GRASSLAND RESTORATION AND MANAGEMENT FOR THE REINTRODUCTION OF THE REGAL FRITILLARY, SPEYERIA IDALIA (DRURY) TO GETTYSBURG NATIONAL MILITARY PARK

Abstract

In an effort to increase threatened populations of a charismatic, grassland butterfly, Speyeria idalia,I have initiated a habitat restoration project at Gettysburg National Military Park, Pennsylvania, U.S.A. My manipulations at this site were designed for future reintroductions of this rare butterfly. The goal of this study was to examine experimental treatment effect (solarization vs. scarification vs. control) on densities of violets and nectar species and vegetation cover classes while restoring grasslands at the study site—all are essential habitat requirements for this rare butterfly. Lepidopteran and vegetation surveys were conducted from 2008-2010. By slightly changing the management regime, butterflies increased, and there was also a positive vegetation response (i.e., increased larval and adult host plants.) There were no significant differences in treatment effect on violet density or nectar transplant survivorship. Solarization was the most effective at increasing bareground and decreasing thatch, but conversely, it decreased cover of target warm-season grass species. Overall the site at Gettysburg is more suitable for a future reintroduction of S. idalia as a result of my field manipulations.