Abstract # 119:

Scheduled for Friday, June 22, 2007 02:30 PM-02:45 PM: Session 13 (North Main Hall F/G) Oral Presentation

Wounding Data on Newly Formed Adult Chimpanzee (Pan troglodytes) Groups

A. Fultz, E. A. Orchard and L. Brent
Chimp Haven, Inc., 13600 Chimpanzee Place, Keithville, LA 71047, USA
     Aggression is a natural part of chimpanzee behavior. Most aggressive acts are performed by males but its causes are not well understood. This study investigated whether or not group formation, larger group sizes, or multi-male groups involved increased risks for wounding in captive chimpanzee groups. At Chimp Haven, 89 chimpanzees (M=42, F=47) live in 13 social groups. Chimpanzee groups ranged from 2-19 individuals and were 6-54 years old (mean = 30.68 years). Group formation involved 43 individual introductions of mostly unfamiliar chimpanzees. Wounds were categorized as: minor (no treatment required), moderate (required medical care, antibiotics) and serious (required sedation/suturing). A total of 145 wounds were reported (minor: 99; moderate: 41; serious: 5). During introductions, 0.6 wounds per group were noted, and over the first year wounding rates were low (month 1: 1.3; months 2-6: 0.86; months 7-12: 1.5 wounds/group/month). Sex and group size influenced wounding rates. Males received 64% of all wounds and 73% of serious wounds. Groups with seven or more males received significantly more minor wounds [F(2,10)=15.16, p<0.0009]. More wounds were reported during the process of group formation for the large group introduced more slowly (n=20) compared to the group introduced quickly (n=8). Larger groups had significantly more serious wounds [F(2,10)=4.2, p<0.046] and minor wounds [F(2,10)=19.1, p<0.0004]. Adult chimpanzees can be introduced safely and housed in various types of groups, with minimal incidences of wounding.