A comparison of behavioral activity and spatial relationships in a captive populations of western lowland gorillas (Gorilla gorilla) and common chimpanzees (Pan Troglodytes)

Dana Science Building, 2nd floor

Under the direction of Dr. Renee Godard

The fundamental mission of most modern zoos is conservation, research, and education, with a strong focus on animal welfare that provides adequate space and enrichment for species to maintain natural behaviors. We compared the behavioral activity and spatial relationships of two ape species (lowland gorillas - Gorilla gorilla and common chimpanzees – Pan troglodytes) maintained in separate large natural enclosures at the North Carolina Zoo. In the wild, lowland gorillas (Gorilla gorilla) are typically found in small harems with a dominant silverback male, several females and juveniles, while chimpanzees are commonly found in fission-fusion societies comprised of many adult males and females. While the social dynamics in the chimpanzee troop at the zoo were more similar to the wild pattern, the gorilla group was comprised of only males. We recorded the behaviors of four of the eight chimpanzees in the outdoor chimp habitat and all five gorillas in the gorilla enclosure for 30 minutes. This was followed by a 30 minute focal sample that examined group cohesiveness by noting distance relationships between individuals in each enclosure. Gorillas did not exhibit any social behavior, were highly, sedentary and maintained interindividual distances > 5m for more than 50% of the time. On the other hand, chimpanzees showed significantly higher rates of locomotion and social interaction and most often found within 2 m of another individual (over 90% of the time.) We compared these patterns to other captive and wild populations of both species and reflect that captivity and the odd social dynamics generated by captivity likely play a role in the observed behaviors.