Skip to main content Skip to main navigation Skip to search

Queensland and NSW floods 2022

Visit recovery.gov.au to see what help is available.

Close
Home

Top navigation main

  • News & media
  • Jobs
  • Ministers
  • Contact us
Main menu

AWE Main

  • Climate change
    Climate change Driving climate action, science and innovation so we are ready for the future.
    • Climate science and adaptation
    • Australia's climate change strategies
    • Emissions reduction
    • Emissions reporting
    • International commitments
    • Climate Active
    • Climate change publications and data
    • Australia’s National Greenhouse Accounts (Emissions Data)
    Stronger action on climate change

    Stronger action on climate change

    See how the Australian Government is committed to taking more ambitious action on climate change.

    Find out more

  • Energy
    Energy Building a secure and sustainable energy system for all Australians.
    • Energy policy in Australia
    • Energy ministers
    • Renewable energy
    • Energy publications
    • energy.gov.au
    • Energy Rating
    • Commercial Building Disclosure Program
    • Nationwide House Energy Rating Scheme (NatHERS)
    • Your Home
    Decorative image

    Australian Energy Employment Report survey

    Share insights to help the energy workforce plan for the future

    Find out more

  • Environment
    Environment Improving stewardship and sustainable management of Australia’s environment.
    • Bushfire recovery
    • Climate change and the environment
    • Biodiversity
    • EPBC Act
    • Environmental information and data
    • International activities
    • Invasive species
    • Land
    • Marine
    • Partnerships
    • Protection
    • Report a breach of environment law
    • Threatened species & ecological communities
    • Waste and recycling
    • Wildlife trade
    Decorative image

    Read our Nature Positive Plan

    Our plan sets out the Australian Government’s commitment to environmental law reform

    Find out more

  • Water
    Water Improving the sustainable management of Australia’s water supply for industry, the environment and communities.
    • Coal, Coal seam gas (CSG) and water
    • Commonwealth Environmental Water Office
    • Water policy and resources
    • Wetlands
    Water matters

    Water Matters

    Keep up with the latest news on the department's work in managing Australia's water resources.

    Read the latest edition here

  • Parks and heritage
    Parks and heritage Managing Australia’s iconic national parks, historic places and living landscapes.
    • Australian Marine Parks
    • Australian National Botanic Gardens
    • Booderee National Park
    • Kakadu National Park
    • Christmas Island National Park
    • National parks
    • Norfolk Island National Park
    • Heritage
    • Pulu Keeling National Park
    • The Great Barrier Reef
    • Uluṟu-Kata Tjuṯa National Park
    The reef

    Great Barrier Reef

    Australia is protecting and conserving this World Heritage Area.

    Find out more

  • Science and research
    Science and research Undertaking research and collecting data to support informed decisions and policies.
    • Climate change
    • Australia's biological resources
    • National Environmental Science Program (NESP)
    • Our science strategy
    • Australian Biological Resource Study (ABRS)
    • State of the Environment (SoE) reporting
    • Bird and bat banding
    • Supervising Scientist
    Our climate is changing

    Our climate is changing

    Find out more about how climate science helps Australians with the impacts of climate change.

    Find out more

  • About us
    About us We lead Australia’s response to climate change and sustainable energy use, and protect our environment, heritage and water.
    • Accountability and reporting
    • Assistance, grants and tenders
    • Fees and charges
    • News and media
    • Our commitment to you
    • People and jobs
    • Publications
    • What we do
    • Who we are
    Decorative image

    Juukan Gorge response

    Read the Australian Government's response to the destruction at Juukan Gorge and the recommendations

    Read the response

  • Online services
    Online services We do business with you using online platforms. This makes it easier for you to meet your legal requirements.
Department of Climate Change, Energy, Enviroment and Water

Breadcrumb

  1. Home
  2. Parks and heritage
  3. National Parks
  4. Welcome to Christmas Island National Park
  5. Christmas Island Publications
  6. Crazy ant biocontrol | Christmas Island National Park

Sidebar first - EN - National parks

  • Christmas Island National Park
    • Culture and history
    • Natural environment
      • Geology
      • Habitats
      • Native animals
      • Marine life
      • Plants
    • Management and conservation
      • Park management
      • Conservation projects
      • Expert Working Group
    • Permits, licences and leases
      • For media and artists
      • For tourism operators
      • For events and other commercial activities
      • For other activities
      • For researchers
      • For long-term use of a site to conduct an activity
    • Publications
    • Media Centre

Crazy ant biocontrol | Christmas Island National Park

Parks Australia

Department of Agriculture and Water Resources Risk Analysis

On 24 September 2015, the Department of Agriculture and Water Resources published a final risk analysis, concerning the proposed release of Tachardiaephagus somervillei for the control of the invasive scale insect Tachardina aurantiaca on Christmas Island.

The relevant project documentation is below.

Application - Christmas Island biocontrol project (PDF - 1.84 MB)

Supporting documentation - Christmas Island biocontrol project (PDF - 3.49 MB)

To view the final risk analysis, visit  http://www.agriculture.gov.au/biosecurity/risk-analysis/reviews/biological-control-agents/risk-analyses/completed-risk-analyses.

On Christmas Island, Parks Australia and La Trobe University have worked towards a new way of controlling invasive yellow crazy ants, by using indirect biological control (also called ‘biocontrol’). This means using another insect to target the crazy ants’ food source, as a way of cutting down their numbers and stop them causing so much environmental damage, especially to iconic red crab populations. In this case, the biological control agent that we want to use is a tiny insect called a micro-wasp.

The success of this project should reduce the need for poison baiting to control the ants. Poison baiting is expensive, short term and unpopular with local residents, but it has been the only available and feasible option control the ants.

Micro-wasps are already used for biological control on mainland Australia, so this approach is fairly common. We’re a long way from the days of the cane toad, which was released in Australia with very little scientific testing. These days biological control is carefully planned and controlled.

  • Factsheet - Biocontrol of crazy ants on Christmas Island (PDF - 231.14 KB) | (DOCX - 1.48 MB)

How the ‘biocontrol’ project will work

A tiny Malaysian insect called a micro-wasp will be brought onto Christmas Island by scientists from La Trobe University. It is 2 mm long and its formal name is Tachardiaephagus somervillei.

The micro-wasp doesn’t sting or build nests and it doesn’t harm humans, native wildlife or horticulture. Many similar micro-wasps already live on the island, but are rarely noticed.

Scientific studies indicate this biocontrol micro-wasp will stop crazy ants by cutting down their food supply, honey dew, which is produced by another non-native species, the yellow lac scale insect. The micro-wasp kills the lac scale insect by laying eggs inside it. The micro-wasp is extremely ‘host-specific’. This means it only preys on one thing – the particular species of lac scale insect on Christmas Island – so it doesn’t harm anything else.

There are already strict quarantine protections in place which prevent insects from reaching the Australian mainland from Christmas Island. Parks Australia, which manages Christmas Island National Park, is funding the project and is jointly managing it with La Trobe University. Rangers and scientists will rear the micro-wasps and then release them into ‘super-colonies’ of crazy ants. The results will be carefully monitored to see how the crazy ants react to a reduction in their food supply.

Over time, we hope to see crazy ant numbers fall so much that they no longer form destructive ‘super-colonies’ made of billions of ants, which are causing so much damage.

The crazy ant problem

Crazy ants are an introduced species that are hugely destructive to the environment on the island. Over recent decades, they have killed tens of millions of Christmas Island’s iconic red crabs.

Until now, the only way to stop crazy ants wiping out Christmas Island’s wildlife was to use poison bait. Rangers from Christmas Island National Park have to lay the bait in the dense ‘super colonies’ that swarm with billions of crazy ants, using a mix of hand delivery and aerial baiting from a helicopter.

While this baiting is effective it is only a temporary solution. The crazy ants move back in from remote and inaccessible parts of the island, and within a few years more baiting is needed. This is expensive, labour intensive and the use of poison is unpopular amongst local residents.

Parks Australia and Christmas Island National Park have been working on a better solution. Since 2009, Parks Australia have partnered with La Trobe University to investigate the use of a ‘biological control agent’ – to work out if there were any animals that could help us control the crazy ants without having any negative impacts on Christmas Island or its environment.

The scientists are confident this micro-wasp biocontrol solution will be safe and effective on Christmas Island.

Assessment by the Department of Agriculture and Water Resources

The Australian Government Department of Agriculture and Water Resources has carried out a risk analysis for the release of Tachardiaephagus somervillei on Christmas Island for the control of the invasive scale insect Tachardina aurantiaca.

The final risk analysis was released for public comment on 24 September 2015. The final risk analysis report recommends release of Tachardiaephagus somervillei on Christmas Island.

The final risk analysis will inform a decision by the Department of the Environment on whether to recommend that the Minister add the control agent to the list of approved live imports.

Assessment by the Department of the Environment

The Australian Government Department of Agriculture and Water Resources has carried out a risk analysis for the release of Tachardiaephagus somervillei on Christmas Island for the control of the invasive scale insect Tachardina aurantiaca.

After a thorough risk analysis the Department of the Environment and Energy recommended that the Minister add the control agent to the list of approved live imports.

Read more on the Department of the Environment assessment process

  • Factsheet - Biocontrol of crazy ants on Christmas Island (PDF - 231.14 KB) | (DOCX - 1.48 MB)
  • Brochure – Detail of biocontrol project on Christmas Island (PDF - 2.83 MB)
  • Public notice (PDF - 71.72 KB)
  • Summary of Public Comments (PDF - 13.08 KB)
  • Preliminary documentation (PDF - 4.28 MB) (contains the following documents)
    • Preliminary Documentation: response to additional information request
    • Attachment 1: Host specificity testing of Tachardiaephagus somervillei (Hymenoptera: 1 Encyrtidae), a biological control agent for the yellow lac scale 2 Tachardina aurantiaca (Hemiptera: Kerriidae)
    • Attachment 2: Comments and suggestions for host specificity testing protocol (Neumann et al. 2013) from 5 ad hoc reviewers
    • Attachment 3: Research and development of biological control for scale insects: indirect control of the Yellow Crazy Ant on Christmas Island, 2009‐2013
    • Attachment 4: Christmas Island and Pulu Keeling National Parks Crazy Ant Scientific Advisory Panel (CASAP) Terms of Reference
    • Attachment 5: CASAP Minutes from 12th December 2012 (CI time 10:00am to 1.00pm)
  • EPBC Referral Documents 2013/6836 (PDF - 4.26 MB)  (contains the following documents)
    • ‘Importation, rearing and release of Tachardiaephagus somervillei (Hymenoptera: Encyrtidae) as a biological control agent for the yellow lac scale Tachardina aurantiaca (Hemiptera: Kerriidae) on Christmas Island, Indian Ocean’ and attachments, dated 19 April 2013.
    • Amendments to Referral number 2013/6836 and attachments, dated 2 May 2013.

Please download Adobe reader if you are unable to view the PDF documentation.

 
Thanks for your feedback.
Thanks! Your feedback has been submitted.

We aren't able to respond to your individual comments or questions.
To contact us directly phone us or submit an online inquiry

CAPTCHA
This question is for testing whether or not you are a human visitor and to prevent automated spam submissions.

Please verify that you are not a robot.

Skip

Footer

  • Contact us
  • Accessibility
  • Disclaimer
  • Privacy
  • FOI
Last updated: 03 October 2021

© Department of Climate Change, Energy, the Environment and Water

We acknowledge the Traditional Owners of country throughout Australia and recognise their continuing connection to land, waters and culture. We pay our respects to their Elders past, present and emerging.