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Activity is a component that has been found to contribute 10% to the biological variation of residual feed intake (RFI) in cattle, even in feedlots. Greater cattle activity may be expected within cattle on pasture due to the ongoing search for high quality and quantity forage and water sources, and the need to regulate exposure to environmental variables (e.g., insects, wind, and temperature). These behaviours inevitably influence animal maintenance costs. The objective of this study was to test whether cattle with divergent RFI as determined by molecular breeding values (MBV) have different activity levels on pasture. 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) molecular breeding values for RFI were fitted with AfiAct II pedometers to track their activity (lying, standing and movement time, lying bout, movement rate) while rotationally grazing a series of large pastures over a period of five months. Data were separated into season (native grassland growing, cultivated, wetland, and native grassland dormant) for comparisons and analysis. Preliminary activity data show both high and low RFI animals spend up to 80% of their time standing or lying down. There appear to be trends of reduced movement within the dormant season compared to all other pasture seasons. Statistical analysis of activity for each RFI group and implications of the results for rangeland managers will be shared in this poster.