Brisbane is barely coming to terms with potentially the biggest ecological disaster ever faced. The Red Imported Fire ant (Solenopsis invicta) thought to have arrived from a port in Argentina through trade. The Fire ants have invaded most of the south western suburbs, spreading out from original infestations at Wacol, to Kenmore Hills, Karalee, Jindalee, west to Redbank, and east to Parkinson and Sunnybank Hills. Another infestation from North America covers the Port of Brisbane and ants have flown across the Brisbane river to Nudgee, Eagle Farm and Manly.

A massive baiting program commenced in September 2001 by the Department of Primary Industries (DPI), and will be initially run for 3 years. Funding from all states and the Commonwealth to a total of $123 million will employ over 400 staff who will be trained to spread the baits (both on the ground and aerially) and advise householders.

The baits, which include Amdro, or pyriproxyfen or hydramethylnon (which is used depends on the presence of water) in a soy base to attract the protein-loving ants, contain small doses of chemicals to arrest the development of the workers and the queen, and stop food being absorbed, starving the workers. Areas with major infestations and active nests in places like schools, parks and pavements, are being treated with faster working liquid insecticides. All the insecticides have been used before (methoprene is regularly sprayed along the coast for mosquito control), and the dosage is much less than those insecticides still used by so many householders to spray cockroaches, ants and spiders. The Qld Deparment of Primary Industries (DPI), advises that for Baits to affect mammals more than five times their body weight of the baits has to be ingested, and as most residential areas will only have half a teaspoon spread over their back yards, it is unlikely larger, fast moving animals like rats and antechinus will be affected.

Despite two rounds of the baiting program being completed since September, the imported fire ants continue to move. Queen ants flew out in January, and by now will have started news colonies somewhere downwind of their original nests. This stage of their life cycle is well suited to Brisbane's summer weather. New outbreaks have recently been recorded towards Ipswich and Sunnybank, and they have now also been recorded deep within the Redland Shire at Wellington Point. Despite the apparently continuing increases in Fire ants numbers and distribution, the DPI reports there is an 80% success rate in killing the nest colonies.

A benefit the research into ants as a part of monitoring this outbreak has been the research into all ant species within the area. As thorough a study of Brisbane's ants has never been conducted, particularly in such magnitude. Forty-five genera of ants have now been identified within Brisbane, with some of these also imported species but not currently recognized or seen as destructive as Fire Ants.

There is a lot still to be done. Research into alternative control methods - other than using insecticides - has only recently got underway. Different chemicals and bait attractants are being studied. Few natural predators appear to enjoy the imported fire ants. New methods for treating contaminated soil and bales of hay are being trialed. However, in such a massive undertaking, there are still communication and public relation issues for all involved.

Some 64 000 blocks have been treated, and 18000 samples of ants tested, with 15% of these proving to be fire ants. Only 170 households have refused entry to the DPI inspectors. Treatment can be made compulsory if DPI suspects there are active nests on a property, and all efforts are being made to get cooperation from residents and from absentee landlords and owners of undeveloped blocks.

There have been 741 fire ant infestations in these western suburbs and, if untreated, they can certainly affect the way people use their gardens and house pets and livestock. There is also an apparent loss of biodiversity in area affected by the ants. Invertebrates affected by the baits, small lizards particularly the Garden skinks (Lamproholis delicata) and possibly even many of the ground nesting birds such as plovers as victims of the ants predation.

Monitoring to assess the impact of both fire ants and the insecticides being used continues with WPSQ members and other volunteers are monitoring the presence and absence of skinks. Through our Echidna Watch, WPSQ is making an all out effort to locate and monitor echidnas within fire ant affected suburbs. Echidnas, due to their specialised ant and termite based diet, stand out as an obvious species which will be affected by the absence of ants and other invertebrates following baiting.

DPI has established a community environmental committee, with representatives from WPSQ, local governments, the Museum, several catchment groups, consultants and Aboriginal community leaders. This committee meets monthly, and reviews progress, monitoring, and has assisted in setting priorities for wildlife research programs. There is still concern that some plants with limited distribution in Brisbane may be affected by the absence of ants. Brisbane City Council is undertaking a major review of its threatened flora and fauna. A number of universities have funded major projects into fire ants and their effects, and this should increase the current knowledge of Brisbane's wildlife and ecology.

What is essential is that the public continue to cooperate with DPI, that local governments continue to monitor and assist, and that nurseries and businesses within the infested and buffer areas implement their control plans. New quarantine and trade movement restrictions will came into law on 1st March 2002, and these will prevent movement of potentially contaminated soil, machinery and plants in southeast Queensland. It is up to us all to play our part in containing and hopefully controlling this menace to our unique lifestyle and ecology.

Residents in fire ant areas who are interested participating in WPSQ's Echidna Watch should contact the Society. Materials and instructions are provided free.

More important information about Fire Ants can be found on the Queensland Government DPI Web Site.

For more information about the poultry shed grant scheme and other activities, contact Wildlife Queensland by email or call +61 7 3221 0194.