Authorities are using genetic testing to work out the origin of red imported fire ants discovered on a property at Tweed Heads, just south of the Queensland border.
The nest was discovered late on Tuesday by a pest control contractor.
It was destroyed within 24 hours.
Department of Primary Industries chief invasive species officer Scott Charleton said the incursion “was to be expected”.
“We are not naive to the fact that we will get new introductions into the state,” Mr Charleton said.
“We are prepared to deal with that as it turns up but it’s going to be a long battle.”
According to a statement released by NSW Agriculture Minister Tara Moriarty, a team surveyed a 500-metre-square area immediately surrounding the site to check for any other fire ant activity.
A thick mat of “rafting” fire ants on floodwater in south-east Queensland. (Supplied: Logan City Council)
It said the nest was immature, meaning it did not contain a reproductive queen ant.
Genetic analysis of the ants will help to determine their likely source.
The National Fire Ant Eradication Program (NFAEP) is tracing any movement of high-risk materials, such as turf and soil, to the property.
It is the first detection of fire ants in NSW since turf laden with the pests was brought to a property at Eureka, near Byron Bay, in November 2024.
The notorious pests are native to South America but have spread throughout large parts of south-east Queensland since they were detected in Brisbane in 2001.
Reece Pianta, from the Invasive Species Council, said it was heartening to see a rapid response by authorities.
“It looks like we’ve caught this one early and that just shows that the community is engaged in doing its part,”
he said.
Reece Pianta says fire ants only need to evade detection once to spread. (Supplied: Invasive Species Council)
Mr Pianta said a boost to biosecurity funding by the NSW and Queensland governments was welcome, but the Commonwealth needed to do more.
“We have a huge and growing nest population in south-east Queensland and if these get into some of those carrier materials they could spread all over the country,” he said.
“What we are seeing is that containment isn’t a solution, we need to catch every single one of these nests that are escaping.
“Fire ants only need to be successful in evading detection once to establish a new foothold somewhere in the country.”
Fire ants have spread throughout large parts of south-east Queensland. (Supplied: National Fire Ant Eradication Program)
A five-kilometre biosecurity zone has been set up around the Tweed Heads site to allow the area to be thoroughly checked and treated.
The zone is also designed to restrict the movement of high-risk materials from the area.
Biosecurity concerns
The NSW government has allocated $95 million to fire ant eradication.
A series of stop-and-check operations at the border have so far inspected 676 vehicles, with 24 sent back to Queensland after failing to meet entry requirements.
Minister for Agriculture Tara Moriarty said the government was committed to the task.
“Biosecurity is a shared responsibility, and we need everyone working together to manage the threat of fire ants,”
she said.
