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Residual feed intake (RFI) is a heritable trait that can be used to measure feed efficiency in cattle and serve as a tool for managing beef operation costs. However, measures of RFI have mainly been evaluated under drylot conditions where animals are on a standardized diet with variation in foraging behaviour minimized. Evidence suggests that cattle in rangelands are highly selective while foraging, a phenomenon that applies across multiple spatial scales ranging from individual feeding stations to landscape locations. This is further affected by temporal variation in forage quality and quantity across the grazing season. Our study explored the relationships between cattle habitat selection and activity budgets with associated molecular breeding values (MBV�s) for RFI. Research was conducted at the University of Alberta Mattheis Research Ranch, 35 km north of Brooks, Alberta in the Mixedgrass Prairie. An identified subset of commercial cows with distinctly divergent (high and low) MBV�s for RFI were fitted with Lotek 3300LR GPS collars and AfiAct II pedometers to track their movements while rotationally grazing a series of large pastures for five months. We hypothesized that animals with low MBV�s for RFI (efficient) would utilize areas associated with higher quality forage for greater periods and spend less time moving, excluding travel to food or water sources, than animals with high MBV�s for RFI (inefficient). Behavioural data for each animal and treatment group was used to develop resource selection functions (RSFs) for identified cattle. Environmental factors contributing to seasonal selection of areas in pastures will be compared between low and high RFI group animals. We will discuss differences in habitat use between RFI groups and the potential implications for the use of breeding values for RFI in extensively managed cow/calf operations