The largest of the gibbons. Siamangs are tree-dwelling and extremely agile, despite their size.

They swing between branches and may walk upright on stronger tree boughs. They can cover 8 - 10 m (26 - 33 ft) between one grasp and the next in this fashion.

Families communicate by short barks and a distinctive whooping call, which is amplified by the inflatable throat sac.

Distribution: Peninsular Malaysia and Sumatra.

Habitat: Mountain forest

Food: Leaves, fruit, flowers, buds and insects.

Size: 75 - 90 cm (30 - 36 in); 8-13 kg (17 - 29 lb).

Maturity: 8 - 9 years.

Breeding: Single young born every 2 - 3 years.

Life span: 40 years.


The bonobo’s alternative name of pygmy chimpanzee is thought to refer to the stature of the native people in the area in which it is found. Social by nature, these chimpanzees keep in touch when they are on the move with a variety of calls, some of which have been likened to words in terms of their specific meanings.

A gregarious animal, the pygmy chimpanzee lives in a family group, and several families may gather in a good feeding area. Otherwise its habits are much the same as those of the chimpanzee.

The female bears 1 young, which stays with her for up to 3.5 years.

Distribution: Central Congo.

Habitat: Rain forest.

Food: Mostly fruit, occasionally leaves and seeds, rarely invertebrates.

Size: 70 - 83 cm (27.3 - 32.75 in); 27 - 61 kg (60 - 135 lb).

Maturity: 9 years.

Breeding: Single young, or occasionally twins, born every 3 - 6 years after a gestation of 225 - 235 days.

Life span: Probably similar to that of the closely related chimpanzee.

Cebidae: New World Monkeys

Most of the New World monkeys of the family Cebidae are much larger in size than any of the marmosets and tamarins — the other group of flat-nosed (platyrrhine) American monkeys. There are about 43 species, including capuchins, howler monkeys, sakis and uakaris. Typically these monkeys have long, hairy tails, which in some species are prehensile and of great importance in arboreal locomotion.

With a few exceptions, cebid monkeys conform to the flatnosed appearance so characteristic of New World monkeys. The nostrils are wide apart and open to the sides; they are a major distinguishing feature between New and Old World monkeys which have nostrils placed close together and opening forward. The long, thin fingers of the hands are useful manipulative organs and bear strong nails. Thus equipped, cebid monkeys are excellent leapers in wooded habitats in South America, from Mexico in the north to Argentina in the south. Diet is largely vegetarian.

Monk Saki

These monkeys are found in north-western Brazil, Colombia, Ecuador and Peru. Because they live at the very tops of rainforest trees, they are very difficult to study. Monk sakis are most active during the day. They leap from tree to tree in search of fruits, which they cut up with their long canine teeth before eating them.

Monk sakis live in small family groups of about four or five. Each group contains an adult breeding pair and their offspring of varying ages. A newborn saki clings to its mother’s belly. As it grows larger, it rides on her back, until it is able to move around independently.

Saki monkeys have very thick tails for their relatively small bodies. The tail is not prehensile and is used for balance. There is a gap between the second and third digit on both the front and rear feet.

Members of the family communicate using calls, mainly to let each other know where they are. At night, several families will sleep together in the same tree.

Distribution: Northern South America.

Habitat: Forest.

Food: Fruit, seeds, nuts and insects.

Size: 30 - 50 cm (12 - 19.5 in); 1 - 2 kg (2.2 - 4.5 lb).

Maturity: Unknown.

Breeding: 1 young born every year.

Life span: 12 - 25 years.

Status: Lower risk.

Cercopithecidae: Old World Monkey Family

The monkeys and apes of the Old World are usually grouped together as the catarrhine primates — those with closely spaced nostrils that face forward or downward. The Old World monkeys themselves are the largest group of catarrhines, with about 80 species known, in Africa, Asia and Indonesia. There are a few general differences between Old and New World monkeys. The first species are generally larger and their tails, although they are often long, are seldom, if ever, fully prehensile.

The family includes the macaques, baboons, mandrills, mangabeys, guenons, langurs, colobus and leaf monkeys and many other forms. Almost all are daytime-active animals. Most are arboreal, but baboons are ground-feeding specialists. Generally these monkeys live in family or larger groups and communicate by a variety of visual and vocal signals. Males are often considerably larger than females.

Blue Monkey

Most blue monkeys live in the rainforests of the Congo Basin, although they are also found in other habitats farther afield in southern and eastern Africa. Blue monkeys occupy humid places that have plenty of tall trees and a lot of running water available.

Male blue monkeys are also have more white facial hair. A single male rules a blue monkey troop, which can contain up to 40 members. The males in an area compete for ranks and only the highest-ranking alpha male mates with the troop’s mature females, which come into season at any time throughout the year. The females pout over their shoulder at the male during mating. Alpha males are frequently deposed by younger males moving up the ranks.

Blue monkey troops are very aggressive toward each other. The alpha male leads an attack by the grown males, but the females also join in. Interestingly, blue monkey troops will team up with a group of another species, such as its close relative the black-cheeked white-nosed monkey, to defend an area from other troops and predators. The two species forage for food in different parts of the forest, so they do not compete for resources. Both benefit from working together to keep hold of the territory.

Only a few blue monkeys are actually blue. Most have dark coloured fur with just a faint bluish tinge to the hairs around the face. Blue monkeys are also called diademed monkeys because of the tiara-shaped triangle of white fur on their heads. There are six subspecies of blue monkey.

Distribution: Central, eastern and southern Africa. Most common in Congo.

Habitat: Forest.

Food: Fruits and leaves.

Size: 65 cm (25.5 in); 6 kg (13.25 lb).

Maturity: 3 years.

Breeding: Each female produces a single young each year. Birth occurs at all times of the year. A single male fathers all the young in a troop.

Life span: 20 years.

Status: Vulnerable.


Male mandrills are large and heavily built with an long snout marked with deep, often colorful ridges. Adult females are much smaller and have less pronounced facial ridges and coloration. Mandrills sleep in trees, but live and feed on the ground in troops of about 20 to 50 animals, led by 1 or more old males.

Distribution: Southern Cameroon, Equatorial Guinea, Gabon and Congo.

Habitat: Forest.

Food: Mostly fruit, nuts and other vegetable material, and also invertebrates and occasionally small mammals.

Size: 61 - 76 cm (24 - 30 in); 30 - 54 kg (66 - 120 lb).

Maturity: Females 3.5 years; males probably much older.

Breeding: Single young born each year.

Life span: 45 years.

Agile Mangabey

Range: Africa: S.E. Nigeria, Zaire to E. Kenya.

Habitat: Rain and swamp forest.

Size: Body: 17 3/4 - 25 1/2 in (45 - 65 cm). Tail: 17 3/4 - 29 1/2 in (45 - 75 cm).

This is a slender, but strongly built monkey. The agile mangabey has long legs and tail and a fringe of hairs on its forehead. There are several races, which vary slightly in coloration, one has no fringe on the forehead.

The details of this mangabeys daily habits are poorly known, but it is thought to be active on the ground and in trees and to feed on leaves, fruit, crops and insects.

It lives in troops of 12 to 20 animals, consisting of several old males, mature females and their young.

White-cheeked Mangabey

Range: Africa: Cameroon to Uganda, Kenya, Tanzania.

Habitat: Forest.

Size: Body: 18 - 27 1/2 in (45 - 70 cm). Tail: 27 in—3 1/4 ft (70 cm - 1 m).

A slender, elegant monkey, the white cheeked mangabey is distinguished by its conspicuous eyebrow tuffs and the mane of long hairs. Its semi-prehensile tail is immensely long and mobile and covered with rather shaggy hairs.

These mangabeys sleep and spend nearly all their time in trees; they feed during the day on fruit, nuts, leaves, bark and insects. Troops of 10 to 30 animals live together and are extremely noisy, constantly chattering and shrieking to one another across the tree tops.

Grey-cheeked Mangabey

Size: 72 cm (28.25 in); 11 kg (24.25 lb).

Grey-cheeked mangabeys are also known as black mangabeys. Most of their body is covered in dark fur, though the facial hairs and shaggy mantle are considerably paler. Males are about 20 per cent larger than the females. Both sexes have very long tails that are slightly prehensile. (This characteristic is unusual for an Old World monkey. It is the American monkeys that are most known for this feature.) Grey-cheeked mangabeys inhabit the lowland rainforests. They live in small groups and each group has just one male. Most of their diet is fruits and nuts.

Black-cheeked White-nosed Monkey

The black-cheeked white-nosed monkey lives in forests across central and southern Africa. They are most common in Uganda, but populations are further south and west.

This species is primarily a rainforest monkey but it can survive in more open habitats as long as there is enough food. The monkeys are fruit eaters but they also consume resins, gums and insects.

The black-cheeked white-nosed monkey's name explains this species' most obvious features. Another of its common names is the redtail monkey, which refers to the chestnut-brown colouring on the underside of the tail.

Black-cheeked white-nosed monkeys live in groups run by a single male. The group forages and sleeps together. The group travels an average of 1.4 km (1 mile) every day. Like many similar monkeys, members of this species often store food inside their cheek pouches. This allows them to carry food to a place where they can eat it safe from attack by predators or from being stolen by other monkeys. Black-cheeked white-nosed monkeys often live alongside leaf-eating monkeys and so do not compete with them for food.

Distribution: Central and southern Africa.

Habitat: Forests.

Food: Fruits, insects and gums.

Size: 38 - 46 cm (15 - 18 in); 3 - 4 kg (6.5 - 8.75 lb).

Maturity: 4 - 6 years.

Breeding: Mating peaks in November to February.

Life span: 30 years.

Status: Common.

De Brazza's Monkey

Range: Africa: Cameroon, south to Angola, east to Uganda.

Habitat: Rain and swamp forest, dry mountain forest near water.

Size: Body: 15 3/4 - 23 1/2 in (40 - 60 cm). Tail: 20 3/4 - 33 1/2 in (53 - 85 cm).

The robust, heavily built De Brazza’s monkey has a conspicuous reddish-brown band, bordered with black, on its forehead, and a well-developed white beard. Its back slopes upward to the tail so that the rump is higher than the shoulders. Females look similar to males, but are smaller. Active during the day, this monkey is a good climber and swimmer and also moves with speed and agility on the ground, where it spends a good deal of its feeding time. Leaves, shoots, fruit, berries, insects and lizards are its main foods, and it will also raid crops. It lives in small family groups comprising an old male and several females with young. Sometimes there are larger troops of 30 or more animals.

After a week, the baby first starts to leave the safety of its mother body, and by 3 weeks, it is starting to climb and run.

Red-bellied Guenon

Range: Africa: Nigeria.

Habitat: Forest.

Size: Body: about 18 in (45 cm). Tail: about 23 1/2 in (60 cm).

This apparently rare monkey has a dark face with a pinkish muzzle, fringed with white side-whiskers. The breast and belly are usually reddish-brown, hence the common name, but can be gray in some individuals. Females look similar to males but have grayish underparts, arms and legs. Few specimens of this monkey have been found, and its habits are not known.

Allen's Swamp Monkey

These monkeys are found only in swamp forest: areas of low-lying tropical forest that are frequently flooded. In the case of Allen’s swamp monkey, the swamps are fed by the Congo River. When the river breaks its banks and spills across the forest floor, the monkeys climb into trees for safety. During their time in the trees, the monkeys eat fruits and leaves.

Once the flood has subsided, however, the monkeys descend to the muddy forest floor once again. Their webbed feet help them to walk over the mud as they search for worms, beetles and other invertebrates.

Allen's swamp monkey has slightly webbed fingers and toes to help it move through shallow swamps. The males are slightly larger than the females.

The webbing is also useful during floods. If a monkey is threatened while up a tree, the monkey’s first line of defence is to dive into the water, where it can swim away to safety. Allen’s swamp monkeys are preyed on by large hawks, snakes and bonobos, which also live in the swampy forests. This species is polyganous, and females develop a sexual swelling when on heat.

Distribution: Congo Basin.

Habitat: Swamp forest.

Food: Fruits, water plants and insects.

Size: 60 cm (23.5 in); 3.5 kg (7.75 lb).

Maturity: 3 - 5 years.

Breeding: Single young born to females at all times of year.

Life span: 20 years.

Status: Lower risk.

Owl-faced Monkey

Size: 40 - 65 cm (15.5 - 25.5 in); 4 - 10 kg (8.75 - 22 lb).

Owl-faced monkeys live in eastern Congo and southern Uganda. This species occupies bamboo forests that grow on the slopes of the Ruwenzori Mountains. The males are twice the weight of the females, but both sexes have similar olive-grey colouring. There is a pale yellow stripe running across the eyebrows and another crossing that one and running down to the upper lip. This T-shaped marking is the species' most obvious feature. The rump and genitals of both sexes are naked, with blue skin. Mature males sport a bright red penis, which stands out against the monkey's muted colouring. Owl-faced monkeys have extremely long fingers, which are used to grip smooth bamboo stems. (Bamboo grows in cold and wet locations, so the stems are also often slippery.) Owl-faced monkeys eat mainly bamboo shoots.

Diana Monkey

Range: Africa: Sierra Leone to Ghana.

Habitat: Rain forest.

Size: 55 cm (21.75 in); 7 kg (15.5 lb).

A slender, elegant monkey, the diana monkey has most striking coloration with its black and white face. There are also conspicuous white stripes on the otherwise dark hair of each thigh. Females are smaller than males, but in other respects look similar.

The Diana monkey is a resident of the forests of West Africa. They are found only in untouched rainforest, where they eat leaves, fruits and insects. As a consequence of their reliance on this habitat, Diana monkeys are vulnerable to extinction. They are mainly black. A white stripe also runs down the thighs. The back of the legs is orange. These patches are visible as flashes of colour as the monkey moves through the dense forest. Diana monkeys are polygynous (the males mate with several females in one season).

An excellent climber, the diana monkey spends virtually all its life in the middle and upper layers of the forest and is noisy and inquisitive. Troops of up to 30 animals live together, led by an old male. They are most active in the early morning and late afternoon, when they feed on leaves, fruit, buds and other plant matter, and also on some insects and birds’ eggs and young.

Mona Monkey

Size: 53 cm (20.75 in); 4 kg (8.75 lb).

Mona monkeys live in the rainforests of Central Africa. They range from Uganda in the east to Gambia in the west and Angola in the south. This species has also been introduced to the Caribbean island of Grenada. Mona monkeys are very colourful: they have red-brown fur on the back, the rump and front are white, while the face is blue with a pink snout. Mona monkeys live in small groups ruled by a single male. These small harem groups often band together into troops of about 50 monkeys.