THE Queensland Government’s new year-round fire ant eradication plan has been criticised by one of the world’s leading authorities on invasive ants, who warns winter baiting is scientifically flawed.
Dr Joshua King, a biology professor at the University of Central Florida with a PhD in entomology, specialises in ant ecology and invasive species management. His research has helped shape environmentally conscious pest control strategies, particularly for red imported fire ants (RIFA).
He told the Ipswich Tribune that baiting during colder months was unlikely to succeed.
“Even if bait was picked up, it’s doubtful it would be shared effectively within colonies,” he said.
“The ants are less active and less inclined to forage or feed the brood in cooler conditions.”
The winter baiting plan – announced by Premier David Crisafulli – marks the first time the National Fire Ant Eradication Program (NFAEP) will pursue treatments year-round.
Mr Crisafulli said the government was “listening to the most cutting-edge science”.
However, Dr King said decades of published data on fire ant behaviour did not support that claim.
“Foraging is typically seen between 15°C and 43°C, with peak activity around 22–36°C,” he said.
“Soil temperature about 2cm below the surface is the most reliable predictor.”
He warned that even minor shifts in timing could sabotage the winter baiting operation.
“UV light and moisture will degrade the bait’s active ingredients,” he said. “If baits go out even a few days early, they lose efficacy.”
Dr King also noted that most bait product labels recommend no more than two or three applications per year and advise against use during rain or extreme weather conditions.
“Winter baiting is generally not done,” he said. “A week-long warm spell might help, but otherwise, it’s not the norm.”
Dr King won the 2023 Theodore Roosevelt Genius Prize and US$100,000 for his non-toxic method to manage fire ants, which eliminates the need for harmful pesticides.
The prize recognises innovators who develop technology-driven solutions to solve major conservation challenges.
The NFAEP defended its new approach, saying it was based on Australian trials conducted in 2024 at both inland and coastal locations. Treatments were applied at six different points during winter, with results monitored for up to 20 weeks.
“Treatment effects were evident within 12 weeks, and in some cases, persisted for up to 20 weeks,” a spokeswoman said.
They said the research showed fire ants remained active throughout winter in Southeast Queensland, where daytime temperatures ranged between 8°C and 22°C.
The spokeswoman said local field observations supported these findings, and the data was reviewed and endorsed by the then-National Exotic Invasive Ants Scientific Advisory Group.
She added that the program was operating within existing resources and that winter would be used to maintain momentum heading into the warmer months.
The NFAEP declined to show the Tribune the results of its trial but said the findings would be made public soon.
Dr King remained unconvinced.
“I’d want to see clear evidence of fire ants actively collecting bait at temperatures well below 22°C,” he said.
“It is very important to note that no eradication program has ever succeeded in preventing fire ant establishment and spread over larger areas and longer time spans.
“This is not anecdotal but has unfortunately been repeatedly demonstrated. The clearest example is, of course, the successful invasion of the southern US, in the face of one of the largest invasive insect eradication programs in history.
“Ultimately, the attempts at eradication and prevention of further invasions by fire ants have not only failed, but the very actions taken to eliminate the fire ant ultimately hastened its establishment and spread.
“Given the reality of this extremely challenging invasive species, and the lessons that failed eradications have taught us, it is extremely important that the NFAEP consider the costs and benefits of enacting a widespread toxic baiting program.”