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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.
401

The taxonomy, ecology and conservation of Sousa chinensis (Osbeck, 1765) (Cetacea: Delphinidae) in Hong Kong waters

Porter, Lindsay Jane. January 1998 (has links)
published_or_final_version / Ecology and Biodiversity / Doctoral / Doctor of Philosophy
402

A Habitat Evaluation and Management Plan for a Riparian Ecosystem

Wilkinson, Robert N. 05 1900 (has links)
Ecological research involving habitat studies was conducted on the Elm Fork of the Trinity River in Denton County, Texas, from spring 1985 to spring 1986. Habitat Evaluation Procedures and Habitat Suitability Index Models developed by the United States Fish and Wildlife Service were applied to a 1419 hectares study area to determine the quality of habitat for four species: beaver, Castor canadensis, wood duck, Aix sponsa, pileated woodpecker, Dryocopus pileatus, and white crappie, Poxomis annularis. Population estimates were generated. A wildlife management plan was developed for the study area. Habitat Suitability Index Models were found to be overly conservative, underestimating the quality of habitat in areas of ecological transition.
403

Histories of Value: Following Deer Populations Through the English Landscape from 1800 to the Present Day

Marriott Webb, Holly January 2019 (has links)
Imagining the English landscape as an assemblage entangling deer and people throughout history, this thesis explores how changes in deer population connect to the ways deer have been valued from 1800 to the present day. Its methods are mixed, its sources are conversations – human voices in the ongoing historical negotiations of the multispecies body politic, the moot of people, animals, plants and things which shapes and orders the landscape assemblage. These conversations include interviews with people whose lives revolve around deer, correspondence with the organisations that hold sway over deer lives, analysis of modern media discourse around deer issues and exchanges with the history books. It finds that a non-linear increase in deer populations over the time period has been accompanied by multiple changes in the way deer are valued as part of the English landscape. Ending with a reflection on how this history of value fits in to wider debates about the proper representation of animals, the nature of non-human agency, and trajectories of the Anthropocene, this thesis seeks to open up new ways of exploring questions about human-animal relationships in environmental history.
404

Tolerance towards wildlife in the Atlantic forest: an empirical test across ecological contexts and mammal specie / Tolerância à fauna silvestre na Mata Atlântica: um teste empí­rico em diferentes contextos ecológicos e espécies de mamíferos

Teixeira, Lucas Manuel Cabral 03 July 2018 (has links)
Human-wildlife conflicts (HWC) emerge as complex conservation challenges impairing human livelihood and wildlife populations. Research on HWC, however, has traditionally approached these components apart and focused on single/ similar species, hampering a broader understanding of the connections between ecological drivers and human dimensions of conflicts. We here develop and test a model integrating ecological and human components of HWC, focusing on three species - opossum, crab-eating fox and puma. We investigated the pathways through which the ecological context (forest cover) affects experiences with wildlife (contact and damage), and how such experiences influence tolerance via beliefs, emotions and attitude. We interviewed 114 landowners across 13 landscapes varying in forest cover in a region of the Brazilian Atlantic forest and tested our model using Piecewise Structural Equation Modeling. We found that: i. forest cover negatively affected tolerance, but just towards the largest species; ii. relevance and effects of distinct experiences with wildlife on beliefs and emotions varied across species; iii. beliefs and emotions influenced tolerance, but negative emotions were relevant only for the largest species. Conflicts with larger species can then be understood as disservices provided by forests, indicating the relevance of framing HWC within a broader perspective that consider the trade-offs with ecosystems services. For some species, positive experiences with wildlife may counteract the negative effects of damages to livestock in shaping human behavior. Models such as ours - that structure relationships between ecological and human components - can help identifying deeper, more effective leverage points to improve interventions to mitigate HWC / Conflitos entre seres humanos e fauna silvestre emergem como desafios complexos, ameaçando o sustento de populações humanas e a conservação de populações de animais silvestres. Contudo, pesquisas sobre conflitos tradicionalmente abordam esses componentes separadamente e focam em espécies individuais ou similares, dificultando o entendimento mais amplo das conexões entre determinantes ecológicos e dimensões humanas dos conflitos. Neste estudo, desenvolvemos e testamos um modelo conceitual integrando componentes ecológicos e humanos dos conflitos, focando em três espécies - gambá, cachorro-do-mato e onça-parda. Investigamos os caminhos através dos quais o contexto ecológico (cobertura florestal) afeta experiências (contato e dano), e como tais experiências influenciam a tolerância à fauna por meio de crenças, emoções e atitude. Entrevistamos 114 proprietários rurais em 13 paisagens com diferentes proporções de cobertura florestal em uma região da Mata Atlântica e testamos nosso modelo usando equações estruturais do tipo Piecewise. Encontramos que: i. a cobertura florestal afetou negativamente a tolerância, mas apenas para a maior espécie; ii. a importância e os efeitos de diferentes experiências com a fauna sobre crenças e emoções variaram entre as espécies; iii. crenças e emoções influenciaram a tolerância, mas emoções negativas foram relevantes apenas para a maior espécie. Conflitos com espécies maiores podem então ser entendidos como desserviços providos por florestas, indicando a relevância de inserir os conflitos humano-fauna em perspectiva mais ampla, que considere as relações com serviços ecossistêmicos. Para algumas espécies, experiências positivas podem compensar os efeitos negativos dos danos a criações na formação do comportamento humano. Modelos como o nosso - que estruturem as relações entre os componentes ecológicos e humanos - podem ajudar a identificar pontos de alavancagem mais profundos e efetivos para melhorar intervenções visando a mitigação dos conflitos com a fauna
405

Contested spaces: NTFPS, livelihoods, and conservation planning

Unknown Date (has links)
This research examines tensions between Latino/a farmworkers, who rely on the seasonal harvest of saw palmetto (Serenoa repens [W. Bartram] Small) berries for increased livelihood security, and conservationists and land-managers who view harvesting as detrimental for wildlife. Informal harvesting occurs on public and private lands, sometimes without permission. Berries, though ubiquitous on the landscape, have become a contested resource. The rapid conversion of rural wildlife habitat into suburban development has increased State urgency to bring natural areas into protection along the Florida Ecological Greenways Network. Habitat infringement and associated pressures on wildlife by development has led to the promotion of the state-wide Florida Wildlife Corridor, based on the FEGN. This corridor would connect isolated Florida black bear (Ursus americanus floridanus) populations and Florida panthers (Puma concolor coryi) with other populations. The scale of the commercial berry industry is unknown, but is estimated at millions of pounds annually. State and wildlife conservationists are increasingly concerned with the perceived scale of the harvest and its possible associated effects on wildlife, particularly Florida black bears. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection
406

Deer-Vehicle Accident Hotspots in Northwest Clackamas County, Oregon

Anderson, Linda K. 01 January 2006 (has links)
Road-kill of wildlife is common on Portland, Oregon's suburban fringe where development has increased road densities and traffic volume in rural areas. I identify the spatial and temporal patterns of black-tailed deer (Odocoileus hemionus columbianus) deer-vehicle accidents (DVA) at the suburban/rural interface of developing northwest Clackamas County using deer carcass pickup reports for county maintained roads for 1997-2004 and Oregon Department of Transportation deer-vehicle accident reports for 1996-2004. No black-tailed deer DVA models exist in the literature. DVA increased 121% from 1997 to 1999 followed by a 26% decline by 2004. The initial DVA increase appears related to population growth and development into rural areas, an increase in the average daily vehicle-trip distance, and deer immigration from public lands. The subsequent decline appears related to DVA-induced decreases in deer populations, year-around hunting permits, growing predator populations, and fawning habitat loss. Temporal OVA patterns for black-tailed deer show a minor peak in June-July and a major peak in October-November. Forty-two percent of DVA occur during the rut/hunt months of September, October, and November. This pattern corresponds to the black-tail's annual cycle and resembles patterns reported for white-tailed deer (Odocoileus virginianus) and mule deer (Odocoileus hemionus columbianus). Weekly DVA increased from a low on Sunday to a high on Friday and Saturday. DVA showed two daily peaks at 0500-0700 and 1800-2200, corresponding to dawn and dusk when deer activity is highest. I identified 19 DVA hotspots with 16-27 DVA using CrimeStat III statistical clustering software. Hotspots occurring in rut/hunt months were separate from hotspots occurring in nonrut/nonhunt months. Similar to white-tailed and mule deer, black-tailed DVA hotspots commonly occurred where roads intersect or parallel water features, large forest blocks, and other areas of cover, or separate food sources from cover. Sixty-five percent of DVA occurred outside of hotspots with ≥ 10 DVA. Deer-vehicle accidents have important ecological and economic costs and are frequent on northwest Clackamas County roads. Additional research supported by multi-agency carcass pickup repo1ting and the acquisition of precise DV A locations using a Global Positioning System (GPS) is needed to better identify wildlife movement corridors.
407

The Status of Snapping Turtles (Chelydra serpentina) in Virginia: Population Viability, Demography, Regulatory Analysis, and Conservation

Colteaux, Benjamin C. 01 January 2017 (has links)
Snapping turtles (Chelydra serpentina) are being harvested in unprecedented numbers in the United States (US) to meet the needs of international markets. Over three million live snapping turtles from farm and wild caught stock were exported from the US to Asia in 2012-14 alone. In the Commonwealth of Virginia, records indicate that 29,860 snapping turtles were commercially harvested between 2000 and 2015. Size limits are often used to regulate harvest pressure in snapping turtles and other game species. I analyzed the historic harvest of eleven US states to test the efficacy of minimum-size limit regulations at reducing commercial harvest pressure. Further, I conducted a four-year mark-recapture study on three Virginia waterways that have each experienced a different level of historic commercial harvest. As part of the larger mark/recapture project, I conducted radio telemetry on 23 turtles to examine seasonal, body size, and sex-specific effects on home range size of snapping turtles in a lotic system. I incorporated survival and growth rates from this study, demographic rates from the literature, and state-collected harvest rates into a hybrid age/stage population matrix model to estimate the population growth rate at three harvest levels (0%, 21%, 58%) that were estimated based on annual commercial landing reports on file with the Virginia Department of Game and Inland Fisheries. I used the model to test population viability under multiple size limit regulations, and used sensitivity analyses to identify adult stages most critical to the overall population growth rate. Based on model estimates, size-limits were effective at reducing harvest by 30-87% in years with high harvest pressure. However, most size limit regulations result in the removal of larger breeding adults, which has been shown to be detrimental to long term population viability. Based on radio-telemetry data, I found evidence that snapping turtles utilize lotic and lentic habitats differently, which can have implications for management of this iconic species. Matrix population modelling predicted that population densities at the moderate and high harvest site were reduced by 47% and 62%, respectively, when compared to the no harvest site. Model results indicate that, while an increase to the minimum-size limit in 2012 protected a larger portion of the population, that the commercial harvest of snapping turtles in the Commonwealth of Virginia is not sustainable under current state regulations. Our analysis suggests that minimum-size limits of 35.6 cm curved carapace length or greater will maintain viable populations by protecting a larger portion of reproducing snapping turtles within a population.
408

Can urban greenways provide high quality avian habitat?

Hull, Jamie Rebekah, January 2003 (has links)
Thesis (M.S.)--North Carolina State University, 2003. / Title from PDF title page (viewed on Mar. 26, 2005). Includes vita. Includes bibliographical references.
409

Choice of social environment of male buffalo (syncerus caffer) in the Kruger National Park, South Africa.

Hay, Craig Thomson January 2007 (has links)
Thesis (MTech. degree in Nature Conservation ) - Tshwane University of Technology, 2007. / The tendency for male and female buffaloes to live separately outside the breeding season is termed sexual segregation. A number of hypotheses have being proposed to explain this behavior. This study, in an area with an intact predator community, strongly support the predation-risk hypothesis and attempts to clarify the function of sexual segregation in buffalo in southern Africa. It also contributes to understanding the possible consequences of selective removal of males for hunting or culling purposes.
410

Census techniques for southern reedbuck redunca arundinum on forestry lands in the Drakensberg/Natal Midlands. Component A, Literature review.

Boyes, R. S. January 2003 (has links)
No abstract available. / Thesis (M.Env.Dev.)-University of Natal, Pietermaritzburg, 2003.

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