Describer (Date):P.L. Sclater (1901) Proceedings of the Zoological
Society of London, 1901 vol. I p. 50
Kingdom: Animal Phylum: Chordata Class: Mammalia Order:
Artiodactyla* (nearly 200 species of even-toed, hoofed mammals) Suborder: Ruminantia (cud-chewing cattle, goats, sheep, bison, giraffes and more) Family: Giraffidae (only two species - giraffes and okapis) Genus:Giraffa camelopardalis (giraffe) Genus:Okapi (okapi) Species:Okapia johnstoni
*New anatomical and DNA evidence on the relationship between Artiodactyla (even-toed ungulates) and Cetacea (whales and dolphins) recently led to a merging of the two orders into a new group, Cetartiodactyla (Montgelard, 1997; reviewed in Kulemzina, 2009). As of October 2012, experts had not agreed on whether to define Cetartiodactyla as an official taxonomic order that would replace Artiodactyla and Cetacea. Some continue to list okapi in the order Artiodactyla (Franklin, 2011) or use the term Cetartiodactyla without defining it as an order (IUCN, 2008).
Common Names: okapi
Atti (from Wambuti pygmy tribe)
Okapi derived from the pygmy word O'Api which, when
spoken by pygmies, sounds like okapi.
Other Scientific Nomenclature:
Okapia liebrecht originated when, in the late 1800s,
Forsyth Major concluded that a specimen of skin and
skulls were a different species.
Okapia erikssoni was named in 1903 by Lord
Rothschild who found the skin of a female okapi to be
different. (note: both observations were false).
Okapi were unknown to western world (occupy dense African rainforest habitats) until discovered by Sir Harry Johnston in 1901. Species name is in Johnson's honor.
Taxonomy and Phylogeny.
Closest living okapi relative is the giraffe.
Some researchers dissent, pointing out that important differences in reproductive organs, fetuses, bile acid salts and skeletal anatomy make the okapi more likely to not belong in the giraffe family at all, but to be a closer relative of the nilgai antelope in the bovid (cattle) family. (Benirschke & Hagey 2006) (Spinage 1968)
Colbert (1938) made a detailed skeletal analysis of okapi and concluded that while they differed in many respects from giraffes, that they showed many primitive features of fossils of early giraffe relatives.
Giraffe family (giraffes and okapi) dates to about 15-12 million years ago (Miocene) (Dagg & Foster 1982).
Some two million years ago (Pleistocene) a now-extict okapi species (Okapia sp.) lived in East Africa in present-day Tanzania. At the same time in the same place, now extinct relatives of the giraffes existed.
Endemic to forests of Democratic Republic of Congo, occurring between about 500 m and 1,500 m elevation on both sides of the Congo River.
Okapi populations in the Ituri / Aruwimi and adjacent Nepoko basin forests, and the forests of the upper Lindi, Maiko and Tshopo Basins; also well known in the Rubi-Tele region in Bas Uele. (IUCN Redlist 2008)
Limited to closed, high canopy forests, occurring in a wide range of primary and older secondary forest types.
Okapi don't range into gallery forests or into forest islands on the savanna and they don't stay in the disturbed habitats surrounding human settlements.
Will occupy seasonally flooded areas when the ground is still wet, but they do not occur in truly wet sites or extensive swamp forest.
Tree fall gaps are selected foraging sites for okapi during the early stages of regeneration (Hart & Hart 1989).
Highly selective feeder on leaves, fruits, seeds, ferns, fungi of some 100 plant species.
Prefer to browse in small forest openings where fallen trees allow growth of light-dependent plants; prefer fast-growing tree seedlings, shrubs and vines
Okapi plants are only a temporary resource, scattered widely across the forests; most plants are not acceptable forage
Do not choose shade-tolerant shrubs and select only a small proportion of all the plants available.
Like giraffes, okapis use long, prehensile tongue to pull leaves off branches; a slender muzzle and flexible lips also help with choosing the "right" plants.
Also ingest clay for its minerals, burnt charcoal, and bat guano found in
Digestive system similar to other browsing ruminants.
As in giraffes, gall bladder not present.
Daily food intake (dry matter) of captive okapi ranges from 4.3-5.0 kg
REPRODUCTION & DEVELOPMENT
(Bodmer & Rabb 1992)
Female estrus cycles occur every 15 days throughout the year, but are
Males show few sexual hormonal fluctuations.
Males enter female home ranges to mate.
Males marking with urine occurs most frequently during courtship.
During courtship, couple stands head to tail in a reverse parallel
position, accompanied by circling and mutual sniffing of inguinal
areas. Males and females flehmen, and males then go through a series
of behaviors including head and neck stretches, head forward and
upward positions, erect postures, nose lifting, and leg kicking. The
receptive female responds by a head-low posture, often with the tail
Gestation lasts around 440 days.
Signs in females or impending birth are swelling of the udder, viscous
discharges from the vagina and swelling of the udder (swelling of the
udder may occur 2 months before the birth).
Females usually stand during birthing labor, but may recline for
Mother typically ingests the fetal membranes and placenta.
High frequency of contact and grooming between mother and infant after
birth. However, mothers may respond aggressively to the newborn,
striking with the head or hooves and sometimes killing the infant.
Litter Size: one (only one record of twinning)
Weigh 14-30 kg at birth; weight doubles by end of first month.
Okapi milk has 1/3 more protein than cow's milk and low fat content.
Okapi infants do not imprint strongly on mother and may nurse from more than one female at times.
Infants spend about 80% of time at the nest during the first 2 months
(this lack of activity may serve to ensure rapid growth).
Infants start taking solid food by the 3rd week, and rumination can be
seen by the 6th week.
Weaning takes place at 6 months, although young may continue to suckle
for > 1 year.
Horn development doesn't begin until about one year.
Adult size reached at about 3 years
Captive sexual maturity reached after 1 year 7 months (female) and 2
years 2 months (male).
Longevity of captives that survive past the 1st year is usually 15-20
years; exceptionally up to 33 years
POPULATION AND CONSERVATION STATUS
(Gijzen & Smet 1974) (Hart and Mwinyihali 2001) (IUCN Redlist 2008)
Okapi has become the flagship species for the conservation of the lturi ecosystem in the Congo Basin.
In Uganda, Okapi formerly occurred in the Semliki Forest, but is not known to survive there (IUCN Redlist 2008).
1925 Virunga National Park established; Africa's first national park.
A 2006 survey by local trackers and by World Wildlife Fund and its Congolese governmental partner ICCN (the Congo Institute for Nature Conservation), and the Gilman Conservation International found okapi signs in Virunga National Park in Eastern Congo after no sightings there since the 1950's.
In 2008 camera trap images of okapi obtained for first time; cameras set up in Virunga by Zoological Society of London and the Congolese Institute for Nature Conservation (ICCN).
1933: Okapi protection begins officially in Congo/Zaire.
1952: A captive breeding centre for okapi was first established at Epulu in the Ituri Forest, Zaire (now Democratic Republic of Congo or DRC)
1970: Maiko National Park established in DRC; it is not a World Heritage Site, but may have the most biodiversity of all the Congo's parks.
1987: Okapi Conservation Project begun by Gilman International Conservation to help protect native habitat in Ituri Forest of DRC.
1992: The Okapi Wildlife Reserve established
Occupies 13,700 square kilometers (5,290 square miles) in DRC
Is a Pleistocene refuge of exceptional species richness with a greater variety of mammals than any park in Africa:
15% of species are endemic which is one of the highest rates in the world
Until recently preserved only by its inaccessibility;
It has the highest known density of okapis known anywhere at approximately 2.5 animals per square kilometer (2. 5 per square mile)
1996: Okapi Wildlife Reserve designated as a United Nation World Heritage Site
Within the reserve, some 5,000 okapi are protected
This reserve encompasses the cultural center for two tribes of forest pygmy people - the Mubuti and Efe; okapi are not a significant part of their traditional diet,
Strengthening protection of this reserve and Maiko National Park is the single most important means to ensure long-term survival of Okapi (IUCN 2008)
1998: Okapi Wildlife Reserve placed on list of World Heritage in Danger because of devastation by civil war, invasion by miners and militants and destruction of wildlife by hunting for bushmeat and ivory.
2008: Report for World Heritage in Danger List: populations of the endemic okapi in Okapi Wildlife Reserve have decreased by 43 %, with a loss of an estimated 2,000 animals (http://cmsdata.iucn.org/downloads/drc___okapi___dec_32_com_7a.pdf
2009: Population estimates are quite imprecise but may be between 10,000 and 35,000 individuals.
IUCN status: (2009) Near Threatened
(version 3.1); population trend stable
Threats to Survival
Human population growth, settlement
Armed conflict/war/civil unrest/displaced human populations
(Hart and Mwinyihali 2001)
Other Web Resources
Okapi Conservation Project - managed by Institute in Congo for the Conservation of Nature (ICCN), oversees the Okapi Wildlife Reserve in the Democratic Republic of the Congo