Lepidopteran Community Response to Gypsy Moth Outbreaks is Robust to Guild Reclassification: A Reply to Summerville and Crist: Table 1.

Abstract

The breadth of individual feeding guilds in ecological studies ultimately depends on the specific objectives of an experiment (Simberloff and Dayan 1991). In this sense, ecological guilds themselves can be thought of as hypotheses of community classification not unlike the way in which phylogenies are hypothesized classifications of evolutionary relationships. The strength of a given hypothesis lies in its ability to withstand reevaluation in light of alternative hypotheses. Summerville and Crist (2002) have proposed an alternative to the classification of Lepidopteran feeding guilds published by Work and McCullough (2000). Here, we reevaluate our original conclusions in light of the proposed changes of Summerville and Crist and provide evidence that these changes do not affect our overall conclusions. In addition, we address several misinterpretations made by Summerville and Crist, and comment more generally on feeding guilds and indicator value analysis. Work and McCullough (2000) compared the abundance, diversity, and species composition of adult Lepidopteran communities in replicated stands of two deciduous forest ecosystem-types that occur in northern lower Michigan. Characteristics of these ecosystems, termed ecological landtype phases (ELTP), including overstory and understory vegetation, were published as part of an ecological classification system developed for the Huron-Manistee National Forests (Cleland et al. 1993). An objective of the study involved assessing the response of the Lepidopteran community to the first gypsy moth outbreaks that occurred in this region of Michigan. One finding from this study, that a subset of oak-feeding species was negatively affected by gypsy moth defoliation, was derived from a guild classification based primarily on host plant preference. One aspect of the original analysis of Work and McCullough (2000) involved classification of 98 species, collected as adults in July or August in oak-dominated stands (defined as ELTP 20 by Cleland et al.1993), into guilds according to host-plant preference reported by …