Michael Warriner
Friday, October 17, 2008 - 2:30-3:00
Since their initial introduction into the U.S., red-imported fire ants (Solenopsis invicta) have greatly expanded their range across several southern states. These non-native ants are now recognized as significant threats to public health and native species. One little examined impact of red-imported fire ants is their role as agents of soil change. The large mounds constructed by this species result in material from lower soil horizons being mixed with upper level material. The impact of red-imported fire ant mound-building on natural ecosystems, particularly ones characterized by unique soil compositions, has been little studied. Saline barrens are a rare natural community in southwestern Arkansas typified by soils high in magnesium and sodium salts. The barrens support a number of rare plant species including the federally threatened plant, Geocarpon minimum. Over the past two years, we have been investigating the soil properties of red-imported fire ant mounds in these sites. Abandoned mounds were found to differ significantly in terms of certain soil nutrients when compared to undisturbed barren soils. Results from these analyses will be discussed along with population aspects of red-imported fire ants in this natural community type.
Keywords: RED-IMPORTED FIRE ANTS, INVASIVE SPECIES, PEDOTURBATION, SALINE BARRENS