Abstract: | The purpose of this research was to explore the impact of the provision of manipulable and edible materials on the activity level of captive orangutans. The effects of three environmental conditions—bare exhibit, manipulables present, and manipulables plus edibles present—on the gross motor activity of four captive orangutans were compared using a multielement design. Results indicated that activity increased under the enriched conditions with increases in activity type specific to the environmental change. In addition, zoo visitors rated the exhibit more favorably on days the enriched conditions were in effect than on bare exhibit days. |