Invasion of Polygyne Fire Ants Decimates Native Ants and Disrupts Arthropod Community

摘要: The fire ant Solenopsis invicta Buren invaded southeastern United States from South America >50 yr ago. Urban and agricultural consequences of this invasion are well documented; however, ecological effects still poorly understood. Increasing frequencies polygyne or multiple—queen ants in Texas other areas the Southeast disturbing because nest densities new form often ten times as great those more familiar monogyne form. We studied impacts a on surface—active arthropods at field station central Texas. Arthropod abundance species richness were assessed using combination baits, pitfall traps, litter samples. This decimated indigenous fauna. Competitive replacement appears to be primary mechanism behind effect. Species infested dropped by 70%, while total number native individuals 90%. Of 35 collected study, 23 either significantly less common absent sites; only S. was sites. most dramatic effect 10—30 fold increase sites–of which >99% imported invicta. impact severe, but substantial. isopods, erythraeid mites, tumblebug scarabs declined significantly, ground crickets, brachypterous roach, symbiotic scarab increased significantly. Overall, non—ant 30% lower sites, individual numbers 75% lower. Total arthropod (including ants) 40% These data indicate that pose substantial threat biodiversity communities.