Electronic Thesis and Dissertation Repository


Master of Science




Dr. Nusha Keyghobadi


Landscape changes such as habitat fragmentation and habitat loss are contributing to a global decline in biodiversity. While habitat fragmentation research has mainly focused on species that avoid edges, or the boundaries between different landcover types (negative edge response), a hypothesized resource distribution model predicts that species that require complementary resources in different landcovers will be most abundant at edges (positive edge response). Adults of Eastern Tiger (Papilio glaucus) and Spicebush (P. troilus) swallowtail butterflies require forests for oviposition sites and meadows for nectar resources. I examined the relative abundance and flight orientation of both species in relation to the forest/meadow edge to evaluate their edge response. Overall, I found that their distribution and flight behaviour was consistent with the positive edge response model, however there were differences between species and sexes. My results suggest that some degree of forest fragmentation in southernwestern Ontario can actually benefit some native species.