Many aspects of habitat selection have been largely ignored in conservation planning of large mammals, including variation between day and night movement patterns, inter-individual niche variation of conspecifics and translocated individual‟s responses to new environments in relation to the influence of ecogeographical variables. Being a solitary moving animal with a known tendency to move through the night, the black rhino Diceros bicornis is a perfect species to test theories about individual spatial and temporal variation in habitat utilisation. I tested the appropriateness of using carrying capacity (CC) estimates as a tool for population conservation planning, and as an indicator of habitat utilisation for black rhino. I found individual selection was not related to the value of the habitat according to modelled CC. I therefore do not recommend the use of a priori calculations of resource quality and abundance of habitats (CC estimates), which do not take into account the factors that influence an animal‟s selection of a habitat, as indicators of species habitat use. Secondly I tested whether current methods of analyzing mainly diurnal location data of animals result in accurate ecological or conservation conclusions. I found a circadian variation in habitat use for different behaviours, and that excluding nocturnal data from home and browsing range analyses would provide inaccurate results for black rhino habitat use. I then tested for inter-individual niche variation amongst two populations of black rhino at various scales of selection, ranging from habitat through to browse selection. I showed that black rhino, a selective browser, had a significant degree of inter-individual habitat and dietary niche variation. Consequently, pooling habitat location data and diet selection data for black rhino individuals in a population does not reflect the actual selection of any, or many, individuals. To clarify which ecogeographical variables might influence this selection I ran maximum entropy models on individual‟s diurnal locations across the landscape. I was then able to develop a habitat suitability model which was based on the individual rather than population, providing a more accurate prediction. I repeated the individual models in phases, from the initial post-release phase after the release of individuals onto a new reserve through to their „settled‟ phase, allowing me to explore the effect of habitat variables on different settling phases of translocated animals. The results indicate that all the rhinos‟ acclimation phase lasted no longer than 25 days and that to minimize disturbance to the settling process all individuals in a newly released cohort should be released within this period. This study as a whole provides conservation managers with a better ecological understanding of black rhino in conjunction with a number of management tools. This will enable conservation managers to better understand the way animals utilise and perceive their environment, allowing for better monitoring and analyses of animal movements. This will aid in the development of strategic management plans in the conservation of not only animal species but also the ecosystems that they reside in and the identification of suitable areas for future conservation of animal species. / Thesis (Ph.D.)-University of KwaZulu-Natal, Westville, 2010.

A large purse-seine fishery is located in the highly productive southern Benguela System off the western Cape. Purseseine fisheries have been prone to collapse worldwide and management practices have met with limited success. Predators offer potential as biological indicators yielding information on the status of fish stocks. The rationale behind this proposed usage was previously loosely-defined. The premise that some variable of seabird biology is related to some aspect of fish biology about which information is required was critically examined. The diet of the Cape Gannet was monitored monthly at Lambert's Bay and Malgas Island in the western Cape from 1977 to 1986. Gannets ate shoaling fishes (mainly Cape Anchovy, South African Pilchard and Saury) , measuring 29-429 mm Lc, which were available during the day at the surface and hake offal scavenged from demersal trawlers. Comparison with purse-seine fishery catches and the distributional ecology of the fishes suggested that the contributions of epipelagic fishes to the diet of the Cape Gannet were related to their availability and abundance, but that the occurrence of mesopelagic fishes (adult Redeye Roundherring and Onderbaadjie) in the diet of gannets was not related to their availability or abundance. Availability of epipelagic fishes was apparently lowest during late winter and spring; at longer time scales, availability was apparently lowest between 1983 and 1985 during the period from 1978 to 1986. Differences in the diets of breeding and nonbreeding gannets were small. Gannets from the colony at Lambert's Bay fed primarily north of Cape Columbine. These birds fed in cool inshore waters on juvenile fishes (mainly Cape Anchovy). Gannets from Malgas Island fed primarily south of Cape Columbine. They fed in cool inshore waters on juvenile epipelagic fishes (mainly Cape Anchovy), in warmer waters offshore on large epipelagic fishes (Saury and adult pilchard) or scavenged hake at trawlers offshore. Adult South African Pilchard were preferred prey. Epipelagic prey were selected in preference to mesopelagic fishes and hake. Significant correlations between the percentage of pilchard in gannet diet and purse-seine fishery catches suggested that gannets were reliable monitors of the trend in pilchard stocks at low biomass levels. The Saury is a poorly known species and its availability to gannets was reviewed as an example of the indirect use of the diets of predators in understanding the ecology of prey species, and functioning of ecosystems. Future directions for research were suggested. However extensive use of data from predators in fisheries management awaits the development of techniques which can use qualitative data. Nevertheless, it was concluded that the species composition and length of prey in gannet diet and the mass of regurgitations and the proportion of birds which regurgitated food were related to the abundance of epipelagic fish prey generally and South African Pilchard in particular. / Thesis (Ph.D.)-University of Natal, Pietermaritzburg, 1987.

This study was undertaken to investigate the ecology of the Black-cheeked Lovebird Agapornis nigrigenis in the wild. Prior to this study little was known about the ecology of this parrot or other members of the genus Agapornis. The Black-cheeked Lovebird is classified as Vulnerable and has suffered a severe population decline and reduced distribution, from which, for largely speculative reasons, it has never recovered. The overall aim of this project was to elucidate the basic biology of the Black-cheeked Lovebird and determine the conservation actions which are necessary to conserve the species in the wild. Fieldwork was conducted across the species' range in south-west Zambia over twenty-two months between May to December 1998; March to December 1999; and February to May 2000. An education project focussing on Black-cheeked Lovebird conservation was conducted with local schools, villagers and Zambia Wildlife Authority scouts during September 2001. Historical records pertaining to distribution of the Black-checked Lovebird, both within and beyond Zambia are few, anecdotal and often discredited, and it is suggested that the species should be considered as endemic to Zambia. Within its core range the species has a clumped and localised distribution, associated with Mopane woodland and permanent water sources. Two sub-populations occur and appear to be distinct. Black-cheeked Lovebirds were most active, in the early morning and late afternoon, forming the largest daily flocks sizes during these times, which correlated with drinking and feeding activities. The smallest flock sizes occurred when roosting. Overall flock sizes were significantly larger during the dry (non-breeding) season. Black-cheeked Lovebirds were observed feeding on 39 species. Food items included seeds, leaves, flowers (especially nectar), fruit pulp, invertebrates, bark, lichen, resin, and soil. Various foraging techniques were used. Terrestrial foraging was dominant, with little temporal or spatial variability. Arboreal foraging in plants varied seasonally and by availability. Feeding preferences were not specialised and there was no dependence on a limited food resource. Black-cheeked Lovebirds fed on two agricultural crops. There was no evidence to suggest an extended foraging range during the crop-ripening season, or the reliance on crops for survival. The crop-ripening season coincided with the lovebird breeding season. The species is widely perceived as a crop pest, with 18% of seed heads of millet crops suffering more than 20% damage during the ripening season. Local farmers attempted to protect their crops in a variety of ways, however, these were largely ineffective and rarely lethal to lovebirds. The importance of elevating local tolerance for the species through education programmes is highlighted. This study presents the first collection of breeding data on the species. Breeding occurred from midlate January to early May. A single clutch was raised by most pairs per breeding cycle. Seventy-eight nests were found and characteristics measured. Fidelity to nest-sites is suspected. Although breeding behaviour was non-cooperative most nests were found in a loosely clumped distribution. No nesting requirement appeared to be in limited supply, or had reason to affect the population's reproductive output. Behavioural data on nest location, building, defence and predation are presented. In addition courtship, copulation, parental care and juvenile behaviours are reported. Data on clutch size, laying intervals and hatching success with captive birds are included. One nestling tested positive for Psittacine Beak and Feather Disease Virus (PBFDV). Other observations suggest PBFDV is present in the wild population. Implications for research and conservation are discussed. Black-cheeked Lovebirds roosted inside naturally formed cavities in live Mopane trees. Roost cavities were found in a loosely clumped distribution. No roosting requirement appeared to be in limited supply. Black-cheeked Lovebirds are highly dependent on surface water supplies and need to drink at least twice daily. The lovebirds are highly cautious drinkers that will not drink if the water resource was actively disturbed by humans or livestock. Water availability is a limiting factor to the Black-cheeked Lovebird. The gradual desiccation of its habitat appears to be the major cause behind the reduction of occupancy within its small range. Over the last 45 years (1950 - 1997) the annual rainfall in the Black-cheeked Lovebird's habitat has decreased resulting in further reduction of its already highly localised distribution increasing the species dependence on artificial water supplies. The conservation management of the species should be prioritised towards maintaining and creating water resources with minimal external disturbance; upholding the wild-caught trade ban in the species, continuing environmental education with local schools promoting lovebird conservation, and monitoring populations through dry season water source counts. / Thesis (Ph.D.)-University of Natal, Pietermaritzburg, 2003.

This work investigated two important evolutionary processes - speciation and adaptive variation - in two chromosomally-distinct allopatric Natal Midlands populations of the vlei rat Otomys irroratus. The two populations, at Kamberg and Karkloof, differ in the presence of a tandem fusion between chromosomes seven and 12 in the Kamberg karyotype. Speciation studies considered possible reproductive isolating mechanisms. In studies of adaptive variation, socio-ecological characteristics of both populations were investigated. Data on breeding and postnatal development provided evidence of post-zygotic barriers. Interpopulation pairs had reduced breeding success compared to intrapopulation pairs, and some hybrids died before weaning. Surviving hybrids had reduced growth rates, and almost all were sterile. In tests of pre-mating reproductive isolation, ethological barriers were emphasized. Individuals preferred same-population mates, suggesting the existence of mate recognition, which was achieved by means of population-specific courtship behaviour and communication, particularly olfactory, tactile and visual cues. No evidence of population-specific acoustic signals was found, although acoustic cues were associated with agonistic interaction, complementing other communicatory cues to promote increased aggression during interpopulation pairings. Laboratory studies of behaviour and morphology and field work (trapping and habitat assessment) provided information about socio-ecological parameters. The Kamberg habitat was harsher than the Karkloof one, as revealed by differences in seasonal and spatial availability of food and·cover. Cover was the key determinant of the level of sociability of both populations. Sparse, patchy cover selected for a partially communal social system in Kamberg o. irroratus: females were intrasexually tolerant and males were intrasexually highly aggressive. This, in conjunction with male-biased sexual dimorphism, implied that mating was polygynous. Abundant, uniform cover selected for a dispersed social system in Karkloof o. irroratus: females were intrasexually less tolerant than males. Ritualized aggression between males and a low degree of male-biased sexual dimorphism suggested that male may have overlapping home ranges in nature and that mating is promiscuous. Females possibly mated with dominant males, however. Contrasting social systems suggest that adaptation to local environmental circumstances has occurred in allopatry, and that Kamberg and Karkloof o. irroratus are undergoing adaptive speciation. Post-zygotic and pre-mating reproductive barriers appear to have evolved independently in both populations, and could potentially impede gene flow between the populations should they become sympatric. The presence of the tandem fusion in the Kamberg karyotype which, together with genetically-determined factors, may have caused hybrid sterility, suggests that this population is a chromosomally-determined incipient sibling species. / Thesis (Ph.D.)-University of Natal, Durban, 1993.

This study was undertaken in the Karoo, a semi-arid grazing land in South Africa, to elucidate the interaction between grasshopper assemblages and various aspects of the Karoo landscape. It falls into four sections, the first of which was a three-year study which was undertaken on and around a prominent South African mesa to determine its role as an elevational conservation refugium for grasshoppers in a sea of grazed flatlands (Chapter 2). The number of grasshopper species and individuals on the summit, slopes and flatlands varied significantly, in relation to measured environmental variables. The summit, through inaccessibility to livestock grazing, was effectively a conservation refugium for one grasshopper species, Orthochtha dasycnemis. There was no significant difference in species richness between years of sampling, although there were significant variations in grasshopper abundance between years. The difference in rainfall between years was significant and appeared to be the key factor influencing grasshopper population dynamics. This clearly shows that a mesa can act as a conservation island and refugium supporting an insect assemblage that would be otherwise altered by heavy livestock grazing on the surrounding flatlands. This summit assemblage is strongly linked with that on the slopes and below, and is determined not so much by an island effect per se, but by low grazing intensity and associated soil and vegetation structure. The second part of the study focussed on the interaction between grasshopper assemblage response and three hill sizes at a regional scale (Chapter 3). Small hills contained a significantly higher grasshopper species richness and abundance than medium and large hills. There were significantly higher number of small-sized grasshopper species and individuals than medium and large-sized ones. Flatlands surrounding small hills had significantly higher grasshopper species richness and abundance than those surrounding medium and large hills. The slopes of the three hill sizes did not show significant difference in species richness and abundance. There was no significant variation between the summits of the three hill sizes in species richness but they varied in grasshopper abundance. The summits of small hills had significantly higher grasshopper abundance than the summits of medium and large hills. Detrended Correspondence Analysis showed two clear grouping of sampling site and grasshopper species. While the flatlands of small hills formed a separate assemblage of several grasshopper species, slopes and summits of all hills formed another clump of few grasshopper species. Canonical Correspondence Analysis revealed that flaltands surrounding small hills occurred along increasing gradients of shrub cover whereas those surrounding medium and large hills occurred along increasing gradients of grass cover, vegetation density and greenness of grasses. Slopes and summits of all hill sizes occurred along increasing gradients of rock cover, cragginess, grass height and soil temperature. Patterns of grasshopper dominance were markedly variable among sites. There were low dominance patterns on flatlands of small hills where most species were rare. The distributional patterns varied of higher taxonomic groups varied among the three hill sizes. Small hills contained species from four families and nine subfamilies, but medium and large hills had only members of Acrididae in five subfamilies. About 50% of the total grasshopper abundance were associated with small hills. The study revealed the patterns of grasshopper assemblages at regional scale, and showed that variability in hill sizes across the Karoo has marked role in grasshopper conservation, and that grasshoppers interact differentially with variable hill sizes across the Karoo. The third part of the study was undertaken at twelve grassland sites in the Mountain Zebra National Park (MZNP) and the surrounding farms to assess changes in grasshopper assemblages to grazing by indigenous mammals inside the park in comparison with grazing by domestic cattle outside (Chapter 4). The MZNP has been restored from cattle-grazed farmland to indigenous mammal parkland for 62 years. The number of grasshopper species and families inside the park was not significantly different from outside the park, but the number of individuals inside the park was significantly higher. Multivariate statistics did not reveal any strong site groupings based on simple inside/outside comparisons, but there were clear groupings of sites based on vegetation characteristics and other environmental variables. The park boundary, therefore, does not significantly determine grasshopper assemblages, although intensity of grazing does. The indigenous mammals inside the park had the same effect as the domestic cattle outside, and it was the level of defoliation and trampling that was important rather than type of mammal. Very intensive livestock grazing and trampling leads to bush encroachment and reduction in cover and/or disappearance of several grass species. In response to this pressure, grasshopper populations dropped, with localized extirpation of some species. Vegetation composition and structure showed a significant influence on grasshopper assemblages, particularly grass height and percentage cover. The MZNP is thus a localized area of elevated grasshopper abundance in comparison with the surrounding farm landscape, and presumably represents a situation prior to the current, intensive farming activities. Such elevated grasshopper The significantly lower population of grasshoppers on the surrounding farms, with local extirpation of some species also suggests that the MZNP could be viewed as a local centre to which species with higher capacity for mobility may seek refugia from anthropogenic pressures. Hence the MZNP serves as a reference showing the difference between restored through- natural-succession and anthropogenically-disturbed habitats, and compares desirable with undesirable ecosystem changes for herbivorous invertebrates such as grasshoppers. The fourth part of the study was on grasshopper assemblage response to seasonal grazing (including summer, winter, spring and autumn grazing), rotational grazing, continuous resting and continuous grazing at a long-term experimental site (Chapter 5). Rotationally grazed sites supported the highest number of grasshopper species and abundance, while continuously-grazed sites had the lowest. Cluster analysis revealed that spring-grazed and winter-grazed sites were the most similar, with continuously-rested sites being the next most similar to these. Rotationally-grazed sites showed the lowest similarity to the rest of the sites. DCA showed clear groupings of sites and grasshopper species, with most species associated with rotationally grazed sites. Continuously-grazed sites had a different grasshopper assemblage. CCA showed that the assemblages followed definite gradients of measured environmental variables. Rotationally-grazed sites occurred along gradients of increasing bare ground, while continuously-grazed and summer-grazed sites occurred along increasing gradients of shrub cover and soil temperature. Spring-grazed, autumn-grazed, winter-grazed and rotational1y-grazed sites were characterized by high vegetation density. Grasshopper dominance patterns were very different at different sites. Summer-grazed sites had the highest percent dominance (40%) by Picnodictyaflavipes, while winter-grazed sites showed higher percent dominance (32%) by Pseudogmothela sp. The significance of variable grazing management systems for maintaining floral and grasshopper diversity is discussed. It is recommended that rotational grazing in this arid system is most suited to maintaining plant and insect diversity. These four parts in this study all clearly showed that grasshoppers interact with the landscape in a way that their assemblage patterns are dictated by patch as well as by regional dynamics. Topography in particular contributes significantly to biodiversity patterns at the spatial scale of landscape. But these patterns are also strongly determined by differential grazing pressures from domestic livestock which in turn interact with the various topographical features. These findings enable recommendations to be made on optimal grazing regimes relative to the hilly features of the landscape. The results also show that restoration which incorporates low-pressure grazing regimes and which takes cognizance of topographical features can maintain grasshopper abundance and diversity in the long term. / Thesis (Ph.D.)-University of Natal, Pietermaritzburg, 2001.

Invasions of ecosystems by exotic species are increasing and they may often act as a significant driver of the homogenization of the Earth’s biota, resulting in global biodiversity loss. Moreover, the addition of exotic species may have dramatic effects on ecosystem structure and functioning which may result in the extirpation of indigenous species. In 2004, a large population of an unknown lymnaeid was found in the Amatikulu Hatchery, northern KwaZulu-Natal, South Africa, and was subsequently found in few garden fish ponds in Durban. In 2007, it was identified using molecular techniques as Radix rubiginosa (Michelin, 1831) – a species widespread in southeast Asia. An invasion by R. rubiginosa is however likely to go unnoticed because its shell morphology resembles some forms of the highly variable and widely distributed indigenous lymnaeid, Lymnaea natalensis Krauss, 1848. Accurate and “easy” species identifications would permit the ready assessment of introduction histories and distributions, but in the present case identification was difficult due to unclear and contradicting accounts of the indigenous L. natalensis in the literature. A redescription of L. natalensis with emphasis on conchological and anatomical characteristics was therefore presented. This will help to distinguish variation between R. rubiginosa and L. natalensis and also assist those carrying out rapid bioassessment (SASS) surveys in South African rivers in recognising R. rubiginosa should it spread. For this, shells of R. rubiginosa and L. natalensis from both the UKZN Pond and the Greyville Pond were selected into either size class 1 (shell length < 10 mm) or size class 2 (shell length ≥ 10 mm). Six shell characters, shell length (height), shell width, aperture length (height), aperture width, length of last body whorl and spire height for each specimen was measured and analysed using principal component analysis (PCA) and The invasive potential of the freshwater snail Radix rubiginosa recently introduced into South Africa discriminant functions analysis (DFA). The most useful discriminant conchological characters were shell length, length of the last body whorl and aperture width. Use of these shell characters provided simple yet effective criteria for the separation of R. rubiginosa and L. natalensis. For both size classes R. rubiginosa had larger, more broadly ovate shells with longer (higher) body whorls than either of the two populations of L. natalensis that exhibited smaller, elongated shells with shorter (lower) body whorls. Also, R. rubiginosa had a narrower aperture width compared to the larger, wider aperture of the UKZN Pond L. natalensis population. The Greyville L. natalensis population was found to have narrower apertures than both R. rubiginosa and L. natalensis (UKZN Pond). The morphology of the radula and the reproductive anatomy of R. rubiginosa and L. natalensis from both the UKZN and Greyville Ponds showed little variation. The species did however vary in the relative numbers of radula teeth in each field and this serves as an additional useful diagnostic character. Both L. natalensis populations had similar mantle pigmentation patterns but that of R. rubiginosa was different. The mantle surface of R. rubiginosa was mottled black with patches of pale white to yellow. There were also large unpigmented fields and stripes that were not observed in L. natalensis. Having found characters to conveniently separate the alien R. rubiginosa from the indigenous L. natalensis, it became increasingly important to assess the potential invasiveness of this introduced species and its likely impact. The potential invasiveness of R. rubiginosa was assessed in relation to the already invasive North American Physidae Physa acuta Draparnaud, 1805 and the indigenous L. natalensis. This was particularly important in view of the success of P. acuta as an invader in South Africa. The hatching success, frequency of egg abnormalities, embryonic development, growth, survivorship, fecundity and life history parameters (GRR, Ro, rm, T and λ) for the four snail populations were assessed at three experimental temperatures (20oC, 25oC and 30oC). The invasive potential of the freshwater snail Radix rubiginosa recently introduced into South Africa The results showed that R. rubiginosa and P. acuta had a higher growth coefficient (K), longer survivorship, higher fecundity (higher hatching success, fewer egg abnormalities, longer duration of oviposition), shorter incubation period, greater life history parameters (GRR, Ro, rm and λ) and wider temperature tolerances than the two L. natalensis populations tested. The high adaptability of P. acuta to changing environmental factors such as temperature, is in agreement with the fact that it is now more widespread in South Africa than the indigenous species L. natalensis. This has important implications for R. rubiginosa, since this species displayed reproductive attributes and a temperature tolerance that were similar and in certain cases even exceeded the performance of the invasive P. acuta. This therefore implies that R. rubiginosa has the potential to colonize a wider geographical and altitudinal range than L. natalensis, and perhaps even P. acuta. Also, the superior reproductive ability of R. rubiginosa over L. natalensis is likely to present a situation that allows for its rapid spread as well as a possible impact on the indigenous L. natalensis that might render it vulnerable. / Thesis (Ph.D.)-University of KwaZulu-Natal, Westville, 2011.

The last thorough revision of the southern African holothurian fauna appeared in 1948 and since then there have been numerous additions to the fauna . A comprehensive revision of the fauna is here undertaken on the basis of currently accepted changes in classification and nomenclature. The survey is based on the collections of the South African Museum and of the Universities of Cape Town and Durban-Westville. The material comprises some 2768 specimens distributed over six orders and 72 species. Another 48 species, excluding the two pelagic forms, are included to complete the survey. The about 95 species recorded from this region prior to this investigation are tabulated in chronological sequence of their descriptions and/or records. The new taxa diagnosed include eight genera, one subgenus, 12 species and one subspecies. There are in addition 15 new records and 15 new synonyms. A checklist to all species known to date is included and keys reconstructed. Full descriptions of new species and those formerly inadequately described are given. The diagnoses of some others are modified and/or additional notes added. The zoogeographical distribution of the fauna, based on our current knowledge of ocean currents and their effects along the coast, is discussed and the following four faunal provinces recognised: tropical, subtropical, warm temperate and cold temperate. The relationship; of the Dactylochirotida and Dendrochirotida is discussed. The inclusion of the Rhopalodinidae in the Dactylochirotida is questioned and so is also the status of the cucumariid subfamily Colochirinae. It is concluded that the southern African holothurian fauna is of largely Indo-Pacific origin with most of the endemic component probably representing cold water tolerants of former Indo-Pacific species. The Atlantic Ocean region has played a very small but significant role in the development of the fauna, while the contribution of the Southern Ocean and Antarctic regions is negligible. / Thesis (Ph.D.)-University of Durban-Westville, 1984.

Chaerephon pumilus, the little free-tailed bat, (family: Molossidae) has a distribution throughout most of sub-Saharan Africa and the eastern region of Madagascar. The vast geographical distribution of this species is accompanied by considerable phenotypic variation, which may conceal cryptic species. The cytochrome b (845 nucleotides) and D-loop (314 nucleotides) regions of the mitochondrial DNA were sequenced to assess phylogenetic relationships within C. pumilus (southern Africa) and in relation to Chaerephon species from Madagascar (C. pumilus, C. leucogaster). Samples were obtained from KwaZulu-Natal, South Africa, and localities in Swaziland. The cytochrome b sample (n = 11) comprised four haplotypes, with a haplotype diversity of 0.6727, whilst the D-loop (n = 34) dataset comprised 13 haplotypes with a haplotype diversity of 0.8342. Neighbour joining, maximum parsimony and Bayesian analyses revealed congruent tree structures for both mtDNA regions. All Chaerephon taxa in this study formed a monophyletic clade with respect to the outgroup Mops midas. Chaerephon pumilus from the eastern side of Madagascar formed a well-supported monophyletic group, sister to a clade comprising C. pumilus (southern Africa) and C. leucogaster, and is suggested to comprise a separate species. Southern African C. pumilus formed two paraphyletic clades, A and B, separated by a genetic distance of 0.9 %. Chaerephon leucogaster formed a monophyletic group nested within southern African C. pumilus, suggesting conspecificity. However, the well-characterized morphology of C. leucogaster lends support to its specific status, and suggests the possible existence of cryptic species among southern African C. pumilus. Population genetic analysis suggests that two C. pumilus (southern African) clades have been expanding, one for between 2432 and 4639 years, and the other for the 11156 to 21280 years. A combined cytochrome b analysis, trimmed to 343 nucleotides, was carried out on the data from this study and that of Jacobs et al. (2004), also on southern African C. pumilus. Haplotypes from the Jacobs et al. (2004) study, which also identified two 0.9 % divergent clades (light- and dark-winged) were found to be identical or very similar to haplotypes from this study and were interspersed among southern African C. pumilus haplotypes in phylogenetic analyses. Chaerephon pumilus haplotypes from Zambia and Tanzania were found to be more closely related to those from southern Africa and to C. leucogaster than to C. pumilus (Madagascar), further indicating that this may be a separate species. Haplotypes from the light-winged clade of Jacobs et al. (2004) were identical to those of dark-winged samples from this study, suggesting that wing shade may not be diagnostic of the two clades. / Thesis (M.Sc.)-University of KwaZulu-Natal, Westville, 2008.

Perceived predation risk has a large impact on how prey species utilise landscapes. In an effort to reduce predation risk, individuals tend to utilise safer areas more than unsafe areas. How perceived predation risk affects the utilisation of landscapes by animals is termed a “landscape of fear”. Vervet monkeys (Chlorocebus pygerythrus) have a landscape of fear that operates in both horizontal and vertical planes. Within this landscape, vervets perceive the safest area to be up in a tree, under the canopy. To reduce predation risk, vervets use various predator-specific alarm calls and have been found to eavesdrop on the alarm calls of other species (e.g. birds). In this study, I explored whether vervet monkeys were able to associate eavesdropped alarm calls with specific predator types (i.e. aerial and terrestrial) as they do with their own predator specific alarm calls. To do this, I first quantified the three-dimensional landscape of fear for vervet monkeys by measuring giving up densities in artificial patches. I then used playbacks of the vervets’ aerial and terrestrial predator alarm calls, the alarm call of a red-backed shrike, and a mixed-species flock mobbing call to manipulate perceived predation risk. By comparing changes in foraging intensity within the patches, I quantified the specific reactions of the vervet monkeys to aerial and terrestrial predators. In addition, I found that the monkeys did not eavesdrop on the red-backed shrike call. However, the vervets did eavesdrop on bird mobbing calls, and associated the calls with the location of the potential treat and reacted as if it was a particular predator type. Specifically, the vervets reacted to mobbing calls played from up in a tree the same way as they did if an aerial predator was present, and calls from the ground as if a terrestrial predator was present. Thus, this suggests that they were able to associate a non-functional referential call (i.e. the mobbing call) with specific information, gathered from the location of the calls, and interpreted it in a referential manner. Moreover, intensity of these reactions (as measured by total feeding effort) indicated that vervets saw aerial predators as a greater threat compared to terrestrial predators. Ultimately, my results suggest that vervets can associate eavesdropped calls with specific predators, and this likely provides a fitness benefit in a dangerous and unpredictable world. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2013.

Predation and abiotic processes rather than competition should influence the community structure of rodents and shrews with life histories characterised by high fecundity, short longevity and unstable populations. I investigated the influence of abiotic processes, predation and competition on three parameters of community structure (species composition, phenotypic and phylogenetic niches) of rodents and shrews at Mkhuze and Kube Yini, two game reserves in KwaZulu-Natal, South Africa, using null models and multivariate analyses. Rodents and shrews were sampled between 2007 and 2009. Sample-based rarefaction curves indicated that rodent species richness was higher at Mkhuze than at Kube Yini, while shrew species richness was identical at both reserves. Species richness estimators indicated that estimates of species richness were fairly accurate, hence strengthening the results from my null model analyses. I found evidence that immigration and extinction operating at a regional scale influenced rodent species composition. Moreover, habitat filtering operating at a local scale influenced rodent and shrew species composition. These processes produced nested assemblages: species present at species-poor sites were subsets of species present at species-rich sites. Habitat filtering also influenced the phenotypic niche of rodents and shrews: sympatric species showed similar phenotypic adaptations (phenotypic niches were underdispersed), probably in response to similar food requirements. Furthermore, shrew phenotypic traits showed a convergent evolution, and local assemblages comprised distantly related species (phylogenetic evenness), suggesting the influence of habitat filtering on the phylogenetic niche structure of shrews. Predation influenced shrew phenotypes. Bullae and ears were underdispersed and larger than expected by chance, probably to reduce predation risk through increased hearing sensitivity. In contrast, I found no evidence that predation influenced the rodent phenotypic niche. Competition influenced the phenotypic niches of rodents and shrews in species-rich assemblages (phenotypic niches were overdispersed). In these assemblages, the coexistence of species was facilitated by dietary and microhabitat partitioning. Competition also influenced the phylogenetic niche of rodents: phenotypic traits showed a convergent evolution, and local assemblages comprised closely related species (phylogenetic clustering). In conclusion, both abiotic and biotic processes influenced different parameters of the community structure of rodents and shrews. However, despite similar life-history traits, the community structure of local assemblages differed between rodents and shrews. Comparing patterns and processes of community structure across taxa would help find general trends of community organisation. / Thesis (Ph.D.)-University of KwaZulu-Natal, Westville, 2012.