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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
331

On the ecology of invasive species, extinction, ecological history, and biodiversity conservation

Donlan, Charles Joseph. January 2008 (has links) (PDF)
Thesis (Ph. D.)--Cornell University, 2008. / Title from PDF t.p. (viewed on Apr. 20, 2009). Vita. Includes bibliographical references. Mode of access: World Wide Web.
332

Implementation of regional plans in the Pacific Northwest : an analysis of the Northwest Power Planning Council's water budget and model conservation standards 1984-1993 /

Mullens, Jo Beth, January 1900 (has links)
Thesis (Ph. D.)--Oregon State University, 1995. / Typescript (photocopy). Includes bibliographical references (leaves 237-252). Also available online.
333

An assessment of perceived crop damage in a Tanzanian village impacted by human-elephant conflict and an investigation of deterrent properties of African elephant (Loxodonta africana) exudates using bioassays

Karimi, Rebekah R. Schulte, Bruce A. January 2009 (has links) (PDF)
"A thesis submitted to the Graduate Faculty of Georgia Southern University in partial fulfillment of the requirements for the degree Master of Science." Title from PDF of title page (Georgia Southern University, viewed on June 19, 2010). Bruce A. Schulte, major professor; Lissa M. Leege, J. Michelle Cawthorn, committee members. Electronic version approved: December 2009. Includes bibliographical references (p.76-78).
334

Utilising the human dimensions of wildlife management approach to initiate an understanding of the ways in which New Zealanders value wildlife in Aotearoa, New Zealand /

Cowie, Sarah. January 2006 (has links)
Thesis (B.Soc.Sc.(Hons.))--University of Waikato, 2006. / Includes bibliographical references (leaves 132-140) Also available via the World Wide Web.
335

A stepwise approach to understanding and effectively mitigating human-wildlife interactions

Rodríguez, Rocío A. Pozo January 2017 (has links)
The study of conflicts in conservation (also known as human-wildlife conflicts) is a growing field of research in areas where people and wildlife interact, because of the negative impacts each can have on the other. Addressing conflicts is certainly challenging because of the complexities of considering diverse interests from numerous stakeholders and the specific ecological and socio-economic characteristics of a given study system. No matter how complex the system under study is, the aim is in all cases to find effective and sustainable mitigation strategies for local people, as well as for wildlife conservation and local authorities. In this thesis, I look at two of the preliminary steps required to address conservation conflicts and develop efficient long-lasting management solutions: the gathering of ecological data and the assessment of mitigation strategies in the field. To do this, I use two case studies: crop-foraging by African elephants (Loxodonta africana) in northern Botswana, and selective hunting of the red deer (Cervus elaphus) population on the Isle of Rum in Scotland. In Chapter 2, I built a baseline for the level of conflict in the Okavango Delta Panhandle (Botswana) using temporal trends of crop-foraging by elephants as an index of the level of conflict, and subsequently looked at how this relates to trends in agricultural land allocated in the study area, as well as with trends in human and elephant population size. In Chapter 3, I mapped the distribution of the local population of elephants and assessed its interaction with landscape features and sites where crop-foraging events had been recorded. In both chapters (2 & 3) I found that -in general- the number of elephants was not a determinant of the level of conflict in the study area, but that the spatiotemporal distribution of the species as well as the spatial and temporal scales considered were. In the second half of my thesis, I assessed the effects of two common conflict mitigation methods: the use of deterrents (Chapter 4) and lethal control (Chapter 5). I first evaluated the effectiveness of chilli-briquettes in deterring elephants and secondly, I used a modelling approach to predict the demographic effects of increasing levels of selective hunting in a male red deer population. I found that both mitigation methods showed unexpected results, which would not have been detected had I not tested for them. This thesis highlights the advantages of applying methods that are based on informed decisions in areas of conflict, as well as the value of sharing results in conservation management. My findings contribute towards a better understanding of the negative impacts of human-wildlife interactions, which often lead to conservation conflicts, as well as contributing protocols and methodologies that can be adapted and applied elsewhere.
336

Herpetofauna and Riparian Microhabitat of Urban and Wildland Reaches Along the Salt River, Arizona

January 2011 (has links)
abstract: Worldwide, riverine floodplains are among the most endangered landscapes. In response to anthropogenic impacts, riverine restoration projects are considerably increasing. However, there is a paucity of information on how riparian rehabilitation activities impact non-avian wildlife communities. I evaluated herpetofauna abundance, species richness, diversity (i.e., Shannon and Simpson indices), species-specific responses, and riparian microhabitat characteristics along three reaches (i.e., wildland, urban rehabilitated, and urban disturbed) of the Salt River, Arizona. The surrounding uplands of the two urbanized reaches were dominated by the built environment (i.e., Phoenix metropolitan area). I predicted that greater diversity of microhabitat and lower urbanization would promote herpetofauna abundance, richness, and diversity. In 2010, at each reach, I performed herpetofauna visual surveys five times along eight transects (n=24) spanning the riparian zone. I quantified twenty one microhabitat characteristics such as ground substrate, vegetative cover, woody debris, tree stem density, and plant species richness along each transect. Herpetofauna species richness was the greatest along the wildland reach, and the lowest along the urban disturbed reach. The wildland reach had the greatest diversity indices, and diversity indices of the two urban reaches were similar. Abundance of herpetofauna was approximately six times lower along the urban disturbed reach compared to the two other reaches, which had similar abundances. Principal Component Analysis (PCA) reduced microhabitat variables to five factors, and significant differences among reaches were detected. Vegetation structure complexity, vegetation species richness, as well as densities of Prosopis (mesquite), Salix (willow), Populus (cottonwood), and animal burrows had a positive correlation with at least one of the three herpetofauna community parameter quantified (i.e., herpetofauna abundance, species richness, and diversity indices), and had a positive correlation with at least one herpetofauna species. Overall, rehabilitation activities positively influenced herpetofauna abundance and species richness, whereas urbanization negatively influenced herpetofauna diversity indices. Based on herpetofauna/microhabitat correlations established, I developed recommendations regarding microhabitat features that should be created in order to promote herpetofauna when rehabilitating degraded riparian systems. Recommendations are to plant vegetation of different growth habit, provide woody debris, plant Populus, Salix, and Prosopis of various ages and sizes, and to promote small mammal abundance. / Dissertation/Thesis / M.S. Applied Biological Sciences 2011
337

Effects of Off-road Vehicles on Rodents in the Sonoran Desert

January 2012 (has links)
abstract: Human recreation on rangelands may negatively impact wildlife populations. Among those activities, off-road vehicle (ORV) recreation carries the potential for broad ecological consequences. A study was undertaken to assess the impacts of ORV on rodents in Arizona Uplands Sonoran Desert. Between the months of February and September 2010, rodents were trapped at 6 ORV and 6 non-ORV sites in Tonto National Forest, AZ. I hypothesized that rodent abundance and species richness are negatively affected by ORV use. Rodent abundances were estimated using capture-mark-recapture methodology. Species richness was not correlated with ORV use. Although abundance of Peromyscus eremicus and Neotoma albigula declined as ORV use increased, abundance of Dipodomys merriami increased. Abundance of Chaetodipus baileyi was not correlated with ORV use. Other factors measured were percent ground cover, percent shrub cover, and species-specific shrub cover percentages. Total shrub cover, Opuntia spp., and Parkinsonia microphylla each decreased as ORV use increased. Results suggest that ORV use negatively affects rodent habitats in Arizona Uplands Sonoran Desert, leading to declining abundance in some species. Management strategies should mitigate ORV related habitat destruction to protect vulnerable populations. / Dissertation/Thesis / M.S. Applied Biological Sciences 2012
338

Understanding wildlife distribution in the human-dominated landscape of Nepal:implications for conservation

PAUDEL, Prakash Kumar January 2012 (has links)
In this thesis, I have first reviewed biodiversity status and its conservation in Nepal, which indicates the need of linking the gaps between research and conservation of rare and endangered flora and fauna. Using three mountain ungulates as model species (barking deer - Muntiacus muntjak, Himalayan goral - Naemorhedus goral and Himalayan serow - Capricornis thar), I have investigated effects of human disturbances on wildlife distribution in the human-dominated landscapes of western Nepal, spanning from the subtropical Bardia National Park to the mountainous Shey Phoksundo National Park. I have developed habitat suitability maps for these three ungulate species and recommended a conservation priority area for their conservation. A special emphasis was placed on the study of the distribution of Himalayan serow using different factors related to habitat fragmentation, hunting and patch characteristics and connectivity of forest in midhills landscape of Nepal. Finally, wildlife hunting pattern in the region was investigated in order to explore wildlife conservation issues from the social perspective.
339

Flame Retardant Chemical Contamination of Seafood, Ecologically Sustainable Fisheries, and Significance for Biodiversity Conservation

January 2015 (has links)
abstract: Consumption of seafood poses a substantial threat to global biodiversity. Chemical contamination found in both wild-caught and farmed seafood also presents significant health risks to consumers. Flame retardants, used in textiles, upholstery, plastics, and other products to reduce risk of fire-related injury, are of particular concern as they are commonly found in the marine environment and permeate the tissues of fish that are sold for consumption via multiple pathways. The widespread issue of fishery collapse could be alleviated by demonstrating to stakeholders that many unsustainable fish stocks are also unhealthy and mutually disadvantageous for both human consumers and the environment. To thoroughly investigate the confounding factors and contradictory signals enmeshed in the relationship between ecologically sustainable fisheries and flame retardant contamination, I examined the biological characteristics of regional fish stocks which drive both contamination and perceived sustainability. I found that the biological and spatial aspects of commonly consumed aquatic and marine species best predict contamination when compared with various indices of sustainability. My results confirm that knowledge of flame retardant toxicity will become increasingly more important to consumers because a high percentage of global populations rely on coastal seafood for subsistence, and although dispersal of chemical contamination is still a poorly understood phenomenon, fish harvested closer to land are likely to contain higher concentrations of potentially harmful chemicals. Because some of the same biological traits which facilitate the uptake of chemicals also contribute to how a species responds to fishing pressures, concern for private health increases public consideration for the conservation of species at risk. / Dissertation/Thesis / Masters Thesis Biology 2015
340

Asian Great Bustards: From Conservation Biology to Sustainable Grassland Development

January 2015 (has links)
abstract: The Great Bustard (Otis tarda) is an iconic species of the temperate grasslands of Europe and Asia, a habitat that is among the least protected ecosystems in the world. A distinct subspecies, the Asian Great Bustard (O. t. dybowskii), is poorly understood due to its wary nature and remote range in Siberia, Mongolia, and northern China. This subspecies is now endangered by rapid development. Using satellite telemetry and remote sensing, I investigated three aspects of the Asian Great Bustard’s ecology critical to its conservation: migratory routes, migratory cues, and habitat use patterns. I found that Asian Great Bustards spent one-third of the year on a 2000 km migratory pathway, a distance twice as far as has previously been recorded for the species. Tracked individuals moved nomadically over large winter territories and did not repeat migratory stopovers, complicating conservation planning. Migratory timing was variable and migratory movements were significantly correlated with weather cues. Specifically, bustards migrated on days when wind support was favorable and temperature presaged warmer temperatures on the breeding grounds (spring) or advancing winter weather (fall). On the breeding grounds, Asian Great Bustards used both steppe and wheat agriculture habitat. All recorded reproductive attempts failed, regardless of habitat in which the nest was placed. Agricultural practices are likely to intensify in the coming decade, which would present further challenges to reproduction. The distinct migratory behavior and habitat use patterns of the Asian Great Bustard are likely adaptations to the climate and ecology of Inner Asia and underscore the importance of conserving these unique populations. My research indicates that conservation of the Asian Great Bustard will require a landscape-level approach. This approach should incorporate measures at the breeding grounds to raise reproductive success, alongside actions on the migratory pathway to ensure appropriate habitat and reduce adult mortality. To secure international cooperation, I proposed that an increased level of protection should be directed toward the Great Bustard under the Convention on Migratory Species (CMS). That proposal, accepted by the Eleventh Conference of Parties to CMS, provides recommendations for conservation action and illustrates the transdisciplinary approach I have taken in this research. / Dissertation/Thesis / Doctoral Dissertation Biology 2015

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