Thesis (MScConEcol) Stellenbosch University, 2012. / ENGLISH ABSTRACT: The decline of sable antelope through much of the lowveld region of Zimbabwe and South Africa has become an issue of concern for wildlife managers. On Malilangwe Wildlife Reserve (MWR) alone, sable numbers crashed from 237 animals in 1994 to only 62 by 2005. The purpose of this study was to determine the cause of the decline and the continued lack of success in the sable population. The study had three specific aims: 1) to assess the current viability of the sable population at MWR and understand the sensitivity of the population to environmental changes, 2) to gain an understanding of the space-use and habitat selection of sable at the landscape scale, and 3) to speculate on the possible causes of the decline in sable antelope numbers at MWR. GPS collars were fitted to four sable herds at MWR and a fifth herd was monitored opportunistically over the study period. From these, life history data were collected and fed into a VORTEX population viability model to assess the current viability of the sable population at MWR. Vital rates input into the model were then manipulated, simulating the effect of natural pressures placed on the population. A sensitivity analysis was used to determine the sensitivity of the population to these natural pressures, using the long term growth rate as a relative measure of overall fitness. The results suggest the current population will remain extant but that natural pressure placed on the adult female segment of the population could have a drastic impact on the success of the sable population. The evidence indicates that the decline in sable numbers at MWR must have been driven by an increase in mortality in the adult segment of the population. The GPS collars gave regular fixes enabling the development of a spatial pattern of home-range and habitat use over time. LoCoH was used to develop seasonal home ranges and utilization distributions for the sable herds at MWR. A multiscale approach was used to investigate habitat selection by sable over time at MWR, using a Bonferonni Z-statistic, time series graphs and Maximum Entropy modeling. Sable used much larger ranges during the early wet season than during any other season at MWR and were highly selective at the broad scale spending more than 92% of their time foraging on the nutrient rich basalt derived soils. At the finer scale sable generally chose for areas characterized by a well developed grass layer on shallow calcareous soils moving onto areas of deeper clay rich soils during the dry season and consistently made use of areas further than average from water. Data from the collars were then used to conduct bi-monthly tick drags along the sable foraging paths to assess the level of tick challenge faced by each herd over time and this was related back to the survival rate of calves within each herd using linear regressions. The effects of predation were assessed again using the GPS collar data and a novel method of determining predation risk using motion sensor camera traps. The level of predation risk was then related back to the survival rate of each age class in the sable population. The long term effects of predation on the sable population was investigated using historical data on sable carcasses discovered and the annual rate of population decline. These were regressed against lion population numbers to determine whether any relationship existed between lion population numbers and the rate of population decline. Tick challenge had no effect on the survival of sable calves and the overall tick challenge at MWR was extremely low during the study period. Predators however seemed to have an impact on the sable population in a number of ways. Hyaena’s seemed to have a major impact on the survival of sable calves, particularly during the first few weeks of life and lion numbers showed a strong relationship with the overall rate of population decline. Sable antelope are highly susceptible to predators and lions seem primarily to blame for driving the decline in the species at MWR. The relationship is however not entirely clear and evidence suggests that a number of variables including vegetation cover and water distribution play a role in determining the impact that predators have on sable populations.

A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfillment of the requirements for the degree of Masters in Science. Johannesburg, September 2017. / Sable antelope numbers have been declining in protected areas of South Africa and they are listed as Vulnerable in the National Red List Assessment. In Kruger National Park, since 1986, the abundance of sable antelope has declined from 2240 to just under 400 individuals in 2014, making them at risk of local extirpation. The aim of the study was to explore some of the possible explanations, not explored before, for sable antelope (Hippotragus niger) perceived decline in the Kgaswane Mountain Reserve (KMR), in the North-West Province of South Africa. I therefore looked at assessing sable antelope use of space in relation to ‘high risk’ areas as determined by distances to fences, campsites and roads; determining the seasonal variations in the nutritional status of sable antelope; estimating calves recruitment, survival and population sex ratio. To achieve these objectives two sable antelope heifers were collared in the reserve, one from the ‘vlei’ herd and one from the ‘woodland’ herd. Both herds avoided ‘high risk’ areas, especially areas close to camping huts. The herds made little use of areas where there was lots of human movement. I expected the herds to utilise areas close to fences, especially after security burns along the perimeter of the park, but that was not the case as these areas were little utilised. Both herds preferred the tall grassland type of vegetation. As expected both herds utilised burnt areas and the woodland herd used these areas more than the vlei herd. Faecal crude protein and faecal phosphorus values during the dry season were higher compared to a previous study in KMR, which seems to suggest that currently the sable population in KMR is doing better compared to 2002-2003. Since 2011 until 2014, there were a total of 34 calves born with 15 missing after the study but only one mortality recorded. Therefore the reasons for the missing calves are still unclear. The best way to monitor survival of populations for long term studies would be to mark individuals in a population but unfortunately this was impossible for this study. I expected more females to be born as compared to males and this was not the case as there were more males (20) born than females (14), further indicating that potentially currently the population is doing better than in the past. / MT2018

The annual demography of a population of antelope ground squirrels in Curlew Valley, Utah was studied by measuring population density, natality, and mortality. Capture- recapture techniques yielded lower estimates than the Hayne strip- census. The estimates suggested 1968 was a year of population decline. One hundred seventy- three squirrels were collected and autopsied to obtain sex ratio , age structure, natality, and mortality data . The seasonal sex ratios for adult and yearling squirrels showed 82 percent females in spring 1968, this gradually changed to 56 percent by winter . The seasonal sex ratios of the young squirrels showed 59 percent females upon emergence from natal burrows in summer 1968, increasing to 79 percent by winter. The squirrels collected were aged by cementum annuli . The oldest were believed to be 5 years old . They composed 1.2 percent of the collection while young- of- the-year composed 38. 7 percent. The estimate of mean corpora lutea was 7.6, the mean embryo count was 7.2, and the mean post-partum placental scar count was 5.8. The mean corpora lutea count for yearlings was statistically lower than the count for adults and the mean ovulation rate for 1968 statistically lower than the rate for 1969. An estimate of litter size from four nests gave a mean of 4.5. In 1968, the conception rate was 91 percent with yearlings comprising 75 percent of those not conceiving. In 1969, the rate was 100 percent. Pre-Emergence mortality of the young was 41 percent. post-emergence mortality was 86 percent, and mortality, March - November, 1968 was 92 percent. Adult and yearling spring-to-spring mortality for study area squirrels calculated from retrap data was 81 percent. Spring-to-spring mortality calulated from age distribution data and Ricker's formula was 71 percent. The spring-to-fall mortality for 1968 calculated from density estimates and age distribution data was 53 percent.

Thesis (M.S.)--Oregon State University, 2002. / Typescript (photocopy). Includes bibliographical references (leaves 38-45). Also available online.

Theileria species (sable) causes significant mortalities in roan (Hippotragus equinus), and to a lesser extent, sable antelope (Hippotragus niger) yearly. Treatment of the condition and an ‘infect and treat’ vaccination method using a tick-derived stabilate both rely on the availability of buparvaquone, a naphthoquinone with anti-theilerial activity. As buparvaquone is a controlled drug which is not commercially available in South Africa, a viable commercial alternative prevention or treatment method is necessary to control this disease. This study explores the effectiveness of an alternative vaccination method using Theileria sp. (sable) infected in vitro cultured leukoblasts. A Theileria sp. (sable) containing cell line was initiated from lymph node biopsy material of an infected roan antelope and the parasite was successfully propagated in vitro. Attenuation is believed to have been achieved by 16 cycles of passage. Real time PCR suggests that the parasite was successfully transmitted via subcutaneous inoculation with this cell line to two naïve roan antelope. These two inoculated animals remained clinically unaffected by challenge with a tick stabilate used in the ‘infect and treat’ vaccination method. In contrast, the two unvaccinated control animals became clinically ill and required buparvaquone treatment after challenge. This pilot study provides enough evidence to encourage further investigation in the use of Theileria sp. (sable) infected cells as a potential vaccine. A field study involving more animals which are challenged by natural infection after inoculation is the proposed next step. / Dissertation (MMedVet)--University of Pretoria, 2010. / Paraclinical Sciences / unrestricted

The aim of this study was to determine the species composition of questing ixodid ticks on the vegetation in intensive breeding enclosures for sable antelopes (Hippotragus niger), on which strategic tick control is practiced, and to compare it with that of questing ixodid ticks in a multi-species herbivore enclosure surrounding the breeding enclosures, and where no tick control is practiced. A total of eight ixodid tick species were collected namely, Amblyomma hebraeum, Amblyomma marmoreum, Haemaphysalis elliptica, Rhipicephalus appendiculatus, Rhipicephalus decoloratus, Rhipicephalus evertsi evertsi, Rhipicephalus simus and Rhipicephalus zambeziensis. A. marmoreum was only collected in the intensive breeding enclosures and H. elliptica only in the multiple herbivore species enclosure, whilst the remaining tick species were collected in both enclosures. The study was also designed to determine the abundance, seasonal abundance and proportion of ixodid tick larvae collected in the sable antelope breeding enclosures as well as in the multi-species herbivore enclosure and to compare the population dynamics of tick species in the respective enclosures with particular emphasis on R. decoloratus. R. decoloratus accounted for 65.4% of the total number ticks collected in the sable enclosures, whilst it represented only 24.3% of the total number of ticks collected in the multi-species herbivore camp. R. decoloratus was more abundant than A. hebraeum and R. appendiculatus in the woodlands of the sable antelope enclosures whilst R. decoloratus and R. evertsi evertsi were more abundant in grassland habitats of the sable antelope enclosures than both A. hebraeum and R. appendiculatus. R. decoloratus larvae were collected throughout the year with peak collections in November 2012 and between October and December 2013 in the sable breeding enclosures, and in April and May 2012 and February and April 2013 in the multi-species herbivore enclosure. The numbers of R. decoloratus larvae collected in the sable breeding enclosures increased significantly during the study period (p≤0.020). / Dissertation (MSc)--University of Pretoria, 2014. / gm2014 / Veterinary Tropical Diseases / unrestricted

Throughout the history of traditional land use planning, justification for allocating a land use for a particular area has been accomplished generally in a debilitated fashion. For example, decisions have generally been arrived at by (1) political process--incorporating fringe areas into present land use patterns, or (2) short-term revenue producers are given a land use change from a tax base incentive, or (3) revelations implemented, or other subjective justifications. Except in very few instances, data used to base land use planning decisions was not accurately interpreted for adequate input or not even gathered. Recently, new and innovative methods for land use planning processes have evolved to gather, interpret and measure data more accurately. More notable processes have been developed by Ian McHarg, Peter Jacobs, Phillip H. Lewis, G. Angus Hills, David Stinton and Carl Steinitz. David Stinton and Carl Steinitz developed a program called "GRID" which basically utilizes the computer as a tool to process data and display data through computer graphics as maps. The process implemented in this project to compile and graphically display data was the GRID computer program. The program utilized Utah State University's Burroughs 6700 digital computer. This system has been found to be faster and more economical than the traditional method of overlays without sacrificing accuracy. Utilizing computer graphic techniques, this project conducted a detailed environmental inventory and analysis of Antelope Island, Utah. Various land use activities were evaluated for their potential impact upon certain natural systems of the island. The major objective of this thesis is to provide, for interested levels of government and concerned citizens, guidelines for land use planning that will assist them in making more meaningful and accurate decisions of present and future land use in the study area. This project established recreational guidelines for Antelope Island, Utah, and acts as a study model for recreational land use planning for the cold desert biome states of Arizona, Nevada, and Utah. The study is an environmental analysis and attempts to recognize problem areas sensitive to development. Guidelines deal directly with maximizing recreation potential of the island while minimizing impacts on natural systems such as vegetation, wildlife and soil erosion.

This study focused on how changes in food availability during the dry season, influenced various aspects of sable (Hippotragus niger niger) foraging and social ecology. The main purpose of this was to determine whether differences in their foraging ecology explained the reduction in population size compared to other more abundant herbivores (e.g. zebra, buffalos, hartebeest). Contrary to expectation, sable did not limit their foraging to woodlands, but also fed in open grasslands, provided these retained green grass during the dry season. Wetlands were key resource areas during the dry season, but sable did not limit their feeding to these bottomland areas. They also fed on hill slopes and upper plateaus that had been burnt. During the study, sable were attracted to burnt areas despite the reduced grass availability. My study highlights how these burnt areas were important in alleviating nutritional deficiencies during the dry season. At lower spatial levels, I looked at the factors that influenced the selection of feeding areas and plant species. Like other grazers, sable were attracted to green leaves but did not avoid brown leaves or stems. Grass species eaten were the same as those preferred by most domestic and wild grazers. Surprisingly, adult males stayed with the breeding herds despite their different activity budgets. Unlike most other African grazers, sub adult sable males did not form bachelor groups. Instead, they stayed within the breeding herds the whole time and had a similar activity budget to females. As adult males moved with the breeding herds, I was able to examine the costs and benefits involved with such a social structure. From this, I was able to relate my results to the bigger picture of factors influencing sexual segregation in ungulates. In conclusion, sable utilised a wide variety of habitat types and adjusted their foraging behaviour to accommodate different seasonal situations. I was unable to find anything in their feeding ecology that could explain the continued decline in population size. Therefore, I suggest that future research needs to focus on other potential causes such as a higher susceptibility to predation and disease as compared to more abundant herbivore species.

A series of severe and prolonged droughts occurred throughout the Northern Hemisphere between approximately 1150 BP to 600 BP. This phenomenon is referred to as the Medieval Climatic Anomaly and has been shown to have differentially impacted various regions of the world. Previous studies have suggested causal links between the Medieval Climatic Anomaly and observed culture change. The goal of this study was to examine the Antelope Valley region of the Mojave Desert for evidence of impacts on human populations related to the Medieval Climatic Anomaly. To achieve this goal, a sample selection of archaeological sites was chosen from lands within Edwards Air Force Base. These sites represented occupations which occurred immediately before, during, and after the Medieval Climatic Anomaly. Site assemblages were analyzed and compared by cultural period, with cross-comparisons made of artefactual and ecofactual constituents. Site densities and areal extents were also examined and compared. These analyses showed the emergence of trends concurrent with the introduction of the Medieval Climatic Anomaly. The data supports the hypothesis that humans who populated the Antelope Valley region of the Mojave Desert during this period may have engaged in population aggregation, with a tethered nomadism subsistence strategy. The data also shows evidence that upon the amelioration of the environment after the Medieval Climatic Anomaly, site characteristics within the region saw a significant shift. While the evidence generated by this study does suggest a link between climatic change experienced during the Medieval Climatic Anomaly and change observed within the archaeology of the Antelope Valley, it does not suggest climate as a sole, or even primary, causal factor. Rather, the intent of this study was to identify one possible variable responsible for observed change that occurred in the region. With this in mind, the Medieval Climatic Anomaly was found to have been significant enough to have either directly or indirectly impacted the prehistoric occupants of the study region.

Thesis (Ed. D.)--UCLA, 2008. / Vita. Description based on print version record. Includes bibliographical references (leaves 113-118).