian pathogen thought to have arrived in Brisbane in the 1970s. The day frog lived along streams in rainforest on Mt Nebo and Mt Glorious, less than an hour’s drive from the city. It inhabited 3 small mountain ranges, and was last seen in the d’Aguilar Range (near Brisbane) in 1975, a little further north in the Blackall Range in 1978 and in the Conondale Range in 1979.
Frog experts were baffled by its disappearance. They wondered about pollutants, climate change, UV light, disease, and natural population fluctuations, none of which seemed to fit the evidence. When more frog species disappeared further north in Queensland and chytrid fungus was found on some that died, it was accepted as the explanation for 2 southern Queensland extinctions – that of this frog and the southern gastric brooding frog, which lived alongside some of the same streams.
The southern day frog was the first species in Australia, and possibly the world, to go extinct from chytrid fungus. Photo: © Dr Hal Cogger
A decade after this frog disappeared, biologists Greg Czechura and Glen Ingram wrote down everything they knew about it in an article that paints a rich picture of a lost species. Southern day frogs were, as their name suggests, active by day and often energetic, moving across leaf litter and swimming in water. They would bask in shafts of sunlight or perch for long periods on warm rocks. When startled they would leap into fastflowing water to be swept away or dive down to hide among submerged stones and debris. Males made soft clucking calls from leaf litter along streams. At night they could be found in rock crevices, in burrows, under debris, in fallen palm fronds or clinging to vegetation. The females deposited their eggs in gelatinous clumps under rocks in the water. They were ‘abundant’.
While we can’t bring the tiny southern day frog, we can prevent future extinctions with urgent investment and action on invasive species.
Extinct
Australia has lost about 100 native plants and animals to extinction since colonisation, most of which were mainly due to invasive species. An estimated 27 of those extinctions occurred since the 1960s.
Learn more about some of Australia’s lost animals:
