There are several species of fire ants in the United States. Four species are native ants. Two species were accidentally imported from South America. One species of fire ant is called “black fire ant”. All of the other species are reddish in color. The red imported fire ant, Solenopsis invicta (Buren), is probably the best known (and most notorious) of them all.
Fire ants got their name from the nasty bite and painful sting that they can deliver. The red imported fire ant came to the United States during the 1930's or 1940's. Since the ants live in the ground, scientists think they came in a ship that was loaded with soil as ballast.
The ants arrived near Mobile, Alabama. Since their arrival, they have spread across the southern states. Now these ants are found from the Carolinas to California. They have been reported as far north as Kansas and Maryland.
Fire ants are very aggressive. The workers climb onto a person's foot and then they all seem to bite at the same time. The workers clamp their jaws into the victim's skin, then they swivel their abdomen around so they can sting.
The sting of the fire ant worker delivers very potent venom. Some people experience allergic reactions to the sting. Each year a few people die as a result of these stings. Children and pets should be supervised closely. If a person is stung, he or she should be watched carefully. If the victim shows signs of allergic reaction, a doctor should be consulted.
In areas where fire ants are common, there can be hundreds of colonies per acre. The workers gather insects, seeds, nectar, and honeydew to feed the colony. By their food gathering and their aggressiveness, fire ants can wipe out or displace most other types of ants in their territory.
Beside the medical impact, since its arrival, the red imported fire ant has had a serious economic impact. Fire ants have dramatically affected cattle and livestock production. Farmers and ranchers must provide for newborn animals to avoid injury from fire ant bites and stings. Because of the nesting, fire ants damage transformers and other electrical equipment. They cause equipment failures, short circuits, and even blackouts.