Relative Effects of Disturbance on Red Imported Fire Ants and Native Ant Species in a Longleaf Pine Ecosystem

• Published in: Conservation biology 2011-06, Vol.25 (3), p.618-622
• Main Authors: STUBLE, KATHARINE L., KIRKMAN, L. KATHERINE, CARROLL, C. RONALD, SANDERS, NATHAN J.
• Format: Article
• Language: English
• Subjects: Animals; Ants; Ants - physiology; Behavior, Animal; Conservation biology; Conservation of Natural Resources; diversidad; diversity; Ecological invasion; Ecosystem; Ecosystems; fire ant; Fire ants; Formicidae; hormiga de fuego; Insect colonies; Insect ecology; Introduced Species; invasion; Invasive species; invasión; Pinus; Population Density; Population Dynamics; Research Note; Solenopsis invicta; Species; Worker insects
• ISSN: 0888-8892; 1523-1739
• DOI: 10.1111/j.1523-1739.2010.01634.x

The degree to which changes in community composition mediate the probability of colonization and spread of non-native species is not well understood, especially in animal communities. High species richness may hinder the establishment of non-native species. Distinguishing between this scenario and cases in which non-native species become established in intact (lacking extensive anthropogenic soil disturbance) communities and subsequently diminish the abundance and richness of native species is challenging on the basis of observation alone. The red imported fire ant (Solenopsis invicta), an invasive species that occurs throughout much of the southeastern United States, is such an example. Rather than competitively displacing native species, fire ants may become established only in disturbed areas in which native species richness and abundance are already reduced. We used insecticide to reduce the abundance of native ants and fire ants in four experimental plots. We then observed the reassembly and reestablishment of the ants in these plots for 1 year after treatment. The abundance of fire ants in treated plots did not differ from abundance in control plots 1 year after treatment. Likewise, the abundance of native ants increased to levels comparable to those in control plots after 1 year. Our findings suggest that factors other than large reductions in ant abundance and species density (number of species per unit area) may affect the establishment of fire ants and that the response of native ants and fire ants to disturbance can be comparable. El grado en que los cambios en una comunidad median la probabilidad de colonización y dispersión de especies no nativas no está bien comprendido, especialmente en comunidades animales. Alta riqueza de especies puede impedir el establecimiento de especies no nativas. La distinción entre este escenario y casos en los que especies no nativas se establecen en comunidades intactas (carentes de perturbación antropogénica de suelo) y subsecuentemente disminuye la abundancia y riqueza de especies nativas es un reto basándose solo en observaciones. La hormiga de fuego importada (Solenopsis invicta), una especie invasora que ocurre extensivamente en el sureste de Estados Unidos, es un ejemplo de lo anterior. En lugar de desplazar competitivamente a especies nativas, las hormigas de fuego pueden establecerse solo en áreas perturbadas donde la riqueza y abundancia de especies nativas ya están reducidas. Utilizamos insecticida para