The red-imported fire ant (RIFA) is the deadliest ant species in the United States, and while 280 fire ant species have been documented around the world, the RIFA is considered the most aggressive species of all. RIFAs often attack and kill rodents and even small pets, like kittens, and according to entomologist Mike Raupp, five percent of all RIFA sting incidents induce a deadly reaction, most often anaphylactic shock.
The RIFA is native to South America, but they were accidentally transported into the port of Mobile, Alabama from Brazillian cargo back in the 1930s. After arriving in the southeast US, RIFAs began to expand their invasive habitat in the region by 120 square miles per year. Today, these invasive ants can be found in 15 states in the southern half of the country, and as much or possibly more than 1 billion dollars per year is spent on RIFA eradication programs in the US.
RIFA arrived in Louisiana during the 1950s, and today, they have established colonies throughout the entire state. While RIFA colonies cannot be eradicated once they establish an invasive habitat, officials with the LSU Ag Center have been successfully controlling fire ant infestations with baits that contain insect growth regulators. According to a recent nationwide survey of pest control professionals, fire ants were the sixth most commonly managed ant pests during 2016.
Bait is the only RIFA control measure that can be placed throughout a residential yard. All other control measures, such as wettable powders, emulsifiers, and liquid insecticides must be applied directly to existing nesting mounds. Eliminating RIFA colonies is easier in wide open landscapes than in individual residential yards, and once one neighborhood yard becomes infested, neighboring yards rapidly follow. This is why pest control professionals treat entire subdivisions as opposed to single yards. Today, US federal and state agencies are working together to develop a biological RIFA control program involving predatory and parasitic phorid flies.
Have you ever sustained stings from fire ants?