PRIMATE PROFILE

he tiny (200-gram) Somali Bushbaby, or Somali (Galago gallarum), Tlives in drier habitats than any other Life in the Thornbush – African … in Commiphora and Acacia thornbush where annual rainfall is low (< 600 mm), where drinking water is seldom available, and where there are often the Somali Bushbaby fewer than five bush and tree species. While the Vervet Monkey (Chlorocebus by Yvonne de Jong and Tom Butynski pygerythrus), Patas Monkey (Erythrocebus patas), and Yellow Baboon (Papio cyno- primate present. We have found this Bushbaby and Senegal Bushbaby. We cephalus) often forage in dry habitats, they species to be especially common at some mention three of these behavioural differ- all depend on the year-around availability of sites in Meru National Park and near ences here. First, the Somali Bushbaby is surface water… which they drink every day Moyale on the Kenya/Ethiopia border. much more confiding and altogether less or two. The Somali Bushbaby has no such In the field, the Somali Bushbaby is one shy than the Senegal Bushbaby. On being requirement, as it has adopted a ‘moisture- of the easiest Bushbabies to distinguish. It located with a spot lamp, the Somali saving’ nocturnal lifestyle… meeting its has the following combination of characters, Bushbaby frequently moves towards the water needs from the food that it eats. which make it unlike any other Bushbaby in observer… often to within five metres and As mentioned in a recent article in Kenya: a whitish face, blackish-brown eye sometimes to one metre. We often saw the Swara (‘Leapers in the Dark’, Vol 27:1, pp. rings and tail, and black ears. The fur of the Somali Bushbaby ‘using’ the bright light 50-51, 2004), Bushbaby has back is light buff. At night, in the light of a from our spot lamp to forage on the insects recently undergone some major changes… spot lamp, the dark eye rings, ears and tail the light attracted. The Senegal Bushbaby is and more big changes are expected. As contrast sharply with the pale face and body. generally shier, usually moving away from Bushbabies are nocturnal, natural selection The Senegal Bushbaby sometimes the observer once detected. for interspecific recognition has worked occurs in the same places as the Somali mainly on vocalisations and scent… rather Bushbaby, but can be distinguished by its econd, we observed (once) a mother than on visual external characters (for greyish back and ears. In our experience, Somali Bushbaby carrying her young example, the colour pattern of the pelage). the single best character for distinguishing Son the fur of her belly. Senegal As such, species of Bushbabies often these two species is the colour of the Bushbabies (indeed all other Bushbabies) resemble one another in their external ears… grey and pinkish in the case of the have been seen to carry young only in their physical appearance. To the ‘visually Senegal Bushbaby, jet black in the case of mouths. orientated’ human, this means that dis- the Somali Bushbaby. Third, unlike other species of tinguishing species of Bushbabies based Somali Bushbabies move at speed Bushbabies, we have yet to observe the on appearance has often been difficult. through the thorniest vegetation, making Somali Bushbaby making nests or entering Now, after more detailed studies of leaps of up to 2.5 metres between branches. holes to sleep. Instead, they sleep within Bushbaby vocalisations, morphology and They also come to the ground, where they very dense clumps of thorns or in aban- genetics, new ‘cryptic’ species have come hop on their hind legs between bushes and doned bird nests located among dense to light. For example, detailed studies of the trees. Little is known about the diet of the thorns. It seems likely that none of the ‘Senegal Bushbaby’ (Galago senegalensis) Somali Bushbaby. We have seen them feed many potential predators (such as snakes, have revealed that what was long thought to on gum and insects, and strongly suspect jackals, mongooses, genets, wild cats, be one species with many subspecies is in that they seasonally eat fruits as well. and raptors) would have much success in fact at least seven species… one of which All our observations to date of the capturing this highly mobile galago while it is the Somali Bushbaby. Our own recent, Somali Bushbaby have been of solitary is within these thorny retreats. preliminary research has revealed that the , or of two or three animals within The Somali Bushbaby remains one of Somali Bushbaby is a distinctive species about five metres of one another. Like other Africa’s least known . Given the with a vocal repertoire, aspects of behav- Bushbabies, the Somali Bushbaby has its extremely arid, species-poor habitats in iour, and habitat requirements that are own distinctive advertisement call… which which the Somali Bushbaby lives, it is different from any other Bushbaby species. we have named the ‘quack’. This call is expected to possess a number of unique The Somali Bushbaby occurs in the most frequently given within an hour after (if not surprising) behavioural, ecological, species-poor thornbush habitats of north- dusk and during the hour prior to dawn. The and physiological adaptations. eastern Kenya, southern Ethiopia, and ‘quack’ – probably an aid in long-distance As such, detailed, long-term studies of Somalia, but the limits of its distribution spacing and territoriality – is audible to the the Somali Bushbaby should be especially remain poorly understood. In Kenya, the human ear at distances as far away as 300 rewarding and enlightening… further Somali Bushbaby is known from east and metres. expanding the already quite astonishing north of the Tana River. Within its range, To date we have detected several range of adaptations found among the

Photos: © YVONNE DE JONG the Somali Bushbaby is often the only behavioural differences between the Somali Bushbabies.