Abstract

Understanding how individuals interact with biotic and abiotic factors in their habitats, and how these interactions influence movement through landscapes is a key step in understanding dispersal events. The world is experiencing increased introduction of non-native species into new regions, however without an understanding of how species use the space they occupy, it is not possible to understand how dispersal events occur. We studied the short- and long-term movement patterns of a non-native butterfly species in Montreal, Canada: the European common blue butterfly, Polyommatus icarus, to determine whether the movement patterns of these butterflies over multiple days can be predicted by individual movement behaviours measured over short time periods. We asked what factors can predict short-term movements in females of this species, and whether these short-term movements can be used to predict long-term movements. We examined short-term movement by following individuals over short time periods and compared these movements to long-term movements observed via a mark-release-recapture study. In doing so, we found that flowering, host-plant species presence, increased vegetation height, and road edges can predict short-term movement, and that the short-term movement model produced can be used to accurately predict long-term movements when they are less than 100 m. These findings suggest that an understanding of ground cover characteristics is important in being able to predict the dispersal of most individuals, but that further work will be required to accurately predict long-distance dispersal events, which are what appear to be driving range expansion of P. icarus in North America.