Red fire ants are forming rafts to travel on flood waters in the northeastern Australian state of Queensland, with the extreme weather threatening a countrywide spread of the highly invasive species.
“The recent heavy rainfall and wild weather in the region could accelerate the spread of fire ants, one of the world’s worst invasive species,” Reece Pianta, advocacy manager at Australia’s Invasive Species Council (ISC), warned in a statement Tuesday.
“Fire ants are more active before or after rainfall and can form large floating rafts which move with water currents to establish footholds in new areas,” Pianta said, urging residents to be on the lookout. The ISC shared a video on social media of the fire ants traveling in raft formation.
“‘It’s really easy to do your part. Just take a picture of any suspicious ants and report it,” he added.
Queensland has seen brutal weather and heavy flooding in recent weeks. Last month, the city of Cairns was cut off by torrential rains brought by the remnants of Tropical Cyclone Jasper. Flooding also left many of the more than 150,000 inhabitants stranded on their rooftops.
Modeling by the ISC suggests fire ants will spread to “every corner of Australia” if the outbreak in Queensland isn’t curbed.
The ISC said in its statement that it recently received a 70 million-Australian-dollar ($46 million) four-year commitment from the state of Victoria to go toward the national fire ant eradication program, which Pianta said means eradication is still possible.
Originally from South America, the red imported fire ant, Solenopsis invicta, is an omnivorous species that destroys crops and livestock alike. Its venomous sting causes pustules and allergic reactions and can kill a human. Over the past century it has spread throughout much of the United States, Mexico, the
Caribbean, China and Australia. Last year, it was spotted in Europe for the first time.
Australia’s first fire ant infestation was in 2001, the ISC said. To date, the country has brought seven infestations under control, from Queensland’s capital, Brisbane, to the border of the neighboring state of New South Wales (NSW), it said, adding that the goal is to contain the infestations and then eradicate them.
But in November 2023, the ants were detected in NSW, sparking concern that they could reach the Murray-Darling river basin and spread out of control.
At the time, NSW’s Minister for Agriculture, Tara Moriarty, reiterated that “red imported fire ants are a terrible invasive pest, which cause serious social, economic and environmental harm.”
“Our teams are focused on limiting further spread, and encouraging reporting and compliance through a targeted communications campaign,” she added.
Red ants can spread quickly on their own, but an infestation is typically accelerated by human activity, such as in cargo containers or shipments of potted plants or soil.
