Bushbaby

© Roger de la Harpe

Name

Bushbaby (galagidae)
Lesser bushbaby (galago moholi)
Thick-tailed bushbaby (otolemur crassicaudatus)

Bushbabies, or galagos of Africa, are one of the smallest primates on the continent. Although they are rather common, they are difficult to spot due to being nocturnal. Their baby-like cries can often be heard during the night.

Lesser Bushbaby Appearance

Lesser bushbabies have rounded fingernails, except for the second toe which is used as a grooming claw to comb the head and neck fur, and to clean the ears. It has a tooth comb dental structure which also facilitates grooming. Its toes and fingers are padded with flat disks of thickened skin, providing grip in climbing trees and on slippery surfaces. The index finger on each paw is much shorter than the others, allowing a better grip on bigger branches. The coat of the lesser bushbaby varies from a brownish grey to a light brown. Its limbs and sides have a distinctly yellow hue, with a marking between the dark ringed eyes.

Lesser Bushbaby Diet

The lesser bushbaby licks dew and rainwater from cracks and crevices, and eats insects and tree gum.

Lesser Bushbaby Breeding

Lesser bushbabies generally give birth to twins after a 125 day gestation period, immediately followed by another oestrus cycle. They give birth before the rainy season, and well before the next dry season the next set of twins are born. At the peak of her oestrus cycle, a lesser bushbaby female will mate with up to six males. She will build nests for her infants to stay in while searching for food, and protect them from danger by carrying them away in her mouth. Male lesser bushbabies mark the females by urinating on them.

Lesser Bushbaby Behaviour

The lesser bushbaby is a small, nocturnal, tree-dwelling primate. They can make huge leaps between trees, but at times walk on the ground using all fours or their hind legs. Adult males avoid conflict and confrontation with one another by protecting their individual territories. Apart from this behavioural characteristic, their social systems and habits are similar to that of the thick-tailed bushbaby. Adults forage unaccompanied, but at night gather to interact and during the day to sleep in groups of six.

The lesser bushbaby has about 18 different calls which can identify different behaviours. Their calls communicate social contact, aggression and defensiveness, and is a vital survival strategy in recognising and warning of the enemy. Their hearing is highly developed, and their ears have intricate folds which allows them to locate the source of the sound accurately. The lesser bushbaby can hear the glide of an owl.

Their eyes are unable to move in their sockets, making their heads move constantly in search of prey. With extremely quick movements, they can catch moths and grasshoppers in the air with their front paws while gripping onto a branch with their hind legs. Before embarking on a night’s foraging expedition the lesser bushbaby will groom itself, being very particular of its appearance.

Lesser Bushbaby Habitat

Being a South African species, the lesser bushbaby has a high tolerance of temperature variation. It prefers savannas, woodlands, the fringes of the forest and riverine bush as its habitat, and in particular near the Limpopo River where the Marico and Notwani Rivers meet.

Where they are found

The lesser bushbaby ranges throughout the Southern African Region including South Africa, Namibia, Botswana, Mozambique, and Zimbabwe - as well as in Swaziland.
Lesser Bushbaby Predators

The lesser bushbaby has many predators, including larger species of owl, servals, snakes, African wild cats, and genets. However, their greatest threat is fire. Despite its ability to leap between trees, the lesser bushbaby is incapable of moving large distances at a time. They are therefore greatly affected if a fire destroys the food supply of their inhabited area. They are usually found in habitats of short and moist grass - a form of protection from fire.

Interesting Facts

Many African tribes are superstitious of the lesser bushbaby, attributing its baby-like cries and chattering noises to a mysterious, colourful giant snake with a feathered head, which kills evil trespassers by biting a hole in their head.

Thick-tailed Bushbaby Appearance

The thick-tailed bushbaby is the largest of the galago species. Its head and body measures from 297 to 373 mm, and its tail from 415 to 473 mm. Males are significantly larger than females.

Its coat is silvery brown to gray of colour, with a lighter underside. Its fur is thick, woolly, wavy and quite long. They tend to roll and unroll their ears, and with their large eyes give them a quizzical expression.

As with most galago species, the thick-tailed bushbaby has long finger and flattened toes and nails. The pads of thickened skin at the end of its fingers and toes gives grip in grabbing branches.

Thick-tailed Bushbaby Diet

Thick-tailed bushbabies are largely gumivorous and frugivorous, meaning they feed on the gum and saps of trees, insects and fruits. A study conducted in South Africa showed that their diet mainly consists of gums, supplemented by fruits and insects. However, the bushbabies of Kenya’s diet may consist of 50 to 70% insect, whereas in Gauteng insects compromise only 5% of their diet. The large termite (macrotermes falcigar) is the bushbaby’s seasonal food supply, and is eaten off the ground without the use of hands. Their diet generally consists of insects, fruit, leaves, lizards, eggs, birds and flowers.

Thick-tailed Bushbaby Breeding

The birth season of the thick-tailed bushbaby varies according to its locality. The oestrus cycle lasts about 44 days. In the Gauteng area, birth season is limited to November, whereas it occurs during August and September in Zambia. In Zanzibar and Pemba, pregnancies peak in August.

A litter of two, and sometimes three, is born after 133 days of gestation. While females go to forage, they leave their young in the tree. They produce a rich, energy-dense milk, particularly in comparison to the milk produced by other anthropoid primates. The richness of the thick-tailed bushbaby’s milk may be due to their habit of not carrying their young with them during lactation, as other anthropoid primates do. Nests are made for the young in the tangles of vegetation.

The thick-tailed bushbaby gives birth once a year when vegetation is dense. It has been reported from studies in captivity, however, that this species has continuous oestrus cycles and thereby able to give birth throughout the year. The young become independent of their mothers at the age of 4 to 5 weeks, and both males and females reach sexual maturity at about 20 months.

Thick-tailed Bushbaby Behaviour

The thick-tailed bushbaby is the most social of all known bushbabies, showing a social network without the structure of a foraging group. Unlike other galagines, they move through the forest and bush quadrupedally by hopping, and landing on their hind legs after jumping.

Being nocturnal, the thick-tailed bushbaby is active for 9.5 hours per day during summer, and 12 hours per day during winter. Males disperse from their birth territory at a younger age and further than females, fluctuating the male membership in populations more so than the female. This may be a habit to lessen complications of inbreeding. Thick-tailed bushbabies share their ranges with younger or older individuals, but not with those of their own age. Males are territorial and have home ranges which overlap with one or more females.

Females are dominant in this species. Studies conducted in captivity found that males are more likely to follow females, and females act aggressively towards them. In social play, they perform an exaggerated walk, chase, pull tails, wrestle, pounce and bite one another non-aggressively. When infants are independent from their mothers at about five weeks of age, they tend to play more.

Thick-tailed bushbabies sleep in nests 5 to 12 metres from the ground, and sleep there together during the day. At night, they split up to forage traversing about one kilometre through the night. They live in small groups of 2 to 6 individuals of varying compositions. A group could consist of an adult pair and their young, two adult females with young, or one adult female with young.

They have the habit of cupping their hands, depositing urine therein to spread on the soles of their feet. When walking, they mark their urine on the ground. This behaviour is seen more frequently in males, particularly when the female is in her oestrus cycle. The male, of all age classes, then urinates onto the female. Urine-washing occurs when the thick-tailed bushbaby is foraging in a new area, confronted with a strange object, during aggressive encounters, and in social grooming. Dominant individuals engage in this behaviour more frequently.

Where they are found

The thick-tailed bushbaby prefers highlands, coastal and riverine forests as its habitat. They are found in Somalia, Tanzania, Kenya, and on the Zanzibar islands. They also occur from east Africa, southern Sudan, southern Angola and eastern South Africa. Before 1974 only 6 species of bushbaby were recognised. By 1995, 17 species on the African continent gained recognition and more new species are likely to be discovered.