both at the Murchison Falls National Park, Uganda
|Genus:|| Ourebia |
The oribi ( /ˈɔːrəbi/ ; Ourebia ourebi) is a small antelope found in eastern, southern and western Africa. The sole member of its genus, it was described by the German zoologist Eberhard August Wilhelm von Zimmermann in 1783. While this is the only member in the genus Ourebia, eight subspecies are identified. The oribi reaches nearly 50–67 centimetres (20–26 in) at the shoulder and weighs 12–22 kilograms (26–49 lb). It possesses a slightly raised back, and long neck and limbs. The glossy, yellowish to rufous brown coat contrasts with the white chin, throat, underparts and rump. Only males possess horns; the thin, straight horns, 8–18 centimetres (3.1–7.1 in) long, are smooth at the tips and ringed at the base.
Typically diurnal, the oribi is active mainly during the day. Small herds of up to four members are common; males defend their group's territory, 25–100 hectares (62–247 acres) large. It is primarily a grazer, and prefers fresh grasses but also browses occasionally. A seasonal breeder, the time when mating occurs varies geographically. Unlike all other small antelopes, oribi can exhibit three types of mating systems, depending on the habitat – polyandry, polygyny and polygynandry. Gestation lasts for six to seven months, following which a single calf is born; births peak from November to December in southern Africa. Weaning takes place at four to five months.
The oribi occurs in a variety of habitats – from savannahs, floodplains and tropical grasslands with 10–100 centimetres (3.9–39.4 in) tall grasses to montane grasslands at low altitudes, up to 2,000 metres (6,600 ft) above the sea level. This antelope is highly sporadic in distribution, ranging from Senegal in the west to Ethiopia and Eritrea in the east and southward to Angola and the Eastern Cape (South Africa). The oribi has been classified as Least Concern by the IUCN; numbers have declined due to agricultural expansion and competition from livestock.
The scientific name of the oribi is Ourebia ourebi. The sole member of its genus, the oribi is placed under the family Bovidae. The species was first described by the German zoologist Eberhard August Wilhelm von Zimmermann in 1782.  It was formerly included in the tribe Neotragini, that comprised a variety of other dwarf antelopes, including Dorcatragus (beira), Madoqua (dik dik), Neotragus , Oreotragus (klipspringer) and Raphicerus . In 1963, German mammalogist Theodor Haltenorth separated the oribi and Raphicerus into a new tribe, Raphicerini; later on, zoologist Jonathan Kingdon assigned the oribi to Ourebini, a tribe of its own.  The common name "oribi" comes from the Afrikaans name for the animal, oorbietjie.  
In a revision of the phylogeny of the tribe Antilopini on the basis of nuclear and mitochondrial data in 2013, Eva Verena Bärmann (of the University of Cambridge) and colleagues showed that the oribi is the sister taxon to all other antilopines. The cladogram below is based on the 2013 study. 
The following eight subspecies are identified:   
Of these, zoologists Colin Groves and Peter Grubb identify O. o. hastata, O. o. montana, O. o. ourebi and O. o. quadriscopa as independent species in their 2011 publication Ungulate Taxonomy. 
The oribi is a small, slender antelope; it reaches nearly 50–67 centimetres (20–26 in) at the shoulder and weighs 12–22 kilograms (26–49 lb). The head-and-body length is typically between 92 and 110 centimetres (36 and 43 in).  Sexually dimorphic, males are slightly smaller than females (except for O. o. ourebi, in which females are smaller).  This antelope features a slightly raised back, and long neck and limbs. The glossy, yellowish to rufous brown coat contrasts with the white chin, throat, underparts and rump. The bushy tail, brown to black on the outside, has white insides   (except in O. o. hastata, that has a completely black tail). The subspecies show some variation in colouration; O. o. ourebi is a rich rufous, while O. o. hastata is yellower. 
Only males possess horns; the thin, straight horns, 8–18 centimetres (3.1–7.1 in) long, are smooth at the tips and ringed at the base.   The maximum horn length, 19.1 centimetres (7.5 in), was recorded in 1998 from Malawi.  The oribi has at least six different, well-developed scent glands (such as the prominent preorbital glands near the eyes). The body has several modifications, such as the large fossae below the eyes, to accommodate such a large number of glands.  Females have four teats. 
The oribi is diurnal (active mainly during the day), though some activity may also be observed at night.  It rests in cover during rain events. Unlike all other small antelopes, oribi can exhibit three types of mating systems, depending on the habitat – polyandry, polygyny and polygynandry;  polygyny tends to prevail as the female-to-male ratio increases.  A study suggested that polygyny is preferred in areas of high predator risk, as it leads to formation of groups as an anti-predator measure.  Small herds of up to four members are also common. 
Males defend their group's territory, 25–100 hectares (62–247 acres) large; female members may also show some aggression and drive away intruders. A study showed that the number of females that visit the male's territory depends on the appearance (particularly the symmetry) of the male's horns.  Males mark vegetation and soil in their territories by preorbital gland secretions and excrement; the intensity of marking increases with the number of male neighbours.   Dominant males tend to have greater access to females in and around the territory than other males.  An important feature of the social behaviour of oribi is the "dung ceremony", in which all animals form temporary dung middens. Oribi at least three months old have been observed giving out one to three alarm whistles on sensing danger. These whistles are more common in adults than in juveniles, and males appear to whistle more.   Common predators include carnivorans such as jackals. 
Primarily a grazer, the oribi prefers fresh grasses and browses occasionally. Grasses can constitute up to 90% of the diet; preferred varieties include Andropogon , Eulalia , Hyparrhenia , Loudetia , Pennisetum and Themeda species. Mineral licks are also visited regularly. Oribi have been observed feeding on flowers and Boletus mushrooms. Groups of oribi congregate in the rainy season, when grasses are abundant.  
Both sexes become sexually mature at 10 to 14 months. A seasonal breeder, the time when mating occurs varies geographically. Mating may peak in the rainy season (August to September).  When a female enters oestrus (which lasts for four to six days), she seeks the company of males. During courtship, the male will pursue the female, test her urine to check if she is in oestrus and lick her rump and flanks.  Gestation lasts for six to seven months, following which a single calf is born; births peak from November to December in southern Africa. The newborn is kept in concealment for nearly a month; the mother pays regular visits to her calf to suckle it for nearly half an hour. Males may guard their offspring from predators and keep away other males. Weaning takes place at four to five months.  The oribi lives for 8 to 12 years in the wild, and for 12 to 14 years in captivity. 
The oribi occurs in a variety of habitats – from savannahs, floodplains and tropical grasslands with 10–100 centimetres (3.9–39.4 in) tall grasses to montane grasslands at low altitudes, up to 2,000 metres (6,600 ft) above the sea level. Recently burnt areas often attract groups of oribi.   The choice of habitat depends on the availability of cover needed to escape the eyes of predators. Population densities typically vary between 2 and 10 individuals per km2; however, densities as high as 45 individuals per km2 have been recorded in tropical grasslands that receive over 110 centimetres (43 in) of annual rainfall and open floodplains. The oribi's range overlaps with those of larger grazers such as the African buffalo, hippopotamus, hartebeest, Thomson's gazelle and topi. These separate species often occur in close proximity to each other, increasing predator vigilance.  
This antelope is highly sporadic in distribution; it occurs mainly in eastern, southern and western Africa, ranging from Nigeria and Senegal in the west to Ethiopia and Eritrea in the east and southward to Angola and the Eastern Cape (South Africa).  It is feared to be extinct in Burundi. 
The oribi has been classified as Least Concern by the IUCN. The total population (as of 2008) is estimated at 750,000.  However, the subspecies O. o. haggardi is listed as Vulnerable because, as of 2008, the total population is estimated at less than 10,000 mature individuals, and is feared to be declining. Hunting is a relatively minor threat, since the oribi shows some tolerance to hunting. Nevertheless, the steep fall of 92% in oribi populations in Comoé National Park (Côte d'Ivoire) has been attributed to poaching. Numbers have also declined due to agricultural expansion and competition from livestock.  
The oribi occurs in a number of protected areas throughout its range, such as: Gashaka Gumti National Park in Nigeria, the Pendjari and W National Parks (Benin); Aouk Hunting Zone (Chad); Benoue, Bouba Njida and Faro National Parks (Cameroon); Manovo-Gounda St. Floris National Park (Central African Republic); Garamba, Upemba and Kundelungu National Parks (Congo-Kinshasa); Omo National Park (Ethiopia); Masai Mara Game Reserve and Ruma National Park (Kenya); Golden Gate Highlands National Park (South Africa); Serengeti National Park (Tanzania); Kidepo Valley, Lake Mburo and Murchison Falls National Parks (Uganda); Kafue and Liuwa Plain National Parks and Bangweulu Swamp (Zambia).  
The term antelope is used to refer to many species of even-toed ruminant that are indigenous to various regions in Africa and Eurasia.
The klipspringer is a small antelope found in eastern and southern Africa. The sole member of its genus and subfamily/tribe, the klipspringer was first described by German zoologist Eberhard August Wilhelm von Zimmermann in 1783. The klipspringer is a small, sturdy antelope; it reaches 43–60 centimetres at the shoulder and weighs from 8 to 18 kilograms. The coat of the klipspringer, yellowish gray to reddish brown, acts as an efficient camouflage in its rocky habitat. Unlike most other antelopes, the klipspringer has a thick and coarse coat with hollow, brittle hairs. The horns, short and spiky, typically measure 7.5–9 cm.
The sitatunga, sometimes called the marshbuck, is a swamp-dwelling medium-sized antelope found throughout central Africa, centering on the Democratic Republic of the Congo, the Republic of the Congo, Cameroon, parts of Southern Sudan, Equatorial Guinea, Burundi, Ghana, Botswana, Rwanda, Zambia, Gabon, the Central African Republic, Tanzania, Uganda and Kenya. The sitatunga is mostly confined to swampy and marshy habitats. Here they occur in tall and dense vegetation as well as seasonal swamps, marshy clearings in forests, riparian thickets and mangrove swamps.
The common eland, also known as the southern eland or eland antelope, is a large-sized savannah and plains antelope found in East and Southern Africa. It is a species of the family Bovidae and genus Taurotragus. An adult male is around 1.6 m (5.2 ft) tall at the shoulder and can weigh up to 942 kg (2,077 lb) with a typical range of 500–600 kg (1,100–1,300 lb), 340–445 kg (750–981 lb) for females). It is the second-largest antelope in the world, being slightly smaller on average than the giant eland. It was scientifically described by Peter Simon Pallas in 1766.
The giant eland, also known as the Lord Derby's eland and greater eland, is an open-forest and savanna antelope. A species of the family Bovidae and genus Taurotragus, it was described in 1847 by John Edward Gray. The giant eland is the largest species of antelope, with a body length ranging from 220–290 cm (87–114 in). There are two subspecies: T. d. derbianus and T. d. gigas.
The hirola, also called the Hunter's hartebeest or Hunter's antelope, is a critically endangered antelope species found on the border between Kenya and Somalia. It was first described by the big game hunter and zoologist H.C.V. Hunter in 1888. It is the only living member of the genus Beatragus, though other species are known from the fossil record. The global hirola population is estimated at 300–500 animals and there are none in captivity. According to a document produced by the International Union for Conservation of Nature "the loss of the hirola would be the first extinction of a mammalian genus on mainland Africa in modern human history".
The common tsessebe or sassaby is the southern, nominate subspecies of Damaliscus lunatus, although some authorities have recognised it as an independent species. It is most closely related to the Bangweulu tsessebe, sometimes also seen as a separate species, less to the topi, korrigum, coastal topi and tiang subspecies of D. lunatus, and less to the bontebok in the same genus. Common tsessebe are found in Angola, Zambia, Namibia, Botswana, Zimbabwe, Eswatini, and South Africa.
The hartebeest, also known as kongoni or kaama, is an African antelope. It is the only member of the genus Alcelaphus. Eight subspecies have been described, including two sometimes considered to be independent species. A large antelope, the hartebeest stands just over 1 m at the shoulder, and has a typical head-and-body length of 200 to 250 cm. The weight ranges from 100 to 200 kg. It has a particularly elongated forehead and oddly-shaped horns, a short neck, and pointed ears. Its legs, which often have black markings, are unusually long. The coat is generally short and shiny. Coat colour varies by the subspecies, from the sandy brown of the western hartebeest to the chocolate brown of the Swayne's hartebeest. Both sexes of all subspecies have horns, with those of females being more slender. Horns can reach lengths of 45–70 cm (18–28 in). Apart from its long face, the large chest and the sharply sloping back differentiate the hartebeest from other antelopes. A conspicuous hump over the shoulders is due to the long dorsal processes of the vertebrae in this region.
The puku is a medium-sized antelope found in wet grasslands in southern Democratic Republic of Congo, Namibia, Tanzania, Zambia and more concentrated in the Okavango Delta in Botswana. Nearly one-third of all puku are found in protected areas, zoos, and national parks due to their diminishing habitat.
The royal antelope is a West African antelope recognized as the world's smallest antelope. It was first described by Swedish zoologist Carl Linnaeus in 1758. It stands up to merely 25 cm (10 in) at the shoulder and weighs 2.5–3 kg (5.5–6.6 lb). A characteristic feature is the long and slender legs, with the hindlegs twice as long as the forelegs. Horns are possessed only by males; the short, smooth, spiky horns measure 2.5–3 cm (0.98–1.18 in) and bend backward. The soft coat is reddish to golden brown, in sharp contrast with the white ventral parts. In comparison to Bates's pygmy antelope, the royal antelope has a longer muzzle, broader lips, a smaller mouth and smaller cheek muscles.
The blue duiker is a small antelope found in central, southern and eastern Africa. It is the smallest species of duiker. The species was first described by Swedish naturalist Carl Peter Thunberg in 1789. 12 subspecies are identified. The blue duiker reaches 32–41 centimetres (13–16 in) at the shoulder and weighs 3.5–9 kilograms (7.7–19.8 lb). Sexually dimorphic, the females are slightly larger than the males. The dark tail measures slightly above 10 centimetres (3.9 in). It has short, spiky horns, around 5 centimetres (2.0 in) long and hidden in hair tufts. The subspecies show a great degree of variation in their colouration. The blue duiker bears a significant resemblance to Maxwell's duiker.
The bohor reedbuck is an antelope native to central Africa. The animal is placed under the genus Redunca and in the family Bovidae. It was first described by German zoologist and botanist Peter Simon Pallas in 1767. The bohor reedbuck has five subspecies. The head-and-body length of this medium-sized antelope is typically between 100–135 cm (39–53 in). Males reach approximately 75–89 cm (30–35 in) at the shoulder, while females reach 69–76 cm (27–30 in). Males typically weigh 43–65 kg (95–143 lb) and females 35–45 kg (77–99 lb). This sturdily built antelope has a yellow to grayish brown coat. Only the males possess horns which measure about 25–35 cm (9.8–13.8 in) long.
Thomson's gazelle is one of the best known species of gazelles. It is named after explorer Joseph Thomson and is sometimes referred to as a "tommie". It is considered by some to be a subspecies of the red-fronted gazelle and was formerly considered a member of the genus Gazella within the subgenus Eudorcas, before Eudorcas was elevated to genus status.
The Suni is a small antelope. It occurs in dense underbrush from central Kenya to KwaZulu-Natal in South Africa.
The dibatag, or Clarke's gazelle, is a medium-sized slender antelope native to Ethiopia and Somalia. Though not a true gazelle, it is similarly marked, with long legs and neck. It is often confused with the gerenuk due to their striking resemblance. The typical head-and-body length is about 103 to 117 cm. They stand up to about 80 to 90 cm. Male dibatag weigh between 20 and 35 kg, whereas females range from 22 and 29 kg. The length of the curved horns, present only on males, is typically between 10 and 25 cm. The upper parts are gray to fawn, while the dorsal and lateral areas are cinnamon to rufous. The underparts, rump and the insides of the legs are all white. While markings are visible on the face, there are none on the flanks or the buttocks.
The Maxwell's duiker is a small antelope found in western Africa.
The red-flanked duiker is a species of small antelope found in western and central Africa in countries as far apart as Senegal and Sudan. Red-flanked duikers grow to almost 15 in (35 cm) in height and weigh up to 31 lb (14 kg). They have russet coats, with greyish-black legs and backs, and white underbellies. They feed on leaves, fallen fruits, seeds and flowers, and sometimes twigs and shoots. The adults are territorial, living in savannah and lightly wooded habitats, and the females usually produce a single offspring each year. They have lifespans of ten to fifteen years in captivity.
The southern reedbuck, rietbok or common reedbuck is a diurnal antelope typically found in southern Africa. It was first described by Pieter Boddaert, a Dutch physician and naturalist, in 1785. It is placed in the genus Redunca and family Bovidae. This antelope has an average mass of 58 kg (128 lb) and a body length of about 134–167 cm (53–66 in).
Damaliscus lunatus is a large African antelope of the genus Damaliscus and subfamily Alcelaphinae in the family Bovidae, with a number of recognised geographic subspecies. Some authorities have split the different populations of the species into different species, although this is seen as controversial. Common names include topi, sassaby, tiang and tsessebe
The steenbok is a common small antelope of southern and eastern Africa. It is sometimes known as the steinbuck or steinbok.