Defence bases pose a “huge risk” when it comes to stopping the spread of invasive fire ants in Australia, with experts suggesting there has been “a massive surveillance failure” on the commonwealth-owned properties.
Fire ants have been detected at eight defence sites in Queensland. Seven are within the state’s 700,000-hectare fire ants containment zone, which stretches from the Gold Coast to Caboolture.
But the eighth infestation is outside that zone – at Swartz Barracks in Oakey, 130km west of Brisbane. That infestation was discovered in April and at least 128 nests have been destroyed since then.
The defence department insists specialist pest managers are routinely engaged across defence properties but experts believe the nests at Swartz Barracks went undiscovered for years.
The Invasive Species Council is so worried that its chief executive, Andrew Cox, has written to the defence minister, Richard Marles, calling for an urgent audit of all defence properties across Australia.
“Fire ants are likely to have been at [Oakey] for several years indicating a massive surveillance failure on defence land,” Cox wrote to Marles, who is also the deputy prime minister, in April.
“The detection at Oakey must trigger an audit of defence force land in Australia for fire ant infestation.”
Queensland is home to the largest army base in the country and 14 significant defence facilities. Across Australia, there are 3m hectares of defence land.
Defence sites inside Queensland’s red imported fire ants (Rifa) containment zone include Victoria, Gallipoli, Damascus and Kokoda barracks as well as the Greenbank vehicle training centre and RAAF base Amberley.
Earlier this week, the federal minister for agriculture, Murray Watt – who received a copy of Cox’s letter – replied that the Oakey detection was a “high priority” for defence and the national fire ant eradication program.
Watt said that, in addition to the 128 nests being destroyed, 192 hectares were under surveillance and 7,151 hectares were being treated around Swartz Barracks.
The minister said the federal and Queensland governments were “working on improved Rifa management, surveillance and suppression activities on defence bases in Queensland” – particularly Greenbank and Amberley.
The Swartz nests were linked to existing populations in the containment zone with ants being transferred via contaminated turf, not military vehicles, the minister’s letter states.
A defence department spokesperson added that specialist pest managers were “routinely engaged by defence to deliver land-management services across the estate including monitoring and control programs”.
“Defence facilitates access to enable external parties to undertake biosecurity management activities on defence land in accordance with defence policy,” they said.
Reece Pianta, the advocacy manager at the Invasive Species Council, said the nature of defence land – which is often used for weapons testing or artillery ranges – meant the sites were “not visited enough and they are not maintained from an ecological point of view”.
“I’ve had reports of fire ants personnel having difficulty accessing defence land because it’s restricted land by its very nature,” he said.
“I’m keen to hear how they are going to improve fire ants management on defence land. I think defence land is a huge fire ant risk – it’s a risk they have moved from that [Oakey] site and we should check. I suspect there are undetected fire ant nests on defence land.”
Pianta said it was “disappointing” the federal government was not surveying defence land. He also asked: “What else is on these sites that is an invasive risk to other species? There is a lack of transparency.”
The Invasive Species Council spokesperson claimed the nests at Swartz Barracks – which were located in a quadrangle – had been there for two to five years and were reaching the density of Rifa reported in some parts of the US.
The independent Invasive Species Council was formed in 2002 “to seek stronger laws, policies and programs to keep Australian biodiversity safe from weeds, feral animals and other invaders”, according to the council’s website.
A 2021 strategic review commissioned by the Queensland government into what has now become a $1.2bn fire ant elimination program warned that defence land was “of particular concern” in the fight against the pest. That report was not made public until 2023.
The review panel, led by Dr Helen Scott-Orr, singled out Greenbank reserve and RAAF base Amberley as “two major parcels” of at-risk defence land.
Greenbank “could well act as a reservoir for reinfestation if it were not included in any nearby suppressive program. Likewise the Amberley airbase provides ideal Rifa habitat”, the review stated.
In March, a Senate committee chaired by Matt Canavan heard the scope of the Rifa problem was immense. Should the ants spread through Australia’s habitat, the impact would be worse than the combined effects of rabbits, cane toads, foxes, camels, wild dogs and feral cats, the inquiry was told.
Up to 650,000 Australians could be stung annually and the beef industry could be slashed by 40%.
The defence spokesperson said the department regularly reinforced biosecurity obligations and “guidance on how to identify red imported fire ants at defence sites to all defence personnel, via base-wide communications” and worked with the agriculture department to “ensure robust biosecurity policies and processes are in place to manage risks from pests, weeds and pathogens”.
They said the eight infested defence sites were now managed in accordance with fire ant eradication program guidelines. The most recent treatment at Oakey was completed on 30 April.
“As Oakey is located outside of the biosecurity zone, the biosecurity zone protocols did not previously apply at that site,” the spokesperson said. “The increased protocols have now been applied.”
Restrictions at Swartz Barracks prevent the movement of soil, rock, mulch, potted plants or other similar material from the base, the department said.
A spokesperson from the national fire ant eradication program said eradicating fire ants would take a “whole-of-community” approach and that under the Biosecurity Act 2014 “all Queenslanders have a general biosecurity obligation to manage biosecurity risks and threats on property they own, manage, or work on”.
