Floodwaters that have devastated a region in an ex-cyclone's wake have revealed a new threat - a global super pest.
Fire ants have been spotted "rafting" and travelling along floodwaters in southeast Queensland, sparking fears its threat will spread.
Scenic Rim locals south of Brisbane have sighted the floating fire ants as many communities mop up in the aftermath of ex-Tropical Cyclone Alfred.
"It's a big concern," Invasive Species Council Advocacy Manager Reece Pianta told AAP.
"We had a very big problem in the fire ant number and density before the cyclone.
"I am concerned it is going to reach new properties and people will find themselves with new infestations near rivers or where low lying flooding occurred."
Recovery efforts are underway in Queensland's southeast and northern NSW after floodwaters inundated communities, cut power and damaged roads.
Health authorities had warned people to stay away from flooding with hidden dangers including faeces, chemicals, industrial waste, snakes, sharp objects and a potentially deadly bacterial disease.
Soil-borne Melioidosis has already claimed 16 lives in north Queensland in 2025 after record February rainfall triggered floods that forced hundreds to evacuate.
Fire ants have emerged as the latest flooding concern, furthering the risk of spreading to other parts of Australia.
Fire ants are considered one of the worst invasive species to reach Australia, potentially causing more economic damage than cane toads, rabbits and feral cats combined.
Authorities have been battling to stamp out the highly aggressive, exotic insects for more than two decades, with heavy infestations already reported in southeast Queensland.
"People need to be careful around these fire ant rafts and need to be checking their properties," Mr Pianta said.
"If they didn't have them before they might have them now because the floodwaters have brought them to their property."
Known for their painful stings, fire ants pose a risk to humans, native wildlife and the economy.
Originally from South America, fire ants are projected to slash agricultural output in Australia by 40 per cent if unchecked, according to recent data.
"Fire ants are lethal. People have died of fire ant attacks in the United States," Mr Pianta said.
He urged state and federal governments to ramp up fire ant suppression and containment work.
The National Fire Ant Eradication Program plans to eradicate the pest from Australia by 2032.
Federal, state and territory governments have committed $1.28 billion by 2027 to combat the fire ant menace.
