Little Fire Ant, Wasmannia auropunctata: Distribution, Impact and Control

• Published in: Sociobiology (Chico, CA) Vol. 41; no. 3; pp. 1 - 41
• Main Authors: Wetterer, J.K, Porter, S.D
• Format: Journal Article
• Language: English
• Published: 2003
• Subjects: ecological impact; exotic pests; fire ant control; fire ants; geographical distribution; insect control; insect ecology; insect pests; literature reviews; pest ants; Wasmannia
• ISSN: 0361-6525; 2447-8067

The little fire ant, Wasmannia auropunctata, has been increasing in importance as an exotic pest. Here we review published and unpublished information on its distribution, ecology, impact, and control. Wasmannia auropunctata occurs throughout most of the warmer parts of the New World, from subtropical Argentina to subtropical Mexico and through much of the Caribbean, though it is not clear whether this species is native to this entire region. During the past century, exotic populations of W. auropunctata have become established in numerous other places, including the Galapagos Islands, West Africa (Gabon, Cameroon, and possibly the Republic of Congo and the Democratic Republic of Congo), Melanesia (New Caledonia, Solomon Islands, Vanuatu, and possibly Tuvalu), Polynesia (Wallis and Futuna and Hawaii), the mainland US (Florida and possibly California), and on subtropical Atlantic islands (the Bahamas and Bermuda). The latitudinal range of known outdoors populations of W. auropunctata is from 32o40'S in Argentina to 32o20'N in Bermuda. Wasmannia auropunctata is also a greenhouse pest in more temperate regions, such as England and Canada. In many areas, W. auropunctata can be a significant agricultural pest, not only stinging agricultural workers, but also enhancing populations of Homoptera. Homoptera cause damage both through sapping plants of nutrients and by increasing the occurrence of diseases, including viral and fungal infections. In addition, W. auropunctata has negative impacts on many animals, both invertebrates and vertebrates, though most reports on such impact have been anecdotal. The impacts of W. auropunctata populations seem to be most severe on tropical islands where it is not native, such as the Galapagos, New Caledonia, and the Solomon Islands. Reports of widespread blindness in both domestic and native mammals caused by W. auropunctata stings deserve serious attention. Chemical control of W. auropunctata may be possible for small exotic populations spread over a few dozen hectares or less. For large exotic infestations, the only hope for long-term control appears to be classical biocontrol.