Exotic invasive ants

24 January, 2017

The Plant Biosecurity CRC is involved with stakeholders around the country in tackling the problem of exotic invasive ants. Here is an overview about the problem in Australia.

The invasive ant problem

Exotic invasive ants are an environmental and social amenity pest with the potential to cause significant negative impacts on Australia’s unique biodiversity and to human health. Australia’s National Biosecurity Committee has identified exotic invasive ants as high priority, and they have been placed on the national priority pest list endorsed by the Plant Health Committee.

There are many types of exotic invasive ant species which have been detected in Australia. Those that are of most concern include:

• Yellow crazy ant (Anoplolepis gracilipes)
• Tropical fire ant (Solenopsis geminata)
• Electric ant (Wasmannia auropunctata)
• Argentine ant (Linepithema humile)
• African Big-Headed ant (Pheidole megacephala)
• Red imported fire ant (Solenopsis invicta)
• Browsing ant (Lepisiota frauenfeldi)

These ants can transform ecosystems, deplete insect life from an area and even kill small animals. Economically invasive ants can compromise eco-tourism and recreation, reduce crop yields and lead to the death of farm animals. The economic costs associated with control programs are substantial – the national cost of the red imported fire ant control program in Queensland has amounted to almost $330 million over a 16 year period.

Red imported fire ants attack ground-nesting bird chicks as they try to peck their way out of their eggs. Photo credit: Brad Dabbert, www.bugmugs.org

A dead gecko being dragged away by yellow crazy ants. Photo credit: Dinakarr (CC0), via Wikimedia

Management

The entry pathways for exotic invasive ants include sea and air cargo, imported machinery, shipping containers, nursery stock imports, international mail, imported scrap metal and air passenger baggage; however there are activities being undertaken to minimise the risk of incursions and to review current border control measures.

There are now eight separate exotic invasive ant eradication programs underway in Australia. Yellow crazy ant is considered established in Australia, and so not able to be eradicated, and is managed by the Australian Government Department of the Environment and Energy.

National plan

The National Biosecurity Committee has agreed to the development of a national plan to prevent, prepare and respond to exotic invasive ant incursions and detections. This includes the establishment of a national surveillance program.

Achieving this requires the development of a comprehensive research, development and extension plan to identify and address gaps in research needs. Additionally, the plan will support decisions around allocation of resources for effective exotic invasive ant surveillance operations and the development of risk-based approach to surveillance.

Ant specialists from agriculture and environment agencies, researchers, international experts and the Invasive Species Council met in November 2016. This workshop was the first meeting of Australian and international experts to develop a national Tramp Ant Biosecurity Plan and to identify key research needs for national surveillance activities.

The workshop was organised by the Plant Biosecurity CRC on behalf of the Australian Government Department of Agriculture and Water Resources in response to the increasing number, currently eight, of emergency response plans underway for exotic invasive ants.

The next step will be the compilation and analysis of the outputs from the workshop to be used in the development of a draft national biosecurity plan for exotic invasive ants. The draft plan will be considered by the National Biosecurity Committee in early 2017.

You can read the communique from the workshop here.

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The item above came from the CRC on Biosecurity.

This is very relevant across northern Australia, including many urban areas.  Vigilance in managing ants is vital.

However, while there are some excellent products available to really knock over colonies of ants through accumulation of insecticides in the nest, so many homeowners and property managers do not take that step to actually do it. The process is relatively easy and small amounts of insecticides do a great job.

Watch out for denuded areas, often a sure sign of established colonies - in urban areas it can be denuded areas of turf / grass.  Closer inspection usually shows ant access spots or nests.  Then add modest amounts of suitable ant bait.  And watch for more!