The effects of disturbance on the red imported fire ant (Solenopsis invicta) and the native ant community

Abstract

Fire ant presence and dominance, coupled with immediate or sometimes even past disturbance, may have some effect on the native ant community. We used four timber harvest treatments (control, group selection, group selection with retention, and single tree selection) to measure the effect of disturbance on the fire ant population and native ant community. We collected ants using pitfall traps located in 18 treatment plots, with 20 collections per plot. We examined seed removal rates to determine if behavior toward elaiosome-bearing seed also was affected. Seed removal trials took place in four of the treatment plots with 19 observations before and 19 one year after the timber harvest treatments. Finally, we compared the ant community between areas of historically plowed (more than 70years ago) and unplowed soils using the current dominant ground cover as an indication of past disturbance.Fire ants were by far the most abundant ant species and the most frequent seed remover in the longleaf pine stands, regardless of silvicultural treatment. The disturbances due to timber harvest did not result in an initial change in abundance of fire ants or native ants, total species richness, or rate of seed removal. Habitat changes such as reduced canopy cover and increased woody debris associated with timber removal may influence changes in the ant community over time. Pre-treatment differences in ant community assemblage between blocks suggest that past disturbance may have more of an effect on the distribution of ant species, but this observation is not associated with historical soil disturbance.