newy.com.au – More than 100 tonnes of a prohibited aquatic weed have been removed from 25 Anna Bay properties after Port Stephens recorded its first known frogbit infestation.
Port Stephens Council said all known sites had been treated during a 20-day operation covering more than 9000 square metres of water. Staff will continue monitoring the area for regrowth.
The infestation was discovered on an Anna Bay property by the council’s Environmental Operations Team during routine biosecurity inspections. Council officers then worked with landowners to trace and clear the weed from surrounding properties.
Frogbit can spread rapidly across dams, creeks and wetlands, forming dense mats that block sunlight, reduce oxygen levels and threaten native aquatic life. It can also obstruct drainage systems and prevent livestock from reaching water.
The floating weed can make deep water appear to be solid ground, creating a danger for people, pets and livestock.
Frogbit is classified as prohibited by the NSW Department of Primary Industries and Regional Development because of the risk it poses to natural waterways. It is illegal to buy, sell, trade or move the plant within or into NSW.
Council environmental operations team leader Brayden Luke said officers used approved herbicides and mechanical removal to deal with the infestation.
“Working with multiple landowners, the team treated the infestation using a combination of approved herbicide controls and mechanical removal. All known sites have been successfully treated and cleared, but we will need to continue to monitor the area closely to ensure it remains free of this weed,” Mr Luke said.
It remains unclear how frogbit reached Anna Bay, although the council believes it may have been mistakenly discarded from an aquarium.
The weed can be identified by its small, round and glossy green leaves and tiny white flowers. Residents who find suspected frogbit in a creek, farm dam or pond have been warned not to disturb or remove it because broken fragments can float away and start new infestations.
Sightings can be reported to the NSW Biosecurity Helpline on 1800 680 244 or Port Stephens Council at weeds@portstephens.nsw.gov.au.
