Abstract # 13109 Poster # 65:

Scheduled for Thursday, August 9, 2018 06:00 PM-08:00 PM: (Chula Vista ) Poster Presentation


S. J. Neal Webb1,2, J. Hau2 and S. J. Schapiro1,2
1Michale E. Keeling Center for Comparative Medicine and Research, 650 Cool Water Drive, Bastrop, TX 78602, USA, 2Department of Experimental Medicine, University of Copenhagen
     The NIH recommends that chimpanzees be maintained in complex, multi-male, multi-female groups of seven or more individuals as part of an ethologically appropriate environment. Reamer et al. (2016) showed that chimpanzees in groups of 7 or more animals exhibited more affiliative behavior than chimpanzees housed in groups of 6 or fewer. We explored how chimpanzee behavior differed as a function of 1) group size, 2) number of males per group, and 3) average age of the group, while controlling for housing type (dome vs. corral). We used 15-minute focal animal observations to collect 460 hours of data (N=121) at the National Center for Chimpanzee Care. Categories of behavior included locomotive, aggressive, submissive, sexual, abnormal, self-directed, and social proximity. Group size ranged from 4–10 animals (M=7.4). An ANCOVA showed that chimpanzees housed in groups of 7 or more spent more time affiliating (M=22%, SE=1.55%) compared to animals in groups of 6 or fewer (M=12.40%, SE=2.79%), p=0.005. Additionally, time spent resting was lowest (p=0.002) and locomotion was highest (p=0.008) in groups with 4-5 males. Lastly, chimpanzee behavior did not differ as a function of average age of the group (p>0.05). These results show that captive chimpanzee behavior depends on both group size and composition factors, and can be used to inform decisions concerning ways to achieve functionally appropriate captive environments through various size and composition combinations.