A leading Australian entomologist is touting the success of a 'simple, low-cost' option for fighting fire ant nests.
It's certainly not the kind of equipment you can pick up at Bunnings, but this large contraption could play a role in countering a serious threat moving around the country. Australian researchers are trialling alternative methods to tackle one of the worst invasive pests on the continent as red imported fire ants continue to pop up in new areas.
As the desperate push to eradicate the 'super pest' from Australia's environment rolls on, researchers at the Southern Cross University in northern NSW say a pilot study has shown a non chemical treatment has proven effective in killing the dangerous ants at three sites where it was trialled.
Professor of Entomology Nigel Andrew set out to validate the hot water injection method as a potentially more environmentally-friendly way of destroying nests.
"The main reason why we wanted to look at it is because it has been used in the US successfully, and currently in Australia, we are sort of restricted to using the chemical treatments and growth inhibitors (baits that prevent reproduction)", Professor Andrew told Yahoo News.
"Essentially we wanted to see if the findings in the US could be replicated here, to put it out there as another part of our toolkit."
The method involves injecting hot water at 90°C into a nest at around 5-litres per minute to flood the site and hopefully kill the colony. Larger nests can take about 15 minutes to fully flood, the researchers said.
At one site the team reported 100 per cent nest death three weeks after the second treatment and 92 per cent nest death at a second site. A third, larger site with 80 nests, initially showed about half the success rate after the first round of treatment.
"It's not the sort of rig that you probably be go and hire from Bunnings," Professor Andrew admitted, referring to the large apparatus used to flood the nests with boiling water. But it's something he believes could be deployed by local councils as another way to help stop the spread of fire ants as authorities work towards eradication.
Those carrying out the eradication efforts have faced intense pushback from a minority of property owners in the region concerned about the chemical treatments being used on their properties. Professor Andrew believes the hot water method could help "bring everyone on board" and also makes sense from an ecological standpoint.
"The first defence that our environment has, once the fire ants are in are all our native species, we have a range of native ants, beetles, spiders, wasps, that they're our first line of defence, and so we don't want to kill them.
"We need to use chemicals in a very sort of specific way, rather actually a broad brush approach," he argued.
"In agriculture, we know from the use of broad scale insecticides when you kill off all the other invertebrate species, you leave the environment open to invasive species colonising much quicker."
Professor Andrew believes a non chemical solution should be considered as part of the puzzle.
"Sporting fields can remain open, organic farmers can safely export their produce, landholders wanting a non-chemical option to treat fire ants on their property can all be treated effectively using this option," he said.
Earlier this week, the National Fire Ant Eradication Program (NFAEP) announced it was reviewing its treatment approach for managing fire ants on organic properties and suspending treatment and would no longer use treatments with genetically modified organism (GMO) material on such properties.
A spokesperson for the program told Yahoo News authorities believe chemical treatments offer the best chance at properly beating back the incursion, adding that authorities have "embedded innovation" into their approach.
"This includes a strong commitment to research, assessment, and trials of new methods to eradicate this super pest," they said. "Fire ant eradication treatments are specifically designed to stop the queen from producing viable, reproductive offspring, ultimately destroying the colony.
"To date, our approach is the only proven eradication treatment effective at the scale required to eradicate this super pest from Australia. Hot water treatment is not feasible given the vast areas requiring eradication treatment," the spokesperson told Yahoo.
The technique investigated by Professor Andrew is far from new. US entomologist Walter Tschinkel - author of The Fire Ants and Ant Architecture: The Wonder, Beauty, and Science of Underground Nests, explored the potential use of hot water treatments nearly two decades ago.
"Hot water is an extremely effective and specific killing agent for fire ant colonies, but producing large amounts of hot water in the field, and making the production apparatus mobile have been problematical," he wrote in the Journal of Insect Science back in 2007.
Native to South America, the ants spread into the northern continent of America about a century ago and have invaded more than a dozen US states, costing the country's economy billions of dollars a year.
"It is important to note that the United Sates is no longer attempting eradication and focuses on managing fire ants and the associated harms to communities," the NFAEP spokesperson told Yahoo.
"This is the context in which they use hot water. Australia remains committed to eradication. Our internal assessment of hot water has demonstrated significant limitations, particularly at scale, though we always consider valid research."
The spokesperson also noted the impact of its chemical treatments on other species "are minimal and short-term" and are largely confined to similar ant species.
Red imported fire ants were first detected in South East Queensland in 2001 with hopes the nationally cost-shared program can achieve eradication of the pest by 2032.
It's thought that about 174,000 people could develop severe allergic reactions if the species became endemic in Australia.