It's been just over two years since Australia began its eradication campaign against the red imported fire ant (Solenopsis invicta). Recently, the prime method used against these biting insects, poison bait, is under investigation by the Queensland government, after several homeowners complained that their pets had died. As reported at news.com.au, the government is denying that the bait could be what caused the deaths of dogs, birds and fish in southeast Queensland. The bait used reportedly needs to be present at a low toxicity, since it works by interrupting the ant's growth cycle, and is meant to be eaten after it's been taken back to the nest. The poisons contained in the bait are S-methoprene and pyriproxyfen (.pdf link), chemicals also found in products such as flea-control collars.