Gorilla Care Manual

The Effect of Positive Reinforcement Training on an Adult Female Western Lowland Gorilla’s (Gorilla gorilla gorilla) Rate of Abnormal and Aggressive Behavior

Positive reinforcement training (PRT) has become a widely used tool in improving the ease with which husbandry and veterinary procedures are performed for animals under human care. PRT provides positive social interaction, cognitive stimulation, and choice, in addition to desensitization towards potentially stressful situations. As a result, PRT has been used as enrichment to decrease […]

Living in nonbreeding groups: an alternative strategy for maturing gorillas

The one-male reproductive strategy implies that maturing males are temporarily excluded from reproduction. In gorillas, these excluded males live either solitarily or in nonbreeding groups (NBGs) that are devoid of adult females. The dynamics of NBGs are not well known. In this study, which was conducted on a gorilla population (Gorilla gorilla gorilla) of 377 […]

Behavioral response of captive western lowland gorillas (Gorilla gorilla gorilla) to the death of silverbacks in multi-male groups

Abstract 10.1002/zoo.20246.abs In both free-ranging and captive western lowland gorillas, a silverback provides protection and leadership, mediating conflict within a group. In the wild, when a dominant silverback dies the group will disperse or transfer to a solitary male, unless a subsequent male is present to inherit the group. In captivity, studies have focused on […]

Do gorillas regurgitate potentially-injurious stomach acid during ‘regurgitation and reingestion?’

Regurgitation and reingestion (R/R) of foodstuffs is a common abnormal behaviour in captive western lowland gorillas (Gorilla gorilla gorilla) and certain other non-human primates, but it is not part of their normal feeding mechanism. It is similar to a behavioural problem seen in humans, human rumination syndrome (HRS), which can occur in association with anxiety […]

Assessing inactivity in zoo gorillas using keeper ratings and behavioral data

One way to address the problem of small sample size in zoo research is to conduct a study involving multiple institutions. However, when conducting behavioral research, it can be difficult for one investigator to travel to each institution or for staff at individual institutions to find time to collect behavioral data. This study validates keeper […]

Assessing the prevalence and characteristics of hair-plucking behaviour in captive western lowland gorillas (Gorilla gorilla gorilla)

Non-human primates occasionally exhibit behaviours thought to occur only in captivity that are considered abnormal. In partic-ular, hair-plucking behaviour occurs across many species of mammals and birds. This study was the first to assess the phenom-enology, demography and aetiology of this behaviour in captive gorillas across the Association of Zoos and Aquariums (AZA) population. A […]

Assessing the prevalence and characteristics of hair-plucking behaviour in captive western lowland gorillas (Gorilla gorilla gorilla)

Non-human primates occasionally exhibit behaviours thought to occur only in captivity that are considered abnormal. In particular, hair-plucking behaviour occurs across many species of mammals and birds. This study was the first to assess the phenomenology, demography and aetiology of this behaviour in captive gorillas across the Association of Zoos and Aquariums (AZA) population. A […]

Implementing a low-starch biscuit-free diet in zoo gorillas: The impact on behavior

In the wild, western lowland gorillas travel long distances while foraging and consume a diet high in fiber and low in caloric density. In contrast, gorillas in zoos typically consume a diet that is low in fiber and calorically dense. Some items commonly used in captive gorilla diets contain high levels of starch and sugars, […]

Implementing a low-starch biscuit-free diet in zoo gorillas: The impact on health

In the wild, western lowland gorillas consume a diet high in fiber and low in caloric density. In contrast, many gorillas in zoos consume a diet that is high-calorie and low in fiber. Some items commonly used in captive gorilla diets contain high levels of starch and sugars, which are minimal in the natural diet […]