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Maintaining pyric herbivory, the fire-grazer interaction, in grasslands requires a mechanistic understanding of the effects of landscape heterogeneity on grazer movements and habitat selection. Using an analytic framework for simultaneously quantifying the effects of habitat preference and intrinsic movement on space use, we examined how female bison assess the forage quantity-quality tradeoff at the landscape-scale. We evaluated the association of dynamic, biotic forage resources and static, abiotic landscape features with movement and habitat selection in an experimental mesic grassland, Konza Prairie Biological Station. At Konza Prairie, forage resources vary in response to prescribed burning, grazing by a native grazer, and variable weather. We integrated 6 years of growing season locations of GPS-collared plains bison with their forage landscape derived from vegetation surveys (biomass and foliar protein content) to understand what drives bison movement. Preference for high foliar crude protein content and low stature forage structure was consistent across years, although substantial variation in the magnitude of selection of these resources occurred among years. In years of below-average plant productivity, the strength of selection for high foliar crude protein content was greater than in years of normal to above average plant productivity. Avoidance of areas with high herbaceous biomass content was strongest during years of low plant production. Climatic interactions between plant quality and quantity seemingly shaped bison distribution as they sought to maximize nutrient gains by selecting areas containing short or immature plants of high nutrient (protein) value. Our results provide experimental evidence for documenting a key behavioral mechanism that drives fine-scale movement of a large grazer in response to fire- and local-climate-induced changes in forage attributes.