Other Primates in Diani

Abstracted from information compiled by R. Eley and P. Kahumbu -- The colobus isn't the only primate in Diani.  In fact, there are three primate families on the south coast at Diani: 1.) Family Lorisinae (bushbabies), 2.) Family Cercopithecidae (vervets, sykes, baboons, colobus) and 3.) Family Hominidae (humans).

   Vervet Monkeys   
Cercopithecus aethiops

Cercopithecus monkeys are the most common monkeys found in Africa. Five of the 20+ species found in Africa can be found in Kenya and both the Vervet and Sykes monkeys can be found commonly in Diani. The Vervet (also known as the "African green monkey") is a grey-brown monkey with white under parts, white-fringed black face, long whitish cheek whiskers, white brow, black feet and black tip of the tail. Males posses a blue scrotum, red penis and red peri-anus and weigh around 4 to 6 kg and measure 40 to 60 cm when adult. Females are normally 2 to 5 kg and measure 30 to 50 cm. Female breasts also often have a bluish tinge to them. Infants have similar, but lighter, colouration and also have pink faces.
Normally found in savannah, woodland, riverine, lake-shore and coastal forests - Vervets normally do not inhabit heavily forested areas of very open grasslands. They are widely distributed around southern Africa (south of the Sahara Desert) and are found throughout Kenya - even in the city of Nairobi!

Vervets are omnivorous, opportunistic feeders eating fruit, seeds, roots, bark, flowers, gum, insects, small vertebrates and eggs. In Diani, tourist tid-bits provide a healthy portion of many Vervets' daily diet and all visitors are warned not to feed them. Although they adapt easily to new situations and seem tame when used to human feeding, they are still wild animals and are treated as such. This includes being disease carriers, rabies and other bite diseases and could result in the animals being put down.

Vervets are equally at home on the ground and in the trees, and this flexibility is reflected in their distribution. They live within troops of 20 to 30 animals with a linear dominance hierarchy among males, and (like baboons) a kinship relationship among females. Complex communication among Vervets has been documents for some time, with characteristic and different calls being contextual for different sorts of situations and eliciting different responses in return. For example, alarm calls for aerial predators differ from alarm calls for snakes are different - requiring the Vervets in the area to look in different places to triangulate the danger.
 

   Sykes Monkeys   
Cercopithecus albogularis

Sykes monkeys are also widely distributed on the Kenyan coast and are a common sight in Diani. They are approximately the same size as a Vervet, ranging from 50 to 70 cm in body length and weighing 6 to 9 kg for males and 3 to 6 kg for females.
Their colour is largely grey, with a blackish tail, limbs and shoulders, and a distinctive flecked chestnut back and face. They have a white chin and throat and a white ruff which extends part of the way around the neck. The forehead hairs point forward, creating a yet more distinctive look. Infants are similar, but with a slightly darker coat and pink face.

Skyes monkeys are arboreal and found in all sorts of heavily wooded areas, including the coast. They are omnivorous, although their main food is leaves, shoots, flowers, fruits and berries. They will also feed on birds eggs, insects and other food like human food - for which they are notorious and sly thieves.

Skyes monkeys are highly territorial and live in female bonded, single-male troops (averaging 20 individuals in Diani) although they tend to forage in a more dispersed manner. Sykes troops are remarkably stable and peaceful groups, with resident males maintaining dominance for years on end and sub-adult males being evicted readily. Outsider males often learn to imitate the dominant male's call to lure away females. Interestingly enough, these monkeys sometimes associate with the colobus, grooming and playing with each other at times, especially juveniles. It is thought that the colobus tolerate the Sykes monkeys because they are extremely vigilant and are usually first to notice any danger.

Skyes monkeys also make a curious assortment of vocalisations, from soft bird-like chirping to trilling sounds given by sub-adults as a sign of submission when approaching an adult. Loud chirps and bird-like alarm calls bring the troop into a state of alertness. Growls and screams are emitted during chases between troop members and a series of puled calls are given in alarm to birds of prey.
 

   Yellow Baboons   
Papio cynocephalus

Baboons belong to the genus Papio which is divided into five species - Olive, Yellow, Chacma, Guinea and Hamadryas - of which the Olive and Yellow are found in Kenya. Baboons are monkeys (although they are often wrongly referred to as apes) and are not threatened although their numbers have been declining in Africa overall in the recent years because of eradication programmes.
The Yellow baboon is a mainly terrestrial, coastal baboon with yellow-brown hair, barrel chests, a prominent muzzle, naked face, large cheek pouches and close-set, amber-coloured eyes. They back legs are shorter then their front legs, giving them a characteristic backward sloping stance - and they often climb trees for food and as a place to sleep. They walk on their fingers and the soles of their feet.

Baboon infants are born black with pink faces, hands and ears, but turn brown in colour with darker faces with older age, usually beginning at about six months of age. Both males and females have large, grey-skinned sitting pads called "ischial" callosites (separated in females but joined in males). Females have pronounced sexual swellings between the sitting pads during estrus which is quite normal.

A mature male baboon is an imposing sight, weighing 20-30 kg and a head-body length of 70 cm, standing 50 cm at the shoulders. Males are approximately twice the size and weight of females. Apart from colour, the two Kenyan species of baboon are very similar in appearance, although the thinner coats of the Yellow baboon vs. the thick hair/manes of the Olive baboon make it look smaller in comparison. It takes males around seven to eight years to reach maturity, although they will continue to grow for a few years after that as well. Females reach sexual maturity at five years.

The primary habitat of the Yellow baboons is the savannah, but these highly opportunistic and adaptive animals can survive almost anywhere. In Kenya they occupy many habitats and have flourished in the Diani area. They naturally eat roots and bulbs, grasses, herbs, flowers, buds, fruits and leaves - as well as catch insects and are known to prey on rodents, rabbits and birds. In Diani and other populated areas, their diet extends to human food and they are notorious raiders of crops and garbage.

They also live in complex social societies made up of multi-male and multi-female troops, ranging in size from 10 to even 200 individuals. Each troop occupies a home range which varies in size from 2 square km in heavily wooded areas to 30 square km in more open areas. Baboons are extremely noisy creatures as well, communicating through an array of sounds accompanied by gestures and postures. They are known in Diani to make loud and boisterous displays daily, at dawn and at dusk.
 

   Bush Babies   
Galago senegalensis (Northern lesser)
Otolemur crassicaudatus (Thick-tailed greater)

Galagos (or as they are more commonly known "Bush babies") are found in most forested and wooded areas in sub-Saharan Africa. They are also only found in Africa. In Diani, they frequent gardens and kitchens during the night, searching for food.
They are small, nocturnal animals with very large eyes and excellent senses of hearing and smell. Their muzzles are pointed and they have mobile ears and long bush tails and more teeth than Old World monkeys (36 teeth for Bush babies, as opposed to 32). They additionally have extremely delicate fingers and extreme gripping power by pads on their fingers and toes - although on the ground their locomotion more resembles the kangaroo, jumping and pausing to look around. Bush babies diet varies slightly from place to place, but normally comprises - in the Greater - a mixture of insects, small reptiles and plant products and - in the Lesser - includes fruit. Prey is caught by pouncing and biting.

They are extremely social creatures and enjoy frequent interactions among each other, both of like and opposite sex. This is despite having exclusive ranges of from 1 to 3 hectares which thy guard and mark with urine, smeared on hands and feet, nightly. Bush babies are seasonal breeders and reach sexual maturity from age 1 to 2. Young are similar to adults although newborn Bush babies are naked on the underside for a period of approximately 1 week. For the first few months, baby Bush babies have been seen to be carried by their mothers in their mouths, similar to the behaviour of the domestic cat.