Activities to contain and control browsing ants (Lepisiota frauenfeldi) are still underway in Darwin, in the Northern Territory. The ants have been found on adjoining properties within the vicinity of the Darwin seaport, as well as a recent detection at an industrial site in Berrimah.
The Northern Territory Department of Primary Industry and Resources is undertaking tracing and surveillance activities to determine the spread of these ants that were first detected at the Darwin seaport in July 2015.
The browsing ant populations that have been located are being treated through an ongoing baiting and spraying program.
Browsing ants are exotic to Australia. They have not established here but 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 Tramp Ant Consultative Committee continues to meet and discuss the technical aspects of this response, including reviewing the agreed national response plan.
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.
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.
Photos courtesy of the Department of Agriculture and Food Western Australia
Previous incursion in Western Australia
Browsing ants have been found in Australia previously. 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 are working together to ensure eradication has been achieved.
So far, the response to browsing ant in Western Australia has been a success with the airport infestation having been fully eradicated. At the Belmont site, no browsing ants have been found between 2015 and 2016 and confirmation of eradication from this site is on track to be declared in early 2017. Declaring freedom from browsing ant will involve the use of odour detection dogs that are specifically trained to detect browsing ants.
Western Australia's eradication activities are being used to inform the response to the current incident in Darwin.