Council’s eco-friendly fight against invasive weed

Fraser Coast Regional Council has unleashed a microscopic powerhouse—no bigger than a grain of sugar—to combat one of the region’s fastest-spreading aquatic weeds while reducing its environmental footprint.

Fraser Coast Regional Council Senior Biosecurity Supervisor Andrew Hatch said the new Salvinia Weevil Breeding Facility in Oakhurst will not only drastically reduce this invasive weed but will also save Council time and money while decreasing chemical use in local waterways.

“Salvinia molesta is one of the world’s most aggressive aquatic weeds, doubling in size every three days and forming thick mats that disrupt ecosystems,” said Mr Hatch.

“Our new Weevil Breeding Facility enables us to breed Salvinia weevils—tiny beetles no bigger than a grain of sugar—that feed on the weed, weakening its structure and slowing its spread.

The $37,500 Salvinia Weevil Breeding Facility was funded by the Queensland Government as part of the Queensland Feral Pest Initiative.

Member for Maryborough John Barounis said investing in biological control methods like this is key to managing Salvinia in a sustainable, cost-effective, and environmentally friendly way.

“While complete eradication is nearly impossible, this facility gives us a powerful tool to control the spread and protect local ecosystems,” he said.

“These funds have been made available from the Department of Primary Industries.”

Mr Hatch said the facility includes one control tank, and three poly-tanks dedicated to breeding weevils, with each tank capable of sustaining around 10,000 weevils.”

“The first batch of weevils was released into three Council-managed sites and several privately owned dams in January.  Early indications show the weevils are effective, with their impact to continue to be closely monitored.”

Fraser Coast Regional Councillor Michelle Byrne said the control of Salvinia molesta is a high priority for Council as identified in our Biosecurity Plan.

“This innovative, eco-friendly approach not only protects our waterways but saves time and money,” she said.

“The facility will improve Fraser Coast’s waterways and provide vital support for private land holders managing this invasive weed.

Cr Byrne said Council will also use drones to spray large, affected areas, complementing the work of Salvinia weevils to improve weed management and reduce chemical use.

“Last year marked the first time Council used aerial spraying, making the process more efficient and eco-friendly.

“Previously, treatments were applied from a boat, taking over 40 hours and requiring about 130 litres of herbicide, whereas drone spraying used just 36 litres and was completed in three hours.”

“Council currently manages Salvinia levels in hundreds of waterways across the Fraser Coast and assists private land holders in controlling the weed on their properties.

“Council is committed to maintaining our open spaces by using sustainable practices that preserve the environment and enhance community enjoyment.”

For more information on Council’s Biosecurity Plan, head to https://www.frasercoast.qld.gov.au/downloads/file/1618/biosecurity-plan-2022