Along Monbulk Creek in south-east Melbourne, platypus hunt for prey. It’s a busy business, being a platypus.
In normal times, he will eat 20 to 30 percent of his body weight each day. If she is breastfeeding and taking care of babies, she will need to eat 80 percent of her body weight.
No one knows for sure how many of these elusive creatures remain in this stretch of the creek, but Melbourne’s waterways and wetlands research manager Rhys Coleman estimates there could be as few as 30.
In nearby Ferny Creek, no platypus have been detected since 1997, while in Upper Dandenong Creek, none have been detected since 2011.
But in Monbulk Creek, there is still hope. During the most recent survey, conducted last month, researchers captured and released eight platypus, including a young female.
The discovery of the young platypus was encouraging, Coleman said, offering hope for future generations of this endangered species.
“It’s always a great relief to see that they breed, and that’s an important thing for us, to try to create an environment where they can reproduce,” he said.
The Victorian government listed the platypus as an endangered species in 2021, after captive populations disappeared during and after the Millennium Drought.
Against this background, Melbourne Water – in partnership with organizations including the University of Melbourne, Yarra Ranges Council and South East Water – is making a concerted effort to protect the isolated residents of Monbulk Creek.
With $4 million in funding, and support from the Victorian government, Melbourne Water is rolling out Australia’s first “smart” water program that aims to manage water levels in the creek.
During heavy rains, storm water systems that flow into the creek can erode creek walls and rapidly raise water levels, trapping and drowning platypus in their burrows.
Climate change means the risk of drought and low flows is also increasing.
Under the scheme, households near the stream have been provided with free rain tanks that will be connected to smart technology. Sensors in nearby tanks, streams and lakes will give authorities the ability to monitor water levels – and demand – in real time.
Before a forecasted heavy rain, tanks can be partially emptied to capture rain runoff on the roof and control stormwater runoff into the creek. During the dry season, tanks will release flow into a dry stream.
It is expected that the strategy will also help several thousand species including crustaceans and water bugs used by the platypus.
“They’re very concerned about having enough water in the creek, and one of the reasons is they need to eat a lot … a lot from dusk to dawn, they go out and feed,” Coleman said.
“And one of the big things we’re focusing on is increasing the flow of dry weather in the fall to be able to sustain food and help women recover and prepare for the next season.”
Modeling included in the Victorian government’s 10-year Healthy Waterways Strategy, released in 2018, predicts that without any changes to stormwater management systems, the length of platypus-intolerant waterways will increase by approximately 1200km.
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Bianca Hall is the environment and climate reporter for The Age, and has worked in a variety of roles including as a senior reporter, city editor, and in the federal politics office in Canberra.Connect through X, Facebook or email address.
