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Analýza chovu levharta skvrnitého (Panthera pardus ssp.) v České republice a na SlovenskuVašák, Jan January 2009 (has links)
No description available.
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Interrelationships between the larger carnivores of the Klaserie private nature reserve with special reference to the leopard Pantera pardus (Linnaeus, 1758) and the cheetah Acinonyx jubatus (Schreber, 1775)Kruger, John Ernst 03 October 2007 (has links)
Please read the abstract in the section 00front of this document / Dissertation (MSc (Wildlife Management))--University of Pretoria, 2007. / Zoology and Entomology / MSc / Unrestricted
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Immunogenetics of free-ranging felids on Namibian farmlandsCastro Prieto, Aines del Carmen January 2011 (has links)
Genetic variation is crucial for the long-term survival of the species as it provides the potential for adaptive responses to environmental changes such as emerging diseases. The Major Histocompatibility Complex (MHC) is a gene family that plays a central role in the vertebrate’s immune system by triggering the adaptive immune response after exposure to pathogens. MHC genes have become highly suitable molecular markers of adaptive significance. They synthesize two primary cell surface molecules namely MHC class I and class II that recognize short fragments of proteins derived respectively from intracellular (e.g. viruses) and extracellular (e.g. bacteria, protozoa, arthropods) origins and present them to immune cells. High levels of MHC polymorphism frequently observed in natural populations are interpreted as an adaptation to detect and present a wide array of rapidly evolving pathogens. This variation appears to be largely maintained by positive selection driven mainly by pathogenic selective pressures.
For my doctoral research I focused on MHC I and II variation in free-ranging cheetahs (Acinonyx jubatus) and leopards (Panthera pardus) on Namibian farmlands. Both felid species are sympatric thus subject to similar pathogenic pressures but differ in their evolutionary and demographic histories. The main aims were to investigate 1) the extent and patterns of MHC variation at the population level in both felids, 2) the association between levels of MHC variation and disease resistance in free-ranging cheetahs, and 3) the role of selection at different time scales in shaping MHC variation in both felids. Cheetahs and leopards represent the largest free-ranging carnivores in Namibia. They concentrate in unprotected areas on privately owned farmlands where domestic and other wild animals also occur and the risk of pathogen transmission is increased. Thus, knowledge on adaptive genetic variation involved in disease resistance may be pertinent to both felid species’ conservation.
The cheetah has been used as a classic example in conservation genetics textbooks due to overall low levels of genetic variation. Reduced variation at MHC genes has been associated with high susceptibility to infectious diseases in cheetahs. However, increased disease susceptibility has only been observed in captive cheetahs whereas recent studies in free-ranging Namibian cheetahs revealed a good health status. This raised the question whether the diversity at MHC I and II genes in free-ranging cheetahs is higher than previously reported. In this study, a total of 10 MHC I alleles and four MHC II alleles were observed in 149 individuals throughout Namibia.
All alleles but one likely belong to functional MHC genes as their expression was confirmed. The observed alleles belong to four MHC I and three MHC II genes in the species as revealed by phylogenetic analyses. Signatures of historical positive selection acting on specific sites that interact directly with pathogen-derived proteins were detected in both MHC classes. Furthermore, a high genetic differentiation at MHC I was observed between Namibian cheetahs from east-central and north-central regions known to differ substantially in exposure to feline-specific viral pathogens. This suggests that the patterns of MHC I variation in the current population mirrors different pathogenic selective pressure imposed by viruses. Cheetahs showed low levels of MHC diversity compared with other mammalian species including felids, but this does not seem to influence the current immunocompetence of free-ranging cheetahs in Namibia and contradicts the previous conclusion that the cheetah is a paradigm species of disease susceptibility. However, it cannot be ruled out that the low MHC variation might limit a prosperous immunocompetence in the case of an emerging disease scenario because none of the remaining alleles might be able to recognize a novel pathogen.
In contrast to cheetahs, leopards occur in most parts of Africa being perhaps the most abundant big cat in the continent. Leopards seem to have escaped from large-scale declines due to epizootics in the past in contrast to some free-ranging large carnivore populations in Africa that have been afflicted by epizootics. Currently, no information about the MHC sequence variation and constitution in African leopards exists. In this study, I characterized genetic variation at MHC I and MHC II genes in free-ranging leopards from Namibia. A total of six MHC I and six MHC II sequences were detected in 25 individuals from the east-central region. The maximum number of sequences observed per individual suggests that they likely correspond to at least three MHC I and three MHC II genes. Hallmarks of MHC evolution were confirmed such as historical positive selection, recombination and trans-species polymorphism. The low MHC variation detected in Namibian leopards is not conclusive and further research is required to assess the extent of MHC variation in different areas of its geographic range.
Results from this thesis will contribute to better understanding the evolutionary significance of MHC and conservation implications in free-ranging felids. Translocation of wildlife is an increasingly used management tool for conservation purposes that should be conducted carefully as it may affect the ability of the translocated animals to cope with different pathogenic selective pressures. / Genetische Variabilität ist entscheidend für das langfristige Überleben von Arten, denn es ermöglicht dem Organismus sich Umweltveränderungen, wie z.B. neu aufkommende Krankheiten, schneller anzupassen. Der Haupthistocompatibilitätskomplex (MHC) ist eine Familie von Genen, der eine zentrale Rolle im Immunsystem von Wirbeltieren zukommt, da sie nach Pathogenkontakt das adaptive Immunsystem aktivieren. Zudem sind MHC Gene geeignete molekulare Marker um Anpassungsfähigkeiten aufzuzeigen. MHC Gene kodieren primär für Zelloberflächenmoleküle, die kurze Peptidfragmente erkennen und den Immunzellen präsentieren, die im Falle der Klasse I Gene intrazellulären (z.B. von Viren) oder im Falle der Klasse II Gene extrazellulären (z.B. von Bakterien, Protozoen, Arthropoden) Ursprungs sein können. In der Regel wird in natürlich vorkommenden Populationen ein hoher Grad an Polymorphismus im MHC beobachtet, was als Anpassung an das Erkennen und Präsentieren einer großen Anzahl sich schnell entwickelnder Pathogene interpretiert wird. Das Bestehen vieler MHC Varianten über große Zeiträume hinweg wird hauptsächlich durch positive Selektion bewirkt, der ein pathogengetriebener Selektionsdruck zugrunde liegt.
In meiner Doktorarbeit habe ich mich mit der Variation von MHC I and MHC II in freilebenden Geparden (Acinonyx jubatus) und Leoparden (Panthera pardus) in Farmgebieten innerhalb Namibias beschäftigt. Beide Felidenarten leben sympatrisch und sind so demselben Pathogendruck ausgesetzt, sie unterscheiden sich allerdings in ihrem evolutionären und demographischen Hintergrund. Mein Hauptziel war es 1) das Ausmaß und Muster der MHC Variation auf Populationsebene beider Feliden zu untersuchen; 2) einen möglichen Zusammenhang zwischen dem Grad der MHC Variation und der Krankheitsresistenz in frei lebenden Geparden aufzudecken und 3) zu untersuchen, welche Rolle der Selektion auf die MHC Variabilität beider Arten in der Vergangenheit wie auch gegenwärtig zukommt. Geparden und Leoparden repräsentieren die größten frei lebenden Carnivoren Namibias. Beide Arten kommen hauptsächlich in Farmgebieten vor, die sich in Privatbesitz befinden, und können dort mit anderen Wild- aber auch Haustieren zusammentreffen und potentiell Krankheitserreger austauschen. Die Kenntnis über die adaptive genetische Variation, die für Krankheitsresistenzen mitverantwortlich ist, kann für den Schutz beider Felidenarten von Bedeutung sein.
Geparden werden häufig in Lehrbüchern als klassische Beispiele für eine Tierart mit einer generell geringen genetischen Diversität verwendet. Neben neutralen Markern ist bei Geparden auch eine geringe Variabilität der MHC Gene beschrieben worden, die als Ursache einer hohen Anfälligkeit für infektiöse Krankheiten gesehen wird. Bisher wurde allerdings eine erhöhte Krankheitsanfälligkeit nur bei Geparden aus Gefangenschaft beschrieben, wohingegen neuste Studien an frei lebenden Geparden diesen einen guten Gesundheitsstatus attestierten. Dadurch stellt sich die Frage, ob die MHC I und II Diversität in frei lebenden Geparden nicht höher sein könnte als bisher angenommen. In dieser Arbeit konnten insgesamt 10 MHC I und vier MHC II Allele in 149 frei lebenden Geparden aus ganz Namibia nachgewiesen werden. Die Zugehörigkeit zu funktionellen MHC Genen wurde durch Expressionsanalysen bei allen Allelen, außer einem, bestätigt. Durch phylogenetische Analysen konnten die Allele vier MHC I und drei MHC II Genen zu geordnet werden. Das Wirken von positiver Selektion in der Vergangenheit konnte an spezifischen Aminosäuren des Proteins, die in direktem Kontakt zu den pathogenen Antigenen stehen, festgestellt werden. Dies traf für beide MHC Klassen zu. Des Weiteren konnte eine starke genetische Differenzierung des MHC I zwischen Geparden aus einer nord-zentralen und einer ost-zentralen Region festgestellt werden, von denen auch bekannt ist, dass sie unterschiedlichen, felidenspezifischen, viralen Pathogenen ausgesetzt sind. Das lässt vermuten, dass die unterschiedlichen Muster der MHC I Variation in der gegenwärtigen Population den unterschiedlichen pathogengetriebenen Selektionsdruck durch Viren in den beiden Regionen widerspiegelt. Verglichen mit anderen Säugetierarten, insbesondere andere Feliden, zeigen Geparden einen geringen Grad an MHC Diversität, doch das scheint die derzeitige Immunkompetenz frei lebender Geparden in Namibia nicht einzuschränken und widerspricht der bisherigen Meinung dass Geparden ein typisches Beispiel für eine krankheitsanfällige Tierart sind. Es kann allerdings nicht ausgeschlossen werden, dass bei neu auftauchenden Krankheiten die geringe MHC Variation eine erfolgreiche Immunkompetenz verhindert, da möglicherweise keines der gegenwärtigen Allele die Fähigkeit besitzt neue Pathogene zu erkennen.
Im Gegensatz zu Geparden kommen Leoparden in allen Teilen Afrikas vor und sind wahrscheinlich die am weitverbreiteste Großkatze des afrikanischen Kontinents. Es scheint, dass Leoparden, im Gegensatz zu anderen afrikanischen Großkatzen, einer ausgedehnten Dezimierung durch Tierseuchen in der Vergangenheit, der einige Populationen afrikanischer Großkatzen ausgesetzt waren, entkommen sind. Bisher fehlten Information über die MHC Variabilität in afrikanischen Leoparden. In dieser Studie konnte ich die genetische Variation der MHC I und MHC II Gene frei lebender namibischer Leoparden charakterisieren. In 25 Tieren aus einer Population der ost-zentralen Region konnten sechs MHC I sowie sechs MHC II Sequenzen nachgewiesen werden. Aus der maximalen Anzahl Allele pro Tier kann auf drei MHC I und auf drei MHC II Gene geschlossen werden. Außerdem konnten die typischen Kennzeichen einer variationserhaltenden MHC Evolution betätigt werden, wie positive Selektion in der Vergangenheit, Rekombination und über Artgrenzen hinaus bestehender Polymorphismus. Der geringe Grad an MHC Variation in namibischen Leoparden ist jedoch noch nicht endgültig und weitere Untersuchungen in unterschiedlichen Regionen aus der gesamten geographischen Verbreitung des Leoparden sind notwendig um die MHC Variation der Leoparden in Gänze einschätzen zu können.
Die Ergebnisse dieser Arbeit werden zu einem besseren Verständnis des evolutionären Stellenwerts des MHC und in Folge zu einem besseren Schutz von frei lebenden Feliden beitragen. Die Umsiedelung von Wildtieren ist ein zunehmend angewendetes Hilfsmittel im Natur- und Artenschutz, welches jedoch mit Sorgfalt eingesetzt werden sollte, da die umgesiedelten Tiere möglicherweise einem anderen pathogenen Selektionsdruck ausgesetzt sind, dem sie nichts entgegenzusetzen haben.
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Aspects of the reproductive biology of the South African leopard (Panthera pardus)Szamosvari, Jamie-Lee January 2014 (has links)
M.Sc. (Zoology) / The reproductive biology of the South African leopard, Panthera pardus has not been studied in detail. In South Africa little is known about the population numbers of leopards due to their solitary and nocturnal nature and currently the conservation and management of leopard populations relies mainly on the contributions of non-governmental organisations, academic institutions and private individuals. The aim of this study was to provide baseline information for the development of in-situ and ex-situ reproductive conservation methods for the leopard. In order to meet this aim, the following objectives were established: 1) determine the degree of relatedness of the leopards sampled, 2) establish baseline parameter values of a whole blood count and describe the ultrastructure of the blood cells, 3) obtain semen by means of electroejaculation and determine the efficiency of a previously described cryopreservation protocol for leopard spermatozoa, 4) describe the morphology and ultrastructure of the leopard spermatozoa using florescence and electron microscopy, 5) describe the histology and ultrastructure of the leopard testes and the events of spermatogenesis using light and electron microscopy. Between January 2011 and February 2013, blood and semen samples were obtained from eleven leopards after being sedated with a combination of Medetomidine and Ketamine. The DNA was extracted from the blood (ARC Genetics Department) and analysed (Onderstepoort Veterinary Genetics Laboratory). The blood was also used for the analysis of the baseline blood parameter values (Lancet Laboratories). Whole blood was fixed in 2.5% phosphate buffered gluteraldehyde and prepared for transmission and scanning electron microscopy to describe the ultrastructure of the cells. Techniques to examine sperm morphology included florescence and electron xviii microscopy. The semen was fixed in 2.5% gluteraldehyde and phosphate buffer for the ultrastructural assessment. Testes samples obtained from a leopard that died during transportation were fixed in Bouin’s fixative and a phosphate buffered 2.5% gluteraldehyde solution for light and electron microscopy respectively. The testes samples were prepared using standard techniques and stained with Hemotoxylin and Eosin for light microscopy and uranyl acetate and lead citrate for electron microscopy. The DNA analysis revealed that two pairs of leopards were related on a half-sibling level. The mean parameter values of the whole blood count of P. pardus were similar to the values recorded for Asian leopards, P. pardus African lions, Panthera leo and bobcats, Lynx rufus and fell within the normal ranges for the domestic cat, Felis catus. The ultrastructural assessment of the blood cells was comparable with those that have been described for the Asian leopard as well as most other mammalian species. A small volume of semen (≤0.5 ml) could be obtained from five out of nine male leopards that were sampled. The morphology and ultrastructure of the leopard spermatozoa conforms to the generalised structure of spermatozoa of most mammalian species. A large number of morphologically abnormal spermatozoa were noted. This has also been reported for many feline species, including the Indian leopards. Spermatozoa abnormalities identified included coiled tails, cytoplasmic droplets and knobbed acrosomes. The cryopreservation of the spermatozoa yielded a maximum post-thaw progressive motility of 24.4%. The histology and ultrastructural events of spermatogenesis in the leopard testes were compared to that of the domestic cat and some differences were observed between the domestic cat testes and leopard testes. The results of this study provide baseline information on the genetic diversity and reproductive biology of the leopards in South Africa. This can be used in the development of assisted reproductive techniques that may one day aid in conservation strategies for the leopards.
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Viability of leopards Panthera pardus (Linnaeus, 1758) in South AfricaSwanepoel, Lourens Hendrik January 2013 (has links)
Leopards Panthera pardus are highly adaptable large felids that persist in un-protected areas throughout South Africa. However, leopards are frequently involved in conflict with land users and subsequently killed in retaliatory incidents. Efforts to foster tolerance for leopard conservation largely rely on trophy hunting and ecotourism. However there is growing concern that trophy hunting may lead to population declines. Combining this with shortages of demographic data generates serious conservation challenges for wildlife managers. In this thesis, I evaluated the viability of the South African leopard population using simulation models and empirically collected data. I further evaluated the response of people engaged in retaliatory killing of leopards and leopard trophy hunters to varying leopard abundance. A habitat suitability model suggested that current suitable leopard habitat is fragmented and that the majority exists on non-protected areas. The national protected area system was largely ineffective in capturing suitable leopard habitat. Stochastic population models suggested unsustainable harvest levels at the current levels of retaliatory killing. Furthermore, simulations with only non-harvest related anthropogenic mortality also produced high probabilities of decline, indicating that non-harvest related anthropogenic mortality, such as retaliatory killings, can significantly impact the sustainability of harvest and the viability of the South African leopard population. Likewise survival analysis indicated that leopard survival in non-protected areas was significantly lower than in protected areas, and that humans were responsible for the majority of leopard deaths in non-protected areas. Finally retaliatory killing occurred at a higher rate of killing at low leopard abundances compared to hunting. Therefore retaliatory killing of leopards are more likely to be detrimental to leopard populations than trophy hunting. My findings strongly suggest that non-protected areas are important for leopard conservation, but that conflict in these areas currently may limit their conservation potential. I therefore suggest that the control of retaliatory killing of leopards may be more effective in promoting leopard persistence than restricting trophy harvest. Furthermore, conservation actions that aim to foster increased participation by the private sector, representing non-protected areas, in large carnivore conservation initiatives may be particularly beneficial to the long term conservation of leopards. / Thesis (PhD)--University of Pretoria, 2013. / gm2013 / Animal and Wildlife Sciences / restricted
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The conservation biology of the leopard (Panthera pardus)in Gabon / Status, threats and strategies for conservation / Der Schutzstatus des Leoparden (Panthera pardus) in Gabun / Bestände, Gefährdungen und Strategien zum SchutzHenschel, Philipp 21 January 2009 (has links)
No description available.
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The ecology of the leopard (Panthera Pardus) in the WaterbergGrimbeek, Anton Michael 17 November 2005 (has links)
Although the opportunistic feeding habits of leopards were evident in this study, scat analysis showed that ungulates were by far the predominant food, with impala being the most frequent item. The fact that cattle calves were only taken up to ± 100 days old, emphasize the relevance of a proper stock management program to prevent stock losses. In addition, where such measures were impractical, temporary physical barriers such as electric fencing showed potential for application. Modification on different capture techniques were investigated not only to capture leopards for radio collaring but also for the elimination of problem leopards. The effective home range size of a resident male and female leopard in the Naboomspruit area were calculated at 303 km2 and 157 km2 respectively. A density of one leopard per 53 km2 are suggested for the Naboosmpruit study area. Both leopards were predominantly nocturnal with some crepuscular activity. Translocation experiments revealed different results. The conducting of translocations in farming areas, where problem leopards are involved are however not suggested. Leopard density and distribution patterns showed that numbers are relative safe, and that populations are currently to a large extent linked, which makes natural gene flow a possibility. Although suitable areas for leopards thus exist, these may not be available as homogenous units in the future, due to increasing human pressure. / Dissertation (MSc (Zoology))--University of Pretoria, 2006. / Zoology and Entomology / unrestricted
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Prey preferences of the Persian leopard and trophic competition with human hunters in IranGhoddousi, Arash 24 August 2016 (has links)
No description available.
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Ecology of Tigers in Churia Habitat and a Non-Invasive Genetic Approach to Tiger Conservation in Terai Arc, NepalThapa, Kanchan 13 October 2014 (has links)
Tigers (Panthera tigris tigris) can be viewed as a proxy for intact and healthy ecosystems. Their wild populations have plummeted to fewer than 3,200 individuals in the last four decades and threats to these apex predators are mounting rather than diminishing. Global conservation bodies (Global Tiger Initiative, World Wildlife Fund, Wildlife Conservation Society, Panthera etc.) have recently called for solidarity and scaling up of conservation efforts to save tigers from extinction.
In South Asia, tiger habitat ranges from tropical evergreen forests, dry arid regions and sub-tropical alluvial floodplains, to temperate mixed deciduous forest. The churia habitat is relatively unstudied and is considered a young and geologically fragile mountain range in Nepal. The contribution of the churia habitat to tiger conservation has not been considered, since modern conservation started in 1970's. This study focuses on the ecology of the tiger with respect to population density, habitat use, and prey occupancy and density, in the churia habitat of Chitwan National Park. This study also includes the first assessment of genetic diversity, genetic structure, and gene flow of tigers across the Terai Arc Landscape- Nepal. The Terai Arc Landscape harbors the only remaining tiger population found across the foothills of the Himalayas in Nepal and northwest India. I used a combination of camera-trapping techniques, which have been a popular and robust method for monitoring tiger populations across the landscape, combined with a noninvasive genetic approach to gain information on tigers, thus adding new information relevant to global tiger conservation.
I investigated tiger, leopard (Panthera pardus fusca), and prey densities, and predicted the tiger density across the Churia habitat in Chitwan National Park. I used a camera-trap grid with 161 locations accumulating 2,097 trap-nights in a 60 day survey period during the winter season of 2010-2011. Additionally, I used distance sampling techniques for estimating prey density in the churia habitat by walking 136 km over 81 different line transects. The team photographed 31 individual tigers and 28 individual leopards along with 25 mammalian species from a sampling area of 536 km² comprising Churia and surrounding areas. Density estimates of tigers and leopards were 2.2 (SE 0.42) tigers and 4.0 (SE 1.00) leopards per 100 km². Prey density was estimated at 62.7 prey animals per 100 km² with contributions from forest ungulates to be 47% (sambar Rusa unicolor, chital Axis axis, barking deer Muntiacus muntjak, and wild pigs Sus scrofa). Churia habitat within Chitwan National Park is capable of supporting 5.86 tigers per 100 km² based on applying models developed to predict tiger density from prey density. My density estimates from camera-traps are lower than that predicted based on prey availability, which indicates that the tiger population may be below the carrying capacity. Nonetheless, the churia habitat supports 9 to 36 tigers, increasing estimates of current population size in Chitwan National Park. Based on my finding, the Churia habitat should no longer remain ignored because it has great potential to harbor tigers. Conservation efforts should focus on reducing human disturbance to boost prey populations to potentially support higher predator numbers in Churia.
I used sign surveys within a rigorous occupancy framework to estimate probability of occupancy for 5 focal prey species of the tiger (gaur Bos gaurus, sambar, chital, wild pig, and barking deer); as well as probability of tiger habitat use within 537 km² of churia habitat in Chitwan National Park. Multi-season, auto-correlation models allowed me to make seasonal (winter versus summer) inferences regarding changes in occupancy or habitat use based on covariates influencing occupancy and detection. Sambar had the greatest spatial distribution across both seasons, occupying 431-437 km² of the churia habitat, while chital had the lowest distribution, occupying only 100-158 km². The gaur population showed the most seasonal variation from 318- 413 km² of area occupied, with changes in occupancy suggesting their migration out of the lowland areas in the summer and into the churia in the winter. Wild pigs showed the opposite, moving into the churia in the summer (444 km² area occupied) and having lower occupancy in the winter (383 km²). Barking deer were widespread in both seasons (329 - 349 km²). Tiger probability of habitat use Ψ SE(Ψ) was only slightly higher in winter 0.63 (SE 0.11) than in summer 0.54 (SE 0.21), but confidence intervals overlapped and area used was very similar across seasons, from 337 - 291 km². Fine-scale variation in tiger habitat use showed that tigers intensively use certain areas more often than others across the seasons. The proportion of available habitat positively influenced occupancy for the majority of prey species and tigers. Human disturbance had a strong negative influence on the distribution of the majority of prey species but was positively related to tiger habitat use. Tigers appear to live in areas with high disturbance, thus increasing the risk of human-tiger conflict in the churia habitat. Thus, efforts to reduce human disturbance would be beneficial to reducing human wildlife conflict, enriching prey populations, and would potentially support more tigers in churia habitat of Nepal. Overall, I found high prey occupancy and tiger habitat use, suggesting that the churia is highly valuable habitat for tigers and should no longer be neglected or forgotten in tiger conservation planning.
Thirdly, I assessed genetic variation, genetic structure, and gene flow of the tigers in the Terai Arc Landscape, Nepal. I opportunistically collected 770 scat samples from 4 protected areas and 5 hypothesized corridors across the Terai Arc Landscape. Historical landuse change in the Terai Arc was extracted from Anthrome data sets to relate landuse change to potential barriers and subsequent hypothesized bottleneck events in the landscape. I used standard genetic metrics (allelic diversity and heterozygosity) to estimate genetic variation in the tiger population. Using program Structure (non-spatial) and TESS (spatial), I defined the putative genetic clusters present in the landscape. Migrant analysis was carried out in Geneclass and Bayesass for estimating contemporary gene flow. I tested for a recent population bottleneck with the heterozygosity test using program Bottleneck. Of the 700 samples, 396 were positive for tiger (57% success). Using an 8 multilocus microsatellite assay, I identified 78 individual tigers. I found large scale landuse changes across the Terai Arc Landscape due to conversion of forest into agriculture in last two centuries and I identified areas of suspected barriers. I found low levels of genetic variation (expected heterozygosity = 0.61) and moderate genetic differentiation (F<sub>ST</sub> = 0.14) across the landscape, indicative of sub-population structure and potential isolation of sub-populations. I detected three genetic clusters across the landscape consistent with three demographic tiger sub-populations occurring in Chitwan-Parsa, Bardia, and Suklaphanta protected areas. I detected 10 migrants across all study sites confirming there is still some dispersal mediated gene flow across the landscape. I found evidence of a bottleneck signature, especially around the lowland forests in the Terai, likely caused by large scale landuse change in last two centuries, which could explain the low levels of genetic variation detected at the sub-population level. These findings are highly relevant to tiger conservation indicating that efforts to protect source sites and to improve connectivity are needed to augment gene flow and genetic diversity across the landscape.
Finally, I compared the abundance and density of tigers obtained using two non-invasive sampling techniques: camera-trapping and fecal DNA sampling. For cameras: I pooled the 2009 camera-trap data from the core tiger population across the lowland areas of Chitwan National Park. I sampled 359 km² of the core area with 187 camera-trap locations spending 2,821 trap-nights of effort. I obtained 264 identifiable photographs and identified a total of 41 individual tigers. For genetics, I sampled 325 km² of the core area along three spatial routes, walking a total of 1,173 km, collecting a total of 420 tiger fecal samples in 2011. I identified 36 tigers using the assay of 8 multilocus genotypes and captured them 42 times. I analyzed both data types separately for estimating density and jointly in an integrated model using both traditional, and spatial, capture-recapture frameworks. Using Program MARK and the model averaged results, my abundance estimates were 46 (SE 1.86) and 44 (SE 9.83) individuals from camera and genetic data, respectively. Density estimates (tigers per 100 km²) via traditional buffer strip methods using half of the Mean Maximum Distance Moved (½ MMDM) as the buffer surrounding survey grids, were 4.01 (SE 0.64) for camera data and 3.49 (SE 1.04) for genetic data. Spatially explicit capture recapture models resulted in lower density estimates both in the likelihood based program DENSITY at 2.55 (SE 0.59) for camera-trap data and 2.57 (SE 0.88) for genetic data, while the Bayesian based program SPACECAP estimates were 2.44 (SE 0.30) for camera-trap data and 2.23 (SE 0.46) for genetic data. Using a spatially explicit, integrated model that combines data from both cameras and genetics, density estimates were 1.47 (SD 0.20) tigers per 100 km² for camera-trap data and 1.89 (SD 0.36) tigers per 100 km² for genetic data. I found that the addition of camera-trap data improved precision in genetic capture-recapture estimates, but not visa-versa, likely due to low numbers of recaptures in the genetic data. While a non-invasive genetic approach can be used as a stand-alone capture-recapture method, it may be necessary to increase sample size to obtain more recaptures. Camera-trap data may provide a more precise estimates, but genetic data returns more information on other aspect of genetic health and connectivity. Combining data sets in an integrated modeling framework, aiding in pinpointing strengths and weaknesses in data sets, thus ultimately improving modeling inference. / Ph. D.
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The impact of intraguild competition with lion (Panthera leo) on leopard (Panthera pardus) behavioural ecologydu Preez, Byron Dennis January 2014 (has links)
Single-species research dominates the field of ecology; however there is a growing appreciation of the importance of a multi-species approach to holistic conservation. Carnivores exert a top-down control on other species, and are vital components of stable ecosystem functioning. Physiologically adapted for predation upon other animals, competition between carnivores can be particularly aggressive; frequently resulting in mortality, and even population suppression. Big cat research has historically focused on those species that are most easily observable; in particular the lion Panthera leo. The majority of the Felidae however are secretive and elusive, and receive relatively little scientific attention. In particular, there are few data available that measure the effect of direct intraguild interactions between carnivores. Using leopards Panthera pardus as a model species, this research aimed to investigate the impact of lions on the behavioural ecology of a socially subordinate carnivore. Leopards are the most abundant large carnivore in Africa, and have the largest global range of all felids; their ecological niche overlapping with that of both lions and tigers. The knowledge gained from examining their competitive interactions is therefore widely relevant, and may be applicable to other subordinate carnivore species that remain unstudied. Biotelemetry and camera-trap data were modelled using novel algorithms to show that lions impact on leopard population density, demographics and spatial ecology. Faecal analyses suggest that dietary niche segregation may facilitate sympatry. These results indicate the level of impact that large carnivores can exert over smaller species, and the potential for a focus on single-species conservation to undermine holistic conservation. The manifestation of intraguild competition has a significant influence on an animal’s ecology; leopards are generalist species that cope with persecution by adapting their behaviour and niche. Ecological specialists may not fare as well under competitive pressure, and proactive conservation initiatives may be required for endangered species.
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