Common names: large-eared greater galago, Garnett’s greater galago, thick-tailed bushbaby, thick-tailed greater galago, greater bushbaby, greater galago (Eng.); bosnagaap Afr.).
The brown greater galago is a nocturnal primate that occurs in southern, central and East Africa in forests and savannas.
Description/How to recognize
Species from the genus Otolemur differs from other galago genera in having a large body size, which ranges from 800 to 1 500 g in adults. This species has two subspecies namely O.c. crassicaudatus and O.c. kirkii. Depending on the subspecies, the species has a long bushy tail that ranges from 29 to 55 cm; thus exceeding its head and body length that is 26–41 cm. It has a rounded head with very large ears and relatively large forward-facing eyes with binocular vision. It has a thick fur that varies considerably based on the subspecies and environment. It also has long, thin toes and fingers, which allows them to grip easily on to branches.
Getting around
Brown greater galago prefers to climb, walk or run instead of leaping as compared to smaller galago species
Communicating
Brown greater galagos communicate warnings visually by hanging their mouths open and folding their ears back. Their common name ‘bushbaby’ was derived from the fact that they make soft-clicking calls that sound like crying human infants and this particular call is unique to the brown greater galago. Additional calls include squeaks, barks, whistles and chirps.
They also communicate through scent. The most common behaviour is urine-washing, where they wash their feet in urine so that they can leave a trail scent wherever they go. They also rub the scent glands on their chest and genitals on branches in their territory.
Distribution
The brown greater galago is found throughout southern, eastern and Central Africa. The species has varying populations sizes in the west of Angola, down to South Africa in the south, as far east as the shores of Mozambique and as far north as Kenya. The subspecies has different distribution range with O.c. crassidautus found only in KwaZulu-Natal in South Africa, while O.c. kirkii is found in Mozambique and Malawi.
Habitat
They are mainly found in tropical and subtropical forests and even savannas. They prefer living near rivers and oceans in habitats rich with gum-producing trees. They can also occur in farmlands and urban gardens where fruit-bearing plants and other plants provide food and shelter.
Food
They feed on tree gum, flowers, nectar, insects and other small animals.
SEX and LIFE CYCLES
Females reach maturity earlier (16 months) than males (21 months). Brown greater galagos have a habitual breeding season that depends mainly on location. Breeding can occur as early as June to November; however, in South Africa, mating occurs in November. Regardless of the region, most mating seasons last for only a month and females has a gestation period of 133 days. The litter size is usually 1–3.
Brown greater galagos build a nest for their offspring where they keep them hidden when they search for food at night. The milk of brown greater galagos carries more nutrients that can nourish the young ones for longer periods of time and which make up for the limited feeding opportunities as mothers spend less time with their young compared to other primates. Juvenile galagos remains with the mothers until they are close to sexual maturity.
THE BIG PICTURE
Friends and Foes
Predators such as chimpanzees, snakes, leopards and birds of prey feeds on galagos.
Smart Strategies
For safety, the brown greater galago rests in higher areas (5–12 meters above the ground) in a dense tangle of creepers or in the hollow of a tree. They mark their territory by washing their feed with urine that leaves a trail scent wherever they go.
Poorer world without me
The most important role of the brown greater galago is insect control. They are one of a group of species that help keep the mosquito population under control.
People & I
These animals are occasionally hunted for traditional medicine, human consumption as bushmeat and for the illegal exotic pet trade. They are also threatened by the loss of habitat because of deforestation.
Conservation status and what the future holds
The brown greater galago is listed as Least Concern on the International Union for Conservation of Nature (IUCN) Red Data Lists.
Relatives
As members of the Order Primates, brown greater galagos are related to apes, monkeys and humans.
Official Common Name: Brown greater galago
Scientific Name and Classification:
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Primates
Family: Galagidae
Genus: Otolemur
Species: O. crassicaudatus É.Geoffroy, 1812
Derivation of scientific name: The genus name Otolemur, which means ’the eared-lemur’ was proposed by Coquerel (1859).
References and further reading
- Anderson, M.J. 2000. Penile morphology and classification of bush babies (Family Galagoninae). International Journal of Primatology 5,21: 815–836. doi:10.1023/A:1005542609002.
- Groves, C.P. 2001. Primate taxonomy. Smithsonian Institution Press, Washington, DC, USA.
- Happold, D. & Happold, M. 1992. Termites as food for the thick-tailed bushbaby (Otolemur crassicaudatus) in Malawi. Folia Primatologica, 58: 118–120.
- IUCN. 2019. The IUCN Red List of Threatened Species. Version 2019-3. Available at: www.iucnredlist.org.
- Masters, J. & Génin, F. 2016. A conservation assessment of Otolemur crassicaudatus. In Child, M.F., Roxburgh, L., Do Linh San, E., Raimondo, D., Davies-Mostert, H.T., eds. The Red List of Mammals of South Africa, Swaziland and Lesotho. South African National Biodiversity Institute and Endangered Wildlife Trust, South Africa.
- Whiting, M.J., Williams, V.L. & Hibbitts, T.J. 2011. Animals traded for traditional medicine at the Faraday Market in South Africa: species diversity and conservation implications. Journal of Zoology 284:84–96.
Author: Maphuti B. Ledwaba
E-mail: M.Ledwaba@sanbi.org.za