The endangered Growling Grass Frog is continuing to thrive at Bendigo Water Reclamation Plant in Epsom thanks to the diverse and protected habitat the plant provides.
Coliban Water Executive General Manager Service Delivery Danny McLean said the frog, named for its distinctive call, had been found in healthy numbers during the latest annual survey.
“Our plant has 67 hectares of lagoons, treatment ponds and dams that have a high biodiversity value.
“Our treatment lagoons provide an ideal habitat with plenty of algae and ample rocks for protection from predators. This allows the frogs to emerge, feed and bask,” Mr McLean said.
“The plant treats Bendigo’s wastewater to a quality where it can be used to irrigate public gardens, sporting facilities and farms in the Bendigo area. Alternatively, it can be released into the environment to supplement local waterways.
“Both the treatment process and the treated water are providing excellent habitat and environmental benefits for this endangered species,” Mr McLean said.
Approximately 140 frogs were recorded during each of the two survey periods. Each survey period ran for two nights. The use of additional survey techniques this time has improved the detection of frogs across the plant.
“It involved active searching, the use of audio playback, and small, low cost, acoustic devices called ‘audiomoths’ to record frog calls at optimal times,” Mr McLean said.
“Growling Grass Frogs were recorded at 13 of the 23 waterbodies assessed at the plant during the survey periods in the 2020/21 breeding season.
“We’ve seen a positive change in numbers from what was recorded last year, which is fantastic and in line with what was recorded in 2018/19.
“We’re pleased to see Growling Grass Frogs in promising numbers once again,” Mr McLean said.
The survey results come amid the release of Coliban Water’s latest Environmental Policy Statement, which demonstrates the organisation’s commitment to the highest levels of environmental stewardship and sustainability.
“In particular, one of our Strategy 2030 strategic directions is Healthy People and Environment,” Mr McLean said.
“This is where our focus will remain. Caring for Growling Grass Frogs at our plant in Epsom is a great example of how policies like this translate into tangible actions.
“The species is listed as threatened in Victoria and vulnerable under the Environment Protection Biodiversity Conservation Act 1999 and is protected by law,” said Mr McLean.
“We are committed to protecting the species and give special consideration for its habitat when planning projects at the plant or making significant changes to our operational activities.”
The survey consultants also recorded 68 other species of native fauna.
“This included seven species of frogs, 52 birds, 2 bats, the Eastern Long-necked Turtle and the Eastern Grey Kangaroo,” Mr McLean said.
The Growling Grass Frog was once found throughout south eastern Australia but is now only found in isolated populations throughout central and northern Victoria due to habitat loss, predators and disease.