Artiodactyla Id code: amd017Tragulidae Hyemoschus aquaticus (Ogilby, 1841) (Eng) Water chevrotain (Fre) Chevrotain aquatique Taxonomic notes No significant taxonomic notes. IUCN threat category Lower Risk, near threatened (LR: nt). Available information No specific studies on the ecology of this species have been carried out. Some information on its habitat is found in Coe (1975), who investigated the species’ presence on Mount Nimba (Liberia). Notes on its occurrence in eastern former Zaire are reported in Rahm & Christiaensen (1966). General information on the ecology and distribution of the species is found in Kingdon (1971-77, 1997) and Stuart & Stuart (1997). Known extent of occurrence 
The water chevrotain has a disjunct distribution, from Sierra Leone to Ghana, and from Nigeria to former Zaire, marginally entering Uganda. A first rough distribution map was obtained from Kingdon (1971-77), subsequently revised by Dr. R. East (23 June ‘97) and updated on the basis of information found in Kingdon (1997) (Fig. 8.3.1.a). Categorical-discrete (CD) distribution model The species occurs in riverine valleys within lowland rainforest, but also in gallery forests and thick bush near water (Kingdon, 1997; Coe, 1975). Based on these environmental preferences, the following scores were assigned (Fig. 8.3.1.b) (Tab. 8.3.1.a):
Tab 8.3.1.a: Cumulative size (km2) of areas pertaining to each environmental suitability class within the Extent of Occurrence.
Tab 8.3.1.b: Area of Occupancy fragmentation indexes. Probabilistic-continuous (PC) distribution model The output of the probabilistic-continuous (PC) distribution model is shown in Fig. 8.3.1.c. Validation
Tab 8.3.1.c: Categorical-discrete (CD) distribution model validation parameters.
Comments and conservation issues The known EO of this species is separated into two sub-areas: the one in west Africa appears to be of lower suitability and more fragmented, while the suitable areas in the main range in central Africa are apparently largely connected by moderately suitable patches, thus forming a relatively continuous AO. Both the validation process (Index of Accordance = 64.52%) and the PC model support these conclusions. Both models indicate unsuitable regions at the eastern limit, and some available areas outside the known EO boundaries: these areas should be further investigated, as knowledge of the species’ distribution is quite scarce. Existing protected areas cover less than 6% of the AO of this species, which is classified as Lower Risk.
Tab 8.3.1.d: Percent of environmental suitability classes within EO (as obtained from the categorical-discrete distribution model) inside and outside the protected areas. References Coe M.J. (1975). Mammalian ecological studies on Mount Nimba, Liberia. Mammalia: 39, 523-581. Kingdon J. (1971-77). East African Mammals. VOL I: primates, hyraces, pangolins, protoungulates, sirenians. VOL IIA: Insectivores and bats. VOL IIB: hares and rodents. VOL IIIA: carnivores. VOL IIIB: large mammals. VOL IIIC: bovids. VOL IIID: bovids. Academic Press, London and New York. Kingdon J. (1997). The Kingdon field guide to African Mammals. Academic Press, London and New York: Natural World. Rahm U., Christiaensen A. (1966). Les mammiferès de l'Ile Idjwi (Lac Kivu, Congo). Les mammifères de la foret equatoriale de l'est du Congo. Ann. Mus. Roy. Afr. Cent.: n° 149. Stuart C., Stuart T. (1997). Field guide to the larger mammals of Africa. Struik Publishers.
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