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Reproductive hormones and behaviour in the Indian (rhinoceros unicornis) and Sumatran (Dicerorhinus sumatrensis) rhinoceros /McIninch, Merryn. January 2003 (has links)
Thesis (M.Sc.)--York University, 2003. Graduate Programme in Biology. / Typescript. Includes bibliographical references (leaves 114-120). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://wwwlib.umi.com/cr/yorku/fullcit?pMQ86299
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Capture and boma stress responses in the white rhinoceros (Ceratotherium simum)Kruger, Marius January 2017 (has links)
A thesis submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree Doctor of Philosophy.
Johannesburg 2017 / The translocation of rhinoceroses is extremely stressful to the animal and this may strongly affect the success of translocation. The objectives of this study in white rhinoceroses were to (i) validate a non-invasive assay using faecal metabolites to assess the stress response in the white rhinoceros, (ii) to assess the stress response in the white rhinoceros associated with capture, handling, transportation and confinement, to be able to predict at capture which animals will adapt to confinement, and (iii) to investigate the use of the acute phase proteins (APP), serum amyloid A (SAA) and haptoglobin (Hp) as indicators of stress associated with capture and confinement. To achieve these objectives blood and faecal samples were collected from each rhinoceros at capture, and whenever possible, during confinement. To assess the hypothalamic-pituitary-adrenocortical axis (HPA) response of white rhinoceroses an ACTH challenge was performed and plasma cortisol and faecal glucocorticoid metabolites (FGM) were measured with a commercially available 125I RIA kit and a 125I corticosterone RIA kit, respectively. Gastrointestinal transit time was estimated with the use of an inert marker. Results showed a 4-to 8-fold increase in plasma cortisol within 15 to 20 minutes and a 3-fold increase in FGM concentration 60 to 90 hours later. Although this FGM measurement is non-invasive, relevant and robust, the time required to complete the extraction and assay could take several days. This measurement can be advantageous to monitor the stress of animals in confinement but has no application where animals are captured and immediately translocated. Measurement of plasma cortisol and FGM was also used to assess stress in rhinoceroses following transportation and in confinement. The results show that rhinoceroses have variable individual responses to capture and confinement and although there was evidence of behavioural habituation, HPA activity showed that there was no physiological habituation. We could not establish any predictor of success of habituation in the boma environment. The APP results showed that Hp is more likely to be an indicator of metabolic stress; rather than physical and psychological stress; while SAA responds rapidly to physical and psychological stress in the rhinoceros. It was also found that plasma cortisol was positively
associated with SAA concentration when the animal is transferred to the boma, and that SAA may be a potential plasma biomarker to identify animals which could be at risk of failing to habituate to confinement. / MT 2018
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Adaptive resource use in a re-introduced black rhinoceros populationShaw, Joanne Aileen 14 September 2011 (has links)
Ph. D, Faculty of Science, University of Witwatersrand, 2011 / The aim of biological management for black rhinoceros (Diceros bicornis)
conservation is to maximise meta-population growth rates to aid species recovery. This
research investigated how adaptive resource use in response to seasonal variation in
resource availability could affect maximum productive habitat capacity for this critically
endangered species. Analysis was based on a population of rhinos which had shown
excellent annual growth rates and low inter-calving intervals since re-introduction to
Tswalu Kalahari Reserve in the Northern Cape of South Africa in 1995.
Acacia haematoxylon, a semi-evergreen species, was identified as the key
resource forming the majority of diet contents during the late dry season. Use of this
species resulted in a low level of seasonal variation in dietary contents of energy and
protein. During the data collection period, energy and protein gains of individual female
rhinos were estimated to exceed maximum requirements for reproduction throughout the
seasonal cycle. An experiment designed to test the compensatory growth response of A.
haematoxylon found that clipping trees in a way that simulated rhino browsing stimulated
an increased growth response in the following wet season. This response indicated
potential for a facilitatory relationship in the short term. A large proportion of the
available area at Tswalu was not used by black rhinos. Home range location and habitat
type selection within home ranges during the dry season were positively associated with
two shrubveld habitat types containing greater A. haematoxylon biomass than other
habitat types. Results from all aspects of field data analysis emphasized the importance
of A. haematoxylon as the key dry season resource for black rhino at Tswalu.
Field data were used to develop a conceptual model of how seasonally adaptive
resource use by black rhinos could determine maximum productive habitat capacity. The
crux of the model was to estimate the highest population density at which female rhinos
could attain maximum energetic gains for reproduction throughout the entire seasonal
cycle. The most limiting period was the nutritional bottleneck during the late dry season.
The rationale behind this approach was to enable females to maintain body condition and
be capable of meeting nutritional requirements for reproduction throughout the year, thus
minimizing inter-calving intervals and maximising population growth rates. Model
projections indicated that female rhinos could not attain energy gains for reproduction
throughout the dry season in certain habitat types due to low availability of A.
haematoxylon. However, model outputs indicated potential for an increase in rhino
density by approximately one third in the two favoured shrubveld habitat types, assuming
that habitat conditions remained unchanged.
Availability of semi-evergreen A. haematoxylon was identified as the key
vegetation component determining maximum productive habitat capacity for black rhino
at Tswalu. Monitoring available biomass of this species at the end of the dry season
could provide a simple plant-based indicator of how close the population is to maximum
productive habitat capacity. Managing rhino densities in fenced reserves elsewhere
around spatial and temporal availability of key resources may assist in achieving black
rhino conservation goals of maximising metapopulation growth rates.
Joanne Aileen Shaw
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The Rhinoceros in 2006: A Dramaturgical Analysis of Eugene Ionesco’s <i>Rhinoceros</i>Kemock, Kathleen Clare 20 April 2007 (has links)
No description available.
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Parentage analysis in a free-ranging, closed population of southern white rhinoceros : genetics, pedigrees and managementGuerier, Abigail Sarah 08 November 2012 (has links)
Small populations of animals are vulnerable to the consequences of breeding within a closed group – inbreeding depression and genetic drift lead to reductions in genetic variability, which in turn can give rise to the amplification of deleterious traits. Traditionally, managers attempt to minimise these effects by controlling the genetic structure via a manipulation of the paternal line, in the case of rhinos usually by translocation of breeding and sub-adult bulls. This strategy depends on having access to detailed pedigree data, and, in particular, some knowledge of the parentage of the offspring within the population. This information is particularly difficult to obtain in long-lived, free-ranging populations (particularly for rare and endangered species) where the identity of the father must be inferred from behavioural observations, and often the identity of the mother cannot be determined once juveniles have dispersed. In this thesis I present the results of a study to determine the parentage within a free-ranging, enclosed population of southern white rhinoceros (Ceratotherium simum simum) located on Ongava Game Reserve (OGR) in the north of Namibia. I used genetic techniques to obtain a genotype for each animal in the population, and then used detailed reserve management records from the period 1993-2009 to constrain the statistical process of parentage assignment. Using these different methods, I was able to assign both parents for 22 of 23 offspring with 80% confidence (16 of 23 at 95% confidence, mother only in 1 of 23), making this study the first to successfully complete a comprehensive parentage analysis in a free-ranging population of southern white rhinoceros. The key to the success of this study was a combination of accurate pedigree data and a complete set of genotype data. The parentage assignments allowed me to construct a complete lineage diagram for each of the founder matrilines, and further analyse the status and reproductive success of the population. OGR’s southern white rhinoceros population is expanding at close to 14%, well over the expected maximum growth rate for rhinoceros metapopulations (9%). The mean inter-calf interval is about 2.2 years and average age at first parturition is 6 years, indicating good fecundity. Conception is strongly seasonal, occurring mainly (89%) during the rainy season. The current management practice is to replace dominant bulls after their breeding tenure, and also to remove all young bulls from the population before they reach breeding age (with the aim to restrict potential inbreeding). Only one calf of seven in the F2 generation is inbred. My analysis indicates that, at least in the 2006 cohort of eight calves, founder females bred only with the founder male, while offspring females (F1 generation) bred only with introduced males. This suggests some form of mate selection leading to inbreeding avoidance within the population. Finally, there is some evidence that certain matrilines exhibit/experience different reproductive potential (daughters in one matriline exhibit longer inter-calving intervals and male bias in calf birth sex ratios). These details indicate that genetic data provide valuable information for management. When reviewing management decisions to date, I found that one of the founder bulls was the more successful in terms of calves sired (10 of 13). Management had, however, selected the other founder bull for removal by sale based on the assumption that he was behaviourally dominant and territorial and therefore likely to have been more successful at breeding. I also found that introduced bulls were breeding successfully before they appeared to have established territories. Thus these findings challenge the assumption that male white rhinoceros reproductive success is related to dominant, territorial behaviour. I conclude that in order to optimally manage small, free-ranging enclosed populations of southern white rhinoceros it is essential to have reliable and accurate pedigree data (this includes a methodology for identifying individual rhino), as well as genetic data for the entire population. I recommend that conservation management programmes for rhinoceros populations incorporate both genetic and demographic data. This will allow for the development of white rhinoceros population management strategies that attempt to optimize genetic diversity and population health, and benefit the establishment of new, robust populations. Translocations of animals are an important aspect of meta-population management of rhinoceros and data which provides accurate insight into the true mating system and reproductive success within a population allows for the correct selection of individuals for this process. Copyright / Dissertation (MSc)--University of Pretoria, 2012. / Zoology and Entomology / Unrestricted
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Disturbance and habitat factors in a small reserve : home range establishment by black rhinocerous (diceros bicornis minor)Odendaal, Karen 18 January 2012 (has links)
MSc., Faculty of Science, University of the Witwatersrand, 2011 / Black rhinos are being moved to small protected areas in an attempt to expand their range;
and factors commonly found within these small protected areas could influence black rhino
ecology. From the literature we understand how biological factors affect rhino resource
selection but not in the context of small reserves. This study investigates the home range
establishment of black rhinos and those factors commonly associated with small reserves
that affect rhino habitat-use as well as weigh the relative importance of each of them. The
factors considered were human disturbances such as residences, lodges, roads and fences,
slope, elevation, perennial water, burnt areas and vegetation type. Minimum convex
polygon, 50% core and 95% local convex hull (LoCoH) was used to generate home ranges
from sightings data collected for 17 individuals. The mean 95% LoCoH home range was 3.77
km² (95% CI: 2.92- 4.63, n=17), and is comparatively small in relation to the adaptive kernel
home ranges of previous studies. A use-availability resource selection function showed that
black rhinos avoided areas close to residences, lodges, camps, and perennial water, and
these variables played a bigger role than their selection for thicket vegetation. These factors
have a highly significant effect on rhino resource selection, and this effect is magnified due
to the density of human disturbances and water points commonly found in small reserves.
It is essential that this knowledge be applied in the management of reserves protecting
black rhinos.
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The Rhinoceros in 2006 a dramaturgical analysis of Eugene Ionesco's Rhinoceros /Kemock, Kathleen Clare. January 2007 (has links)
Thesis (M.A.)--Miami University, Dept. of Theatre, 2007. / Title from first page of PDF document. Includes bibliographical references (p. 36-37).
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THE UTILITY OF DNA MICROSATELLITE MARKERS IN CONSERVATION OF A NAMIBIAN POPULATION OF THE BLACK RHINOCEROS (DICEROS BICORNIS)Kim, MICHAEL 01 June 2009 (has links)
Massive declines in the latter half of the 20th century left black rhinoceros populations perilously close to extinction with only approximately 3600 individuals remaining, in contrast to estimated census numbers of over 100,000 individuals in 1900. While Diceros bicornis bicornis is the second most abundant subspecies of black rhino, behind D. b. minor, relatively few genetic studies have focused on this taxon. I used polymorphic DNA microsatellite markers to describe population structure in this subspecies. Using these genetic markers, the goals of this study were: i) to characterize the genetic variability of D.b. bicornis individuals (n = 170) found in Etosha National Park, Namibia, using seven DNA microsatellite markers, ii) to determine if there is population structure within Etosha National Park, using both traditional Wright’s F-statistics and a Bayesian model that requires no a priori population assignment, iii) to determine relatedness amongst founding and newly introduced black rhinoceroses held in private game farms throughout Namibia, using moment estimators of relatedness; and iv) to determine parentage of game farm rhinos with partial or no pedigree data available, using likelihood-based methods. I found that: i) the levels of genetic diversity in D.b. bicornis from Etosha National Park are consistent with previously published studies using microsatellite markers, and are relatively high; ii) the population structure within Etosha National Park is ambiguous using traditional F-statistics, but can be subdivided into three diagnosable clusters (western, central and eastern) using a Bayesian approach; iii) a relatively high degree of relatedness exists among founding members of game farm rhinos; and iv) assignments of parentage had greater success when there were fewer candidate parents and support the notion that black rhinoceroses are polygynous. / Thesis (Master, Biology) -- Queen's University, 2009-06-01 10:18:14.064
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Food preferences and feeding interactions among browsers and the effect of an exotic invasive weed Chromolaena odorata on the endangered black rhino (Diceros bicornis), in an African savanna.Howison, Ruth Alison. January 2009 (has links)
Biodiversity changes, often resulting from climate change, land transformation, and the
transportation of organisms across geographical barriers are among the most important human
induced global changes. To optimize the spatial allocation of conservation efforts, and how to
best protect indigenous species, requires an understanding of the principal determinants that
structure ecological communities and ecosystems. We studied community-level interaction
among a diverse assemblage of specialist and generalist browsers in an African savanna.
Hluhluwe-iMfolozi Park (HiP), South Africa, hosts a complete assemblage of vertebrate species
across all trophic levels and contains a diverse guild of large browsers. Using species abundance
distributions (SADs) we graphically illustrate the diversity and abundance of woody species that
comprise six structural habitat types within HiP. We calculated the Shannon-Wiener index and
Pianka’s niche overlap to characterise the utilization of forage across habitat types among
different browser groups. By using individual plant traits we investigated mechanisms of
resource partitioning. We specifically investigated the effect of the temporal expansion of an
exotic invasive plant (Chromolaena odorata) on the critically endangered black rhino using GIS
and statistical analyses. We found that lower lying habitat types were important forage resources
for browser species and individual plant traits that are highly correlated with digestibility
strongly predicted browser preference. Black rhino used different strategic and metabolic
mechanisms to successfully compete within the same forage height range of other, smaller,
browsers. C. odorata has negatively impacted forage species utilization and has led to a spatial
reorganization of the population of black rhino. This may partly explain the recent decline in the
population. The principles within metapopulation management can be used to successfully
conserve endangered species. High diversity of browse across three dimensions (diversity,
abundance and maximum height) relative to area facilitates a high diversity and abundance of
different browsing herbivores. Therefore the spatial configurations of resources ranging from
topological attributes to the individual plant traits are essential to maintaining viable populations
of many co-occurring species within conservation areas of limited extent. / Thesis (M.Sc.)-University of KwaZulu-Natal, 2009.
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Epidemiology of black rhinoceroses (Diceros bicornis) in captivity in the United StatesDennis, Patricia Marie. January 2004 (has links)
Thesis (Ph. D.)--Ohio State University, 2004. / Document formatted into pages; contains xiii, 126 p. Includes bibliographical references. Abstract available online via OhioLINK's ETD Center; full text release delayed at author's request until 2007 Sept. 21.
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