https://www.wettropics.gov.au/

The Wet Tropics Management Authority established the Yellow Crazy Ant Eradication Program (the Eradication Program) in 2013, with the aim to eradicate these invasive ants from the Wet Tropics World Heritage Area (the Area) and surrounding region. The Eradication Program helps fulfil Australia’s World Heritage Convention obligations by protecting the Area’s unique biodiversity and Outstanding Universal Value.

Yellow crazy ants (Anoplolepis gracilipes) are among the world’s 100 worst invasive species, posing serious threats to the environment, native wildlife, agriculture and our way of life.

Native to Southeast Asia, yellow crazy ants have spread globally through international trade and shipping. They were first detected in Cairns in 2001 and Kuranda in 2014.

  • Close-up of a golden ant standing on a green leaf covered with water droplets.
    © WTMA/Alan Henderson

    Yellow crazy ants (Anoplolepis gracilipes) are among the world’s 100 worst invasive species, posing serious threats to the environment, native wildlife, agriculture and our way of life.

  • A pyramid shaped mountain rises above rainforest and farmland.
    © WTMA

    Native to Southeast Asia, yellow crazy ants have spread globally through international trade and shipping. They were first detected in Cairns in 2001 and Kuranda in 2014.

WTMA’s success

WTMA’s success relies on strong leadership, science-driven management, and active community, industry, and landholder support. This approach has delivered the largest eradication of yellow crazy ants in the world.

WTMA's Eradication Program is jointly funded by the Australian and Queensland governments. An independent review in June 2025 confirmed that eradication remains technically feasible, in the national interest, and achievable with continued funding. The cost of eradication is small compared to the potential environmental and economic damage these ants could cause.

The impact of yellow crazy ants

  • Green praying mantis on a leaf being swarmed and consumed by a colony of small yellow ants.
    © WTMA

    Environment

    Yellow crazy ants can devastate ecosystems by:

    • preying on native wildlife such as reptiles, frogs, birds, and insects
    • reducing species diversity and outcompeting native ants
    • displacing larger animals like mammals due to their acid-spraying behaviour.
  • Alt text Four field staff members in a line searching grassland with rainforest hills behind.
    © WTMA

    Agriculture

    In dense infestations, yellow crazy ants:

    • reduce crop yields by farming scale insects, which damage plants and promote sooty mould
    • impact farmers’ revenues, particularly in sugarcane and other crops.
  • Dusk view from a lookout over a forested valley to distant mountains and farmland.
    © WTMA

    Lifestyle

    Yellow crazy ants affect daily life by:

    • spraying formic acid at humans, pets and other perceived threats
    • infesting homes and damaging electrical equipment.

Protecting the Wet Tropics

Farmer cleaning dust from a large green sugarcane harvester in a field near forest edge.
© WTMA
Farmer cleaning sugarcane harvester

Yellow crazy ants threaten the unique biodiversity of the Wet Tropics World Heritage Area, the Great Barrier Reef’s island national parks, and threaten the Cairns tourism industry, which supports one in six jobs.

The cost of eradication is a small price to pay to safeguard the region’s environment, economy and lifestyle.

Learn more

  • Two yellow crazy ant handbook covers, one for Business and Industry, one general community guide.
    © WTMA

    Handbooks

    Read our handbooks to discover more about yellow crazy ants, their impacts and how you can help.

  • Graphic with report card cover image and next page
    © WTMA

    Report card

    Stay informed on WTMA's progress with the Eradication Program report card.

Last updated: 13 Oct 2026