An assessment of human carnivore conflict in the Kalahari region of Botswana
- Authors: Klein, Rebecca Ann
- Date: 2014
- Subjects: Carnivores -- Botswana , Carnivores -- Effect of human beings on -- Botswana , Human-animal relationships , Predatory animals -- Control -- Botswana , Wildlife depredation -- Botswana
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5876 , http://hdl.handle.net/10962/d1013132
- Description: Human wildlife conflict is a considerable conservation challenge that threatens many carnivore species worldwide and is a result of complex socio-economic and ecological processes. An understanding of the drivers of conflict is essential for any efforts to achieve coexistence. This study investigated the levels of conflict, livestock management and tolerance amongst the farming communities of the Southern and Western Kalahari in Botswana. A questionnaire survey was completed with 310 farmers throughout the region. The majority of respondents regarded coexisting with carnivores as a challenge, with losses due to depredation perceived as the greatest problem facing farmers. Conflict was widespread throughout the study area, with some spatial variations for certain species. Cattle management levels were low and while smallstock management was better, the use of improved levels of management could reduce current levels of conflict. Tolerance levels were generally low with few respondents seeing the benefits of coexistence with carnivore species. The results indicated that farm type, gender, education level, source of income, livestock numbers, location and land use all have an effect on perceived conflict and tolerance levels and strongly interact with each other. In general cattleposts were characterised by higher proportions of females, lower education levels, more benefits derived from wildlife and veld products and fewer livestock than fenced ranches. They also experienced more conflict, carried out more management and had better tolerance levels. It could be that closer connections to the land and deriving benefits from natural resources resulted in more tolerance and this is certainly worth further investigation. An improvement in the use of effective methods of livestock management, targeted environmental education programs to develop a greater awareness for the conservation value of carnivores and a diversification of livelihoods to include benefits from natural resources have the potential to reduce conflict and improve tolerance in the Kalahari region.
- Full Text:
- Date Issued: 2014
A standardised protocol for roadkill detection and the determinants of roadkill in the greater Mapungubwe Transfrontier Conservation Area, Limpopo Province, South Africa
- Authors: Collinson, Wendy Jane
- Date: 2013
- Subjects: Roadkill -- South Africa -- Mapungubwe Site , Traffic safety and wildlife -- South Africa -- Mapungubwe Site
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5606 , http://hdl.handle.net/10962/d1002056 , Roadkill -- South Africa -- Mapungubwe Site , Traffic safety and wildlife -- South Africa -- Mapungubwe Site
- Description: Despite evidence suggesting that road traffic is a major threat to biodiversity loss, very little is known about its actual impact on wildlife populations in South Africa. Globally, road density and traffic volumes are increasing, and although huge budgets are devoted to the construction and upgrading of roads, there is little or no allocation to mitigation measures for protecting fauna in most countries, particularly Africa. Further, no global standardised protocol exists for the rapid assessment of roadkill or the most economical and efficient approach for assessing roadkill rates. Using vehicle field trials, the reliability of detecting artificially deployed roadkill was assessed. Roadkill detection rates decreased significantly at speeds >50 km/h and were also significantly influenced by light conditions (i.e. detection success was greater when the sun was high) and the position of the roadkill on the road (i.e. smaller roadkill on verges were often missed). These results suggest that roadkill sampling was most effective between 1.5 hours after dawn and 1.5 hours before dusk and that driving at slower speeds (<50 km.h⁻ₑ) was required to detect roadkill. This protocol was implemented across three ecological seasons on a 100 km paved road and a 20 km unpaved road in the Greater Mapungubwe Transfrontier Conservation Area, Limpopo Province, South Africa. Driven daily over a 120-day period (three periods consisting each of 40 days), a total of 1,027 roadkill were recorded. These comprised 162 species from all terrestrial vertebrate groups with birds being the most commonly encountered roadkill (50% of all incidents). The high numbers of vertebrates identified as roadkill suggests that road traffic could have potentially unsustainable impacts on wildlife populations and hence the biodiversity of the area. Seventeen variables were identified as possible determinants of roadkill occurrence with season, rainfall, minimum and maximum temperature, habitat type, grass height, grass density, fence type and vehicle type significantly influencing roadkill numbers. Significantly more roadkill were detected on the paved road (9.91/100km) than on the unpaved road (1.8/100km) probably because of greater traffic volumes and the increased speed that vehicles travelled on the paved road. Warmer temperatures and increased rainfall in the preceding 24 hours also increased road mortality numbers as animals tended to become more active during these times. Interestingly, more roadkill was detected in open roadside habitats compared to dense roadside habitats on both the paved and unpaved roads and when grass on the roadside verge was of intermediate height. Open habitat possibly may provide a natural corridor for wildlife which ultimately end up on the road. Roadkill numbers increased when certain other physical barriers, such as cattle fences, were present, probably because these barriers were more penetrable than electric fencing. A series of mitigation measures are proposed to reduce the impacts of roads on wildlife in South Africa. These mitigation measures highlight the need to address the balance between the development of a country’s transport infrastructure and the conservation of its fauna. It is important that research on the impacts of roads becomes standardised to enable robust statistical comparisons which will provide a greater understanding of the potential threats to vertebrate biodiversity
- Full Text:
- Date Issued: 2013
The diet and ecological role of black-backed jackals, Canis Mesomelas, in two conservation areas in the Eastern Cape Province, South Africa
- Authors: Brassine, Mathilde Chloé
- Date: 2012
- Subjects: Black-backed jackal -- South Africa -- Eastern Cape , Jackals -- South Africa -- Eastern Cape , Jackals -- Food , Wildlife conservation
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5660 , http://hdl.handle.net/10962/d1005344 , Black-backed jackal -- South Africa -- Eastern Cape , Jackals -- South Africa -- Eastern Cape , Jackals -- Food , Wildlife conservation
- Description: Mammalian predators are keystone species and can have disproportionately large impacts, relative to their abundance, on the communities and ecosystems they inhabit. In addition, predator-prey interactions (including bottom-up and top-down effects) are the fundamental linkage among species in food webs. Thus, understanding the food requirements of predators is imperative. There have been no comprehensive studies on the diet of black-backed jackals (Canis mesomelas) across a full seasonal cycle in the Albany Thicket Biome of the Eastern Cape Province. This biome is rich in plant diversity, is highly nutritious for herbivores and supports a large number of mammalian species, yet it is poorly conserved. The aim of the present study was to establish the diet of black-backed jackals on two conservation areas where thicket vegetation dominates (Great Fish River Reserve and Kwandwe Private Game Reserve). The diet was assessed using scats collected monthly from June 2009 to May 2010 and a sample of 25 stomachs over the same period. At both sites and across all seasons, mammalian hair was encountered most often (93% of all scats) and a total of 23 mammal species were consumed. Of the mammals recorded in the scats, hair from several ungulate species was encountered most frequently and these were mostly hider species (offspring hidden in tall vegetation just after birth). On a seasonal basis, the proportion of mammalian hair was lowest in autumn. However, the contribution of fruits (Carissa haematocarpa, Diospyros lycioides and Grewia robusta) to the diet was significantly higher during this season. This suggests that black-backed jackals may employ diet switching in the Eastern Cape as a mechanism to capitalise on seasonally abundant food sources. Based on the stomach content analysis, invertebrates were consumed as frequently as mammalian prey throughout the year but mammalian prey was recorded in greater quantity (i.e. volume and mass). Thus, scat analysis may have overestimated mammalian prey and fruits and underestimated the importance of invertebrates, particularly highly digestible species (e.g. termites). In spite of these differences, scat analysis demonstrated similar general and seasonal trends as the stomach content analysis. Thus, scat analysis can provide an efficient and relatively accurate source of information on the diet of blackbacked jackals in the Eastern Cape. Both stomach content and scat collection methods depicted the black-backed jackal as a generalist and opportunistic predator, mainly relying on mammals and invertebrates. Although the results of my study suggest that black-backed jackal may be important predators of certain ungulate species, further study on their prey preferences, actual biomass ingested and the effects on the population viability of prey species is required in order to develop a robust management plan for the species in the protected areas of the Eastern Cape.
- Full Text:
- Date Issued: 2012
The dispersal of African wild dogs (Lycaon Pictus) from protected areas in the Northern KwaZulu‐Natal Province, South Africa.
- Authors: Whittington‐Jones, Brendan Mark
- Date: 2012
- Subjects: African wild dog , African wild dog -- Conservation -- South Africa -- KwazuluNatal , African wild dog -- Dispersal -- South Africa -- KwaZulu-Natal , African wild dog -- Effect of human beings on -- South Africa -- KwaZulu Natal
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5893 , http://hdl.handle.net/10962/d1013414
- Description: The number of African wild dogs Lycaon pictus in Northern KwaZulu‐Natal, South Africa has increased substantially over the last six years. This is largely due to a managed metapopulation approach of introductions onto protected areas and private game reserves since 1998. Because of the increasing wild dog population, the likelihood of rural communities surrounding protected areas encountering dispersing wild dogs in northern KwaZulu‐Natal has also increased. Resident wild dog populations currently occur in Hluhluwe‐iMfolozi Park (HiP), Mkhuze Game Reserve (MGR) of Isimangaliso Wetland Park and Thanda Private Game Reserve (TPGR) all of which are bordered by a matrix of natural habitats and human settlements. Thus, land outside these protected areas could be utilized to expand wild dog distribution and provide connectivity between existing resident populations of wild dogs within KwaZulu‐Natal. To investigate the viability of such an approach, Maximum Entropy Modelling (Maxent) was used to characterize habitat niche selection of dispersing wild dogs, and to identify potential dispersal linkages between current wild dog metapopulation reserves. The model was calibrated using 132 location points collected from 2006 until 2009. From 2008 to 2009 I also conducted a survey of 247 community members in tribal authorities bordering HiP and MGR, to understand factors influencing attitudes towards wild dogs. A habitat suitability model with seven predictor variables had an AUC of 0.96 (SD = 0.02) and indicated four variables which best predicted probability of presence for dispersing wild dogs: elevation, road density, land cover and human density. The results suggest that elevation and land cover may be of greater influence for dispersing wild dogs than human density or activity. Elevation was the single most effective variable indicating a higher probability of presence for dispersing wild dogs in lower lying locations; peaking at approximately 200 – 300m a.s.l. Wild dogs also showed a preference for Woodland and Bushland habitats which in KwaZulu‐Natal tend to be found on lower lying topography. A preference for areas of lower human density and a highest probability of presence at road densities of approximately 0.7km/km2 or less would suggest that while wild dogs may show a tendency to avoid areas of high human activity, they can coexist in close proximity to humans. Respondent’s attitudes, knowledge of wild dogs and livestock husbandry were interpreted by the development of a set of indices. Attitudes were positively related to formal education levels and wild dog‐specific education, but were not influenced by demographic factors such as gender, age and employment status. Eighty three percent of respondents believed efforts to protect wild dogs should continue. Respondents with higher numbers of livestock tended to have more positive attitudes towards wild dogs despite generally incurring higher losses to carnivore depredation than those with less livestock. This appears to be because the financial burden of livestock losses to those with fewer livestock is perceived to be a loss of a greater proportion of total financial wealth. The study highlighted the substantial scope for improvement in livestock management. Theft (34 percent), drought (30 percent) and disease (14 percent) were ranked as the greatest problems facing livestock owners while predators were ranked as the greatest problem by only 4 percent of respondents. My findings suggest that wild dogs are generally viewed positively or with ambivalence. Concerns over the potentially increasing threat to livestock, as natural prey numbers outside protected areas decline and wild dogs disperse from natal packs, are likely to be manageable. However, wild dog population expansion within KwaZulu‐Natal will continue to rely on managed core populations on perimeter‐fenced metapopulation reserves with tolerant communities and landowners contributing to the connectivity of isolated reserves. Generation of tolerance can be instilled through continued advocacy and education, supported by conflict mitigation initiatives and rapid response to conflict reports. The implementation of incentive schemes for adjoining private landowners to co‐manage wild dog populations will need to be addressed in conjunction with managed metapopulation practices and law enforcement, to promote range expansion, and reduce potentially lethal edge effects and wild dog‐human conflict.
- Full Text:
- Date Issued: 2012
The spatial ecology and activity patterns of leopards (Panthera pardus) in the Baviaanskloof and Greater Addo Elephant National Park (GAENP), Eastern Cape Province, South Africa
- Authors: McManus, Jeannine Stephanie
- Date: 2009
- Subjects: Leopard -- South Africa -- Eastern Cape , Leopard -- Monitoring -- South Africa -- Eastern Cape , Leopard -- Conservation -- South Africa -- Eastern Cape , Leopard -- Ecology -- South Africa -- Eastern Cape , Spatial ecology -- South Africa -- Eastern Cape , Wildlife monitoring -- South Africa -- Eastern Cape , Animal populations -- South Africa -- Eastern Cape , Wildlife conservation -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5823 , http://hdl.handle.net/10962/d1007601 , Leopard -- South Africa -- Eastern Cape , Leopard -- Monitoring -- South Africa -- Eastern Cape , Leopard -- Conservation -- South Africa -- Eastern Cape , Leopard -- Ecology -- South Africa -- Eastern Cape , Spatial ecology -- South Africa -- Eastern Cape , Wildlife monitoring -- South Africa -- Eastern Cape , Animal populations -- South Africa -- Eastern Cape , Wildlife conservation -- South Africa -- Eastern Cape
- Description: The conservation of leopards in the Eastern Cape Province requires a holistic approach that considers both predator-human interactions as well as the biology of the carnivore. Numerous studies have been conducted on leopards within protected areas; however more information regarding the species is needed outside these areas to facilitate effective management of predators. The spatial ecology of the leopard (Panthera pardus) were studied in the Baviaanskloof and GAENP in the Eastern Cape. The Baviaanskloof is an extensive area of mountainous terrain (approximately 2665km²) which has a mosaic of land uses, and leopards move from conservation areas to farmland where they come into contact and conflict with farmers. This study examined the spatial ecology of leopards living on farmlands adjacent to protected land. The space utilization and activity patterns of six leopards were analysed. These animals were caught and released on farmlands in the Baviaanskloof (n=4) or translocated (n=2) when not possible to release on site. The animals were caught by means of fall-door, walk-in traps and fitted with Vectronic GPS collars that facilitated the collection of high quality GPS fixes from each animal. Data was collected using VHF and UHF telemetry to download data. An understanding of spatial requirements in areas with different land use, and the extent of overlap of space use with other leopards allow, for the first time in the region, the calculation of possible maximum population size. Analysis of range size was carried out using two methods: minimum convex polygon, and Kernel Utilization Distribution. Finally, a key predictor of space use is prey availability. I assessed the prey base using a grid of camera traps. The studied leopards revealed large range utilization with minimal overlap. The activity patterns suggest there is no preference between diurnal and nocturnal activity patterns and the population density was estimated between 0.3 - 1.3 leopards per 100km². Large home range sizes and low population densities suggest that leopards require large areas of suitable habitat, and that conservation efforts need to be extended beyond protected areas to ensure the long-term viability of leopard populations in such areas.
- Full Text:
- Date Issued: 2009
The effect of elephants (Loxodonta africana, Blumenbach, 1797) on Xeric Succulent Thicket
- Authors: Knott, Edward Joseph
- Date: 2007
- Subjects: Addo Elephant National Park (South Africa) , African elephant , Elephants -- South Africa -- Eastern Cape , Elephants -- Nutrition -- South Africa -- Eastern Cape , Elephants -- Ecology -- South Africa -- Eastern Cape , Elephants -- Behavior -- South Africa -- Eastern Cape , Succulent plants -- South Africa -- Eastern Cape , Woody plants -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5674 , http://hdl.handle.net/10962/d1005359 , Addo Elephant National Park (South Africa) , African elephant , Elephants -- South Africa -- Eastern Cape , Elephants -- Nutrition -- South Africa -- Eastern Cape , Elephants -- Ecology -- South Africa -- Eastern Cape , Elephants -- Behavior -- South Africa -- Eastern Cape , Succulent plants -- South Africa -- Eastern Cape , Woody plants -- South Africa -- Eastern Cape
- Description: This study looks at the impact of elephant feeding on the Xeric Succulent Thicket component of Eastern Cape Subtropical Thicket (ECST) in Addo Elephant National Park (AENP). Observations of elephant feeding were carried out and vegetation transects were surveyed for impact of elephant feeding. The results indicated that the Nyati elephants spent the majority of their time grazing (nearly 90%), particularly the cow-young herds, and especially when the herd gathered in larger numbers. Browsing events were concentrated on Acacia karroo (81%) and there was no significant difference between the sexes in their preference for this species. Despite being subjected to most of the browsing, the majority of A. karroo trees were undamaged and the effect of elephants was generally light. It appears unlikely that, three years after re-introduction to Nyati, the elephants have had an effect on community structure of the vegetation. Surveys were conducted on stands of the alien invasive weed prickly pear Opuntia ficus-indica, and it was recorded that elephants in Nyati have had a dramatic effect on prickly pear, utilising all adult plants assessed and destroying 70% of them. This level of destruction in such a short period of time suggests that prickly pear is a highly favoured species. The results from the present study suggest that elephants can play a role in the control of prickly pear. Results are discussed in terms of elephants as both megaherbivores and keystone species, and as agents of intermediate disturbance.
- Full Text:
- Date Issued: 2007
Feeding ecology, space use and habitat selection of elephants in two enclosed game reserves in the Eastern Cape Province, South Africa
- Authors: Roux, Candice
- Date: 2006
- Subjects: Shamwari Game Reserve (South Africa) , Kwandwe Game Reserve (South Africa) , Elephants -- South Africa -- Eastern Cape , Elephants -- Ecology -- South Africa -- Eastern Cape , Elephants -- Feeding -- South Africa -- Eastern Cape , Elephants -- Nutrition -- South Africa -- Eastern Cape , Elephants -- Behavior -- South Africa -- Eastern Cape , Elephants -- Habitat -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5699 , http://hdl.handle.net/10962/d1005385 , Shamwari Game Reserve (South Africa) , Kwandwe Game Reserve (South Africa) , Elephants -- South Africa -- Eastern Cape , Elephants -- Ecology -- South Africa -- Eastern Cape , Elephants -- Feeding -- South Africa -- Eastern Cape , Elephants -- Nutrition -- South Africa -- Eastern Cape , Elephants -- Behavior -- South Africa -- Eastern Cape , Elephants -- Habitat -- South Africa -- Eastern Cape
- Description: The development of small (<300 km²), private game reserves has become a trend, not only in the Eastern Cape Province, but also elsewhere in South Africa as a result of a shift in land use practise from agriculture to ecotourism. The resultant re-introduction of elephants to many of these reserves has lead to management concerns because of the limited research on small reserves regarding their impact on the vegetation. In this study I assessed the space use, habitat selection, diet and impact of two elephant populations on the vegetation in the Eastern Cape Province between February 2004 and March 2005. Home range sizes were calculated using the kernel utilization distribution method. Home range sizes for elephants on Kwandwe were significantly larger during summer than winter (p<0.05). There was no significant difference between the home range sizes of the herds and males within a season and during summer the elephants utilized about 75 % of the reserve and only 54 % during winter. On Shamwari, the herd utilized about 92 % of the reserve during summer and 83 % during winter; while the males utilized 76 % of the reserve. Core areas for both elephant populations shrank from summer to winter and were concentrated around the permanent water sources on each reserve. Habitat selection was assessed using χ² tests and Bonferroni confidence intervals. On Kwandwe, there was a significant difference between observed and expected use of vegetation types (p<0.05) and karroid shrubland was strongly avoided by both herds during summer and winter. The preferred vegetation types of the males ranged from relatively open (short euphorbia thicket, bushclump karroid thicket and karroid shrubland) to completely open (old lands). On Shamwari, subtropical thicket, bontveld and montane grassland were avoided; while primary and secondary acacia thicket, riverine thicket and cultivated lands were preferred. The predominant vegetation type in the home ranges of herds on Kwandwe and Shamwari was subtropical thicket. The diet was assessed by direct observations over two seasons and dietary preferences were calculated. There was a significant difference in the frequency of occurrence of plants in the diet on the two reserves (p<0.05) and no significant effect of time of day or season (p>0.05). Seventeen woody plant species were utilized on Kwandwe and 23 species were utilized on Shamwari. Grass constituted a significantly greater percentage of the diet in summer than winter (p<0.05). Elephants on Kwandwe showed a selective preference for Ozoroa mucronata, Pappea capensis and Acacia karroo; while on Shamwari, A. karroo was selected. Transects were conducted in two different vegetation types on each reserve so as to assess the impact of elephant on the vegetation and damage scores were then calculated from these data. There was no significant effect of vegetation type or elephant density on mean damage scores in Kwandwe (p>0.05). Five hundred and seventy-eight plants were assessed in the subtropical thicket vegetation type and 225 plants were assessed in the savanna-type vegetation, with more than half the trees showing low levels of damage that could not only be attributed to elephants. Mean damage was highest for Portulacaria afra and Pappea capensis in subtropical thicket and for Rhus spp. in the savanna-type vegetation. On Shamwari, 408 plants were assessed in subtropical thicket and 215 in the savanna-type vegetation, with more than 70 % of trees showing low levels of damage. There was a significant effect of plant species and elephant density on the mean damage scores in subtropical thicket, with Aloe ferox showing more damage than the other plant species (p<0.01). In the savanna-type vegetation, A. karroo was the most severely damaged. Overall, damage was greater in the thicket vegetation type compared to the more open vegetation type on both reserves.
- Full Text:
- Date Issued: 2006
The feeding ecology and habitat use of lions reintroduced to small, enclosed reserves in the Eastern Cape Province, South Africa
- Authors: Rapson, Jackie Anne
- Date: 2005
- Subjects: Lion -- Food -- South Africa -- Eastern Cape , Lion -- Behavior -- South Africa -- Eastern Cape , Predation (Biology) , Lion -- Nutrition
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5938 , http://hdl.handle.net/10962/d1018268
- Description: Lions have recently been introduced to a number of small (<300km²), enclosed reserves in the Eastern Cape Province as a draw-card for tourists. However, there have been few studies of lion behaviour or predator prey interactions within small reserves. Thus the aim of this study is to contribute towards a better understanding of the effects of space on diet and habitat use of re-introduced lions. The research was conducted at two small private reserves, Shamwari and Kwandwe. Kills were mostly large (55%, >120kg), adult (41%) and male (39%) and the five most commonly killed species (kudu, black wildebeest, warthog, bushbuck and Blesbuck) comprised 67.9% of all kills and 67.8% of total biomass consumed. In an attempt to overcome the problem of gaps in the kill lists, a subset of data, which excluded kills more than five days apart, was analyzed and this gave similar results to analysis of the full kill lists. Mean daily intake rates varied annually between 2.26 and 5.23kg.FEQ⁻¹ for the full data set and 4.53 and 1 0.46kg.FEQ⁻¹ for the subset. The difference between estimated (calculated using daily intake rates of 5 and 7.12kg.FEQ⁻¹) and observed offtake for each ungulate species reflected the preference ratings for that species. Analysis of bone marrow indicated that: lions killed ungulates in moderate to good condition; condition of culled animals was lower than that of kills; distal bones could be used in analyses; and that that bones exposed to the environment for at least a week could be used to analyze condition of prey. Home ranges and activity centers ranged from 21.42km² to 73.27km² and 2.7lkm² to 17.47km² respectively, which was smaller than expected from previous studies. Although, lions at K wandwe and Shan1wari preferred different vegetation types, at both reserves they generally occupied areas that were structurally similar to what has previously been reported. Continuous monitoring and analyses of diet, including condition of the prey, and habitat use will provide reserve managers with some of the necessary information to enable them to effectively manage their lion populations and to predict and minimize potential problems.
- Full Text:
- Date Issued: 2005
The feeding ecology, habitat selection and hunting behaviour of re-introduced cheetah on Kwandwe Private Game Reserve, Eastern Cape Province
- Authors: Bissett, Charlene
- Date: 2005
- Subjects: Kwandwe Game Reserve (South Africa) , Cheetah -- Behavior -- South Africa -- Eastern Cape , Cheetah -- Nutrition -- South Africa -- Eastern Cape , Cheetah -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5698 , http://hdl.handle.net/10962/d1005384 , Kwandwe Game Reserve (South Africa) , Cheetah -- Behavior -- South Africa -- Eastern Cape , Cheetah -- Nutrition -- South Africa -- Eastern Cape , Cheetah -- South Africa -- Eastern Cape
- Description: The re-introduction of cheetah onto small reserves in the Eastern Cape Province has created the opportunity to study this species in an environment (Valley Bushveld) in which it has not previously been studied and which is quite different from the less wooded habitats in which previous studies have occurred. Thus the aim of this study is to add to the growing number of studies of cheetah in more wooded habitats and to contribute a better understanding of the level of specialization or adaptability in space use, habitat selection, diet and hunting behaviour that the cheetah possesses. The research was conducted on Kwandwe Private Game Reserve from February 2003 to August 2004. Direct observations, scat analysis and continuous observations were used to avoid bias towards large sized prey found when only using direct observations to study diet. The cheetah killed 15 species and four of the five most important prey species (kudu, springbok, grey duiker and bushbuck) were hunted according to their abundance on the reserve, while impala, the fifth most important prey species, was avoided (i.e. preference index less than one) by the cheetah. The cheetah’s main prey was medium sized ungulates, although the three male coalition killed larger prey than females and females with cubs. The daily food intake per cheetah per day was calculated to range from 5.3kg/cheetah/day for the coalition to 8kg/cheetah/day for a solitary female. Home range areas ranged from 11.1 km² for female cheetah with cubs in a den to 65.6 km² for single female cheetah and core areas ranged from 6 km² for the three male coalition to 26.5 km² for independent cubs. Habitat selection by cheetah on Kwandwe varied between the social groups depending on their susceptibility to predation by lions, their need for cover and need for water, and was similar to what has been previously reported. The home range of the coalition incorporated the most open vegetation type (karroid shrubland) with surrounding denser vegetation, while females occupied areas of denser vegetation. Activity patterns and hunting behaviour varied between different cheetah social groups with female cheetah being more active during day light hours compared to males which made 38% of their kills after dark. The average chase distances for the various cheetah groups varied considerably, and the chase distance for successful hunts was longer than for unsuccessful for all groups except single female cheetah. The percentage of kills’ kleptoparasitised on Kwandwe was very low compared to other studies possibly due to the low density of direct competitors, which in turn lead to longer mean kill retention times. These results suggest that cheetah are more adaptable than previously thought and this adaptability may have important implications for their conservation.
- Full Text:
- Date Issued: 2005
Feeding biology of common and blue duiker
- Authors: Kigozi, Frederick
- Date: 2001
- Subjects: Duikers -- Nutrition -- South Africa -- Eastern Cape , Sylvicapra grimmia -- Nutrition -- South Africa -- Eastern Cape , Herbivores -- Nutrition , Folivores -- Nutrition , Teeth -- Abrasion
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5625 , http://hdl.handle.net/10962/d1004725 , Duikers -- Nutrition -- South Africa -- Eastern Cape , Sylvicapra grimmia -- Nutrition -- South Africa -- Eastern Cape , Herbivores -- Nutrition , Folivores -- Nutrition , Teeth -- Abrasion
- Description: 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.
- Full Text:
- Date Issued: 2001
The effects of melatonin on the testis, epididymis and sperm physiology of the Wistar rat
- Authors: Gwayi, Noluzuko
- Date: 2001
- Subjects: Rats as laboratory animals , Rats -- physiology , Spermatozoa , Melatonin , Testis , Epididymis
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5681 , http://hdl.handle.net/10962/d1005366 , Rats as laboratory animals , Rats -- physiology , Spermatozoa , Melatonin , Testis , Epididymis
- Description: Melatonin is a product of the pineal gland and is postulated to play an antigonadotropic role in the reproductive system of mammals. The reproductive system of non-seasonally breeding mammals is believed to be not as responsive to melatonin treatment as that of seasonally breeding mammals. Recently, there has been increasing support from in vivo and in vitro studies, for the hypothesis that melatonin has negative effects on sperm physiology, especially on sperm motility. High and/or low seminal concentrations of melatonin have been associated with abnormalities in human sperm motility and concentration. In this study, I examined the effects of melatonin on the testis, epididymis and sperm physiology, using in vivo and in vitro experiments, in a non-seasonally breeding mammal. Treatment, in vivo, with exogenous melatonin for six weeks did not inhibit testosterone production or spermatogenesis, nor did it affect the mass of the testes and epididymides at dissection, the concentration the morphology of speimatozoa. However, melatonin in vivo had a small, but significant negative effect on sperm motility and sperm motility index. In vitro incubation of spermatozoa Fith melatonin reduced the percentage (%) of forward progressive movement (fpm), increased the % reduction in fpm, reduced the vigor or quality of sperm motility, reduced the sperm motility index, and delayed and/or prolonged the transition of one pattern of sperm motility to the subsequent patterns. Melatonin increased the pH of the culture medium, and the increased pH, and the ethanol utilized as a solvent for melatonin, both negatively affected all the sperm motility parameters that were assessed in my study. The effects of ethanol increased with time, and the effects of pH increased with both time and increasing pH. Melatonin in vitro did not inhibit capacitation and the acrosome reaction, but it delayed the onset and the progression of capacitation and the acrosome reaction. These results suggest that while melatonin did not inhibit spermatogenesis in the Wistar rat, it may influence sperm motility. Therefore, the presence of high concentrations of melatonin in the reproductive fluids may inhibit sperm motility. With further detailed research, melatonin may have a potential use as a contraceptive drug.
- Full Text:
- Date Issued: 2001
Aspects of reproduction in the four-striped field mouse, Rhabdomys pumilio
- Authors: Jackson, Claire
- Date: 2000
- Subjects: Microtus , Mice , Mice -- Reproduction
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5637 , http://hdl.handle.net/10962/d1005319 , Microtus , Mice , Mice -- Reproduction
- Description: Rhabdomys pumilio, in the Eastern Cape of South Africa, does not use short day length as an inhibitory cue for reproductive activity, and, despite previous records indicating that these mice are strictly seasonal in their reproduction, litters have been found during the winters of some years,both in the Eastern Cape and in the Western Cape. This led me to believe that the reproductive activity of Rhabdomys pumilio is more opportunistic and that the cue or cues used to control reproduction are less predictable and, or more variable than the photoperiod cue used by many seasonally reproducing rodents. Two experiments were conducted, investigating the influence of low ambient temperature (15⁰C)and reduced food availability on the reproductive activity of both male and female four striped field mice. Mice were maintained in one of four conditions (food restricted at 15⁰C, food restricted at 26⁰C, ad lib. food at 15⁰C, and ad lib. food at 26⁰C) for 4 (males) and 8 weeks (females)(photoperiod 12L:12D, humidity 40%). Results indicated that the males reduced their reproductive activity slightly when exposed to either low temperature or low food availability and that maximum inhibition of reproduction occurred when mice were exposed to both low temperature and low food availability. However, female reproductive activity was inhibited when exposed to low food availability, irrespective of the temperature. Both sexes of mice showed varying abilities to resist fat loss and, in the males, the size of the fat store had a significant effect on reproduction. This varying ability to resist fat loss could be related to levels of activity and in the females (where activity was quantified), high activity scores were significantly associated with reproductive inhibition. These results support the hypothesis that reproduction in Rhabdomys pumilio is opportunistic and controlled by the availability of energy. I propose that the females will be more sensitive to reproductive inhibition due to their far greater post-fertilization responsibilities, where the reproductive activity of the females is rapidly inhibited by a reduction in food availability, while the males are less readily inhibited by low food availability or low temperature, unless the change in the controlling factors is severe enough, or prolonged, at which stage their reproductive activity will cease. The significance of opportunistic reproduction in the seasonal but unpredictable climate of the study area is discussed.
- Full Text:
- Date Issued: 2000
The structure and function of the gametes of the striped field mouse (Rhabdomys pumilio)
- Authors: Tinney, Gregory Michael
- Date: 2000
- Subjects: Gametes , Microtus , Mice
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5774 , http://hdl.handle.net/10962/d1005462 , Gametes , Microtus , Mice
- Description: This study was initiated in an attempt toadd the four-striped field mouse (Rhabdomys pumilio) to the small group of mammals that are used to study and develop assisted reproductive technologies. To accomplish this, a complete knowledge of both the male and female gametes was necessary, as well as a repeatable and successful IVF protocol. The gametes of the field mouse, both the falciformspermand the mature oocytes, were shown to be similar in several respects to those of many other rodent species. The induction of both the capacitated state and the acrosome reaction in the sperm were readily achieved. The success of retrieving mature oocytes was very low, with the rare occurrence of polar bodies within ovulated oocytes. The difficulties with oocytes was either related to the lack of a regular oestrous cycle, or to the hormonal regime used to induce superovulation. Although several protocols were used to accomplish superovulation in this species, it was seldom achieved. In in vitro fertilization trials, sperm were found to attach to both the cumulus oophorus and the zona pellucida of the oocytes. However, fertilization was never accomplished. This failure to achieve fertilization was probably related to the immaturity of the oocytes. Without further studies on Rhabdomys pumilio and further attempts at accomplishing in vitro fertilization, it would seem that this species would not easily be introduced as an animalmodelfor assisted reproduction.
- Full Text:
- Date Issued: 2000
The diet of the black-backed jackal (Canis mesomelas) and caracal (Felis caracal) in the Eastern Cape, South Africa
- Authors: Bussiahn, Frans Ernst Carl
- Date: 1998
- Subjects: Black-backed jackal -- South Africa -- Eastern Cape , Felis -- South Africa -- Eastern Cape , Jackals -- South Africa -- Eastern Cape , Jackals -- Food , Felis -- Food
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5807 , http://hdl.handle.net/10962/d1006489 , Black-backed jackal -- South Africa -- Eastern Cape , Felis -- South Africa -- Eastern Cape , Jackals -- South Africa -- Eastern Cape , Jackals -- Food , Felis -- Food
- Description: The black-backed jackal (Canis mesomelas) and the caracal (Felis caracal) are considered by most farmers in the Eastern Cape to be responsible for excessive livestock losses (sheep and goats) and are, as such, hunted extensively within the Province. Stomach content analyses of individuals killed during predator control operations indicate that caracal are opportunistic hunters of small to medium-sized mammals, preying predominantly on antelope within farmland. Black-backed jackal are opportunistic omnivores, preying predominantly on livestock and antelope in farmland, while invertebrates and antelope constitute the major food items within a game reserve. The diet of caracal was found to be largely influenced by the age of individual animals with old and young animals being the predominant killers of livestock, whereas black-backed jackal diet is influenced primarily by the social structure exhibited by the species, with male animals exhibiting a marked summer peak in livestock killing, due to the increased energetic demands of parental care associated with a long term pair bond. Two caracal (a sub-adult male and adult female), were radio-tracked within farmland for a total of twelve months, yielding the smallest recorded homerange sizes for the species to date (2.1km² and 1.3km² respectively). No livestock losses were recorded within these homeranges for the duration of the study. These data suggest a relatively high abundance of caracal within Lower Albany and further illustrate that individual animals are capable of preying solely on natural prey species over an extended period, when occurring within livestock farming areas. The analysis of local hunt club records and questionnaires revealed a higher incidence of local black-backed jackal (15.2 PD/Kill), than caracal (34.7 PD/Kill), with a marked seasonal peak in kills, for both species, occurring during summer months. The use of hound packs was found to be more effective in reducing the overall abundance of caracal than black-backed jackal, as this technique was seen to eliminate more adult female caracal than black-backed jackal, during the respective breeding season of each species. Local hunt club owners and farmers were more accurate in identifying problem black-backed jackal (74%), than caracal (59%). Recommendations are presented for minimizing stock losses through the application of selective control of specific problem animals, the use of various control measures and encouraging natural prey abundance.
- Full Text:
- Date Issued: 1998
The reproduction biology of four species of South African dolphins
- Authors: Reddy, Kasturi
- Date: 1996
- Subjects: Dolphins -- South Africa -- Reproduction , Bottlenose dolphin -- Reproduction , Striped dolphin -- Reproduction , Chinese white dolphin -- Reproduction
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5753 , http://hdl.handle.net/10962/d1005441 , Dolphins -- South Africa -- Reproduction , Bottlenose dolphin -- Reproduction , Striped dolphin -- Reproduction , Chinese white dolphin -- Reproduction
- Description: Seasonality of reproduction in common dolphins (Delphinus delphis), bottlenosed dolphins (Tursiops aduncus), striped dolphins (Stenella coeruleoalba) and humpbacked dolphins (Sousa chinensis) was examined using standard light microscope techniques. In the males four stages of testicular development could be identified. Individuals less than 2.26m in length and 105kg in mass had testes that contained small seminiferous tubules (0.048mm ± O.Olmm in diameter) and were classified either as juveniles (gonocytes present) or inactive (no gonocytes). Adults whose testes contained spermatozoa were said to be in late spermatogenesis while those whose testes contained no spermatids or spermatozoa were referred to as being in early spermatogenesis. In the males of D. delphis, T. aduncus and S. chinensis, late spermatogenesis occurred throughout the year and there was no significant difference in the monthly mean seminiferous tubule diameters (p > 0.05) within species. I conclude therefore that in these three species spermatogenesis is aseasonal. No conclusions about seasonality of spermatogenesis could be made for S. coeruleoalba owing to the small sample size. Large Graafian follicles occurred in the ovaries of all four species in most months of the year. However, the presence of Graafian follicles can not be taken as an indication of timing of reproduction since they may be remnants of follicles that have not yet degenerated. In D. delphis, T. aduncus and S. coeruleoalba luteal bodies (corpora albicans or corpora lutea) occurred in most months of the year. Active corpora lutea will be present in all months, in some members of the population, since gestation is approximately 12 months. The sperm structure of D. delphis was examined by scanning electron microscopy. The sperm of D. delphis is essentially similar to that described for two other species of Cetacea (Physeter catodon and Tursiops aduncus), having an ellipsoidally shaped head and a short mid-piece with nine mitochondria. The sperm dimensions for D. delphis were head length, 4.4pm; head width, 2.0pm and mid-piece length, 2.4pm. An analysis of foetal age in D. delphis showed that the majority of the foetuses were conceived in January with birth occurring the following summer (December), suggesting that reproduction is seasonal. Neonates of T. aduncus were found throughout the year suggesting aseasonal reproduction. Foetal material was not available for S. coeruleoalba and S. chinensis. Seasonality of reproduction in the four species of dolphins studied has been discussed in relation to feeding, migration and worldwide distribution of the species.
- Full Text:
- Date Issued: 1996
Reproductive biology of the Egyptian free-tailed bat, Tadarida Aegyptiaca
- Authors: Tsita, Johannes Ngoako
- Date: 1994
- Subjects: Tadarida aegyptiaca -- Reproduction , Bats -- Reproduction
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5754 , http://hdl.handle.net/10962/d1005442 , Tadarida aegyptiaca -- Reproduction , Bats -- Reproduction
- Description: The reproductive biology of Tadarida aegyptiaca was studied using specimens collected in the Cape Province of South Africa. The morphology of the reproductive tract of the species was generally similar to that of other molossids, however, the absence of Cowpers glands was unusual. Spermatogenesis began in February and spermatozoa were released to the cauda epididymis during August and September. Follicular development started in March and culminated with the appearance of Graafian follicles in July. Ovulation probably occurred in August and specimens were pregnant by September. Gestation length was estimated to be four to five months and a single young was born in December. The data suggest that T. aegyptiaca is monotocous and monoestrous.
- Full Text:
- Date Issued: 1994
Immunolocalisation of, and ultrastructural changes in the LH gonadotropes of Miniopterus schreibersii and Rhinolophus capensis (Mammalia: Chiroptera) in relation to their reproductive cycles
- Authors: Bojarski, Christina
- Date: 1990
- Subjects: Bats -- Reproduction
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5589 , http://hdl.handle.net/10962/d1002039
- Description: LH gonadotropes are successfully identified in the anterior pituitary of Minioptems schreibersii and Rhinolophus capensis, using immunogold labelling at the light and electron microscopy level. The gonadotropes are oval to polygonal in shape and possess numerous small secretory granules, which contain LH throughout the year. Their distribution is similar in both species, although the abundance varies slightly between species and sexes. Seasonal changes are detected in gonadotrope ultrastructure, pituitary LH levels, and plasma hormone levels, and activity pattern of LH gonadotropes generally coincide with reproductive activity in both bat species. In female M. schreibersii gonadotrope activity, pituitary LH, and plasma LH levels coincide with development, implantation and gestation. During the delayed implantation gonadotropes are inactive and and high follicular period of plasma LH levels are low, coinciding with corpus luteum inactivity and low plasma progesterone levels. Implantation coincides with increased activity of the gonadotrope activity, increased plasma LH levels, reactivation of the corpus luteum and elevated plasma progesterone levels. Activation of LH gonadotropes towards the end of hibernation may be initiated by the winter solstice, which marks the change to increasing daylength. In female R capensis gonadotrope activity and high pituitary and plasma LH levels occur towards the end of follicular development. During hibernation gonadotrope activity and plasma LH levels decrease. Ovulation coincides with increasing gonadotrope activity (which follows the winter solstice), although a preovulatory peak in plasma LH is not detected. In male M. schreibersii and R. capensis, gonadotrope activity and high plasma LH and testosterone levels coincide with spermatogenesis, except during a period of reproductive inactivity in spring in male M. schreibersii, where gonadotropes appear active and plasma LH and testosterone levels are high. The reason for this apparent activity is not known. Male sperm storage during hibernation in male R. capensis coincides with low gonadotrope activity and low plasma LH and testosterone levels. Factors initiating gonadotrope activity and hence spermatogenesis are probably decreasing daylength (summer solstice) in M. schreibersii and increasing ambient temperatures and food abundance (following the hibernation period) in R.capensis.
- Full Text:
- Date Issued: 1990
Seasonal changes in the physiological and hormonal aspects of reproduction in the male long-fingered bat, Miniopterus schreibersii (Mammalia : Chiroptera)
- Authors: Paton, Joy Carol
- Date: 1989
- Subjects: Bats -- Reproduction
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5590 , http://hdl.handle.net/10962/d1002040
- Description: The reproductive cycle of Miniopterus schreibersii is modified as a consequence of a period of torpor/hibernation over the winter months. This bat is one of three genera which employ the reproductive strategy of delayed implantation in which the blastocyst remains free in the uterine lumen during the winter months. Spermatogenesis is initiated in February, with spermiogenesis occuring in March. Copulation, ovulation and fertilization takes place between March and May after which the testes regress and remain in an inactive condition until the following summer. Activity in the accessory gland complex is initiated in March and continues until early June. Plasma testosterone concentrations reach a peak in May, decline over the winter months and reach a second, unexplainable peak in October. Leydig cells are secretorily active in February/early March after which they undergo vacuolation and final degeneration. The question of the life cyle of Leydig cells is addressed and an increase in a certain cell after Leydig cell activity suggests that this cell type may be the precursor of Leydig cells.
- Full Text:
- Date Issued: 1989