This thesis is an investigation of the behavioural response of elk (' Cervus elaphus') to the spatial distribution of resources with respect to diet choices and movement patterns. I first examined the effects of plant nutritional quality and abundance on the forage selectivity of elk. Elk made adjustments to their selectivity in accordance with predictions of optimal foraging theory. Selectivity varied according to habitat quality, such that elk broadened their diets in response to decreased availability of high quality plants, maintaining intake rates in low quality habitats. I then examined elk movement dynamics. Elk behaved as area restricted searchers, employing at least two very distinct movement states while engaged in daily activities. An intensive search mode was used while foraging, whereas an extensive search mode was used while looking for resource patches. Encounters with high quality forage patches triggered the switch from one mode to the next, creating bi-phasic spatial dynamics.