The exotic Nylanderia flavipes (Hymenoptera: Formicidae) in Cleveland, Ohio, and its impact on local ant diversity

In 2005, the non-native Nylanderia flavipes was first discovered in the state of Ohio. Here we report the results of a study designed to evaluate the impacts of that species on local ant diversity and community composition. The most drastic change we found was a 6-fold increase in total ant abundance, with over 87% of all ants collected belonging to that species. The high numerical dominance of N. flavipes however did not lead to detectable changes in the species richness and abundance of the native ant community, but was responsible for decreased community evenness at the sites where this ant occurred. Nylanderia flavipes did not exhibit aggression towards native ants and did not engage in interspecific combat at baits. The differences in ant community composition between the sites with and without N. flavipes are likely a result of factors other than the presence of Nylanderia itself, such as disturbance history. The lack of response from the local ant community to the presence of N. flavipes may also be indicative of a recent introduction, but data on the date and means of introduction of N. flavipes in the area are lacking. Although we found no detectable impacts on native ant communities, the high local abundance of N. flavipes may be advantageous in discovering and utilizing available resources and thus impact native ants via exploitative competition.