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They are one of the world’s worst invasive species, and now, more than two decades after they are believed to have arrived in Australia, the country is launching the second-biggest biosecurity operation in its history to eradicate red imported fire ants.
State, territory and federal agricultural ministers met in Melbourne on Wednesday and agreed to spend $411.4m over the next 10 years, endorsing a biosecurity operation second only in size and ambition to the country’s successful eradication of bovine tuberculosis, which started in the 1970 and took nearly three decades.
The eradication effort has been spearheaded by an unlikely alliance of environmentalists and farmers, who are equally concerned about the devastating effects the ants would have on Australia’s lifestyle, economy and environment if they become established.
First detected in Australia in 2001, but probably brought in years earlier, the South American “red imported fire ants” are thought to have caused dozens of deaths in the United States, where they have become established and cost the economy $7bn a year.
In Australia seven separate incursions have been recorded – four in Brisbane, two elsewhere in Queensland and one in Sydney – with time-limited and underfunded control programs managing to eradicate all but one incursion.
The one incursion remaining – in the suburbs of Brisbane – was first observed in 2001, although according to experts, was probably present up to ten years earlier.
Without a major eradication push, experts say outbreaks will spread and lead to an uncontrolled and established population that will change Australia forever. According to the an independent review conducted for the federal government, it would have a bigger impact than rabbits, cane toads, foxes, camels, wild dogs and feral cats combined.
A map showing the parts of Australia vulnerable to fire ant invasion. Photograph: Invasive Species Council
“If Australia fails to eradicate fire ants almost no corner of the continent will be safe from these menacing predators,” said the chief executive of the Invasive Species Council, Andrew Cox.
Ben Hoffman, an exotic ant specialist at the CSIRO in Darwin, agreed. “This species is ranked as one of the worst invasive species in the world for very good reason,” he said. “You only need to look to the United States to see what would happen here.”
The ants are extremely aggressive, attacking en masse and inflicting an itching and burning sting that can last an hour. Secondary infections from the stings can be serious, and in rare cases allergic reactions have killed people.
The Queensland Department of Agriculture and Fisheries (QDAF) describe the species as a “social menace”.
“Encounters with fire ants usually involve dozens of ants moving quickly and undetected. By the time they sting, a large number of ants could be on your body, all stinging at once. Stings from fire ants can cause a painful, burning itching sensation, which can last for up to an hour. Multiple stings give the sensation that the body is on fire.”
Modelling conducted by the CSIRO has shown the ants, if established, could infest every state and territory in Australia, with prime habitats extending all the way around the coast and throughout the tropical north.
Experience from the US shows people’s lives can be severely affected. When that happens, “people do not have picnics on the lawn, go barefoot or sit or lie on the ground, or even stand for too long in one spot because they will be stung”, warned QDAF.
The ants can also have severe environmental and economic impacts.
One study estimated fire ants could cost $45bn over 30 years in south-east Queensland alone.
The ants have the potential to eradicate some native animals, feeding voraciously on them. Since fire ants also eat seeds and pollinating animals and undermine root systems, they could cause major changes to entire ecosystems.
That would damage world heritage sites, hurt tourism and cost the beef and cattle industry $308m a year in production losses and control costs – cutting margins of farmers by 40%.
In May, the National Farmers’ Federation, Queensland’s farming lobby group AgForce and local government groups joined the Invasive Species Council, signing an open letter calling for a major eradication push.
“This aggressive stinging ant is a major threat to the survival of young calves and cattle in south-east Queensland,” said Charles Burke, the then chief executive of CEO AgForce. “Human lifestyles and farming procedures would change forever if red imported fire ants are not eradicated.”
Cox said: “Fire ants can rapidly expand in numbers and have the potential to invade more than 99% of the nation. Once out of control, fire ants would threaten every aspect of Australian life, including our farming communities, schools, sports grounds, tourism industries and unique natural heritage.”
According to all available analyses, the $38m per year eradication program agreed to on Wednesday is predicted to have a huge cost-benefit ratio. Every dollar invested is expected to pay back at least $25 of avoided costs – with the government’s independent review finding that was likely an underestimation.
The government’s independent review concluded a program that spent $38m a year for 10 years had a 95% chance of successfully eradicating the ants from Australia.
Hoffman said Australia had become a world leader in fire-ant eradication. Of the five successful eradications that have occurred, one of them in Gladstone is already the largest ant eradication for any species in the world.
“What’s been achieved is the absolute gold standard,” he said. “What’s left is the largest population of a single incursion. It’s still highly ambitious but it’s the closest anyone has been to eradicating the ant after it’s been established anywhere in the world.”
He said the lessons learned in the eradications so far – and the successful containment of the continued incursion in Brisbane – needed to be applied and scaled up to eradicate the country of the pests.
“Theoretically, if it’s resourced appropriately, it can be achieved because we’ve done it so many times already just on smaller scales.”
With that money, an independent taskforce will be set up, and a veritable war waged on the insects, beginning in September.
About $24m will be spent each year on baiting, aircraft hire for aerial bait bombing, direct injection of bait into nests, field staff and remote sensing including cameras, more aircraft and all-terrain vehicles.
A further $14m will be spent each year on other eradication activities including community engagement, research, movement controls and odour detection dogs.
Cox said the funding had put Australia on a “war footing”.
“Our fire ant fighters have finally been given the war chest they need to eradicate deadly fire ants from Australia,” he said.
Both Cox and Hoffman said eradication was a huge effort, but just as important would be improved biosecurity to avoid further incursions.
“We’ve been getting one new outbreak of fire ants every year until this year,” said Cox. “We have to beef up our biosecurity efforts to make sure we don’t undermine all of that investment.
“This is a huge achievement and shows a clear resolve from all governments and political parties. No one in the world has attempted anything like this.”
(THE GUARDIAN)
