A significant fire ant outbreak has been confirmed at the BHP Broadmeadow coal mine in Queensland, about 150km inland from Mackay.

Officers from the National Fire Ant Eradication Program (NFAEP) visited the site in Moranbah on July 9 and destroyed the nest using direct nest injection. The team is now investigating how the invasive ants reached the remote location.

The NFAEP is working closely with BHP Mitsubishi Alliance to contain, treat, and eradicate the infestation. The Invasive Species Council has described the breach into the coal mine as “unacceptable.”

Red imported fire ants, originally from South America, have been spreading across Queensland and survived recent flooding by forming “rafts” with their bodies to float, allowing them to travel during Cyclone Alfred.

Experts warn that the ants may have hitched rides on vehicles, unknowingly transported to new areas by private and commercial drivers.

Amanda Lintott, director of Autonomy, said that entire colonies have been seen clinging to debris after the floods, ready to nest on dry land, posing a major threat to other parts of Australia.

Fire ants can swarm in seconds and deliver painful, burning stings. While most bites are treatable with cold compresses and antihistamines, severe allergic reactions may require immediate medical attention.

The invasive species was first detected in Brisbane in 2001, likely entering Australia via shipping containers. Despite their small size—just 2 to 6 millimetres—they pose enormous environmental, economic, and public health risks.

Reece Pianta of the Invasive Species Council said unchecked fire ant spread could result in greater economic damage than all of Australia’s other invasive species combined.

Currently, fire ants are only known to be in south-east Queensland, with isolated detections in northern New South Wales that were successfully eradicated.

Authorities urge the public to report sightings of fire ants or their nests by calling 132 ANT (13 22 68) or reporting online.