|Scientific Name:||Cephalophus ogilbyi|
|Species Authority:||(Waterhouse, 1838)|
|Infra-specific Taxa Assessed:|
Antilope ogilbyi Waterhouse, 1838
|Taxonomic Notes:||This species probably represents a species complex of three allopatric species. Indeed, one recognized subspecies, Brooke's Duiker (C. o. brookei), from West Africa, is now often regarded as a distinct species (Grubb and Groves 2001, Grubb 2005). Treated provisionally as a single species here, following Wilson 2001 and Kingdon 2013).
Intergrades and possible hybrids with Peter's Duiker C. callipygus have been reported and further investigation is desirable.
|Red List Category & Criteria:||Least Concern ver 3.1|
|Assessor(s):||IUCN SSC Antelope Specialist Group|
|Reviewer(s):||Hoffmann, M. & Mallon, D.|
All three subspecies are estimated to be declining (further details in the subspecies accounts). However, overall is listed Least Concern because it is unlikely that the decline for the species as a whole has yet reached a rate that would qualify for listing as Near Threatened. However, habitat degradation and destruction and over-hunting are ongoing threats and if current trends continue, the status of Brooke’s Duiker and the nominate subspecies will decline further until both become confined to a few effectively protected areas such as Taï and Sapo.
|Previously published Red List assessments:|
|Range Description:||Ogilby’s Duiker has a disjunct distribution in four areas of the equatorial forest zone in West and Central Africa (East 1999; Wilson 2001, Kingdon 2013): Brooke's Duiker C. o. brookei is endemic to the Upper Guinea Forest of West Africa, from Sierra Leone to south-east Côte d’Ivoire, and south-west Ghana; the nominate subspecies occurs on Bioko Island (Equatorial Guinea) and in south-east Nigeria and south-west Cameroon; the White-legged Duiker C. o. crusalbum occurs in Gabon, mostly south of the Ogooué River, and extreme north-west Republic of Congo.|
Native:Cameroon; Congo; Côte d'Ivoire; Equatorial Guinea (Bioko); Gabon; Ghana; Liberia; Nigeria; Sierra Leone
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||East (1999) produced an estimated total population of 35,000, including an estimated 5,000 Brooke’s Duikers, 12,000 C. o. ogilbyi and 18,000 of the white-legged form, though the latter estimate may be too low. Populations are probably decreasing throughout the ranges of Brooke’s Duiker and the nominate subspecies, with a few possible exceptions such as some protected areas. White-legged Duiker numbers are probably stable in considerable parts of its range in Gabon and north-western Congo where human population densities are very low.|
|Current Population Trend:||Decreasing|
|Habitat and Ecology:||Its preferred habitat is primary moist lowland forest, yet it is common in forest patches within the forest-savanna mosaic. It has been recorded in areas with a mix of high forest and logged forest, or high forest and secondary forest (but seems to be very rare in highly modified secondary forest). On Bioko, the species is also present in montane forest (to elevations exceeding 2,000 m) and in the higher altitude Schefflera forest zone, habitats which are normally occupied by other duiker species on the mainland (East 1999).|
|Generation Length (years):||4.6|
|Use and Trade:||This species is hunted throughout its range, but with particular intensity on Bioko, where the bushmeat trade has been well studied over a period of years (Colell et al. 1994; Fa et al. 1995, 2000; Juste et al. 1995; Butynski et al. 2001). Across the studies Ogilby's Duiker represent around 6% of wild animal carcasses at Malabo market. Colell et al. (1994) found that of animals taken by hunters in south-east Bioko, Ogilby's Duiker was the fourth most frequently collected species; 71% of these were shot and 29% were trapped. Less than 10% were consumed locally, the rest being taken to market, where prices as high as US$14 per carcass were paid in 1986 (Butynski et al. 2001), rising to US$94 in 2006 (W. Morra and G. Hearn pers. comm. in Kingdon 2013).|
|Major Threat(s):||Threatened by habitat destruction (due to agriculture, human settlement, and logging) and intense hunting pressure, mainly for bushmeat. Although hunting takes place throughout the range, it is particularly severe on Bioko (Kingdon 2013).|
Brooke's Duiker is now known to exist in reasonable numbers in only a few areas, such as Sapo National Park and some other forests in eastern Liberia and Taï National Park in south-western Côte d'Ivoire. It has disappeared from the Bomfobiri and Owabi wildlife sanctuaries where it formerly occurredm but was seen in Kakum NP by Wilson (2001).
The mainland population of the nominate subspecies has only a few remaining strongholds, e.g., Korup National Park (Cameroon) and Cross River N.P. (Nigeria); it has also been recorded from several forest reserves (Forboseh et al. 2007). It remains relatively numerous on Bioko Island (Equatorial Guinea). The effective protection of the Gran Caldera de Luba Scientific Reserve is crucial to the survival of this species on Bioko Island.
The distinctive White-legged Duiker is now known to be relatively widespread and numerous in Gabon, including protected areas such as Lope and the Gamba complex, and Odzala N. P. (Congo).
Listed on CITES Appendix II.
Butynski, T. M., Schaaf, C. D. and Hearn, G. W. 2001. Status and conservation of Duikers and other ungulates on Bioko Island (Fernando Poo), Equatorial Guinea. In: V. J. Wilson (ed.), Duikers of Africa: Masters of the African Forest Floor. A Study of Duikers, People, Hunting and Bushmeat, pp. 357-364. Chipangali Wildlife Trust, Zimbabwe.
Colell, M., Mate, C. and Fa, J. E. 1994. Hunting among Moka Bubis in Bioko: dynamics of faunal exploitation at the village level. Biodiversity and Conservation 3: 939-950.
East, R. (compiler). 1999. African Antelope Database 1998. IUCN, Gland, Switzerland and Cambridge, UK.
Fa, J. E., Garcia Yuste, J. E. and Castelo, R. 2000. Bushmeat markets on Bioko Island as a measure of hunting pressure. Conservation Biology 14: 1602-1613.
Fa, J. E., Juste, J., Perez del Val, J. and Castroviejo, J. 1995. Impact of market hunting on mammal species in Equatorial Guinea. Conservation Biology 9: 1107-115.
Forboseh, P. F., Eno-Nku, M. and Sunderland, T. C. H. 2007. Priority setting for conservation in south-west Cameroon based on large mammal surveys. Oryx 41: 255-262.
Grubb, P. 2005. Artiodactyla. In: D.E. Wilson and D.M. Reeder (eds), Mammal Species of the World. A Taxonomic and Geographic Reference (3rd ed), pp. 637-722. Johns Hopkins University Press, Baltimore, USA.
Grubb, P. and Groves, C.P. 2001. Revision and Classification of the Cephalophinae. In: V.J. Wilson (ed.), Duikers of Africa: Masters of the African Floor, pp. 703-728. Chipangali Wildlife Trust, Bulawayo,Zimbabwe.
IUCN. 2016. The IUCN Red List of Threatened Species. Version 2016-1. Available at: www.iucnredlist.org. (Accessed: 30 June 2016).
Juste, J., Fa, J.E., Perez del Val, J. and Castroviejo, J. 1995. Market dynamics of bushmeat species in Equatorial Guinea. Journal of Applied Ecology 32: 454-467.
Kingdon, J. 2013. Cephalophus ogilbyi Ogilby's Duiker. In: J. Kingdon and M. Hoffmann (eds), The Mammals of Africa. Volume VI: Pigs, Hippopotamuses, Chevrotain, Giraffes, Deer, and Bovids, pp. 273-275. Bloomsbury Publishing, London.
Wilson, V.J. 2001. Duikers of Africa: Masters of the African Forest Floor. Directory Publishers, Bulawayo, Zimbabwe.
|Citation:||IUCN SSC Antelope Specialist Group. 2016. Cephalophus ogilbyi. The IUCN Red List of Threatened Species 2016: e.T4148A50183770.Downloaded on 23 May 2017.|
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