Browsing ants

​​​​​​​​​Browsing ant in the Northern Territory


Activities to contain and control browsing ants (Lepisiota frauenfeldi) are continuing in Darwin, in the Northern Territory (NT).  Most of the properties where there are infestations are within the vicinity of the Darwin seaport, and at the Berrimah industrial estate.

The Northern Territory Department of Primary Industry and Resources is continuing with its tracing and surveillance activities to determine the spread of these ants.  Tracing activities involve the use of specifically trained odour detection dogs.

The browsing ant populations that have been located are being treated through an ongoing baiting and spraying program. 

Browsing ants are exotic to Australia and were first detected in 2013 in Perth, Western Australia (WA) followed by the detection at the Darwin seaport in July 2015. In the absence of genetic analysis capabilities at this time, the WA and NT detections are not considered to be directly linked to each other. The eradication efforts to date have prevented browsing ant from establishing in Australia, however these ants remain a threat to our environment with the potential to invade our backyards, and damage plants and landscaping.  They do not harm people or pets.

The National Biosecurity Management Consultative Committee (NBMCC) continues to meet and discuss the technical aspects of this response, including reviewing the agreed national response plan.  The committee agrees that it is technically feasible and cost beneficial to eradicate browsing ant from Australia.  In January 2018, the National Biosecurity Management Group provided a commitment of $4.6 million to eradicate this invasive pest from the Northern Territory by mid-2021 under the National Environmental Biosecurity Response Agreement (NEBRA). This agreement supersedes the original response plan as browsing ant was detected on more properties in Darwin than initially budgeted for. The response plan going forward has estimated sufficient resources to achieve eradication at the projected number of infested premises.

About browsing ants

Browsing ants are a slender ant, and are a consistent shiny dark brown in colour. They are 3–4mm in length with long antennae and long legs, and run about in a crazy or haphazard manner when disturbed. 

They form super-colonies, reaching large numbers and will be noticeable on the ground as well as in trees, leaf litter and infrastructure such as electrical boxes. They farm and protect scale insects which can eventually kill the plants they live on, and they eat and displace native ant species as well as other insects.  Although the immediate impacts of browsing ant are considered to be environmental, the species’ ability to farm scale insects and the subsequent effects on plant health, indicates risk to agriculture and horticulture and are therefore of national significance.

Browsing ants are commonly found in South East Asia including Timor Leste and Malaysia.

They form part of a group referred to as Tramp Ants.

What you need to do

It is important that people working around Darwin - at the port, in industrial areas, and people who transport goods out of these areas, are vigilant for these ants and report them if they see any suspect sightings. 

Ants can hitchhike their way out of the area on goods and vehicles. In particular, they can be moved with shipping containers and cargo, as well as in soil, mulch, fertiliser and other plant material.  

Before leaving any site where ants are present, check that they aren't in your consignment, and haven't crawled onto vehicles, equipment or clothing.

The movement restrictions mandated at infested sites must be adhered to so these ants are not inadvertently moved out of the area or interstate. 

On 6 August 2015, browsing ant was gazetted as a pest and made notifiable under the Northern Territory Plant Health Act.

If you think you've found a browsing ant population, you must report it to the Exotic Plant Pest Hotline on 1800 084 881 as soon as possible.​

Image of browsing ant

Image of browsing ants on hand

Photos courtesy of the Department of Agriculture and Food Western Australia

Browsing ant in Western Australia

The first known Australian detection was at Perth Airport in 2013 followed by detection at a commercial property near the airport at Belmont, Western Australia in August 2014. The Commonwealth and Western Australian governments worked together to respond to these incursions, which have subsequently been officially eradicated.

In February 2017 Browsing ants were detected at a property in Welshpool, and in July  2017 at Kewdale. The Western Australian Government is continuing surveillance and treatment activities for these detections, while the NBMCC continues to provide technical advice and to consider whether a national eradication response is required.

More information

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