Patterns of abundance of fire ants and native ants in a native ecosystem

Abstract

. 1. This correlational study examines the relationship between the red imported fire ant ( Solenopsis invicta ) and native ants in a longleaf pine savanna. Fire ants are frequently associated with a decline in native ants throughout the invaded range, but fire ant invasion is often coupled with habitat disturbance. Invasion of fire ants into the longleaf pine savanna provides an opportunity to examine the structure of the ant community in the absence of habitat disturbance.2. Pitfall trapping was conducted within the longleaf pine savanna as well as across a naturally occurring soil moisture gradient, in plots that had been artificially watered.3. Species richness did not vary as a function of fire ant density. There was an inverse relationship between native ant density and fire ant density, but this abundance pattern does not necessarily imply a causal link between fire ant invasion and native ant decline. For individual species, fire ant densities were negatively correlated with the densities of only two native ant species, including Solenopsis carolinensis , a native species that potentially limits the invasion of fire ants. Additionally, fire ants and native ants respond differently to soil moisture, with native ants favouring drier conditions than fire ants.4. The possible exclusion of fire ants by some native ants, as well as differences in habitat preferences, provide alternative explanations for the frequently observed negative correlation between fire ants and native ants.

Extreme life history plasticity and the evolution of invasive characteristics in a native ant

“…Studies involving introduced, invasive ants show that both factors may play a role. Human activity played a major role in biological invasions involving red imported fire ants, Solenopsis invicta, and habitat disturbance (King and Tschinkel 2008) or habitat preferences (Stuble et al 2009) rather than interspecific competition had the greatest impact on ant communities. In contrast, Argentine ants, Linepithema humile, appear adept at invading undisturbed, native habitats and are a primary driver of ecological change (Holway and Suarez 2006).…”

Copperheads are Common when Kingsnakes are Not: Relationships Between the Abundances of a Predator and One of their Prey

“…We found no evidence that regional droughts (Fig. 7) or the Red Imported Fire Ant, the dominant ant species (Stuble et al 2009), had negative effects on Eastern Kingsnakes at Ichauway. Furthermore, Ichauway is located in a largely agricultural landscape and has potential for exposure to agrochemicals.…”

A checklist and assemblage comparison of ants (Hymenoptera: Formicidae) from the Wichita Mountains Wildlife Refuge in Oklahoma

“…This species made up 35% of all individuals in pitfall traps, but was disproportionally collected in grasslands (C. lineolata abundance: N Forest = 84; N Grassland = 1478). As invasive species management is a priority for wildlife refuges, C. lineolata is of particular interest as a previous study found its abundance was negatively correlated with the invasive S. invicta (Stuble et al 2009). …”