Tool use task as environmental enrichment for captive chimpanzees (2003)

Celli, M. L., Tomonagaa, M., Udonob, T. et al.

Abstract

Wild chimpanzees spend 50-80% of their time foraging, using tools and other forms of manipulation, while captive chimpanzees cannot. In this study, a device that elicits tool use was presented to six captive chimpanzees housed in pairs. The task successfully reduced inactivity by about 52%, increased foraging opportunity from 0 to around 31% and elicited tool use and manipulation. ... There was no statistical evidence of habituation to the device, though there was evidence of habituation to the materials.