Cost of fire-ant outbreak in Australia could be much higher than ‘flawed’ earlier prediction, data shows

<span>Red imported fire ant (<em>Solenopsis invicta</em>). Data shows the invasive species will cost Australians more than $22bn by the 2040s if left to run rampant.</span><span>Photograph: SUPPLIED/PR IMAGE</span>
Red imported fire ant (Solenopsis invicta). Data shows the invasive species will cost Australians more than $22bn by the 2040s if left to run rampant.Photograph: SUPPLIED/PR IMAGE

The cost of a widespread fire ant outbreak may be far higher than predicted in “flawed” government modelling provided to ministers in the fight against the highly invasive species, new research suggests.

The Australia Institute data, released on Wednesday, found that red imported fire ants will cost Australians more than $22bn by the 2040s if left to run rampant, with the benefits of achieving eradication estimated to be three to nine times greater than the $3bn needed to achieve that eradication.

The findings are in contrast to a 2021 Biosecurity Queensland Department of Agriculture and Fisheries-commissioned report that indicated the cost benefits of eradicating the fire ants were generally positive but in some scenarios “quite poor” and even loss-making.

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The highly invasive insect is believed to have entered Australia in the 1990s and was discovered at Brisbane port in 2001. It has spread across more than 700,000 hectares in south-east Queensland and outbreaks were recently detected in northern New South Wales.

The policy thinktank found the government-commissioned analysis, entitled Assessing the Impacts of the Red Imported Fire Ant, was unusual in that it was limited to a 15-year timeframe when most fire ant economics modelling is conducted over 20 to 30 years. It also ignored the $2.5bn a year in damage that fire ants will cause beyond 2035, the authors said.

“The key flaw is that it only looks at costs over 15 years,” the research director of the Australia Institute, Rod Campbell, said.

By changing the timeframe to 20 years and keeping all other parameters the same, the case for funding fire ant eradication efforts went from “marginal” to “compelling” because costs rise rapidly as the pest becomes more established.

“If you just extend their analysis for another five years you start capturing some of those benefits or avoided costs, then suddenly the economic case for investing in fire ant eradication goes from kind of marginal to absolutely compelling,” he said.

The National Fire Ant Eradication Program spans state, territory and federal governments and has been allocated $593m federal and state funding from 2023 to 2027.

This is well below the $200m to $300m a year over 10 years that is necessary to “avert, by 2032, predicted annual impact and control costs of $2bn, and up to 140,000 medical consultations”, as recommended in a separate strategic review.

Dr Minh Ngoc Le, post doctoral fellow at the Australia Institute, said that “eradicating fire ants is not only one of the best environmental policies governments could pursue, but also one of the best economic policies”.

The Biosecurity Queensland report stated that the 15-year timeframe was chosen “even though only a small proportion of total potential infestation would occur in this time period, so as to maintain relevance for current decision makers and budget allocations.”

A spokesperson from the National Fire Ant Eradication Program said it “has been very clear that the costs of living with fire ants far outweigh the cost of eradication.”

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“This position has been informed by multiple independent cost benefit studies over the past decade,” the spokesperson said.

The report was not made public until almost two years after it was completed. It was provided to ministers and senior federal agriculture department officials when fire ants breached containment in 2023, said the Invasive Species Council advocacy manager, Reece Pianta.

He said the revised modelling “paints an even more dire picture and should prompt further fire ant action”.

“We’ve been calling for greater transparency including early public disclosure of reports like this to ensure governments are making the best decisions about fire ants. It raises questions about how invasive species are modelled, particularly around the impacts on our natural environment,” he said.

“Governments have never invested enough to deal with fire ants in Australia – modelling which has underevaluated the fire ant threat has contributed to that.”

The Senate inquiry’s report into the national response to fire ants is due to be released on Thursday, a month after the conclusion of three days of hearings in which the Senate committee, led by Nationals senator Matt Canavan, heard the National Fire Ant Eradication Program was an “absolute shambles” and lacked transparency.