Fire Ants

About Fire Ants
There are several different species of fire ants, most of them native to South America. They are called fire ants because their venom, injected by a stinger like a wasps or bees, creates a burning sensation. They are active and aggressive, preferring to fight rather than flee when disturbed. They are invasive species in many regions around the world because they spread easily, are highly adaptable, breed quickly and are aggressive with negative outcomes for biodiversity, agriculture and people.

The Little Fire Ant, Wasmannia auropunctata, was first found in the Pacific more than 35 years ago. Since then it has been reported from the Galapagos, New Caledonia, Wallis and Futuna, Solomon Islands, Hawaii, Tuvalu, Fiji and Vanuatu. Wasmannia is omnivorous and exclusionary. It has been blamed for reducing species diversity, reducing abundance of flying and tree-dwelling insects and eliminating spider populations. In disturbed areas such as agricultural and forestry land and in exotic habitats Wasmannia commonly shows population explosions. In many areas it is a serious agricultural pest including stinging workers, enhancing populations of honeydew secreting insects and interfering with parasitisation of pest insects. Documented benefits of Wasmannia to agriculture in pest control are few and outweighed by the negative impacts. Wasmannia also attacks vertebrates. On the Galapagos, it eats the hatchlings of tortoises and attacks the adult tortoises. In the Solomon Islands and New Caledonia it has been reported to attack the eyes of dogs, causing blindness. Recent reports indicate that Wasmannia is one of the greatest threats to Pacific conservation.

Fire Ants in Vanuatu
W. auropunctata workers are surprisingly small, about 2mm in length and light brown to golden brown in colour. Where present in villages and towns of Vanuatu, nests can be found around the base of posts. Worker ants commonly crawl up posts in search of food, including bed posts. It's quite annoying to wake up in the night from bighting fire ants.

It is said fire ants were introduced to Vanuatu from the Solomon Islands in the 1990s by an Anglican Church Mission boat, the Southern Cross, which imported timber to Sola, Vanua Lava for a Diocese building. Fire ant infestations in the Banks Islands of Vanuatu in May 2004 are tabulated below. The only places where tourists are likely to visit and therefore encounter fire ants are Sola and West Mota Lava.

Compared to other references on distribution and from local sources it appears fire ants have spread in Vanuatu. Local communities do not have the money or know-how to control or eradicate fire ants. Also, public awareness of fire ants is poor and almost zero outside of infested areas (eg Port Vila).

Advice for Travellers
If visiting a fire ant infected area you might want to take some household knock-down insecticide spray and try applying it to your bed posts before going to bed night. Don't spray extensively all about or spray the nests as this may actually result in the spreading of fire ants through workers moving queens to new locations to escape the disturbance. Efforts to reduce or eradicate fire ant infestations may do more harm than good and are best left to experts. Personal insect repellents (mosquito repellents) are not effective in repelling fire ants. When leaving a fire ant infested area don't carry any high risk materials (soil, plants, baskets of alean kaekae that have been in contact with fire ant infested ground) and make sure you're luggage is clean.

Fire Ant Links
If searching for fire ants on the web keep in mind that there are several different species with different biology and management strategies. There's a lot of information about the Red Imported Fire Ant, Solenopsis invicta but less about the Little Fire Ant, Wasmannia auropunctata.

Global Invasive Species Database
This online database is comes under the IUCN Invasive Species Specialist Group. You can search the database for W. auropunctata.

South Pacific Regional Environment Programme
In this site you can find the SPREP report on invasive species: Invasive Species in the Pacific: A technical review and draft regional strategy, SPREP, 2000. The chapter on Arthropod pests includes W. auropunctata.

Queensland DPI Fire Ant Home Page
The Queensland Government, Department of Primary Industries and Fisheries is spending millions of dollars on efforts to contain and eradicate S. invicta from southeast Queensland, Australia. There is a lot of information about managing fire ants in this site.

Last updated: June 2004 by Stephen.