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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.
511

The Behavioral Ecology and Population Characteristics of Striped Skunks Inhabiting Piper Plover Nesting Beaches on the Island of Martha's Vineyard, Massachusetts

Johnson, Luanne, PhD 31 August 2016 (has links)
No description available.
512

Exploring complexities of fishery closures using octopus movements : an individual-based modelling approach

Berrío-Martínez, Jineth January 2022 (has links)
Temporary closures of octopus fishing areas constitute a promising co-management measure that aims to improve local governance, food security and incomes in coastal small-scale fishing communities. Although positive social and economic outcomes of temporary closures are increasingly reported, the underlying social-ecological and ecological interactions, and their impact on closure benefits are rarely studied. This lack of systemic understanding may lead to undesired outcomes. Here, I extend an existing agent-based model of temporary closures to explore the influence of individual octopus movements on ecological outcomes and fishers’ benefits in Zanzibar. First, I conceptualized the octopus closure system by analyzing empirical qualitative data and literature. Next, I iteratively developed and tested an individual-based model extension. This extension simulates between-den movements across a hypothetical seascape and formalizes intrinsic attributes of Octopus cyanea such as movement patterns and maturity stages. I analyzed the effects of varying closure size of fishing grounds temporarily closed to illustrate potential implications for outcomes of octopus closures. Simulation results show that individual octopus movements triggered by fishing activities have noticeable impacts on octopus sizes, their spatial and temporal distribution, and fishers’ catches, particularly when considering different social groups that depend on the fishery. Scenarios with closures in place show higher mean octopus weight in closed areas in contrast to open-access areas. Mean catches for women foot-fishers are lower compared to freedivers’ catches and even slightly lower when allowing octopuses to move in response to disturbance in all scenarios. Catch rates and distribution of mature octopuses are highly sensitive to closure size revealing a social-ecological trade-off when implementing larger closures. This study demonstrates an approach to integrating individual octopus movements and interactions between fishers and octopuses in a fishery management context, and suggests that reactive movement of octopus contributes to unequal distribution of the closure benefits between different social groups. / Octopus and People In Novel Transdisciplinary Simulations (OctoPINTS project)
513

Restorative urban design: toward a design method for mitigating human impacts on the natural environment through urban re/development

Toros, Tulu January 1900 (has links)
Doctor of Philosophy / Department of Environmental Design & Planning Program / Lee R. Skabelund / The Restorative Urban Design (RUD) calls for a new urban design and planning approach targeting environmentally responsible re/development of urbanized areas through ecologically responsive impact mitigations. If implemented in a systematic manner, such re/developments can help move urban areas toward the successful restoration of the natural environment of which they are an inseparable part. The RUD model advocates more rigorous assessment and mitigation of urban impacts by carefully evaluating the environmental performance of urban re/developments within five primary dimensions: Atmosphere (emissions, pollutants, ozone depletion); Hydrosphere (stormwater, domestic water, wastewater); Lithosphere (land use, land cover, food and wastes); Ecology (habitat resilience, biodiversity, population and resources); and Energy (renewability, reduction and efficiency, transportation). The model relies on a scenario-comparison process in order to evaluate and optimize the performance of urban re/development projections through four critical scenarios, which are respectively: 1) Natural Baseline (NBASE); 2) Historic Progression (HPROG); 3) Trajectory Forecast (TFORE); and 4) Restorative Projection (RPROJ). The RUD Case Study illustrates how the principles and strategies of Restorative Urban Design can be applied specifically to a typical (densely developed) urban area, namely River North District in Chicago Metropolitan Area. The case study focuses exclusively on mitigation of a single critical human impact on the natural environment: Anthropogenic CO₂ Emissions. The case study focuses on the design assumptions by which the restorative urban re/development scenarios might exceed beyond the full mitigation of emissions into the global remediation by 2040. The restorative projections illustrate that only a certain portion of emissions can be effectively mitigated onsite (5 to 55%), and that the remainder of projected emissions (45 to 95%) need to be mitigated offsite in order to achieve the necessary sequestration and storage. The restorative research suggests that the mitigation of major human impacts on the natural environment – not only CO₂ emissions but also other major impacts – are likely to require significant urban transformations. Moving beyond the strategies of preservation and/or conservation, the restorative approach asserts that comprehensive environmental restoration is achievable if urban impacts are adequately estimated and then entirely mitigated onsite as well as offsite through a systematic process of urban re/development.
514

Aspects of habitat selection, population dynamics, and breeding biology in the endangered Chatham Island oystercatcher (Haematopus chathamensis)

Schmechel, Frances A. January 2001 (has links)
In the late 1980s the endangered Chatham Island oystercatcher (Haematopus chathamensis) (CIO) was estimated at less than 110 individuals. Endemic to the Chatham Islands, New Zealand, it was feared to be declining and, based on existing productivity estimates, in danger of extinction within 50-70 years. These declines were thought to be caused by numerous changes since the arrival of humans, including the introduction of several terrestrial predators, the establishment of marram grass (Ammophila arenaria) which changes dune profiles, and increased disturbance along the coastline. The New Zealand Department of Conservation has undertaken recovery planning and conservation management to increase CIO numbers since the late 1980s. Recovery planning raised some key research questions concerning the population dynamics, habitat selection, and breeding biology of Chatham Island oystercatcher (CIO), and the critical factors currently limiting the population. The objectives of this study were to collect and interpret data on: 1) population size, trends, and distribution across the Chathams, 2) basic breeding parameters, 3) recruitment and mortality rates, 4) habitat selection at the general, territorial and nest-site levels, 5) habitat factors that are correlated with territory quality, and 6) cues that elicit territorial behaviour in CIO.
515

Understanding Participation in Wildlife Conservation Programs on Private Lands

Sorice, Michael G. 14 January 2010 (has links)
One major lesson derived from the implementation of the Endangered Species Act (ESA) over the past 30 years is that direct regulation is not the only nor the optimal way to protect endangered species on working lands because of an undue burden imposed on private landowners. The role of a voluntary conservation program is to rearrange incentives so that society bears the cost rather than the landowner. Employing a survey research methodology, I used theories of reasoned action and random choice to explore landowners? stated preferences for conservation programs. I found landowners? stated interest in compensation programs to be moderate at best. For those willing to consider programs involving endangered species, associating land management requirements for species conservation with direct benefits to the landowner is important, but perhaps not as important as ensuring that the program provides adequate financial incentives, consideration of the term of the program, and a level of certainty regarding the landowner?s future obligations under the ESA. Landowners are not a homogenous group. I identified two classes of landowners according to preferences for program structure. One group was highly sensitive to program structure, aside from financial incentives, while the other was likely to participate if adequately compensated with financial and technical assistance. These differences related to opinions on endangered species protection and dependence on their land for income. Voluntary incentive programs increasingly are a popular tool to maintain and enhance conservation; however, these programs are only successful insofar as landowners choose to enroll. This research demonstrates that improving recovery efforts on private lands requires program administrators to have a more complete understanding of landowners? views on endangered species and conservation programs in general, as well as their motivations for owning and operating their land. By doing so, programs with broader appeal and greater efficacy can be designed and implemented.
516

Feral cats (Felis catus) in an urban conservancy : University of KwaZulu- Natal, Howard College campus.

Tennent, Jaclyn Kim. January 2005 (has links)
The resident feral cat (Felis catus) population on the University of KwaZulu-Natal (UKZN), Howard College campus (HCC) in Durban, South Africa was studied from March 2004 to November 2005. This study was initiated as the HCC is an registered as an urban conservancy and so should be removing alien invasive flora and fauna and conserving the indigenous biodiversity of the campus. This research was undertaken to assist with recommendations for the control and management of feral cats on the HCe. A survey to determine public perceptions and opinions regarding the feral cats was conducted among various communities on the campus. Feral cats from the resident population on the HCC were trapped and fitted with radio-collars in order that their home range sizes and distribution could be determined. Monthly census counts were also carried out in an attempt to calculate population densities of the feral cats on campus, while data on behaviour patterns was collected opportunistically throughout the study period. The survey showed that two extreme views existed on campus regarding the presence of feral cats. The university is a registered conservancy which some feel is no place for this exotic species. However, it is also situated within an urban surrounding and there are some cat enthusiasts among the public who feel that resources should be provided for the feral cats, both nutritionally and financially. While many people were unaware that the feral cats were a cause for concern on the HCC, the majority concluded that a management policy needed to be adopted to control feral cat numbers. Most were against the suggestion of eradicating the cats and strongly agreed with the implementation of a university funded feral cat IV sterilising and feeding programme. Feeding the feral cats, however, needs to be stringently controlled. In this study, the availability of an abundance of food resources was shown to be the primary influencing factor for home range size, cat distribution and population densities. It also had an overriding effect on the feral cats' behaviour patterns and activity levels. Once these had been initially established, other factors such as human activity, reproductive status and gender then came into play. Distribution of the feral cats around campus was not homogenous, and densities differed according to areas on campus. Highest cat densities were recorded in those areas on the HCC where permanent cat feeding stations had been established (usually the developed areas on campus), while no feral cats were sighted in the Msinsi Nature Reserve, a natural bush area on campus were no food resources (other than prey species) is available. Home range sizes of the feral cats were relatively small with a considerable amount of overlap between and within the sexes. There were also no seasonal differences in range sizes and diurnal ranges were only marginally smaller than nocturnal range sIzes. In terms of behaviour, the HCC feral cats were generally inactive, with passive behaviour such as lying down and sitting being most often observed. Although hunting activity was very rarely witnessed, the combined effects of feral cats supported at high densities by supplemental feeding may exert predation pressures that could be detrimental to both local prey and predator populations. Little social interactions were observed by the cats on the HCC. Other studies show that competition is greatly reduced if food is available in abundance and there is no need for territorial disputes if both food and a potential mate are located in close proximity. In the present study, this also means that immigrating feral cats from surrounding neighbourhoods are tolerated; another factor contributing to the increase in feral cat numbers on the campus. These findings suggest that the feral cat population on the HCC is being maintained at higher population densities than would be expected and management initiatives are needed to control the feral cat population at a minimum density through a sterilising and low key feeding programme so that it is acceptable to all concerned parties. However, the decisions need to favour the status of the HCC as a conservancy in an urban area as well as consider the well-being of the students and staffmembers in a public place. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2005.
517

The implementation of an environmental monitoring and management system in the wilderness area of the Hluhluwe-Imfolozi Park.

Cryer, Paul Bernard. January 2009 (has links)
KwaZulu-Natal’s Hluhluwe-Imfolozi Park has historically been prioritized for biodiversity conservation but it also has the oldest protected wilderness area in the country. For 50 years, conservation management, tourism and education within the Imfolozi Wilderness Area have generally been carried out using non-mechanized wilderness principles. The validity of the Imfolozi Wilderness is constantly questioned in terms of efficiency, equity and aesthetics and is consequently subject to a variety of pressures that those different ideologies can exert. The historical development and applicability of the wilderness concept is examined here against evolving South African social and environmental circumstances. Whilst this investigation confirms the findings that colonialism and apartheid resulted in the exclusion of local peoples from protected areas, it also takes note that Imfolozi’s history is characterized by organizations and individuals who ignored the racist laws of the time. Nevertheless, management structures pertaining to both politics and conservation tended to be top-down, such that the Imfolozi Wilderness retained an air of elitism, regardless of attempts to be racially inclusive. Modern trends in protected area management expose the necessity of refining the justification of wilderness areas, to simultaneously recognize localized priorities and the importance of such areas to the planet’s ecological wellbeing. Without attempting to resolve philosophical debates but, at the same time, recognizing their validity, protected area management requirements for the Imfolozi Wilderness are examined in terms of the legal mandate handed to the management agency. This leads to the selection of the Limits of Acceptable Change planning and management system which is implemented as an action research project in conjunction with the Imfolozi Management Team, over a three year period. This involved: defining legal mandates and area issues; defining the zonation categories for the wilderness area; selecting the indicators to measure human impact; compiling an inventory of conditions in the wilderness area; specifying standards; examining alternative zonation category allocations from stakeholders and selecting a preferred alternative. The desired outcome was the establishment of a system in which managers could receive ongoing collaboration from stakeholders and consultatively develop a defendable wilderness management strategy that would meet the legal requirements of the area’s proclamation. Through a descriptive narrative, this dissertation provides an account of the implementation process and discusses to what extent this has been achieved. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2009.
518

Three Essays on Food Waste Management Planning

Arroyo-Rodriguez, Angel Santiago January 2020 (has links)
No description available.
519

Evaluating attitudes towards large carnivores within the Great Bear Rainforest

Leveridge, Max Carter 02 May 2019 (has links)
No description available.
520

Spider and Beetle Communities across Urban Greenspaces in Cleveland, Ohio: Distributions, Patterns, and Processes

Delgado de la flor, Yvan A. 11 September 2020 (has links)
No description available.

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