Northern Territory Government Newsroom

Ken Vowles, Minister for Primary Industry and Resources congratulates Larrakia Traditional Owners and the Department of Primary Industry and Resources for eradicating an aquatic pest from One Mile Dam.

“The year long collaborative project is a great biosecurity success story, in that a feral fish species has been completely eradicated in the Top End.” Mr Vowles said.

Gambusia holbrooki—also known as the eastern gambusia, mosquito fish, or plague minnow—was discovered in a drain near the One Mile Dam community in 2014.

Gambusia was introduced in Australia as a biological mosquito control, but it had little impact on mosquito numbers. The fish proliferated and outcompeted many of native fish and frogs. 

Senior Traditional Owner of Larrakia country Eric Fejo said once they had become aware of the noxious fish in the water, they were keen to see it eradicated before it spread.

“We received support from neighbouring Aboriginal groups to help us get rid of the nasty critter,” he said.

“Traditional Owners from as far as Kakadu were also worried about that fish getting into their pristine waters—that’s our ‘bush telegraph’ working for us.”

As the dam is a registered sacred site, the Fisheries unit of the Department of Primary Industry and Resources (DPIR) consulted with the Aboriginal Areas Protection Authority (AAPA) and local community members in helping to eradicate the aquatic pest.

Prior to starting the Gambusia eradication project at One Mile Dam, native fish and freshwater turtles were removed from the dam and transported to Darwin Aquaculture Centre for safekeeping.

DPIR’s Senior Indigenous Policy Manager Robert Carne said rotenone—the same tree root-derived poison that Aboriginal people traditionally used to harvest freshwater fish—was used to eradicate the gambusia.

“The organic compound rapidly biodegrades, so harmful residues were minimal and only small quantities were required,” he said.

“Once the pest was eradicated, the native fish and turtles held at the aquaculture centre were returned to the dam to help rebuild their populations.”

This project is dedicated to the memory of the late Mr D Timber of One Mile Dam community.

To report a suspected marine pest and for more information on aquatic biosecurity:

https://nt.gov.au/marine/for-all-harbour-and-boat-users/aquatic-pests-marine-and-freshwater

MEDIA CONTACT: Sheena Dunne 0427 687 079