Assessment of Potential Karner Blue Butterfly (Lycaeides melissa samuelis) (Family: Lycanidae) Reintroduction Sites in Ontario, Canada

Although species reintroduction is useful as both an integral part and a performance indicator of habitat restoration, it is not a risk‐free process. Evaluation of potential reintroduction sites is often crucially important in reducing chances of failure. Despite its importance, there is no standard way to do so. This study applied a systematic scheme to evaluate five potential reintroduction sites for the endangered Karner Blue butterfly (Lycaeides melissa samuelis Nabokov) in Ontario, Canada, by looking at both biotic and abiotic aspects. Field data were collected in 2003 from these sites, and three potential founder butterfly sites in the United States. We used data collected from the U.S. sites to determine the minimum standards for ecological requirements of the Karner Blue. Data from the Ontario sites were then compared against these standards. The results show that all five potential reintroduction sites are of lower quality, at least in certain aspects, compared with the three potential founder butterfly sites. This implies that success is not guaranteed if the Karner Blue is reintroduced into these sites under current habitat conditions. Further site restoration is required and should focus on the shortcomings identified for individual sites in this study. The lessons from this study are useful for potential reintroduction site assessment in other restoration projects because they reveal whether the sites are ready for species reintroduction and, if not, how they need to be improved.