Urban-adapter species facultatively exploit human-subsidized resources in the urban and suburban matrix. We used the woodchuck (Marmota monax) to study how aspects of autecology in an urban-adapter can vary across a gradient of urbanization. We captured and monitored woodchucks by radiotelemetry in southern Illinois from summer 2007 to spring 2009. We captured 47 woodchucks (19 adults, 19 yearlings, 8 young-of-the-year) during the active seasons, and implanted radiotransmitters in 17 adults and 3 yearlings (13 F, 7 M). Overall annual survival was estimated to be 0.76 ± 0.12, with three confirmed mortalities during the study period. Survival and home-range size did not vary by % urban landcover in a buffer surrounding an individual's home range. Habitat-selection analyses indicated that rural edge was the highest-ranked habitat at the home-range scale, whereas urban cover (specifically, developed areas with human structures) was most highly ranked at the within-home-range scale. Body condition was negatively related to % urban landcover. Overall, our findings indicated no clear relationship between woodchuck ecology and urbanization level within our study area. However, our data on body condition and adipose composition, although preliminary, suggested a possible mechanism for variation in overwinter survival across the urban-rural gradient.