Frequent reports of damage caused by bushbuck and common duiker browsing on commercially important timber seedlings, and an interest in the potential and feasibility of hunting these two species on State land were the primary factors responsible for the Directorate of Forestry's motivation of this study. The study area at Weza State Forest comprised approximately 21 000 ha of plantations, grasslands and indigenous forests which were considered representative of timbered areas throughout the Natal midlands. Several methods of age determination were investigated and these findings permitted assessments of growth, fecundity and population structure. The physiological condition of both antelope species was examined in relation to age, sex, reproduction and management strategies, and the results discussed in conjunction with mortality patterns. Principal foods of both bushbuck and duiker were determined from rumen analyses while 112 marked animals were regularly monitored to facilitate assessments of habitat selection and levels of spatial and social organisation. of these largely solitary and Estimates of the abundance nocturnal antelope were influenced by local movements in response to the availability of food and cover which varied seasonally and also fluctuated dramatically with forest succession and timber management activities. Although bushbuck and duiker bred throughout the year and had almost identical rates of reproductive performance, different factors were responsible in limiting the sizes of these two populations. All the available evidence gathered in this study indicated that food resources during winter and early spring were inadequate for bushbuck, particularly in 1983 when 33% of the marked population died from starvation and/or exposure. Notable differences in forage utilization and habitat selection inferred little interspecific competition at this time of the year. In contrast, territorial duiker appeared to be susceptible to highly localised habitat modifications (including the availability of food and cover) which occurred throughout the year and resulted from silvicultural and timber harvesting practices. Rumen analyses and quantitative damage assessment surveys revealed that browsing on timber seedlings was usually confined to localised areas during the winter months and was much less severe than had been originally suggested. Conifers were regarded as a starvati~n food and methods of reducing damage to these young trees were recommended for potential problem areas. Both antelope species were considered overabundant at Weza and recommendations for the future management of these populations included the limited utilization of surplus animals, by sport hunting on a sustained yield basis, and methods of manipulating and improving forest habitats. / Thesis (Ph.D.)-University of Natal, Pietermaritzburg, 1986.

In Central Africa, wildlife populations are increasingly influenced by humans, even in protected areas. This raises the question how spatial patterns of wildlife abundance are affected by human activities and habitat and how these patterns change over time. I address these questions by developing spatial models combined with line transect survey data in two forest sites in Central Africa. In the Odzala National Park in the Republic of Congo, I examine elephant dung abundance data in relation to human threats and protection. In the Okapi Faunal Reserve in the Democratic Republic of Congo (DRC), I developed spatio-temporal models for elephants and other forest ungulates to examine temporal changes in their densities as a result of changes in human impact in the context of a civil war that took place in the region between the two surveys. Covariates related to human influences dominated the observed patterns at both sites. In Odzala, elephant dung densities were mainly influenced by protection. They were higher inside the protected area and closer to anti-poaching patrol routes. In the Okapi Faunal Reserve, populations of all ungulate species declined severely between the two survey periods. Declines in elephant abundance were relatively higher closer to the park boundary and areas of intense human activity. After the war, elephant densities were higher in a small area in the centre of the park that may have acted as a refuge. Forest duikers also declined, but the spatial pattern of their decline was different than that of elephants. Densities dropped more in the southern part of the reserve, probably due to pre-exisisting higher levels of hunting there. Besides explaining spatial patterns of abundance, spatial modeling was shown to be useful in improving the precision of density estimates and in predicting densities across a surface in the Odzala National Park. In summary, humans overwhelmingly determined the distribution and abundance of ungulates in both sites. The civil war in DRC led to a dramatic increase in elephant poaching for ivory which caused a major decline in elephant populations. It aggravated the bushmeat hunting of duikers whose populations also declined sharply.

In Central Africa, wildlife populations are increasingly influenced by humans, even in protected areas. This raises the question how spatial patterns of wildlife abundance are affected by human activities and habitat and how these patterns change over time. I address these questions by developing spatial models combined with line transect survey data in two forest sites in Central Africa. In the Odzala National Park in the Republic of Congo, I examine elephant dung abundance data in relation to human threats and protection. In the Okapi Faunal Reserve in the Democratic Republic of Congo (DRC), I developed spatio-temporal models for elephants and other forest ungulates to examine temporal changes in their densities as a result of changes in human impact in the context of a civil war that took place in the region between the two surveys. Covariates related to human influences dominated the observed patterns at both sites. In Odzala, elephant dung densities were mainly influenced by protection. They were higher inside the protected area and closer to anti-poaching patrol routes. In the Okapi Faunal Reserve, populations of all ungulate species declined severely between the two survey periods. Declines in elephant abundance were relatively higher closer to the park boundary and areas of intense human activity. After the war, elephant densities were higher in a small area in the centre of the park that may have acted as a refuge. Forest duikers also declined, but the spatial pattern of their decline was different than that of elephants. Densities dropped more in the southern part of the reserve, probably due to pre-exisisting higher levels of hunting there. Besides explaining spatial patterns of abundance, spatial modeling was shown to be useful in improving the precision of density estimates and in predicting densities across a surface in the Odzala National Park. In summary, humans overwhelmingly determined the distribution and abundance of ungulates in both sites. The civil war in DRC led to a dramatic increase in elephant poaching for ivory which caused a major decline in elephant populations. It aggravated the bushmeat hunting of duikers whose populations also declined sharply.

In Central Africa, wildlife populations are increasingly influenced by humans, even in protected areas. This raises the question how spatial patterns of wildlife abundance are affected by human activities and habitat and how these patterns change over time. I address these questions by developing spatial models combined with line transect survey data in two forest sites in Central Africa. In the Odzala National Park in the Republic of Congo, I examine elephant dung abundance data in relation to human threats and protection. In the Okapi Faunal Reserve in the Democratic Republic of Congo (DRC), I developed spatio-temporal models for elephants and other forest ungulates to examine temporal changes in their densities as a result of changes in human impact in the context of a civil war that took place in the region between the two surveys. Covariates related to human influences dominated the observed patterns at both sites. In Odzala, elephant dung densities were mainly influenced by protection. They were higher inside the protected area and closer to anti-poaching patrol routes. In the Okapi Faunal Reserve, populations of all ungulate species declined severely between the two survey periods. Declines in elephant abundance were relatively higher closer to the park boundary and areas of intense human activity. After the war, elephant densities were higher in a small area in the centre of the park that may have acted as a refuge. Forest duikers also declined, but the spatial pattern of their decline was different than that of elephants. Densities dropped more in the southern part of the reserve, probably due to pre-exisisting higher levels of hunting there. Besides explaining spatial patterns of abundance, spatial modeling was shown to be useful in improving the precision of density estimates and in predicting densities across a surface in the Odzala National Park. In summary, humans overwhelmingly determined the distribution and abundance of ungulates in both sites. The civil war in DRC led to a dramatic increase in elephant poaching for ivory which caused a major decline in elephant populations. It aggravated the bushmeat hunting of duikers whose populations also declined sharply. / Science, Faculty of / Zoology, Department of / Graduate

京都大学 / 0048 / 新制・課程博士 / 博士(地域研究) / 甲第20734号 / 地博第225号 / 新制||地||83(附属図書館) / 京都大学大学院アジア・アフリカ地域研究研究科アフリカ地域研究専攻 / (主査)教授 木村 大治, 准教授 安岡 宏和, 助教 佐藤 宏樹, 教授 市川 光雄 / 学位規則第4条第1項該当 / Doctor of Area Studies / Kyoto University / DGAM

The present study sets out to assess patterns of evolutionary diversification in central African duikers (subfamily Cephalophinae). The sampling strategy consisted of collecting geo-referenced duiker feces across 43 sites and seven countries. However, several challenges related to the use of non-invasive samples needed to be addressed prior to large scale DNA amplification. First, the best storage method for obtaining DNA from fecal samples needed to be established. Our study revealed that while silica is best for nuclear microsatellite analyses, RNAlater is the best storage medium for maximal mitochondrial amplification. Moreover, extracting DNA as early as possible always provided the best results. Second, since it is impossible to determine the species identity of duiker feces solely based on their morphology, a simple and reliable molecular method was needed. A tree-based approach based on ~650 base pairs of the control region amplified from reference samples was found to be the most reliable method to recover the identity of unknown samples. Third, for fine scale analyses of population genetic structure, a set of twelve nuclear microsatellites were assembled from existing bovid data. These microsatellites markers were chosen because they are very polymorphic, cross amplify among targeted taxa, co-amplify with combined markers of the same multiplex, and are powerful enough for individual identification. Patterns of mitochondrial and nuclear microsatellite variation were used to test two important hypotheses of diversification in the tropics: the Pleistocene refugia and the riverine barrier hypotheses. Analyses of historical and contemporary population genetic structure were carried out on the three most abundant species in our sampling area: the bay duiker (C. dorsalis), the Peter’s duiker (C. callipygus), and the blue duiker (P. monticola) using mitochondrial and nuclear markers described above. These data show that (1) southwest Nigeria and southwest Cameroon comprise genetically distinct populations in C. callipygus and P. monticola species, (2) signatures of demographic expansion for all three taxa are broadly coincident with the location of hypothesized upland refugia in Gabon and Equatorial Guinea and (3) the Sanaga, Ogooué, and Sangha rivers may constitute a partial riverine barrier and/or act as fluvial refugia for duikers.

The ecology of blue duikers Philantomba monticola and red duikers Cephalophus natalensis was studied in three lowland coastal evergreen forests in Natal. Variation in population densities, estimated with numerous census techniques and between and within study areas permitted comparisons of habitat parameters. Both species are strictly diurnal, and are active between 18 and 40% of the nycthemeral cycle. Usually a pair of blue duikers occupy a permanent territory of about 0,7ha while red duiker home ranges, between 2 and 15ha, overlap extensively with each other and those of blue duikers. Habitat quality of both species is determined by canopy cover (stem densities, spatial patterning, and, diversity of the tree and shrub layers), tree to shrub ratios, and, bedsites. The main dietary item, freshly fallen leaves, is not that of a highconcentrate feeder as hypothesised. Food appears to be abundant while condensed tannins have no influence on duiker densities. Management recommendations include land acquisition, forest ecology research, monitoring interaction with other species, genetic aspects, translocations and captive propagation. / Thesis (Ph.D.)-University of Natal, Pietermaritzburg, 1990.

The behavioural ecology of duikers (Cephalophus spp.) was studied in mature forest and mixed secondary vegetation around TaI National Park, Cöte d'Ivoire. The most common species in both vegetation types was C. maxwelli, followed by C. dorsalis, C. ogilbyi, C. niger, C. zebra and C. lentinki in mature forest, and C. niger, C. dorsalis and C. sylvicultor in secondary vegetation. Population surveys were carried out by a number of methods. Transect censuses by night were found most efficient in mature forest, whereas in secondary vegetation, only pellet transect censuses and drives into nets were possible. C. maxwelli populations were estimated at about 63 km2 in mature forest and 79 km2 in secondary vegetation. Duikers were primarily frugivorous, but the proportion of leaves taken increased in the season of fruit scarcity. Fruit abundance in different habitats increased with the age of the vegetation. Six C. maxwelli in mature forest and four in secondary vegetation were radio-collared to determine ranging patterns and social behaviour. They were diurnal and lived in groups of one male with one or two females and young. Home ranges, which were about 5 ha in size in mature forest and 3.6 ha in secondary vegetation, were defended by males, and the boundaries were marked by latrine areas by both sexes. In mixed secondary vegetation, all habitats were used except open fields and bamboo thickets. Implications for conservation and management are discussed. The continued preservation of mature forest and the control of poaching are essential for the survival of the three rarer species (C. -jentinki, C. zebra and C. ogilbyi). The control of poaching must precede any programme of sustainable harvesting of the more abundant species, which could be carried out in secondary vegetation. Duiker farming may be possible if low-cost sources of fencing and forage can be identified.

The blue duiker, Philantomba monticola and common or grey duiker, Sylvicapra grimmia represent two of the three duiker genera as well as two of the three species occurring in Southern Africa. The two species have not been adequately studied in their habitats within the Eastern Cape Province of South Africa, and this thesis centres around their biology with focus on diet and dental microwear. Faecal analysis was used to study the diet of blue duiker at Salem in the Albany district, and of common duiker on two farms, one a predominantly cattle farm at Kasouga and the other a farm for cultivation of chicory at Grants valley, both in the Bathurst district. The validity of faecal analysis was reviewed, and its applicability to blue and common duiker assessed. The method was appropriate for diet analysis of both species, as the common duiker is shy and secretive and the blue duiker is a rare and protected species which does not habituate readily. Results showed that the blue duiker was mainly folivorous with a seasonally stable diet of 79 percent dicot foliage and only 17 percent fruit. Common duiker diet at both study sites comprised mostly dicot foliage, with only two monocotyledonous plant species. Twenty-seven and nineteen plant species were identified in the diets of common duiker at Kasouga and Grants valley respectively and the annual percentage occurrences of dicot foliage in the diets were about 99 percent at both study sites. The predominantly browsing common duiker, therefore offered negligible competition for food resources to the grazing cattle on Kasouga farm. Both blue and common duiker fed selectively, with approximately one third of the total number of plant species identified in their diets providing at least 50 percent of the food eaten annually. Ehretia rigida was the most important plant species in the diets of both duiker species. Chicory, Chichorium intybus provided more than one third (35.6 percent) of the winter diet and a substantial proportion (14.4 percent) of the spring diet of common duiker at Grants valley, thereby confirming earlier reports of this species feeding on chicory and other cultivated crops. The diet of common duiker at Kasouga did not vary seasonally but that of common duiker at Grants valley did vary and this was attributed to utilisation of chicory. Results from the dental microwear analyses did not show any significant differences in dental microwear between blue and common duiker, but supported and confirmed that the two were browsing species, characterised by many pits and few scratches on their dental surfaces. A high incidence of pits was found on the dental surfaces of both duiker species, and was attributed to utilisation of fruit in the diet.

The 28-month study assessed the impacts of five syntopic medium-sized mammalian browsers and one fire event in a woodland savanna in the Matobo Hills, Zimbabwe. Aspects of herbivory, mechanical pressures, seed dispersal and nutrient cycling were investigated for three species of small antelope (common duiker [Sylvicapra grimmia]1, klipspringer [Oreotragus oreotragus] and steenbok [Raphicerus campestris]) and two medium-sized species (bushbuck [Tragelaphus scriptus] and greater kudu [T. strepsiceros]). Focusing on Burkea africana2 woodland, in a system that does not include elephant (Loxodonta africana), effects of browsing antelope on woody and herbaceous vegetation development were investigated using exclusion plots. Browsers regulated woody plant cover (measured as basal stem area), with smaller antelope having a greater impact than larger species. This was linked to feeding height, feeding selectivity and mechanical pressures (e.g. twig breakage and trampling). Fire caused an initial reduction in above-ground standing biomass, but in the presence of fauna, pre-fire equilibria were attained within 15 months. In antelope exclosures, herbaceous biomass increased and woody biomass decreased following fire. Responses by woody vegetation to browsing varied among species, with highly palatable species typically exhibiting compensatory regrowth. Woody species richness and abundance (especially of palatable species) increased in the absence of browsers, but species richness of the herbaceous layer was promoted by moderate disturbance (trampling or fire). Faecal deposition behaviour, primarily the use of latrines by small antelope, resulted in localised soil enrichment within defended territories. Decomposition rates (and therefore return of nutrients to the soil) varied among species and seasons, due to defecation site selection, accessibility to decomposers and desiccation rates of faecal pellets. Controlled seed germination experiments indicated that ingestion by small antelope enhances germination rates of large, hard-seeded fruits such as Sclerocarya birrea. However, germination of savanna seeds may require multiple cues. This study demonstrated the critical roles of small antelope in ecosystem functioning, and highlights the importance of the less visible impacts of frequently overlooked smaller mammalian herbivores. Perturbations to the faunal community, especially small antelope, are predicted to have substantial impacts on woody plant cover.