We are attempting to characterize effects of human landscape changes on spatial distributions, abundances, and patterns of dispersal for specialist insects and their plant hosts. Specialist insects are exemplars for understanding ecological responses to modified landscapes because plant hosts represent the only trophic level under direct human control, setting the stage for interactions at higher trophic levels. Further, specialists constitute the majority of described insects and are expected to be more sensitive to habitat modification than generalists. We are focusing on two systems in which native, edge-specialist tree species (Prunus serotina and Juglans nigra) are host to monophagous fruit flies (Rhagoletis cingulata and R. suavis), which are in turn host to specialized parasitoid wasp taxa. ‘Stacked’ specialization across the three trophic levels facilitates the formation of specific predictions regarding spatial distributions; host presence is a necessary prerequisite for insect presence. We are integrating ecological and population genetics methods with cutting-edge geographical tools to characterize spatially explicit intra- and inter-trophic species abundances and gene flow patterns in a 360 km2 urban/ agricultural landscape over multiple years.