Fire ants have been in the United States for over sixty years, and almost every American that lives in or frequently visits the quarantined states which they inhabit has had an unpleasant run in with these troublesome critters. Inhabitants of the Southeast who have ever stood unwittingly atop a fire ant mound know that the insects are aptly named. When the ants sting it creates a sensation similar to scorching caused by a hot needle touching the skin momentarily (1. Tschinkel 474). Fire ants are native to South America and were introduced to the United States in 1928 through a port in Mobile, Alabama. The ants were stowaways hidden in soil used for ballast and in dunnage dropped off the ships once they had sailed from South America to the ports of Alabama (2. Lockley 31). The two basic species of fire ants in the United States are the are black and red, they vary in length from one eighth to one quarter inch. Black fire ants arrived first followed shortly by the infamous imported red fire ants. Black ants (Solenopsis Richteri Forel) were the first to arrive and spread slowly but steadily despite government intervention to stop them from spreading(3. Lockley 33). These black ants would spread much further then the second wave of imported ants recognized as Solenopsis Invicta Buren or red fire ants(4. Lockley 33). This second wave of ants arrived in about 1945 and spread much more rapidly and dominated the previous more passive black ant(5. Lockley 34). Homer Collins, a fire ant expert, stated that "The new invader, known as the red imported fire ant, proved more adaptive and rapidly displaced the existing imported black ant. By 1949, Solenopsis Invicta Buren were the dominant species of imported fire ant. Ants could be found in commercial ornamental-plant nurseries in the heart of the Southeast." Red ants are a particularly aggressive ant species that, like the killer bees, are rapidly spreading northward from the Southeastern United States, and have traveled as far west as Texas and as far north as North Carolina. "Experts predict that the ants may eventually reach as far west as California and as far north as Chesapeake Bay."(7. Tschinkel 474). The spread of fire ants into new areas depends on many factors: the existing level of fire ant population, climate, competition, and natural predators . In areas where other ant populations are well established and an abundance of natural enemies exist, colony establishment is hindered because of the threat to the queen and the competition for resources. Man and his need for cleared land has created open sunny areas free of natural enemies and fewer competitors and inadvertently aided the spread of the fire ants(8. Lockley 35). Fire ant infestation is a very serious problem in the Southern United States ranging from Florida, West along the Gulf Coast region, to West Texas. Over 200,000,000 acres of land in the United States and Puerto Rico are infested with fire ants. They pose a major economic threat to the agricultural and ranching industries, lawns, gardens and recreational areas, as well as a threat to animal life and even human life. The total cost of controlling the ants, preventing the damage, and treating the medical problems in urban and rural areas is estimated to be $2.7 billion per year (9. Lockley 36).
When native species are defeated by aggressive invaders, the cost is measured in lost species and disrupted communities. The result, predicted ecologist Gordon Orians at the 1994 Ecological Society of America Conference, will be the "Homogocene," an era in which the world's biota is homogenized through biological invasions(10. Lockley 37). Fire ants use their stingers to immobilize or kill prey and to defend ant mounds from disturbance by larger animals such as humans. Any disturbance sends hundreds of workers out to attack the potential nourishment or predator. The ant grabs its victim with its mandibles (mouth parts)...
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