AN outbreak of fire ants at Fisherman's Landing in Gladstone is likely to have arrived from the southern United States.
The dangerous invasive insects were discovered at Fisherman's Landing, Yarwun, about six months ago, and have since been found on Curtis Island.
A Department of Agriculture, Fisheries and Forestry spokesperson said $3.295 million has been provided for the next two-and-a-half years for eradicating fire ants in Gladstone through the National Red Imported Fire Ant Eradication program.
Eradication initiatives include aerial baiting, movement restrictions and surveillance.
"Genetic testing reveals the ants have come from the southern United States. However, how they got to Gladstone is unknown," the spokesperson said.
"There is no evidence that anyone has breached quarantine requirements through the importation of goods or equipment into Gladstone.
"The program is working closely with all businesses working or operating within the Fisherman's landing and Curtis Island areas to eradicate the fire ants. All parties have been incredibly supportive and accommodating of the program's requirements."
Visiting Gladstone earlier this month, Agriculture Minister Barnaby Joyce said fire ants were a threat to national biosecurity.
"If you let this problem get out of hand, it will come back to bite you," he said.
"This is not just a problem for Gladstone. If fire ants spread across the country and into backyards, it will be a horror story."
Fire ants in America have cost the country $7 billion. The pests have painful stings, and feed on small ground fauna such as insects, lizards, frogs, birds and mammals.
As such, they could displace or eliminate some of Australia's unique native species.
They also could affect the agriculture industry because they attack young animals, and invade the food and water supplies of animals.