oribi

File:The book of antelopes (1894) Ourebia nigricaudata.png

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.{{MSW3|id=14200638|page=686}} 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.{{cite book|last1=Kingdon|first1=J.|author-link=Jonathan Kingdon|last2=Happold|first2=D.|last3=Butynski|first3=T.|last4=Hoffmann|first4=M.|last5=Happold|first5=M.|last6=Kalina|first6=J.|title=Mammals of Africa|date=2013|publisher=Bloomsbury Publishing Plc|location=London, UK|volume=6|isbn=978-1-4081-2257-0|pages=404–12|url={{Google Books|id=B_07noCPc4kC|page=RA4-PA404|plainurl=yes}}}} The common name "oribi" comes from the Afrikaans name for the animal, oorbietjie.{{MerriamWebsterDictionary|Oribi|access-date=24 April 2016}}

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.{{cite journal|last1=Bärmann|first1=E.V.|last2=Rössner|first2=G.E.|last3=Wörheide|first3=G.|title=A revised phylogeny of Antilopini (Bovidae, Artiodactyla) using combined mitochondrial and nuclear genes|journal=Molecular Phylogenetics and Evolution|year=2013|volume=67|issue=2|pages=484–93|doi=10.1016/j.ympev.2013.02.015|url=https://www.researchgate.net/publication/236042243|pmid=23485920|bibcode=2013MolPE..67..484B }} {{open access}}

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|1=Oribi (Ourebia ourebi)

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|1=Saiga (Saiga tatarica)

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|1=Gerenuk (Litocranius walleri)

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|1=Eudorcas

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|1=Gazella

|2=Blackbuck (Antilope cervicapra)

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|1=Procapra

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|1=Raphicerus

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|1=Madoqua

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The following eight subspecies are identified:{{ITIS|taxon=Ourebia ourebi|id=625112|access-date=23 April 2016}}{{cite book|last1=Skinner|first1=J.D.|last2=Chimimba|first2=C.T.|title=The Mammals of the Southern African Sub-region|date=2006|publisher=Cambridge University Press|location=Cambridge, UK|isbn=978-1-107-39405-6|pages=696–8|url={{Google Books|id=F23lAgAAQBAJ|page=696|plainurl=yes}}}}

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• O. o. dorcas Schwarz, 1914
• O. o. gallarum Blaine, 1913
• O. o. haggardi (Thomas, 1895) – Occurs in eastern Africa. Listed as Vulnerable by the IUCN.
• O. o. hastata (Peters, 1852) – Ranges from Kenya southward into Mozambique and eastward into Angola
• † O. o. kenyae Meinhertzhagen, 1905 – Occurred on the lower slopes of Mount Kenya.
• O. o. montana (Cretzschmar, 1826) – Ranges from northern Nigeria eastward into Ethiopia and southward into Uganda.
• O. o. ourebi (Zimmermann, 1783) – Its range lies south of Zambezi River.
• O. o. quadriscopa (C. H. Smith, 1827) – Occurs in western Africa
• O. o. rutila Blaine, 1922

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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.{{cite book|last1=Groves|first1=C.|author1-link=Colin Groves|last2=Grubb|first2=P.|author2-link=Peter Grubb (zoologist)|title=Ungulate Taxonomy|date=2011|publisher=Johns Hopkins University Press|location=Baltimore, USA|isbn=978-1-4214-0093-8|page=179}}

The oribi is a small, slender antelope; it reaches nearly {{convert|50|–|67|cm|in}} at the shoulder and weighs {{convert|12|–|22|kg|lb}}. The head-and-body length is typically between {{convert|92|and|110|cm|in}}.{{cite book|last1=Kingdon|first1=J.|title=The Kingdon Field Guide to African Mammals|date=2015|publisher=Bloomsbury Publishing Plc|location=London, UK|isbn=978-1-4729-2135-2|pages=573–4|edition=2nd|url={{Google Books|id=sjPCCAAAQBAJ|page=573|plainurl=yes}}}} 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{{cite web|title=Oribi Ourebia ourebi|url=http://www.ewt.org.za/species%20factsheets/Oribi.pdf|publisher=Endangered Wildlife Trust|access-date=2016-04-24|archive-date=2016-06-02|archive-url=https://web.archive.org/web/20160602205733/https://www.ewt.org.za/species%20factsheets/Oribi.pdf|url-status=dead}}{{cite book|last1=Mills|first1=G.|last2=Hes|first2=L.|title=The Complete Book of Southern African Mammals|date=1997|publisher=Struik Publishers|location=Cape Town, South Africa|isbn=978-0-947430-55-9|page=266|edition=1st|url={{Google Books|id=CavgCweI1nMC|page=266|plainurl=yes}}}} (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, {{convert|8|–|18|cm|in}} long, are smooth at the tips and ringed at the base. The maximum horn length, {{convert|19.1|cm|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.

File:Sudan Oribis (Ourebia montana) (18231586045).jpg

The oribi is diurnal (active mainly during the day), though some activity may also be observed at night.{{cite book|last1=Long|first1=J.L.|title=Introduced Mammals of the World: Their History, Distribution and Influence|date=2003|publisher=Csiro Publishing|location=Clayton, Australia|isbn=978-0-643-09916-6|page=485|url={{Google Books|id=7YC3cYhGMOcC|page=485|plainurl=yes}}}} 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.{{cite journal|last1=Arcese|first1=P.|last2=Jongejan|first2=G.|last3=Sinclair|first3=A.R.E.|title=Behavioural flexibility in a small African antelope: group size and composition in the oribi (Ourebia ourebi, Bovidae)|journal=Ethology|date=1995|volume=99|issue=1–2|pages=1–23|doi=10.1111/j.1439-0310.1995.tb01085.x|bibcode=1995Ethol..99....1A }} 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.{{cite journal|last1=Adamczak|first1=V.G.|last2=Dunbar|first2=R.I.M.|title=Variation in the mating system of oribi and its ecological determinants|journal=African Journal of Ecology|date=2008|volume=46|issue=2|pages=197–206|doi=10.1111/j.1365-2028.2007.00833.x|bibcode=2008AfJEc..46..197A }} Small herds of up to four members are also common.

Males defend their group's territory, {{convert|25|–|100|ha|acre}} 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.{{cite journal|last1=Arcese|first1=P.|title=Harem size and horn symmetry in oribi|journal=Animal Behaviour|date=1994|volume=48|issue=6|pages=1485–8|doi=10.1006/anbe.1994.1391|s2cid=53150077}} 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.{{cite journal|last1=Brashares|first1=J.S.|last2=Arcese|first2=P.|title=Scent marking in a territorial African antelope: I. The maintenance of borders between male oribi|journal=Animal Behaviour|date=1999|volume=57|issue=1|pages=1–10|doi=10.1006/anbe.1998.0941|pmid=10053066|s2cid=38863236|url=https://www.researchgate.net/publication/13237420}}{{cite journal|last1=Gosling|first1=L.M.|title=The construction of antorbital gland marking sites by male oribi (Ourebia ourebia, Zimmerman, 1783)|journal=Zeitschrift für Tierpsychologie|date=1972|volume=30|issue=3|pages=271–6|doi=10.1111/j.1439-0310.1972.tb00856.x|url=https://www.researchgate.net/publication/230026822}} Dominant males tend to have greater access to females in and around the territory than other males.{{cite journal|last1=Arcese|first1=P.|title=Effect of auxiliary males on territory ownership in the oribi and the attributes of multimale groups|journal=Animal Behaviour|date=1999|volume=57|issue=1|pages=61–71|doi=10.1006/anbe.1998.0962|pmid=10053072|s2cid=41424552}} 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.{{cite book|last1=Kingdon|first1=J.|author-link=Jonathan Kingdon|title=East African Mammals: An Atlas of Evolution in Africa|date=1984|publisher=University of Chicago Press|location=Chicago, USA|isbn=978-0-226-43718-7|page=222|url={{Google Books|id=x75kYjINSqUC|page=222|plainurl=yes}}}}

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.

File:Gazelles grass park w niger 2006.jpgs at W National Park, Niger]]

The oribi occurs in a variety of habitats – from savannahs, floodplains and tropical grasslands with {{convert|10|–|100|cm|in}} tall grasses to montane grasslands at low altitudes, up to {{convert|2000|m|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 {{convert|110|cm|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.{{cite journal|last1=Mduma|first1=S.A.R.|last2=Sinclair|first2=A.R.E.|title=The function of habitat selection by oribi in Serengeti, Tanzania|journal=African Journal of Ecology|date=1994|volume=32|issue=1|pages=16–29|doi=10.1111/j.1365-2028.1994.tb00551.x|bibcode=1994AfJEc..32...16M }}

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).{{cite book|last1=Mduma|first1=S.A.R.|editor1-last=Sinclair|editor1-first=A.R.E.|editor2-last=Arcese|editor2-first=P.|title=Serengeti II: Dynamics, Management, and Conservation of an Ecosystem|pages=220–31|chapter=Distribution and abundance of oribi, a small antelope|year=1995|publisher=University of Chicago Press|location=Chicago, USA|isbn=978-0-226-76032-2|url={{Google Books|id=YV5Qg2GSyWwC|page=220|plainurl=yes}}}} It is feared to be extinct in Burundi.{{cite book|last1=East|first1=R.|title=African Antelope Database 1998|date=1999|publisher=IUCN Species Survival Commission|location=Gland, Switzerland|isbn=978-2-8317-0477-7|pages=290–5|url={{Google Books|id=59Ci3C8BCmEC|page=290|plainurl=yes}}}}

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).

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{{Portal|Mammals|Animals|Africa}}

• {{commonscat-inline|Ourebia ourebi}}
• {{Wikispecies-inline|Ourebia ourebi}}

{{Artiodactyla|R.5}}

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Category:Dwarf antelopes

Category:Mammals of Sub-Saharan Africa

Category:Mammals described in 1783

Category:Taxa named by Eberhard August Wilhelm von Zimmermann