An exciting scientific discovery was made when eight-year-old, Alice Dutton, a budding citizen scientist from Tecoma, recorded the call of the threatened Growling Grass Frog (Litoria raniformis) during a Birrarung Riverfest event at Spadoni’s Billabong in Yering.
According to Melbourne Water’s frog data, the species has not been recorded in this location for 24 years.
Alice captured the rare call using the Melbourne Water free Frog Census app on her mum Jess’s phone, and it was later verified by specialist ecologists who listen to and categorise every call submitted via the app.
Freshwater ecologist and Melbourne Water Waterwatch Coordinator Jane Petch, who was training people on how to use the app at the Spadoni’s Billabong event, said the recording was significant because there has been concerted effort by Melbourne Water and the Yarra Ranges Council to improve the habitat in that area.
“The Growling Grass Frog has not been officially sighted at Spadoni’s Billabong since 2000,” Ms Petch said.
“The recording of so many frog species at Spadoni’s Billabong reflects its improved ecological health thanks to the work of Melbourne Water to re-connect the Billabong to the Yarra River. This means that the Billabong now receives fresh inflows from the Yarra when river water levels are high.
“It’s incredibly rewarding to see these targeted conservation efforts supporting the return of local wildlife.”
The Growling Grass Frog was listed as vulnerable in Victoria under the Flora and Fauna Guarantee Act 1988 in 2003. This listing was made due to threats to the species’ habitat, including urban development, land clearing, and changes to water quality in its wetland habitats.
Jess, Alice’s mother, said the event had further sparked her daughter’s interest in frogs and the local ecosystem.
“We had never heard of the Growling Grass Frog before that day, but Alice was thrilled by her discovery and felt like a real citizen scientist,” Jess said.
“There were so many different frog calls in the area, and it was exciting to learn that we had captured a rare recording of a vulnerable frog species.”
Since the event, Alice has become an enthusiastic frog tracker.
“Alice and I now listen for frogs wherever we go, whether in the garden or on walks. She even gave a presentation to her class, and we’ve started making frog-friendly habitat at our home,” Jess said.
“I’d encourage kids to have a go at making a recording using the Frog Census app because you might discover something really special.”
Yarra Ranges Council Director for Planning and Sustainable Futures, Kath McClusky said the council has invested in habitat improvement works to enhance the area’s ecological health, including the restoration of the surrounding wetlands and floodplains.
“We are thrilled to hear about the return of the Growling Grass Frog to the Yarra Valley. The works undertaken at Spadoni’s Billabong are part of our ongoing commitment to improve local ecosystems and support biodiversity. Alice’s discovery underscores the value of our partnership with Melbourne Water and the community’s involvement in conservation,” she said.
Ms Petch added, “The data gathered through the Frog Census app is crucial for our conservation work. It helps inform Melbourne Water’s environmental projects and supports decision-making around the management of local waterways and wildlife.”
Frogs, as “indicator species”, are highly sensitive to changes in their environment, making them key to understanding the health of ecosystems.
In metro Melbourne, there are 16 species of frogs, including the vulnerable Growling Grass Frog, which is primarily found in Melbourne’s northern and western suburbs.