Fire ant nest found and destroyed at Sydney's Enfield logistics centre

A red imported fire ant nest was discovered and destroyed at the Enfield Intermodal Logistics Centre in Sydney's inner west, the New South Wales government said on 13 October. Federal biosecurity officers first detected the ants in a lure used to detect and monitor invasive species, after which a nest was found and treated at the freight logistics and warehousing facility.abc.net.au

The detection matters because fire ants are one of the world's worst invasive species, able to sting people and livestock and cause serious harm to the environment and local economies. What is new is that genetic analysis confirmed the ants likely arrived from overseas via a container rather than spreading from the established infestation in south-east Queensland, meaning a separate introduction had to be intercepted.smh.com.au

How the nest was found

Specialist fire ant detection dog teams undertook surveillance at the Enfield Intermodal Logistics Centre and in the immediate vicinity, and no other nests were found at the site. An incident management team was established, including experts from the NSW Department of Primary Industries and Regional Development and Queensland-based officers from the National Fire Ant Program.

The ants are 2 to 6 millimetres long, dark red-brown in colour, and live in nests in the ground. Their sting causes a painful, fire-like burning sensation and leads to swelling and redness that can develop itchy blisters or pustules taking days to improve, according to the NSW government's description of the species.afr.com

Genetic tests confirmed the fire ants were likely to have originated from overseas via a container and not from south-east Queensland, where Australia's main fire ant infestation sits. The nest was destroyed after the initial detection in the lure used by Commonwealth Department of Agriculture, Fisheries and Forestry officials at the Strathfield South site.theguardian.com

Where the ants came from

The NSW government said it would work with the local community to raise awareness in coming days so people could be on the lookout. Local businesses dealing in soil, turf, building materials or vegetation would be contacted to identify and treat any incursion while minimising disruption, Agriculture Minister Tara Moriarty said.

The immediate focus is inspecting and treating any potential location within a 500-metre radius of the Intermodal Centre, then surveillance and treatment in the surrounding 2-kilometre radius. The government said these distances are based on scientific understanding of how queen fire ants can move and potentially establish a new nest.

The treatment radius explained

Biosecurity teams successfully eradicated fire ant nest incursions in NSW's Northern Rivers over the last three years and at Port Botany in 2014, the NSW government said. Invasive Species Council advocacy director Reece Pianta said biosecurity measures found the insects before they had the chance to become an established infestation.

The Invasive Species Council describes fire ants as one of the world's worst super-pests, which if established and spread around Australia would cost the economy up to $2 billion a year. Pianta said the detection was a reminder of why investment in border biosecurity was so important, and called for more funding for the national eradication program.

In south-east Queensland, fire ants invade backyards, parks and sporting fields, attack pets and wildlife and threaten agriculture and infrastructure, Pianta said, adding that Sydney does not want to find out what living with fire ants looks like. Moriarty said no further ants had been found but the state was focused on identifying and eradicating any potential spread quickly.

The NSW government said it would continue surveillance and treatment where required in the surrounding 2-kilometre radius, with awareness campaigns for nearby residents and businesses in coming days so they could report sightings. Moriarty said while fire ants are one of the world's most invasive species, they can and have been successfully eradicated in NSW, pointing to the Northern Rivers incursions over the last three years and the Port Botany incursion in 2014 as precedents for the response now under way at Enfield.