A national strategy is being developed to manage the spread and impact of a destructive, exotic clam that's been found in the Brisbane River.
It's been five weeks since the nation's first detection of the highly invasive freshwater gold clam, at several sites along the river.
The fast-growing, prolific breeder had been on a list of priority exotic pests Australia wanted to keep out due to its capacity for environmental harm.
Queensland's agriculture and fisheries department says Biosecurity Queensland has implemented a surveillance program to determine the extent of the incursion.
So far there's nothing to suggest it has reached other rivers.
The agency is working through the national Freshwater Vertebrates and Invertebrates Working Group to develop a national surveillance and preparedness strategy to manage the clam’s spread and impact.
"No positive identification of the clams in catchments other than the Brisbane River has been made so far," the department says.
"However, valuable information on the length of time these invasive clams have been present in known sites and the extent of their populations has been gathered."
It did not provide further details about how long the clam might have been present before it was detected.
A single clam can produce 400 offspring a day and up to 70,000 a year, meaning they can quickly form large populations capable of blocking waterways, driving down water quality and crowding out native species.
The clams can also clog up water-based infrastructure including hydroelectric dams, irrigation systems and water treatment plants.
It is very good at spreading, harnessing river water flows to disperse larvae over broad areas.
There have been no reports of impacts on water infrastructure in Queensland so far, the department says.
