Get access

The diversity and origin of exotic ants arriving in New Zealand via human-mediated dispersal

Authors

  • Darren F. Ward,

    Corresponding author
    1. Tamaki Campus, School of Biological Sciences, University of Auckland, Private Bag 92019, Auckland, New Zealand,
      *Correspondence: Darren Ward, Tamaki Campus, School of Biological Sciences, University of Auckland, Private Bag 92019, Auckland, New Zealand. E-mail: d.ward@auckland.ac.nz
    Search for more papers by this author
  • Jacqueline R. Beggs,

    1. Tamaki Campus, School of Biological Sciences, University of Auckland, Private Bag 92019, Auckland, New Zealand,
    Search for more papers by this author
  • Mick N. Clout,

    1. Tamaki Campus, School of Biological Sciences, University of Auckland, Private Bag 92019, Auckland, New Zealand,
    Search for more papers by this author
  • Richard J. Harris,

    1. Department of Environmental Biology, Curtin University of Technology, PO Box U 1987 Perth 6845, Western Australia, Australia and
    Search for more papers by this author
  • Simon O’Connor

    1. MAF Biosecurity New Zealand, PO Box 2526, Wellington, New Zealand
    Search for more papers by this author

*Correspondence: Darren Ward, Tamaki Campus, School of Biological Sciences, University of Auckland, Private Bag 92019, Auckland, New Zealand. E-mail: d.ward@auckland.ac.nz

ABSTRACT

The number of exotic ant species being dispersed to new regions by human transportation and the trade pathways responsible for this are poorly understood. In this study, the taxonomic diversity, trade pathways, and origin of exotic ants intercepted at the New Zealand border were examined for the period 1955–2005. Overall, there were a total 4355 interception records, with 115 species from 52 genera. The 10 most frequently intercepted genera, and the 20 most frequently intercepted species contributed > 90% of all records. Many of the species frequently intercepted are regarded as invasive species, and several are established in New Zealand. The most intercepted species was Pheidole megacephala. Despite a relatively low trade relationship, a high proportion (> 64%) of the exotic ants which were intercepted originated from the Pacific region. However, the majority of species intercepted from the Pacific was exotic to the region (71%), or to a lesser extent, wide-ranging Pacific native species. No endemic species from the Pacific were intercepted. The effectiveness of detecting exotic ant species at the New Zealand border ranged from 48–78% for different trade pathways, indicating a number of species remain undetected. Trade routes associated with specific geographical regions represent a major filter for the arrival of exotic ant species. Despite the importance of the Pacific as a frequent pathway, we suggest that the future establishment of exotic ant species in New Zealand is likely to be mitigated by a renewed focus on trade routes with cool temperate regions, particularly Australia.

Get access to the full text of this article

Ancillary