Long-distance animal movements have long fascinated humans. However, such movements necessarily translate to a requirement for extensive habitat, rendering the animals susceptible to natural and anthropogenic environmental changes, especially landscape fragmentation induced by linear infrastructure. In particular, fencing might be the most pervasive yet the least understood linear infrastructure that can extensively alter animal movement behavior, space use, and population dynamics. Importantly, fencing is often situated in social-ecological systems where humans and wide-ranging animals co- exist, hence altered wildlife spatial ecology subsequently affects human communities at the same time. In this dissertation, I examined wildlife responses to environmental changes, in particular fencing-induced fragmentation, and the complex social-ecological contexts of fenced landscapes. Working with collaborators, I first developed a guiding framework that synthesizes the pathways through which migratory ungulates respond to natural and anthropogenic environmental changes on a global scale. We then zoomed into two wide ranging sympatric ungulates, pronghorn (Antilocapra americana) and mule deer (Odocoileus hemionus) in southeast Wyoming, and examined their behavioral and spatial responses to fences. Specifically, we developed a spatial- and temporal-explicit approach, Barrier Behavior Analysis (BaBA), with which we quantified the within- and among-individual variations in barrier behaviors along a fence density gradient. Finally, we situated fences in social-ecological systems to understand why and how fences became wide-spread around the world, as well as their coupled social and ecological impacts. Combing theories and methods in movement ecology, behavior ecology, rangeland ecology, and landscape ecology, this work provides new insights into ungulate movement in a changing world. By elucidating the impacts of fences across social and ecological boundaries, this research also marks a step in developing effective strategies to make the landscape connected for both humans and wildlife.