Abundance, diversity, and activity of ants (Hymenoptera : Formicidae) in oak-dominated mixed Appalachian forests treated with microbial pesticides

This study is part of a long-term analysis of nontarget effects of microbia l pesticide application in the George Washington (Augusta County, VA, USA) and Monongahela National Forests (Pocahontas County, WV, USA). Ants were co llected using pitfall traps to assess the effect of Bacillus thuringiensis Berliner variety kurstaki (Foray 48 F) and gypsy moth nuclear polyhedrosis virus (Gypchek) application on ant communities. Ant samples were also compa red by sampling years. Pitfall traps were operated for 45 wk during summers of 1995-1997. A total of 31,732 ants was collected from pitfall traps; the y belonged to four subfamilies, 17 genera, and 31 species. The ant species richness, diversity, abundance, and species composition did not change as a result of the treatments. Further tests of ant abundance were suggested be cause the test power was low. Comparisons between sampling years showed a v ery similar species composition and species evenness. There was a significa nt decrease in ant abundance in the third year of sampling, which might hav e been caused by over-trapping. Some rare species did not appear in the sec ond and third year of sampling.