|Scientific Name:||Okapia johnstoni (P.L. Sclater, 1901)|
Equus johnstoni P.L. Sclater, 1901
|Red List Category & Criteria:||Endangered A2abcd+4abcd ver 3.1|
|Assessor(s):||Mallon, D., Kümpel, N., Quinn, A., Shurter, S., Lukas, J., Hart, J.A., Mapilanga, J., Beyers, R. & Maisels, F.|
Okapi have been undergoing a decline since at least 1995 that is ongoing and projected to continue, in the face of severe, intensifying threats and lack of effective conservation action which is hindered by the lack of security. The rate of decline is estimated to have exceeded 50% over three generations (24 years), based on figures from surveys in the Okapi Wildlife Reserve (Réserve de Faune à Okapis; RFO) suggesting a 43% decline over the period 1995-2007, which some reports suggest continued in the period thereafter. The RFO remains the best protected site and it is inferred that the rate of decline here is at least equalled in other parts of the Okapi range. Although monitoring is only available to support estimates of declines in RFO since 1995, reports of declines or extirpations in other parts of the range and loss and degradation of habitat have been ongoing since 1980. The species is confirmed to be Endangered under criterion A2abcd+4abcd.
|Previously published Red List assessments:|
|Range Description:||Okapi distribution extends across parts of central, northern and eastern DR Congo. North and east of the Congo River, Okapi range from Maiko Forest north to the Ituri Forest, then west through the Rubi, Tele and Ebola river basins, extending north towards the Ubangi River. Okapi have a much smaller range to the west and south of the Congo River, extending from the west bank of the Lomami River west to the upper Lomela and Tshuapa basins (Hart 2013). In the fairly recent past, Okapi occurred occasionally in the adjoining Semliki forest of western Uganda (Kingdon 1979).|
Recorded presence is concentrated in and around protected areas, mainly reflecting survey effort. The remoteness and inaccessibility of much Okapi habitat make field work logistically difficult, and insecurity in DRC over the past two decades has further restricted survey activity. As a consequence, extensive parts of potential Okapi range are poorly studied. Furthermore, Okapi are secretive and their occurrence can easily go undetected, especially at low densities.
The known strongholds of the Okapi are the Ituri and Maiko landscapes, the forests of the upper Lindi, Maiko and Tshopo basins and the Rubi-Tele region in Bas Uele (Hart 2013). There are confirmed recent (2013) records of Okapi in the Abumonbanzi Reserve in Gbadolite district of North Ubangi at the northwest end of the distribution (Ngbolua et al. 2014).
Since 1980, expansion of human settlement, deforestation and forest degradation have eliminated important portions of the Okapi range, in particular in the southern and eastern Ituri Forest where the species was at one time abundant (Hart 2013).
The extent of occurrence (EOO) is 383,190 km2, but this includes unsuitable habitat such as degraded forest, swamp forest and urban areas. Excluding all these gives in an area of 244,405 km2 for the suitable or hypothesised range (Kümpel et al. 2015). The area of occupancy (AOO) is 14,112 km2, based on a grid of 5.6 x 5.6 km, the size used by most reported surveys and 450 (3.5%) of 12,764 grid squares with confirmed presence Kümpel et al. (2015). The AOO figure is however considered likely to be a substantial underestimate, surveys have been conducted in only 1,994 (15.6%) out of 12,764 grid squares so far.
Native:Congo, The Democratic Republic of the
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||East (1999) estimated that the total population may be over 10,000 and Hart (2013) estimated 35,000-50,000, though both sets of figures are perhaps better regarded as ‘guesstimates’ as they rely on extrapolation of a limited number of patchily distributed, dung-based surveys. Individual Okapi are rarely encountered and in much of their range they are uncommon or dispersed in localized areas, with dung found at low densities, commonly resulting in inadequate sample sizes for statistical analysis. Current numbers are believed to be lower and declining, but there is no reliable estimate of current population size. |
It is widely considered that there was a decline in the Okapi population, along with other species, following the decade-long civil war which ended in the early 2000s. Population estimates were made in the Okapi Wildlife Reserve (Réserve de Faune à Okapis; RFO) in 1993-1995 and repeated in 2005-2007 using the same ‘monitoring’ transects and distance sampling methodology, though individual transects were not necessarily carried out at the same time of year due to insecurity limiting access to parts of the Reserve (Hart et al. 2008). These surveys showed a decline in dung density of 43% between the two survey periods. A second set of transects in 2005-2007 used an improved spatial design (systematic placement of transects covering the entire reserve), but were also conducted across seasons for the reasons above. Further analysis is required to determine whether comparison of these ‘systematic’ transects with the 1995-1997 and 2005-2007 monitoring transects, and a further set of transects conducted in 2000-2002 over part of the reserve under the MIKE (Monitoring the Illegal Killing of Elephants) program, supports the observed decline in dung density, and to specifically investigate seasonality as a variable. The same type of systematic design was used again in 2010-2011, but implemented over the three month dry season to reduce the effects of seasonality. While an overall comparison between the two systematic surveys (2005-2007 and 2010-2011) appeared to show an increase in Okapi dung density (Vosper et al. 2012), a comparison between transects undertaken at the same time of year (the dry season only), in the same area of the reserve, showed no significant difference in Okapi dung density (F. Maisels pers. comm. 2014). Seasonal differences in dung decay rates therefore complicate comparisons between these various sets of surveys.
Supporting evidence for RFO is available from Law Enforcement Monitoring (LEM) patrols from 2008 to 2013. These patrols covered distances of 10,125–25,467 km annually and showed an apparent decline in Okapi dung encounter rates between 2008 and 2013 (ICCN RFO unpubl. data). However, because the patrols were focused on anti-poaching and wildlife recording was secondary, patrol routes were not randomly located, and patrol timings and locations varied among years because of security and logistical issues, the data must be interpreted with caution.
Since the rebel attack on the RFO headquarters in June 2012 (see ‘Threats’ below), the presence of armed groups and an influx of illegal miners and poachers has reduced the ability of the reserve authorities to protect the reserve and this is likely to have ongoing implications for resident wildlife populations. RFO is still the most effectively protected Okapi site with resident rangers and an active conservation programme and the overall rate of decline here is inferred to have been equalled or exceeded elsewhere.
In the Twabinga-Mundo region, anecdotal evidence suggests that Okapi are targeted for their skins and meat, and have undergone a drastic decline in numbers over the past two decades with local people reporting that Okapi is the most prized bushmeat available (Nixon 2010). Okapi had been present south of the town of Aketi and near the town of Buta but no signs were found on recent field surveys and locals said they had recently been hunted out by Bangalema nomadic hunters (Hicks 2010).
|Current Population Trend:||Decreasing|
|Habitat and Ecology:||Okapi are limited to closed, high canopy forests between about 450 m asl and 1,500 m asl and they occur in a wide range of primary and older secondary forest types. They do not extend into gallery forests or the forest-savannah ecotone and do not persist in disturbed habitats surrounding larger settlements. Okapi will use seasonally inundated areas when the substrate is still wet, but they do not occur in truly inundated sites or extensive swamp forest. Tree fall gaps are selected as foraging sites for Okapi during the early stages of regeneration (Hart 2013). Okapi are unique in being the only species of forest ungulate to depend on understorey foliage and they are known to feed on over 100 species. They are mainly diurnal but have also been recorded feeding at night (Nixon and Lusenge 2008). Okapi have defined but non-exclusive home ranges, averaging 3-5 km2 for adult females and up to 13 km2 for adult males. Okapi are mainly solitary (Hart 2013). Generation length is broadly estimated at around eight years, based on calculations made for the global captive population (S. Hofman and K. Leus pers. comm. 2013).|
|Continuing decline in area, extent and/or quality of habitat:||Yes|
|Generation Length (years):||8|
|Use and Trade:||Okapi are hunted for meat and skins.|
Okapi can coexist with small-scale, low-level human occupation of the forest, but disappear in areas of active settlement or disturbance, and the major threat to this species is habitat loss due to logging and human settlement including illegal occupation of protected areas (Hart 2013, Kümpel et al. 2015). According to Hart (2013) approximately one-third of the Okapi’s known distribution is likely to be at risk by major incursions during the first quarter of this century. Areas at high risk include the southeastern Ituri Forest, the Kisangani area, Rubi-Tele, and the western and eastern limits of the species' range in the Ebola River basin and Virunga-Hoyo region respectively.
Hunting for meat and skins is also a threat and Okapi decline rapidly in areas where there is persistent use of snares. In some areas, Okapi are targeted for bushmeat whereas in others they are taken only incidentally (Hart 2013, Kümpel et al. 2015).
The most prominent current threat to Okapi is the presence of illegal armed groups in and around key protected areas. These groups prevent effective conservation action, even surveys and monitoring in most sites, and engage in and facilitate elephant poaching, bushmeat hunting, illegal mining (gold, coltan and diamonds), illegal logging, charcoal production and agricultural encroachment. In a notorious incident in June 2012, armed rebels attacked the RFO HQ and killed seven people and all 14 captive Okapi.
This species is not included in the CITES Appendices. The Okapi is a fully protected species under Congolese law and the species is a national symbol, appearing on the insignia of the Institut Congolais pour la Conservation de la Nature (ICCN) and on Congolese banknotes.
Many captive Okapi are held in international collections. In November 2011, representatives of the North American and European captive populations, including the Okapi Species Survival Plan (SSP) and the Okapi European Endangered Species Programme (EEP), met to discuss the role of the captive population in Okapi conservation and agreed to maintain a sustainable, cooperatively managed global ex situ Okapi population that contributes to a viable in situ population (Petric 2012). The zoo community is a major supporter of Okapi conservation work, in 2010 donating USD 225,000 to the Okapi Conservation Project, 33% of its budget (Gilman International Conservation, 2010).
ICCN is the government agency responsible for protected area management but is under-staffed and under-funded. The Okapi Conservation Project was established in 1987 and works within the RFO to protect Okapi and their habitat, as well as the culture of the indigenous Mbuti pygmies. Project activities include capacity building, agroforestry and community support (Gilman International Conservation 2010). The Wildlife Conservation Society started field surveys and research on Okapi in RFO and elsewhere in DRC in the 1980s. Several other international NGOs have also conducted Okapi-related work in DRC, including Fauna & Flora International, Frankfurt Zoological Society, the Lukuru Foundation, and the Zoological Society of London (ZSL). The first-ever species-wide Okapi conservation strategy was developed at a workshop held in DRC in May 2013 that was organised by ZSL in partnership with ICCN (Kümpel et al. 2015). In March 2013 a new IUCN SSC Giraffe and Okapi Specialist Group was established, co-hosted by ZSL, with the aim of coordinating research and conservation on both giraffid species and supporting implementation of the Okapi conservation strategy.
East, R. (compiler). 1999. African Antelope Database 1998. IUCN, Gland, Switzerland and Cambridge, UK.
Gilman International Conservation. 2010. Annual Report. Gilman Intenational Conservation. Available at http://www.theokapi.org.
Hart, J.A. 2013. Okapia johnstoni. In: J.S. Kingdon and M. Hoffmann (eds), The Mammals of Africa. Volume VI:Pigs, Hippopotamuses, Chevrotain, Giraffes, Deer and Bovids, pp. 110-115. Bloomsbury Publishing, London.
Hart, J., Beyers, R., Grossmann, F., Carbo, M., Dino, S. and Kahindo, F. 2008. La Réserve de Faune à Okapis. La distribution et fréquence de la grande faune et des activités humaines. Avec une évaluation de l'impact de 10 ans de conflit: 1996 - 2006. Wildlife Conservation Society. Inventory Monitoring Unit, Technical report no. 9, New York, USA.
Hicks, T.C. 2010. A chimpanzee mega-culture? Exploring behavioral continuity in Pan troglodytes schweinfurthii across northern DR Congo. PhD Thesis. University of Amsterdam, The Netherlands.
IUCN. 2015. The IUCN Red List of Threatened Species. Version 2015-4. Available at: www.iucnredlist.org. (Accessed: 19 November 2015).
Kingdon, J. 1979. East African Mammals. Volume IIIB. Academic Press, New York.
Kümpel, N.F., Quinn, A., Queslin, E., Grange, S., Mallon, D. and Mapilanga, J.J. 2015. Okapi (Okapia johnstoni) Conservation Strategy and Status Review. Zoological Society of London, IUCN and ICCN, London, UK, Gland, Switzerland, and Kinshasa, DRC.
Ngbolua, K., Mafoto, A., Molongo, M., Magbukudua, J.P., Ngemale, G.M., Masengo, C.A., Patrick, K., Yabuda, H., Zama, J. and Veke, F. 2014. Evidence of new geographic localization of Okapia johnstoni (Giraffidae) in Republic Democratic of the Congo: the rainforest of “Nord Ubangi” District. Journal of Advanced Botany and Zoology 2(1): 1-2.
Nixon, S. and Lusenge, T. 2008. Conservation Status of Okapi (Okapia johnstonii) in Virunga National Park, Democratic Republic of Congo. Zoological Society of London, London, UK.
Nixon, S.C. 2010. Participatory assessment of Grauer's eastern gorilla and other wildlife in the Lubutu sector of Maiko National Park and adjacent forests. Fauna & Flora International. Unpublished report, Cambridge, UK.
Petric, A. (ed.). 2012. Proceedings of the International Okapi Meeting, Jacksonville Zoo, 8-11 November 2012 . Jacksonville Zoo, Jacksonville, Texas.
Vosper, A., Masselink, J., Maisels, F. 2012. Great ape and human impact monitoring in Okapi Faunal Reserve, Democratic Republic of Congo. Unpublished report submitted to USFWS.
|Citation:||Mallon, D., Kümpel, N., Quinn, A., Shurter, S., Lukas, J., Hart, J.A., Mapilanga, J., Beyers, R. & Maisels, F. 2015. Okapia johnstoni. The IUCN Red List of Threatened Species 2015: e.T15188A51140517.Downloaded on 22 September 2017.|