Understanding the spatial ecology of species at risk is essential for conservation because this information forms the base from which management and recovery plans are delineated. We studied microhabitat selection and evaluated the effect of reproductive class on daily movement patterns, home ranges, and seasonal activity of Blanding's Turtles in the St. Lawrence Islands National Park, Ontario, Canada. We also consider the potential conservation/management ramifications of differences in habitat use between the reproductive classes. We monitored 38 Blanding's Turtles (20 males, 13 gravid females, and 5 nongravid females) from April 2008 to August 2009 via radiotelemetry. Reproductive class did not have a significant effect on the mean daily movement of turtles in May, July, and August. In June, however, gravid females moved significantly more (mean  =  400 ± 49 m per day) than males (mean  =  194 ± 22 m per day). Reproductive class also had a significant effect on turtle home-range size, although high individual variation was observed (range  =  1.6–40.6 ha). Gravid females had significantly larger home ranges (mean  =  20.3 ± 3.5 ha) did than both males (mean  =  8.2 ± 1.8 ha) and nongravid females (mean  =  7.3 ± 3.2 ha). At the microhabitat scale, Blanding's Turtles selected colder water with more submerged and floating vegetation and avoided open water. Our results highlight the importance of stratifying field observations and spatial data by reproductive class and time and including terrestrial habitat in home-range analyses of Blanding's Turtles.