Biodiversity and Conservation

, Volume 20, Issue 13, pp 3267–3278 | Cite as

Eradication of populations of an invasive ant in northern Australia: successes, failures and lessons for management

  • Benjamin D. Hoffmann
Original Paper


Eradication is the most difficult management goal for exotic species, and successes are rare and even more rarely published. The lack of publication of the methodology and outcomes of eradication programs severely limits the transfer of knowledge to programs elsewhere that target the same or similar species. Here I detail the successes and failures of eradication efforts on six populations of African big headed ant Pheidole megacephala in northern Australia, covering a combined area of almost 9 ha. Two years post-treatment, assessment criteria for successful eradication were met for four of the six populations, whereas eradication failed in the remaining two, resulting in the need for ongoing management. Positive outcomes are attributed to eight criteria being met: (1) a single line of project management authority; (2) over-arching legal authority; (3) susceptibility of the target organism to control procedures; (4) sufficient resources; (5) detectibility of the target organism at low densities; (6) early intervention; (7) prevention of reinvasion; and (8) prevention of invasive succession. Reasons for one of the failures remain unclear, but eradication failed in the other because a part of the population was not treated. In both cases, the eradication failures could have been detected and managed much earlier than was the case. The successes and lessons documented here, coupled with the now large number of small-scale eradications of this ant, warrant the implementation of larger and more ambitious management programs against this significant invader, especially within areas of high conservation value.


Exotic Invertebrate Management Pheidole megacephala Tramp ant Treatment 



I thank Dhimurru Aboriginal Corporation, particularly D. Lacey and A. Pearson, for conducting the project. Field assistance was provided by J. Edgar and many people involved in Conservation Volunteers Australia. M. Gruber created Fig. 1. Funding was provided by the Northern Territory Regional Investment Strategy through the Natural Resources Management Board of the Northern Territory to conduct on-ground works, but not to write this publication of project outcomes. Comments by A. Andersen and A. Grice improved the manuscript.


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Copyright information

© Springer Science+Business Media B.V. 2011

Authors and Affiliations

  1. 1.CSIRO Ecosystem Sciences, Tropical Ecosystems Research Centre, PMB 44WinnellieAustralia

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