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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.
161

Distributions of large mammal assemblages in Thailand with a focus on dhole (Cuon alpinus) conservation

Jenks, Kate E 01 January 2012 (has links)
Biodiversity monitoring and predictions of species occurrence are essential to develop outcome-oriented conservation management plans for endangered species and assess their success over time. To assess distribution and patterns of habitat use of large mammal assemblages in Thailand, with a focus on the endangered dhole (Cuon alpinus), I first implemented a long-term camera-trapping project carried out with park rangers from October 2003 through October 2007 in Khao Yai National Park. This project was extremely successful and may serve as a regional model for wildlife conservation. I found significantly lower relative abundance indices for carnivore species, and collectively for all mammals compared to data obtained in 1999–2000, suggesting population declines resulting from increased human activity. I integrated this data into maximum entropy modeling (Maxent) to further evaluate whether ranger stations reduced poaching activity and increased wildlife diversity and abundances. I then conducted a focused camera trap survey from January 2008 through February 2010 in Khao Ang Rue Nai Wildlife Sanctuary to gather critical baseline information on dholes, one of the predator species that seemed to have declined over time and that is exposed to continued pressure from humans. Additionally, I led a collaborative effort with other colleagues in the field to collate and integrate camera trap data from 15 protected areas to build a country-wide habitat suitability map for dholes, other predators, and their major prey species. The predicted presence probability for sambar (Rusa unicolor) and leopards (Panthera pardus) were the most important variables in predicting dhole presence countrywide. Based on my experience from these different field ecological surveys and endeavors, it became clear that local people's beliefs may have a strong influence on dhole management and conservation. Thus, I conducted villager interview surveys to identify local attitudes towards dholes, document the status of dholes in wildlife sanctuaries adjacent to Cambodia, and determine the best approach to improve local support for dhole conservation before proceeding with further field studies of the species in Thailand. A photograph of a dhole was correctly identified by only 20% of the respondents. My studies provide evidence that some protected areas in Thailand continue to support a diversity of carnivore speices of conservation concern, including clouded leopards (Neofelis nebulosa), dholes, and small felids. However, dholes' impact on prey populations may be increasing as tiger (Panthera tigris) and leopards are extripated from protected areas. The next step in dhole conservation is to estimate the size and stability of their fragmented populations and also focus on maintaining adequate prey bases that would support both large felids and dholes.
162

Population and spatial ecology of tigers and leopards relative to prey availability and human activity in thung yai naresuan (east) wildlife sanctuary, Thailand

Vinitpornsawan, Supagit 01 January 2013 (has links)
The Thung Yai Naresuan (East) Wildlife sanctuary (TYNE) is clarified as the Tiger Conservation Landscape of Global Priority and also a stronghold for other endangered and threaten species. Although, UNESCO designated this area, the cores of the Western Forest Complex (WEFCOM), as a Natural World Heritage Site in 1991, this wildlife has been threatened by habitat alteration, prey depletion, and direct killing. Yet, the information on impact of human activities and wildlife status that is needed to guild forest authorities to develop conservation strategies remains challenging. The goal of this dissertation was to increase understanding of tiger, other main predators, prey status, and also impact of human activities in the sanctuary. In the TYNE, the globally endangered species were observed including Asiatic Elephant (Elephas maximus), Tiger (Panthera tigris), Malayan Tapir (Tapirus indicus), Dhole (Cuon alpines), and Malayan Pangolin (Manis javanica). Spatially explicit capture-recapture approach estimated tiger density at 1.4-1.6 tigers/100 km2 and leopard density at 0.7-0.8 leopards/100 km2, which indicates that there might be 27±10 tigers (95% CL range from 11-46) and around 12±4 leopards (95% CL range from 8-19) roaming in the area around 1,596 km2 in TYNE. The large predators like tigers, leopards, and dholes co-occurred in the area with the combination of both spatial and temporal partitioning due to differences in predator and prey activity and low overlap in space use correlated to their prey preferences. Prey availability, human settlement areas, and human disturbance activities are the key limiting factors for their distribution and space-use. The habitat use of tiger and leopard demonstrated that the population distribution was limited in the central to the eastern part of the TYNE, while the local people occupied the west with high disturbance activities. The activities by local people in TYNE were varied and the impacts of the disturbance were complex. Slash and burn, livestock, tree cutting, and poaching appeared to be the major influence wildlife abundance and habitat around the settlement areas. The results of this study stress the need for the further conservation and management to maintain wildlife distribution and populations in the future. Better scientific understanding of wildlife biology, ecology, and social sciences would help to deal with the conservation and management issues facing the local communities and natural resources in Thung Yai Naresuan (East) Wildlife Sanctuary.
163

Community perceptions and attitudes towards integrated wildlife/livestock land-uses : the case of Greater-Giyani rural communities, Limpopo, Province

Baloi, Votumi Arone January 2016 (has links)
Thesis (M. Sc. (Agricultural Economics)) -- University of Limpopo, 2016 / Livestock production in communal areas is faced by a myriad of challenges such as environmental degradation, poor markets, stock theft and disease. This has drawn interest towards wildlife-based land-use practices as an alternative or complement to livestock production. Wildlife-based land-uses have potential to generate incomes and create employment in wildlife rich areas. On the other hand, several problems such as human-wildlife conflict have been identified in wildlife rich areas. This study investigated perceptions of rural households in areas adjacent to the Kruger National Park (KNP) regarding integrated wildlife/livestock land-use practices. Data were collected from 130 households in nine villages alongside KNP in Giyani. Respondents were stratified into cattle owning households and non-cattle owning households, to determine differences in perception towards wildlife. Chi-square and Cramer`s V tests were used to test if there is an association and relationship between the households` opinion and cattle ownership. For empirical analysis, factor analysis and multinomial logistic regression models were run with SPSS. Attitudes and perceptions were analysed by the Likert-scale numbered from 1 to 4. High scores (i.e. 3 and 4) indicated negative attitudes and low scores (i.e. 1 and 2) indicated positive attitudes. The factor analysis managed to reduce the number of attitude variables fitted into the model from 29 to 9 factors (components), that were used in the multinomial logit model analysis. Results from the multinomial regression indicated that demographic factors such as age, gender, education, occupation, marital status, monthly income and cattle ownership had a significant impact in distinguishing between pairs of groups and the contribution which they make to change the odds of being in one dependent variable group rather than the other. Results from factor analysis (component variables or factors) also had a significant impact on the dependent variables when applied to multinomial logit regression. About 59% of the sampled households showed positive attitudes towards integrated wildlife-based land-use practices, and indicated willingness to participate in it. Those who had negative attitudes and were not likely to participate were 13%; and those who were uncertain on whether or not to participate were 28%. Looking at the results of the empirical analysis derived from regression analysis through multinomial logit, several factors were found to have influenced whether or not households were likely to participate in the integrated wildlife/livestock land-uses. Variables: damages caused by wild animals on crops and vegetables; giving land and stopping farming to allow for wildlife conservation; roles and opportunities of wildlife in the community; roles and opportunities of livestock in the community; age of household head; occupation of household head; gender of household head; cattle ownership; Access to market, income earned from sale of livestock, and state of grazing area, were found to be significant (at different significant levels 1%, 5% and 10%) in determining whether or not households were likely to participate in the integrated wildlife/livestock land-uses. However, variables: Government support and the number of people benefiting from livestock, Interest in wildlife protection, Relationship between wildlife, human and domestic animals and land ownership were found to be insignificant in determining whether or not households were likely to participate in the integrated wildlife/livestock land-uses. Most of the households showed interest in participating in wildlife-based land-uses irrespective of whether or not they own cattle. Some households indicated dislike of the proposed land-use practice, mainly those who practiced cattle and crop production, as they perceived wild animals as a high risk to their stock. However, this negative attitude can be managed if benefits to households and community are clearly defined and compensation for loses from wildlife are made a priority. Cooperation of all stakeholders (for example, community, government, conservationists and foreign donor’ agencies) is recommended for implementation of wildlife-based land-uses.
164

Northern conservation and tourism : the perceptions of Clyde River Inuit

Nickels, Scot, 1959- January 1992 (has links)
No description available.
165

Movements, Survival, and Habitat Relationships of Snowshoe Hares Following Release in Northeast Ohio

Swanson, Kevin Allen January 2002 (has links)
No description available.
166

Dynamics of a seed dispersal mutualism between avian seed-hoarders and nut-bearing trees: Implications for oak management and American chestnut restoration

Wright, James Robert 24 August 2022 (has links)
No description available.
167

Vulnerability of longfin inshore squid (Loligo pealeii) to predation: The influence of relative prey size and behavior

Staudinger, Michelle Dana 01 January 2010 (has links)
Cephalopods provide forage to a wide range of predators in marine food-webs. Despite their ecological importance, a basic understanding of the mechanisms controlling predation risk and demand is lacking. This is true of one of the most common species of squid found in the northwest Atlantic, the longfin inshore squid (Loligo pealeii). In this dissertation, I address this shortcoming by investigating the role that size and behavior play in influencing squid’s vulnerability to predation. I used long-term food habits, population survey, and commercial landings data, to quantify size-based patterns of predation respective to 25 species of predators. Additionally, I estimated the amount of overlap between predatory consumption and the fishery catch for squid by size. I found that finfish and elasmobranchs generally consumed juvenile and sub-adult squid, while marine mammals primarily targeted adults. Consequently, marine mammals had the highest overlap with the fishing industry for squid size resources. Although large squid were not common in predator diets, predators did not appear to be gape-limited when feeding on squid. This suggested that other factors, including behavior, were important in shaping size-based patterns of predation. I used a laboratory-based approach to quantify attack and capture behaviors towards squid by two predators representing contrasting foraging tactics. Bluefish (Pomatomus saltatrix) and summer flounder ( Paralichthys dentatus) were chosen as cruising and ambush predators, respectively. Patterns in attack rates suggested that size-selection on squid was constrained by passive processes rather than active choice in both predators. Size-dependent profitability functions were calculated by combining capture success rates, handling times, and relative prey mass, and determined that bluefish was the more efficient predator of squid. Lastly, I evaluated the occurrence and effectiveness of anti-predator responses used by squid in the presence of bluefish and flounder. Squid behavior depended on the type of predator present, and the survival value of primary and secondary defense behaviors differed during interactions with each predator. The results of this project are intended to improve the quality of management of squid and their predators by providing a better understanding of predator-prey interactions in the northwest Atlantic.
168

Ecology and conservation of Sumatran elephants (Elephas maximus sumatranus) in Sumatra, Indonesia

Sitompul, Arnold Feliciano 01 January 2011 (has links)
Sumatran elephant (Elephas maximus sumatranus) continue to decline due to habitat loss, poaching and conflict with humans. Yet, developing effective land conservation strategies for elephants is difficult because there is little information available on their foraging ecology, habitat use, movements and home range behaviors. Using the lead animal technique, 14 free-ranging, tame elephants at the Seblat Elephant Conservation Center (ECC) were observed for 4,496 hours to describe their foraging ecology and diet. The majority of their daily activity was feeding (82.2 ± 5.0%), followed by moving (9.5 ± 4.0 %), resting (6.6 ± 2.1%) and drinking (1.7 ± 0.6%), and individual activity budgets varied among individuals for all activities. At least 273 plant species belonging to 69 plant families were eaten by elephants and five plant families of Moraceae, Arecaceae, Fabaceae, Poaceae, and Euphorbiaceae were most commonly consumed. Elephants browsed more frequently than grazed, especially in the wet season. Levels of crude protein, calcium, phosphorus and gross energy in plants eaten by elephants in Seblat appeared adequate for meeting the nutritional requirements. Home range size of an adult female elephant in the SECC during 2007–2008, was 97.4 km2 for the MCP and 95.0 km2 for the 95% fixed kernel. There were no relationships between average monthly elephant home range sizes or movement distances with rainfall. Distances to rivers and ex-logging roads had little effect on elephant movements, but vegetation productivity, as measured by the Enhanced Vegetation Index, did affect elephant movements. We used resource selection and compositional analysis habitat ranking approaches to describe adult female elephant habitat use in the SECC. The elephant used medium canopy and open canopy forests more than expected; however, during the day closed canopy forests were used more than at night. Locating and capturing wild elephants in tropical rainforest environments are difficult and high-risk tasks. However, using tame elephants improves the search efficiency of finding wild elephants in dense forests and reduces risks to staff and target elephants. Use of experienced veterinarians and standing sedation techniques also greatly reduce the risks of elephant injury while immobilizing elephants.
169

Existing and alternative approaches to reducing bycatch of marine mammals

Werner, Timothy Bowen 16 February 2024 (has links)
Commercial fishing results in the incidental capture, injury, and mortality of marine mammals. Often, this occurs at levels constituting an existential threat to individual populations or species. One solution to this global problem is gear modification, which is generally the preferred strategy of the fishing industry. Gear modifications can sometimes achieve bycatch reduction, but commonly suffer from several important limitations: (a) they are often narrowly focused on individual species or populations, have limited applicability to others, and often carry risks to other marine species and ecosystems; (b) they may be implemented in the absence of adequate scientific assessment of their efficacy; (c) testing new gear can actually subject threatened species to increased bycatch risk, a problem compounded by the extreme difficulty of obtaining adequate sample sizes; and (d) a disproportionate focus of this work occurs in developed countries, even though most of the world’s fishing sector (98%) is located in developing countries, as are many of the marine mammals threatened by bycatch. Here, I present global reviews of techniques for reducing marine mammal bycatch in gillnets, and for large whales in multiple gear types. Next, I present results from a field study in a small-scale non-industrial gillnet fishery, in which the catch and bycatch are compared between traditional gillnets and an alternative gear (pots). The most commercially valuable fish species were caught in both, however with differences in size class selectivity. Switching gears may represent a more promising approach than making incremental modifications to existing ones. Lastly, I employ a new computer model that simulates conflicts between the endangered North Atlantic right whale (Eubalaena glacialis) and fishing lines. The model examined their tensile strength under different entanglement scenarios, as an aid for evaluating the potential of using ropes with reduced breaking strength that are practical for fishing but allow large baleen whales to break free if entangled. The results support the use of these “whale-release” ropes to reduce entanglement risk within a large subsector of the US east coast lobster fishery. These studies highlight the benefits of applying new tools and strategies for reducing marine mammal bycatch.
170

Understanding the terrestrial carnivore community composition and distribution in Southeastern Ohio

Rich, Mackenzie E. 04 September 2017 (has links)
No description available.

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