Willem is a wildlife artist based in South Africa. He says "My aim is simply to express the beauty and wonder that is in Nature, and to heighten people's appreciation of plants, animals and the wilderness. Not everything I paint is African! Though I've never been there, I'm also fascinated by Asia and I've done paintings of Asian rhinos and birds as well. I may in future do some of European, Australian and American species too. I'm fascinated by wild things from all over the world! I mainly paint in watercolours. . . but actually many media including 'digital' paintings with the computer!"

I bring you another cute little crittur! This is a Greater Galago, in South Africa often known as a Thick-Tailed Bushbaby, Otolemur crassicaudatus. The scientific name means 'Thick-tailed Ear-Lemur'. This refers to this little monkoid's thick and fluffy tail, large ears, and its relationship to the lemurs of Madagascar. Galagos or Bushbabies only occur in Africa, in a great diversity of species, of which this is the largest. It appears to be about the size of a cat, but is actually much lighter, having a slender body underneath its thick fur. It reaches an overall length of a meter/yard, and a bodyweight of 2 kg/4.4 lbs, though 1.3 kg/2.9 lbs is more typical. The greater galago occurs in Africa south of the equator, in woodland, well-wooded savannah, coastal and riverine forest. I've once had one in my garden! It is not native to my region though … this was possibly an individual that had come in on a truck carrying fruit from a more well-wooded area.

You would be well-served to peruse this article on the South African Bushbaby for general information about galagos/bushbabies. Briefly: bushbabies are primates, relatives of monkeys, apes and ourselves, though more 'primitive' in the sense of still much resembling the very early primates of 50 million and more years ago. They're nocturnal and specialized for leaping from tree to tree, with lengthened foot bones and both hands and feet able to grasp. Their large eyes can't move much in their sockets, but their necks are very flexible, allowing them to turn their heads right round. Their ears are ribbed and can be folded down tight to their skulls to prevent damage when they creep into their tree holes where they sleep by day. They have comb-like lower front teeth, for grooming their thick, fluffy fur, and a toothed 'second tongue' called a denticle underneath the main body of their tongue, for cleaning the tooth comb. They also have sharp grooming claws on the second toes of their feet. They often eat the sweet gum that exudes from the damaged bark of thorn and other trees.

From the general bushbaby description above, greater galagos differ in various respects. They are less specifically adapted than other bushbabies, more like the general lemur-type of primate. They don't jump as well as the others. Mostly they climb and walk four-limbed on tree branches or on the ground. When alarmed on the ground, they may bound, or leap on their hind legs very reminiscent of the 'dancing' leaps of the Sifakas of Madagascar. I was fortunate enough to see this recently, on a trip to Venda. A couple of (probably male) thick-tailed bushbabies emerged from the forest making lots of noise; it looked like one was chasing the other. The chased one descended to the path on which we were walking, leaping towards us on its hind legs. It was more afraid of its challenger than of us, and continued leaping towards us until it was just a couple of yards away. Then it seemed to notice us, and leapt off the path back into the bushes. We watched it a bit longer as it settled in a tree and seemed to calm down; after sitting there a while it leaped away again.

Crybabies of the Forest

Greater galagos are very vocal. Firstly, they have the characteristic call from which all the bushbabies get their name. This loud, territorial call sounds like the crying of a highly distressed baby, and is a familiar sound in well-wooded regions of northern South Africa. The species has many other calls: squawks, whistles, cackles, gurgles, yaps, rattles, moans and clucks. Young ones accompanying their mothers on foraging trips make a buzzing sound when they fear they've lost contact with her.

Making Scents

Although they have very large, round eyes, vision is not the most important sense for greater galagos. On very dark nights in dense forests, there is not enough light for even the best of eyes to see well. Their huge ears come in handy, being able to be twisted and turned to pick up sounds up from various directions. But mainly, galagos rely on their sense of smell. Their snouts are wet much like those of dogs, the moisture enabling them to easily register scent chemicals. They themselves are founts of scented chemicals. They liberally use urine to scent-mark their territories, as well as scent from genital glands. They rub their hands and feet around their genital tracts, so that the scent comes off on their fingers and toes, from where it sticks to the branches and twigs as far as they move. They also have scent glands on their heels, depositing a different scent. The skin on the heels is also very rough and hard, making a grinding noise as they walk along branches, adding another auditory component by which individuals can sense each other's proximity. Members of family groups also deposit scent from lip glands and saliva onto each other by mutual grooming.

The main scent gland of the greater galago is on the chest, exuding an oily, yellow secretion. The galago rubs its chest on certain spots within its range, 'landmarks' of its territory. There are three different kinds of volatile chemical in the secretion, one of which fades away after about an hour, but the others which remain for days. A bushbaby coming across a place where another has deposited its scent, will take its time to sniff it carefully. They can identify each other individually by scent, and learn of each other's movements. Greater galagos are somewhat more social than others, often forming groups of a male and female with their offspring. Adult males will defend territories, which may slightly overlap those of other males. They sometimes allow other males into their territory, so long as those males respect their dominance. Mostly they avoid conflict by avoiding each other.

Finding Food

The savannahs and woodlands of Africa are seasonal, with rain restricted to the few months of summer, followed by long and severe droughts. Greater galagos prefer to eat the fruit and flowers of trees and shrubs, but this is mainly available during the spring, summer and autumn. To tide them over the dry winter months, they rely on tree gum. They nibble at the bark of gum-exuding trees; this will cause the gum to come out, which the galagos then eat. This gum is not very nutritious; it has carbohydrates, but practically no protein. The galagos thus supplement their gum diet with insects, such as moths or cicadas. Some galagos eat birds and their eggs, and small reptiles. They get their water directly from their food, or by licking dew off leaves.

Bushbaby Babies

Compared to other critturs I've treated here, greater galagos are rather sexy. They're promiscuous: when the female comes into oestrus, she seeks out several males. They've got stamina, making love for up to 49 uninterrupted minutes.

The female gives birth to one to three babies in a leafy nest up in a tree. They're born with eyes open and can move around. She nurses them in the nest; if it becomes necessary to move them, she carries them in her mouth. At the age of eight days, she can carry them clinging to the fur of her back. They leave the nest at around 21 days, and stop nursing at around ten weeks. They stay with their mother for 15 months or so, sometimes even longer. It is mainly the adult males that will leave first; the others stay together to form tight little family groups, bonding by grooming each other. They form 'sleeping groups' that snuggle together in tree cavities during the day.

Greater galagos are still widespread and common in suitable habitat; they're not persecuted by humans and face few threats other than habitat destruction.

Willem

20.01.20 Front Page

Back Issue Page