Gorilla behavior in response to systematic alternation between zoo enclosures

Abstract To determine the effects of relative novelty on captive gorilla behavior, the regular alternation of two groups between complex naturalistic enclosures was studied at Zoo Atlanta. A continuous behavioral change sampling method was used to obtain information on behavior, and instantaneous scans at 10-min intervals provided information on the location of all gorillas in the focal group. An analysis of 226 h of behavioral data and 1386 map location scans showed enclosure rotation was associated with increased enclosure use and feeding and a decrease in self-directed behavior. Gorillas were more likely to increase exhibit use and visibility to zoo visitors during a 4-day novel phase compared to subsequent days in the exhibit. Because of constraints in exhibit design, however, increased use of exhibit did not always result in greater visibility of gorillas to zoo visitors. Gorillas increased locomotion, social distance, use of grass areas, and visibility to the public in their “Away” exhibit compared to their “Home” exhibit. Regularly alternating gorillas between zoo exhibits is a form of environmental enrichment that can increase gorillas’ use of exhibit space and increase activity level.