Meet the L’hoest monkey in Nyungwe forest

The L’Hoest’s monkeys are also referred to as the mountain monkeys or Cercopithecus lhoesti. They are guenon s commonly found in the montane forests in Albertine Rift regions which include places like the southwestern parts of Uganda, in Rwanda and Burundi as well as in the Democratic Republic of the Congo.  They prefer residing in the montane tropical rainforests, both the primary and secondary forests. So while in the secondary forests, normally they occupy those very thick underbrush which grows in places where the trees have fallen. L’Hoest’s monkeys mainly live in groups and in places with altitudes that range from 900- 2,500 m, this monkey is basically the most terrestrial monkey compared to any other guenons. These are a must see during your Safari in Rwanda

Physical appearance

L’Hoest’s monkeys are relatively large in size with a dark coat. They have a striking pattern monkeys with quite long limbs and tail. The females can weigh about 3.5 kg, while the males are often larger therefore can weigh up to 6 kg. Their body is mostly covered by that short dark gray fur and a big chestnut saddle pattern around the back area.

Around the throat is a large and unique striking white beard, its patch of fluffy fur running down the throat and cutting across both sides of its head almost reaching the ears. The rest of the body is dark as the limbs and belly region is black, most parts of the face are dark except the paler pinkish-white rings around their eyes and noses. The tail is gray but turns black towards its tip and they often bends their tails forward.    The eyes have that very bright orange color but among the males, the scrotum is usually bright blue but generally both females and males are similarly tinted. For perfect movement around in the jungle, they narrow feet to enable them to run properly. They also have cheek pouches which are very useful when they need to carry some food especially while foraging.

Maturity and reproduction

The L’Hoest’s monkeys are so polygamous in nature in a way that one male monkey lives and also mates with so many females. The moment a male reaches its sexual maturity, he will have to leave the group and assume independence and at that time, they are looking out for the mature female. The mature females have a signal, once they are really ready to meet the male, they start directing their behind toward the males and this behavior is called presenting.

After they have mate and the female L’Hoest’s monkey has conceived, she will have a gestation period of 5 months after which she will give birth to normally 1 offspring. They mainly give birth towards the end of a dry season every year. At birth, the infants are delivered with eyes open and their bodies are fully covered with that brown fur which only turns dark as they get older, color starts changing when they turn 2 or 3 months old. The mother will nurse its infant until another is born although they stop caring so much about their little ones after some few months. Weaning however occurs when the infant is about 1 year old.

When the mother gives birth, her little L’Hoest’s will clings onto its mother’s belly and also the other females in their group will want to hold this newly born infant. This parental care from other group members is probably because of the fact that these social groups usually comprise of blood related females and their young ones.

How they live/ behavior and Lifespan

In group of L’Hoest’s monkeys, there is usually only 1 male while the females may be 10 – 17 in number and young ones, all of them are often related. They always go hunting for food and to sleep in the trees as a group. As group, they participate in the mutual grooming thereby strengthening their bond between group members.                 L’hoest seldom interact with the other guenons in the forest. They spend most of their time on the ground and they may also flee from danger like predators while still on the ground rather than climbing up the trees which is a rare character among primates.

L’hoest monkeys can also live in captivity. At the moment, their life span while in the jungle is not yet unknown however, while in captive, this monkey can live for 24.1 years.

How they communicate

Because the L’Hoest’s monkeys need to flee from heir predators from the ground, they need proper coordination for their own safety. In other matters for example when females need to mate, they start directing their behind towards the males for them to see and this is a signal that the males understand. At some point, they do stare and this involves fixing the eyes that single object, they raise eyebrows, stretch their facial skin, and move the ears back. There are times when they open their mouth without displaying their teeth and sometimes they engage in head-bobbing, which goes along with staring the with opening the mouth when threatened.

What they feed on

L’Hoest’s monkeys are herbivores, they mainly feed on fruits, leaves, and small invertebrates but they contribute less than half their diet 50% of their diet consists of fruits and plant materials.  They also feed on mushrooms, herbs, and arthropods which they find in the shallow streams, they look for small fruits, fresh young leaves with more protein, buds and flowers as well as herbaceous stems. L’Hoest’s monkeys prefer fruits from particular plants. And they feed on particular invertebrates like insects, different ants. Earth worms, the spiders and also grasshoppers.

Predators and life threatening situations

L’Hoest’s monkeys’ lives are threatened by the common chimpanzees which on many occasions have killed the L’hoest. There are also the crowned hawk-eagles which prey on guenons, they do not exclude the L’Hoest’s monkeys. So to be able to escape the eagles, they have to flee while on the ground. Other predators include the humans who hunt them for bush meat.

Their impact on the ecosystem and humans

They are very good at seed dispersing since they are semi-frugivorous, the seeds they take in while eating fruits are dispersed elsewhere when they defecate.

To the humans, the L’Hoest’s monkeys are a source of food in form of bush meat.

L’Hoest monkeys can also spread diseases to humans because they are sometimes infected with a virus called Simian Immunodeficiency or SIV which changes into HIV when transmitted to human beings.

L’Hoest’s monkeys are among those really vulnerable primates on the red list of the ICUN. Their populations are currently declining because of a number of factors like deforestation for human activities like settlement, hunting, among others.

For more information about Destination Rwanda, visit gorillasafarirwanda.com