"Species traits as predictors of the frequency of recolonization in prairie Lepidoptera"

Renae M. Steichen and Christopher Conoan are students at Drake University. Keith S. Summerville is Assistant Professor of Environmental Science and Policy in the College of Arts and Sciences at Drake.Restoration ecologists are increasingly turning to the development of models to predict how species move from a regional species pool into a restored community. Two untested assumptions of these models, however, are that ecologists have an understanding for which traits are predictors of species distribution and that such traits predictably interact to determine the community membership. The goals of this study were to sample the regional species pool of Lepidoptera and to determine whether combinations of species traits predispose species toward becoming members of the actual species pool within restored prairies. In 2004, we sampled 259 moth species from 13 Tallgrass prairie remnants and restorations in central Iowa. We used principle components analysis (PCA) to identify significant combinations of ecological traits that were shard by large groups of moth species and found that the model explained 81.6% of the variance. Species most frequently filtered from the regional species pool into prairies were those that: (1) had long flight periods and were multivoltine (2) displayed a feeding preference for legumes but not the Asteraceae or other forb families, and (3) were regionally abundant but relatively small in body size. Analysis showed significant differences in moth community composition among prairie sites, suggesting trait differences among species partly drive patterns of turnover among prairie sites. Finally, our results suggest that a combination of random and deterministic mechanisms interact to determine how moths attain community membership within restored habitats, and that these processes may operate relatively slowly for univoltine forb specialists with restricted distributions.Drake University, College of Arts and Sciences, Department of Environmental Science and Policy