Behavioral changes of a juvenile gorilla after a transfer to a more naturalistic environment

Abstract

Play behavior and stress‐associated behavior of a captive juvenile gorilla were observed before and after his transfer to a larger and more natural environment. The gorilla was observed for 4 months after the transfer and at 1 and 4 years after the transfer. Throughout his first month in the new environment play decreased dramatically. Although play subsequently increased again 2 months and 1 year after the transfer, it never reached the levels of play in the old environment. Four years after the move his play had decreased again to the low level of his first month in the new environment. Two of his stress‐associated behaviors, coprophagy and regurgitation/reingestion, decreased after the transfer. Self‐clasping behavior increased initially in the new environment and remained at high levels 1 year after the move. Four years after the move his self‐clasping behavior was significantly less than at 1 year after the move; however, it continued to be significantly greater than in the old environment. These findings suggest that larger and more natural environments do not necessarily result in more play activity or a reduction in all stress‐associated behavior.