Impact of ecological and social factors on ranging in western gorillas

We examined the influence of ecological (diet, swamp use, and rainfall) and social (intergroup interaction rate) factors on ranging behavior in one group of western gorillas (Gorilla gorilla gorilla) during a 16-month study. Relative to mountain gorillas, western gorillas live in habitats with reduced herb densities, more readily available fruit (from seasonal and rare fruit […]

Effects of hand-rearing on the reproductive success of western lowland gorillas in North America

This study sought to assess the potential effects of hand-rearing by evaluating the relationships among rearing type and reproductive success in the American Zoo and Aquarium Association’s Species Survival Plan® for western lowland gorillas. Our study included data on 697 gorillas: 257 wild-born (WB) and 440 born at zoos or related facilities in North America. […]

Gorilla Adaptations to Naturalistic Environments

In the past few decades there have been increased investigations into the effects of captive environments on behavior. Simultaneously, zoological gardens have undergone a revolution in philosophy and design, resulting in a proliferation of “naturalistic” habitats. Complex environments such as these have been found to affect the behavior of captive animals favorably, including increasing reproductive […]

Mother-infant interactions in western lowland gorillas ( Gorilla gorilla gorilla): Spatial relationships, communication and opportunities for social learning

This study investigated mother infant interactions in lowland gorillas (Gorilla gorilla gorilla) with particular focus on the relative role of mothers and infants in creating situations that are potentially conducive to infant social learning. Eleven gorilla mother infant dyads were focally observed in weekly 1-hr sessions for 12 months. Spatial relationships were affected by age […]

Western lowland gorillas (Gorilla gorilla gorilla) change their activity patterns in response to frugivory

The most important environmental factor explaining interspecies variation in ecology and sociality of the great apes is likely to be variation in resource availability. Relatively little is known about the activity patterns of western lowland gorillas (Gorilla gorilla gorilla), which inhabit a dramatically different environment from the well-studied mountain gorillas (G. beringei beringei). This study […]

The birth of an infant decreases group spacing in a zoo-housed lowland gorilla group (Gorilla gorilla gorilla)

Changes in group composition can alter the behavior of social animals such as gorillas. Although gorilla births are presumed to affect group spacing patterns, there is relatively little data about how these events affect gorilla group cohesion. We investigated how members of a western lowland gorilla group (n = 6) at Lincoln Park Zoo (Chicago, IL, USA) […]

Western lowland gorilla (Gorilla gorilla gorilla) birth patterns and human presence in zoological settings

There is some evidence to suggest that zoo visitors may have a disruptive impact on zoo-housed animals, especially primates. While some consider western lowland gorillas (Gorilla gorilla gorilla) to be particularly reactive to large crowds, the evidence of these effects is mixed, and is likely highly influenced by exhibit design, and group composition. While the […]