We studied the home range and habitat use of northern map turtles (Graptemys geographica) in Québec, Canada, in a river comprised of multiple channels and islands. To better represent the home range of turtles in such complex river landscapes, we developed the complex linear home range (CLHR), a generalized estimator designed to more accurately represent turtle home ranges based on their movements in multiple channels, unlike the simple well-known linear home range and the minimum convex polygon estimators. The CLHR appears to be an estimator that can permit the interstudy comparison of turtle home ranges in other rivers characterized by multiple channels and can be calculated easily using GIS software.