 = Oribi = 
 
 Oribi ( pronounced / ˈȯrəbē / ) ( Ourebia ourebi ) is a small antelope found in eastern , southern and western Africa . The sole member of its genus , the oribi was first described by the German zoologist Eberhard August Wilhelm von Zimmermann in 1782 . 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 ) . 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 . 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 . The oribi is primarily a grazer , and prefers fresh grasses and 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 . 
 
 = = Taxonomy = = 
 
 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 . The oribi 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 " ( pronounced / ˈȯrəbē / ) 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 . 
 
 = = Description = = 
 
 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 . 
 
 = = Ecology and behaviour = = 
 
 The oribi is diurnal ( active mainly during the day ) , though some activity may also be observed at night . The animal 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 . 
 
 = = = Diet = = = 
 
 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 . 
 
 = = = Reproduction = = = 
 
 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 ) , it 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 . 
 
 = = Distribution and habitat = = 
 
 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 . 
 
 = = Threats and conservation = = 
 
 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 ) . 
 
 