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An infestation of the much-dreaded little fire ant, Wasmannia auropunctata, was discovered on a farm in Waihee early last month, the first known such foothold on the island. True to its name, the little fire ant is small, about as long as a penny is thick, with a sting disproportionate to its size. Will Maui residents be able to pull together to effectively address the threat of this invasive species?

As reported in the Oct. 16 Maui News, the Hawaii Department of Agriculture (HDOA) will be working with the Waihee farm owner to eradicate the half-acre infestation. The ant may have been at this site for a year. The painful sting delivered by this tiny pale-orange insect develops into large red welts. Some people are more sensitive to the sting than others.

Many perceive little fire ants as less of a threat than red imported fire ants. Nevertheless, the little fire ant is a very serious pest that can attain high densities, and its powerful sting poses problems for domestic animals, wildlife, agricultural workers and others who come in contact with it. When populations build up outdoors, little fire ants eventually come indoors and sting people in their homes. In this regard this ant is worse than the other "imported fire ants" on the Mainland. Details of the pest threat and how to combat it are summarized nicely in a CTAHR leaflet, available at www.ctahr.hawaii.edu/oc/freepubs/pdf/IP-LFA.pdf

Native to South and Central America, the little fire ant has invaded locations in West Africa; Florida; the Galapagos Islands; several Pacific island nations - New Caledonia, Wallis and Futuna, Solomon Islands, Vanuatu and Tahiti; Israel, and Australia.

Although the little fire ant first was detected in the state on Hawaii island in March 1999, officials believe the pest was there for at least four years before being discovered; a lag between invasion and detection is regarded as "normal." In retrospect, the bug likely had reached Hawaii from Florida; genotypes of Hawaii little fire ants are essentially identical to such specimens from the Lake Placid area of central Florida. As soon as the invasive species was discovered in Puna in 1999, Department of Agriculture staff members realized the seriousness of the situation. They developed a pest advisory and assigned an entomologist to lead appropriate efforts involving detection, experimental efforts at eradication of local populations, and interisland quarantine.

A 2005 review of efforts by Agriculture Department workers to address this serious ant pest suggested they were "hindered by low staffing levels; lack of public and commercial awareness; lack of access to nursery sales records; the difficulty of detecting this ant; lack of a registered ant control product for use in orchard fruit and vegetable crops; the failure of most people to take the threat of its invasion seriously. HDOA demurred from an all-out eradication effort and enactment of an intraisland quarantine to prevent infected nurseries from selling plants."

The fact that some plant nurseries were infested and probably selling infested plants made containment virtually impossible. By September 1999, the little fire ant was known to occupy 30 acres in three populations. By January 2004, officials identified 31 populations infesting a total of nearly 200 acres. Eight of those populations involved nursery infestations, and the nurseries still were selling plants. The invading bug currently is coalescing in Hilo and Puna, much like coqui frogs.

Maui officials are determined to keep this ant out. Early detection efforts have been under way here for almost a decade, some involving students in intermediate and high schools. The Agriculture Department has implemented a largely effective interisland quarantine that at least has helped to delay the infestation for a decade. What's next?

Maui residents have shown impressive resolve in keeping the coqui frog confined to a relatively few areas, and coqui eradication still is considered a possibility. Most on Maui consider the little fire ant a much more serious threat than coqui. We have the advantage of being able to learn from Hawaii island's experience. Obviously, the community needs to play a major supporting role if there is to be hope of sustained eradication of the pest. One way to prevent the little fire ant from becoming established is to report unusual stinging ants. Call the state Department of Agriculture at 873-3962 or the Maui Invasive Species Committee at 573-6472 if you think you may have found little fire ants.

* Lloyd Loope is a research scientist with the U.S. Geological Survey stationed at the Haleakala Field Station. He holds a doctorate in botany from Duke University and is an active Maui Invasive Species Committee member. Na Moku Ola means "The Islands of Life," with special focus on Maui, Molokai, Lanai and Kahoolawe and the ideals of health and vigor we pursue.