PRIMATES

Full screen Primates Id code: amd065

Cercopithecidae
Cercopithecus diana

(Linnaeus, 1758)

(Eng) Diana monkey

(Fre) Cercopithèque diane

Taxonomic notes

Two subspecies are described: C. d. roloway to the east and C. d. diana to the west of the Sassandra River (Lee et al., 1988).

IUCN threat category

Hunting and habitat destruction are the primary threats throughout its relatively restricted range, so C. diana is one of the most Vulnerable African primates both as a species (VU: criteria A1c+2c), and as C. d. diana (VU: criteria A1a), while C. d. roloway is considered Endangered (EN: criteria a1c).

Available information

Information available on the ecology of the Diana monkey is summarised in Lee et al. (1988) and Oates (1996). The ecology of this species is not known in detail. Habitat requirements are discussed by several authors (Booth, 1979; Fimbel, 1994; Galat & Galat-Luong, 1985). Booth (1979) and Galat & Galat-Luong (1985) also give some information on its activity patterns. Some behavioural aspects, including territoriality, are analysed in Galat & Galat-Luong (1985). Not much is known on its feeding habits (Booth, 1979). Notes on its ecology are also found in Bourliere (1985). Distribution and ecology are discussed in Lernould (1988) and Oates (1988). Notes on its presence in Ghana are found in Booth (1979). Due to habitat loss and severe hunting pressure, the species is included in the list of the most threatened African primates species. General information on the species’ ecology and distribution is found in Gautier-Hion et al. (1988), Kingdon (1997), and Stuart & Stuart (1997). Current status, population numbers and distribution are discussed in Lee et al. (1988), Oates (1994, 1996) and Southwick et al. (1986).

Known extent of occurrence

Fig. 2.3.8.a was obtained from Oates (1996). This species occurs in south Sierra Leone, Liberia, south Ivory Coast, west and south Ghana and in the Seredou area of southwest Guinea. Its northwestern boundary is probably the Afram River (Lee et al., 1988).

Categorical-discrete (CD) distribution model

This species lives primarily in mature rainforest; it also occurs in secondary and gallery forests (Kingdon, 1997; Lee et al., 1988; Booth, 1979).

Based on these environmental preferences, the following scores were assigned (Fig. 2.3.8.b) (Tab. 2.3.8.a):

Score
1	Primary forest.
2	Secondary and degraded forests and forest mosaics.
3(*)	Savannas and croplands.
(*) Scores increased for vegetation types occurring inside a 1-km buffer around permanent water

suitable		moderately suitable		unsuitable		Total
km²	%	km²	%	km²	%	km²	%
70 858	23	211 709	67	31 401	10	313 968	100

Tab 2.3.8.a: Cumulative size (km²) of areas pertaining to each environmental suitability class within the Extent of Occurrence.

	Number Patches (NP)	Mean Patch Size (MPS) km²	Patch Size SD (PSSD) km²	Largest Patch Index (LPI) %	Mean Shape Index (MSI)	Area-Weighted Mean Shape Index (AWMSI)
suitable	426	164	683	3.48	1.32	3.97
moderately suitable	68	3 115	24 669	72.81	1.53	21.05
Total AO	15	18 772	70 057	99.76	1.7	10.41

Tab 2.3.8.b: Area of Occupancy fragmentation indexes.

Probabilistic-continuous (PC) distribution model

The output of the probabilistic-continuous (PC) distribution model is shown in Fig. 2.3.8.c.

Validation

No occurrence of the species within the four sample areas.

Comments and conservation issues

The preference of this species for primary forests is the main reason for its threatened status. The EO is not large and only 23% appears to be of the best quality. These areas are then fragmented into a high number of very small patches (see the NP, MPS and PSSD) as confirmed also by the very small LPI (3.48%). A further 67% is classified as moderately suitable and probably contributes the most to the species’ distribution. However, these areas are also deeply interspersed with unsuitable areas (see the CD model) especially in Ivory Coast and Ghana where little natural forest is left. Moreover, only 2.2% of the total AO is included in existing protected areas, not enough to ensure the conservation of the species even if it were efficiently protected. As hunting and poaching persist, the species is classified as Vulnerable.

SUITABILITY CLASS	inside	outside	Total
suitable	1.06	21.51	22.57
moderately suitable	1.71	65.72	67.43
unsuitable	0.31	9.70	10
Total	3.07	96.93	100

Tab 2.3.8.c: Percent of environmental suitability classes within EO (as obtained from the categorical-discrete distribution model) inside and outside the protected areas.

References

Booth A.H. (1979). The distribution of primates in the Gold Coast. In: Sussman R.W. (Ed.). Primate Ecology. Problem-oriented field studies. Wiley, Chichester & New York: chap. 7: 139-154.

Bourlière F. (1985). Primate communities: their structure and role in tropical ecosystems. Int J. Primatol.: 6, 1-26.

Fimbel C. (1994). The relative use of abandoned farm clearings and old forest habitats by primates and a forest antelope at Tiwai, Sierra Leone, West Africa. Biological Conservation: 70, 277-286.

Galat G., Galat-Luong A. (1985). La communauté de Primates diurnes de la foret de Tai, Côte d'Ivoire. Revue de Ecologie (La Terre et la Vie): 40, 7-32.

Gautier-Hion A., Bourlière F., Gautier J., Kingdon J. (Eds) (1988). A Primate Radiation: Evolutionary Biology of the African Guenons. Cambridge University Press, New York.

Kingdon J. (1997). The Kingdon field guide to African Mammals. Academic Press, London and New York: Natural World.

Lee P.C., Thornback J., Bennet E.L. (1988). Threatened Primates of Africa. IUCN, Gland - Switzerland and Cambridge, UK.

Lernould J. (1988). Classification and geographical distribution of guenons: a review. In: Gautier-Hion A., Bourlière F., Gautier J., Kingdon J. (Eds). A Primate Radiation: Evolutionary Biology of the African Guenons. Cambridge University Press, New York: pp 54-78.

Oates J.F. (1988). The distribution of Cercopithecus monkeys in West African forests. In: Gautier-Hion A., Bourlière F., Gautier J., Kingdon J. (Eds). A Primate Radiation: Evolutionary Biology of the African Guenons. Cambridge University Press, New York: pp 79-103.

Oates J.F. (1994). Africa's primates in 1992: conservation issues and options. Amer. J. Primatol.: 34, 61-71.

Oates J.F. (1996). African Primates Status Survey and Conservation Action plan. IUCN/SSC Primate Specialist Group.

Southwick C.H., Mittermeier R.A., Robinson J.G., Tenaza R.A. (1986). Report of the American society of primatologists subcommitee on the status of primates in the wild. Amer. J. Primatol.: 10, 371-378.

Stuart C., Stuart T. (1997). Field guide to the larger mammals of Africa. Struik Publishers.