Blue monkey Uganda is a common and adaptable forest primate found across Uganda’s forest zone, the olive-grey coat and white throat patch making it a familiar sight on forest walks in Bwindi and Kibale. The blue monkey is a forest guenon that is actually dark grey with a blackish face, crown and legs, and a long dark tail. Despite the name, it only looks bluish in some light. It is common in Uganda’s forests, including Kibale, Bwindi, Budongo, Semuliki and the Rwenzoris, and is one of the monkeys most often seen on gorilla and chimp treks.

Blue Monkey Uganda: Bwindi and Kibale Resident Facts

Habits

Blue monkeys live in groups of females and young with a single adult male, usually 10 to 40 animals. They eat fruit, leaves, flowers and insects, and spend most of their time in the middle and upper canopy. They often travel with red-tailed monkeys and other species, which helps all of them spot predators. Crowned eagles are among their main enemies.

Hybrids in Kibale

In Kibale, blue monkeys and red-tailed monkeys sometimes interbreed, producing hybrid young with mixed features. This happens where one species is scarce and males of the other join its groups. It is one of the best-known examples of hybridisation among wild monkeys.

Where to see it

Look in the canopy during chimp treks in Kibale and gorilla treks in Bwindi, and on forest walks at Budongo. The gorilla permit costs US$800, or US$600 in April, May and November. See our guides to Kibale Forest, Bwindi, the red-tailed monkey and Kibale animals.

Frequently asked questions

Distribution in Uganda

The blue monkey (Cercopithecus mitis) is one of Uganda’s most widespread forest primates, occurring in Kibale, Bwindi, Budongo, and most forest patches in the western and central regions. It is more tolerant of forest degradation and secondary growth than many forest primates and occurs in plantation edges, riverine strips, and forest fragments outside national parks. Groups of 10 to 40 animals are regularly seen on forest walks and gorilla trekking trails throughout western Uganda.

Behaviour and Ecology

Despite its name, the blue monkey appears grey-olive to brown in most lighting conditions — the ‘blue’ refers to the lack of red and yellow pigmentation in the fur, giving a cool grey-blue appearance in certain light. The species is primarily frugivorous, supplemented by young leaves, insects, and flowers. Blue monkeys frequently associate with red-tailed monkeys and other species in mixed-species feeding groups. Like L’Hoest’s monkeys, they are preyed upon by crowned hawk-eagles and respond to eagle alarm calls immediately.

Conservation Status

The blue monkey is classified as Least Concern by the IUCN and is abundant across its range in sub-Saharan Africa. Uganda’s forest park populations are stable.

Viewing in Uganda

Blue monkeys are among the most commonly encountered primates on Kibale National Park forest walks, Bwindi gorilla trekking trails, and the Bigodi Wetland Sanctuary walk. The species is usually bold enough to observe at close range and is a reliable photographic subject in forest clearings and at forest edges where light allows good visibility.

Blue Monkey: Mixed Species Flocks

Blue monkeys frequently join multi-species primate aggregations at productive fruiting trees in Uganda’s forests, and these aggregations — sometimes involving blue monkeys, red-tailed monkeys, grey-cheeked mangabeys, and black-and-white colobus simultaneously in the same tree — are one of the most spectacular primate experiences in East Africa. The aggregations form when a large fruiting tree in prime condition attracts all the local primate groups, which tolerate each other’s presence in the resource-rich environment better than they would under normal circumstances. Kibale’s forest walks regularly produce these multi-species encounters. Guides who know the current fruiting activity in the forest can position groups near productive trees in advance.

The blue monkey is classified as Least Concern by the IUCN and is the most widely distributed forest monkey in Uganda, present across all major forest national parks. In Bwindi, blue monkeys are encountered on gorilla trekking trails and forest walks in all sectors. The species is tolerant of selective logging and secondary forest and persists in forest fragments outside national parks, though with lower density. Blue monkey social groups are typically composed of one adult male and multiple females with young; the solitary bachelor males that leave birth groups are occasionally seen alone, their dark face and slate-blue fur making them distinctive even without the social group context.