What ignites fire ant density and impacts in longleaf pine ecosystems?

Abstract

Invasive invertebrates are studied due to their impacts on human and ecosystem health, but impacts on native invertebrates are less known. The red imported fire ant (RIFA, Solenopsis invicta) is an ideal model species to quantify this relationship is they take advantage of disturbed landscapes, which is problematic for disturbance-mediated longleaf pine ecosystems (Pinus palustris) of the southeastern United States. I hypothesized that RIFA mound numbers are driven by environmental variables (e.g., prescribed fire, region, disturbance history) in longleaf pine ecosystems, and that higher RIFA presence would decrease native and increase non-native ant species richness. I tested these hypotheses on 11 properties in Florida and Georgia, and results indicated that RIFA mound numbers do relate to certain environmental variables and higher RIFA presence did decrease native and increase non-native ant species richness. My findings can help land managers in balancing costs of invasive species control and meeting conservation goals.