Abstracts of presentations: Abstracts 14-34

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 80 KB
• Volume: 45
• Category: Article
• ISSN: 0275-2565
• DOI: 10.1002/(sici)1098-2345(1998)45:2<166::aid-ajp3>3.0.co;2-u

✦ Synopsis

Access to outdoor environments has been promoted on several fronts as an important element of the long-term care of captive chimpanzees (Pan troglodytes). In order to document the potential benefits of outdoor access, this study compared the behavior of chimpanzees housed in outdoor/indoor runs (n=12) with those housed indoors only (n=13) at the Yerkes Regional Primate Center. These groups were matched for age, rearing history, and enrichment protocol; all subjects were housed in pairs or trios. Analysis of variance of 135 h of data found that chimpanzees with outdoor access showed significantly less abnormal behavior (e.g. coprophagy, regurgitation/reingestion), less yawning, and more selfgrooming (p<0.05). Rates of activity showed a significant interaction effect between housing and group size (p<0.01); outdoor/indoor-housed trios showed the highest level of activity. The temporal distribution of abnormal behaviors was markedly different between the two housing conditions. While indoor-housed chimpanzees showed a rise in rates with elapsed time since feeding, outdoor/indoor individuals did not, suggesting that increased environmental complexity may buffer captive chimpanzees from the effects of unnatural feeding regimens. These results suggest that outdoor access has a major impact on chimpanzee behavior. When compared to the results of ameliorative enrichment techniques furnished to the indoor-housed subjects, the small outdoor groups of chimpanzees showed broader and more dramatic improvements in well-being.