The Golden monkey is an insufficiently explored, but easily recognizable primate with a golden-orange patch on its upper flanks and back. This animal is an Old World monkey, endemic to Central Africa. In the past, the Golden monkey wasn't recognized as separate species, being considered a subspecies of the Blue monkey. In fact, these two monkeys are closely related and very similar. The ongoing divisions of forests has led to fragmentation of their range and Cercopithecus species have lived in isolated populations, where they have adapted to local environment. As a result, the Golden monkey has diverged from the Blue monkey. This endangered animal is one of the eight subspecies of the Blue monkey. Females of the golden monkey exhibit lighter coloration as well as less grizzled brown patches. However, there is very little information on the behavior and ecology of this species due to lack of observations.
The natural range of Golden monkey is limited to the Virunga volcanic mountains of Central Africa, where these animals occur in 4 national parks - Mgahinga (south-west Uganda), Volcanoes (north-west Rwanda), Virunga and Kahuzi-Biéga (eastern Democratic Republic of Congo). Ideal habitat for this species is highland forest with sufficient fruits and bamboo.
Golden monkeys are highly social animals, forming groups of 30 - 80 individuals. Each of these units is dominated by a single mature male. The group size varies with elevation; as a general rule, groups at higher elevations are smaller. Females are constantly with the group to defend the territory, whereas males usually remain with the group temporarily, leaving it after a while. These monkeys are diurnal and arboreal. Their sleeping sites are located at tops of bamboo plants. When sleeping, Golden monkeys gather into smaller groups of 4 individuals on average. Feeding areas are usually found in close proximity to their sleeping sites, so these animals take daily trips to forage. Primary forms of communication, used by these primates, are visual expressions and various vocalizations. Some of these vocalizations are used by males during confrontations or when defending their territories. Females of this species use a wide range of calls to keep unity of the group as well as alert community members of potential threats. Meanwhile, sub-adults are known to accompany mobbing behavior with certain calls. Additionally, young individuals may display submissiveness through vocalizations.
The Golden monkey is herbivore (folivores and frugivore), it generally feeds upon bamboo leaves, bamboo branchlets, bamboo shoots, fruits, flowers, and shrubs, supplementing this diet with occasional invertebrates such as the pupae of lepidopterous larvae, found on leaves.
Little is known about the mating system in Golden monkeys. However, as their groups consist of multiple females and only one male, it may mean that Golden monkeys may exhibit either polygynous or polygynandrous (promiscuous) mating systems. Although the male mates with all females of the group, mating is initiated by females. These primates are seasonal breeders. Gestation period lasts for 5 months, yielding one infant. Females give birth every two years. A newborn baby is well-developed. It comes with its total fur and open eyes. During the first few months, the baby is nursed by its mother. By the end of this period, the female gradually minimizes the nursing and eventually stops to produce a new young. Once becoming sexually mature, the baby will leave its natal group.
Most of threats to the population of this species are associated with human activity. Thus, the Golden monkeys suffer from habitat disturbance and are often caught in snares. These animals are also threatened by illegal destruction of their bamboo habitat.
The IUCN Red List and other sources don’t provide the number of the Golden monkeys’ total population. However, this species’ numbers are decreasing today, and the animal is classified as Endangered (EN) on the IUCN Red List.