Imported fire ants, Solenopsis richteri and Solenopsis invicta, are menacing health hazards for the 20 to 30 million people who live in the fire ant-infested regions of the southeastern and south central United States. In the early 1900s, fire ants were brought into the port city of Mobile, Alabama, on vegetation and produce from South America. Their aggressive behavior compared to native ants and the favorable climate throughout the southeast allowed extensive spread. In 1985 it was estimated that fire ants infested approximately 250 million acres in eleven southern states and Puerto Rico.1 In infested areas fire ants account for 90% of all ant populations and stings from fire ants are more frequent than stings from other hymenoptera, becoming the most common cause of insect venom hypersensitivity.
A Comparative Study between Solenopsis invicta and Solenopsis richteri on Tolerance to Heat and Desiccation Stresses