Ecological Effects of Solenopsis papuana on Invertebrate Communities in O'ahu Forests.

Abstract

The thief ant, Solenopsis papuana, is the most common invasive ant found in upper elevations of mesic forests of Oʻahu, raising concerns about its ecological impacts in these areas. I developed monitoring and control methods to measure and reduce S. papuana densities in experimental field plots, and subsequently assessed invertebrate community responses to this ant suppression six months and one year later, using leaf litter and pitfall sampling methods. Responses in overall community composition, species richness, and abundances of taxa were mixed, but altogether, suggest that S. papuana has broad but relatively weak effects on current ground-dwelling invertebrate communities, which are dominated by nonnative species. Specific taxa, however, may be more vulnerable. Eradication of this ant from the Waiʻanae Mountains is not feasible, but information from this study may help land managers decide whether controlling this ant in small areas to conserve rare and sensitive invertebrate species might be useful.