Wildlife-habitat relationship studies are important for understanding the factors that determine where species occur in space and time. Habitat selection by generalist species should be studied on fine spatial and temporal scales to avoid masking important differences between seasons, localities, or orders of selection. I conducted the first study of habitat use and general ecology of North American porcupines (Erethizon dorsatum) in a coastal dune environment. Specifically, I assessed changes in body mass, home range size, and habitat selection in relation to the potential for seasonal nutritional and survival bottlenecks as reported elsewhere. Although they are considered generalists, porcupines have adapted specialized feeding strategies allowing them to survive periods of harsh weather and low food availability. In this study, porcupines were selective in their habitat use at the home-range and within-home-range scales during both summer and winter. In summer, porcupines selected willow-dominated swales, marshes, and fruit trees, and during the winter they selected coastal scrub, dunes, and conifer forests. These changes were most likely driven by forage availability, leading to dramatic body mass loss between summer and winter. On average, females lost 7.5% of their body mass and males lost 17.8%. Further, four out of five mortalities occurred during the winter, which is consistent with nutritional decline. Porcupines had larger home ranges during the summer than the winter by approximately 31%. These spatiotemporal changes are similar to those reported elsewhere, indicating that similar strategies are used by this habitat generalist across its range
