Impact of the Red Imported Fire Ant on Native Ant Species in Florida

Invasion by ants and their subsequent displacement of native fauna is a well known phenomenon. These invasions are most devastating on islands. The red imported fire ant, Solenopsis invicta Buren, is a pugnacious, immensely successful invader of disturbed habitats throughout the Southeastern United States. The successful movement of S. invicta into uninfested areas by taking advantage of man-made ecological disturbances, other than large-scale insecticidal treatments, has not been properly documented. Both S. geminata and P. dentata showed significant negative correlations when compared to S. invicta in percent occurrences, in specimens, and in number of sites occupied. Native species which occur in habitats and niches similar to S. invicta have generally been negatively affected by the habitat disturbances in Gainesville and the corresponding increases in S. invicta populations. Odontomachus brunneus occurrences showed an unexpected positive correlation with increasing S. invicta occurrences.