Early Detection and Rapid Response

Prevention is always better than cure, but even the best biosecurity measures cannot stop all invasive species from entering. Early detection and rapid response (EDRR) is the best-proven way to find and eradicate invasive species in a specific location before they establish and spread. EDRR involves undertaking set of processes that define the requirements to effectively respond to an invasive species threat as soon as possible after arrival.

The key to EDRR is to estimate which species are most likely to arrive, and have all the tools in place just in case they do. This is a little like an insurance policy - you hope you never need it but are prepared in case the worst situation arises.

Red imported fire ant (© Alex Wild)

EDRR and the invasion curve : Risk analysis : Surveillance : Be prepared - have everything ready to go now! : What is needed for an ant EDRR?

The invasion curve (image: Harvey and Mazzotti, 2018, The invasion curve: a tool for understanding invasive species management in South Florida, WEC347, UF/IFAS, adapted from Invasive Plants and Animals Policy Framework, State of Victoria, Department of Primary Industries, 2010).

EDRR and the invasion curve

The earlier an invasive species is found, the more likely it is to be successfully eradicated. The invasion curve figure on the left is a good way to visualize why this is.

The figure on the left shows how as an invasive species spreads over time, infesting an increasingly large area, eradication becomes less likely (or even impossible).

At the same time control costs increase dramatically.

The large blue arrow indicates when the species is typically detected and a management response begun. 

The goal of EDRR is to move that blue arrow to an earlier point in time, while eradication is still a likely outcome.

The blue arrow in the figure on the right shows the goal of EDRR - moving the response point to as soon as possible after arrival.

To be able to do this, the major components of EDRR planning are risk analysis, surveillance, and having the tools you need ready. 

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The goal of EDRR is to move the detection and response point to earlier in the invasion curve (image: Harvey and Mazzotti, 2018, The invasion curve: a tool for understanding invasive species management in South Florida, WEC347, UF/IFAS, adapted from Invasive Plants and Animals Policy Framework, State of Victoria, Department of Primary Industries, 2010)

Risk analysis

The first step is to identify which species should be the target of an EDRR strategy. The number of species targeted will be limited by funding, training capacity, tool availability etc.

Having everything prepared for an invader arrival is costly, so while it might be tempting to try to target all potential invaders, it makes more sense to prioritise those invaders that are most likely to arrive and have the biggest impact, i.e., high-risk species.

These high-risk species are those that are already present in trading partners and / or are already present on other islands in country and pose a serious risk elsewhere. The harm these species could cause if they become established is also an important consideration. Risk analyses will help narrow down target species.

In the case of ants in the Pacific, we strongly recommend having EDRR plans for little fire ant and red imported fire ant in place. Little fire ants are already established in several Pacific nations, where they have had devastating impacts on people’s ways of life. Red imported fire ants are present in potential trading partners like Australia, Japan and South Korea. They are known to cause serious harm where they occur.

Kiribati's Ministry of Environment Lands and Agricultural Development (MELAD) and partners have recently developed an EDRR plan and work is underway implementing EDRR for little fire ants and red imported fire ants in the Port of Betio, in Tarawa.

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Little fire ants (© Alex Wild)


Early detection depends on regular surveillance!

Active surveillance should be undertaken regularly by biosecurity personnel in high-risk areas such as ports and other possible points of entry (identified during the risk analysis). Active surveillance involves going out and looking for the target species. For ants, this usually involves using attractive lures, pitfall traps and visual surveys.

It is also essential that the biosecurity team be trained to identify the target species, and know what to do if that species is found. Reporting the pest as soon as it is detected is critical for success. All team members should know who to report to.

Passive surveillance uses the community to find possible problem species. This relies on people being aware of what the invasive species looks like, the problems they cause and having a way to inform authorities. This is a good way to catch secondary invasion points. An awareness campaign is the best way to encourage the community to be involved in battling invasive species.

Be prepared - have everything ready to go now!

The key to rapid response is having everything necessary to respond to an ant incursion ready to go BEFORE the incursion happens!

This will involve:

  • Identifying risk points (arrival entry points and unloading facilities). This will help to decide on the area that the response plan will need to cover and the type of environment that needs to be treated. For example, for ants, the treatment approach for natural areas will differ from the treatment for inhabited areas.
  • Making a response plan. This can be as complex or as simple as you need. Preferably this will be fully documented, but the main thing is that the key elements are covered. For example, the plan primarily needs to cover:
    • Assigning roles, planning clear lines of communication, looking at what resources are available.
    • Deciding on an appropriate treatment product for the target species (choosing a treatment option). Remember to include provision for tools for applying the product (e.g., manual spreaders and measuring jugs for granular baits or caulking guns for paste baits), and for personal protective equipment (PPE; e.g., gloves)
    • How much will it cost? Estimate costs (including freight).
  • Ordering the treatment product (and any application / PPE tools).
    • find out what permits may be required. Many countries require both an environmental permit or license to use pesticides, and an import permit for getting it into the country. More can be found on environmental legislation here.
    • an environmental impact assessment (EIA) may be needed for the permit. We provide more information on what needs to be included in an EIA in this section.
    • Contact suppliers to order the treatment product(s) and application tools.
  • Provide training in how to use the treatment products for team members.

SPREP's Surveillance and Rapid Response Plan for Priority Invasive Species in Kiribati (download 5.5 MB) provides general surveillance and response guidelines for yellow crazy ant, little fire, red imported fire ant and yellow crazy ant, as well as other high priority non-ant invasive species (i.e. Norway rat and taro beetle). It also details an example draft rapid response plan. 

Remember all these plans need to be completed ahead of time. Start now to be prepared.

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What is needed for an ant EDRR?


  • What treatment product should be used? 

This depends on the preferences of the target ant. However, some products are suitable for multiple species. For example, for Kiribati, red imported fire ants and little fire ants were designated high risk species and targets for EDRR. As the area identified as the highest risk is a port (very little vegetation, not a natural area), a granular bait was considered appropriate. Granular baits have been used to eradicate these species in Australia and the Galapagos. Based on expert advice, Synergy Pro was chosen as a treatment product as the granules are small and both species should be attracted to it, and this was easily sourced from Australia. The approach would likely also be effective for yellow crazy ants. Amdro is another product that could have been chosen, as it is effective on both species. This is available in United States territories.

  • How much treatment product will be needed?

This depends on the size of the target area, the rate of application (kg/ha) and the number of treatment applications required.

  • How long can the bait be stored for (shelf life)?

This depends on the product being used and the storage conditions. Heat and sunlight affect shelf life of all products. Unopened products kept in dark, relatively cool conditions can last several years. The plan needs to include processes for disposal and replenishing the treatment product.

  • Equipment to disperse the treatment products and safety equipment (PPE).

This will depend on the treatment approach chosen, for example, granules.

  • Secure storage facilities for treatment products and equipment.
  • An Environmental Impact Assessment (EIA) or Environmental and Social Impact Assessment ESIA).

Even if an EIA is not required by law, it is always desirable when using pesticides. Considering social implications (ESIA) - how people might be affected by the products used, and by the logistics of treatment - is also very important.

Implementing Kiribati's EDRR programme required an ESIA as part of the application for the environmental license, and was mandated by the funder. Based on expert advice, Synergy Pro was chosen as a treatment product. This product has been effective against both little fire ants and red imported fire ants. Using a single product is a cost-effective approach as it allows a single EDRR plan for two target species. Synergy Pro contains the active ingredients hydramethylnon (a stomach poison) and pyriproxyfen (an insect growth regulator). Download the Kiribati EIA as an example of what an EIA for EDRR needs to consider.

  • How is the treatment product applied?

Use the resources in the PIAT.

Information materials for community handouts

If the EDRR plan needs to be enacted, communication with affected stakeholders is important. Have the following information ready.

  • awareness materials such as posters, leaflets, videos, radio announcements and presentations telling the public what the invader looks like, where it might be found and why people should be worried about it.
  • management materials such as warning posters describing the type of treatment, and when and where it is to be carried out (when and where can be filled in by hand if an incursion occurs). Even though the treatment will only be carried out in the event of an incursion, having these materials ready to go will greatly speed up the time it takes to begin treatment, increasing the chances of success.   


  • Contact information for treatment product suppliers can be found in this table.

If you would like to develop EDRR plans for invasive ants, and require assistance, please contact Pacific Biosecurity, SPREP or an expert in your geographic area.

Information sources

Boudjelas, Froude. 2016. Biosecurity Plan for Ouvea Atoll, Loyalty Islands, New Caledonia. INTEGRE project through SPC and the European Union

Harvey, Mazzotti. 2018. The invasion curve: a tool for understanding invasive species management in South Florida. WEC347, UF/IFAS

Inter-ministry Invasive Species Working Group. 2014. Invasive species early detection and rapid response plan for British Columbia (Canada). Government of British Columbia

Kiribati Government. 2019. Kiribati Biosecurity Emergency Response Programme (draft). 

Pacific Biosecurity. 2018. Environment Licence Application Form. Kiribati Ministry of Environment Lands and Agricultural Development

Pacific Biosecurity. 2018. Environmental and Social Impact Assessment (ESIA) for Early Detection Rapid Response plan for potential incursion of little fire ant and / or red imported fire ant in Tarawa, Kiribati. New Zealand Partnerships for International Development Fund 

Pierce. 2016. A surveillance and rapid response plan for priority invasive species in Kiribati (download 5.5 MB). Report for GEF, UNEP, SPREP, and MELAD (draft)

SPREP. 2016. Catch it early: invasive species early detection and rapid response (download 3.6 MB). Pacific Invasive Species Battler Series

content reviewed by Bradley Meyer, SPREP, September 2018
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