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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.
311

Development of an Innovative Statewide Population Monitoring Program for Mule Deer

Bernales, Heather H. 01 May 2010 (has links)
Monitoring population trend and estimating vital demographic parameters are essential for effective management of a mule deer (Odocoileus hemionus) population. Because of financial constraints, many wildlife agencies use computer models to obtain indirect indices of population size and trend as an alternative to annual field-based estimates of population size. These models are based primarily on herd composition counts and harvest rates from hunter-harvest surveys, and are rarely field validated. I developed an alternative method for monitoring population dynamics of wintering populations of mule deer. I designed a hybrid monitoring program that combined annual vital rate monitoring to track changes in population growth rate with a field-based approach for estimating population abundance. The program allocated resources optimally towards the most critical components of mule deer population dynamics, and consisted of 4 field surveys: annual monitoring of age ratios, overwinter fawn survival, and annual doe survival, with field-based estimates of population size only once every 4 years. Surveys were conducted from 2006 to 2008 in Wildlife Management Unit (WMU) 2, Utah, and cost $29,298 per year, prorated over 4 years. Unfortunately, financial constraints prohibit the implementation of this monitoring program in every WMU in Utah. Instead, the program can be implemented in select WMUs throughout the state, with survival data collected in these core units, providing estimates for nearby satellite units. To establish core-satellite unit pairs, I developed a proxy method for determining correlation in survival rates between core and satellite units using model-simulated estimates. I demonstrated this core-satellite method using WMU 2 as a core and WMU 3, an adjacent unit, as a satellite. Finally, I compared a multiple data sources (MDS) model with a herd composition-based population model, POP-II. The MDS model better approximated observed data, and provided statistical rigor. Overall, the hybrid program was less costly and provided more precise estimates of population trend than could be achieved with a monitoring program focused on abundance alone, and was more defensible than herd composition monitoring. After establishing correlations in doe and fawn survival between core and satellite units, data collected in core units via the hybrid program could then be used to model the mule deer population dynamics of other units using MDS modeling procedures. This combined approach could be an effective statewide program for monitoring mule deer populations.
312

Identifying and Understanding the Spatial Distribution of Bobcat and Coyote Behavior

Wilson, Ryan Radford 01 May 2010 (has links)
A common observation in animal space use studies is that animals do not use space uniformly, but rather use some areas of their home ranges and territories with much higher intensity than others. Numerous methods have been developed to estimate these "core areas"; however, all of the current methods available are based on arbitrary rules. Additionally, most studies do not attempt to understand what behavioral processes lead to the observed patterns of non-uniform space use. This study has four main objectives: 1) to develop an objective and more precise method for estimating core areas, 2) to understand the processes leading to unequal coyote capture probabilities across territories, 3) to understand the biological mechanisms that influence the location of bobcat core areas, and 4) to determine how differences in territory size affect coyote movement patterns. The core area estimation method I developed consistently performed better than methods using arbitrary values to define core areas. Using this method to estimate coyote core areas, I determined that coyote capture locations were not actually biased towards low use areas because of low familiarity with those areas, but rather because of a higher probability of encountering traps there. Intensity of coyote use did, however, influence the location of bobcat core areas. When prey abundance was high, bobcat core areas were located in areas of low coyote use but occurred in areas of high coyote use when prey abundance was low, indicating bobcat core areas are the result of at least two processes: foraging conditions and avoidance of intraguild predation. Lastly, coyote movement behavior changed significantly as territory size increased, leading to faster and straighter movement patterns. However, even though coyotes in larger territories moved twice as fast as those in small territories, they took significantly longer to traverse their territories compared to those in small territories. This might be the result of coyotes occupying large territories being less constrained by defense due to lower conspecific density compared to coyotes occupying small territories. Overall, my research reveals the importance of using more precise methods to delineate animal space use patterns, and the greater information researchers can obtain when they attempt to understand the processes underlying space use patterns.
313

Ecology and Seasonal Habitat Use Patterns of Columbian Sharp-Tailed Grouse in Northern Utah

Greer, Ron D. 01 May 2010 (has links)
Columbian sharp-tailed grouse (Tympanuchus phasianellus columbianus: hereafter sharp-tailed grouse) populations have been declining. These declines have been attributed to a number of factors, including habitat loss due to agriculture, habitat fragmentation, overgrazing by livestock, and the loss to fire. To gather information about their status in northern Utah, I radio-marked sharp-tailed grouse in 2003 (n=15) and 2004 (n=20) in two research areas. The study areas were located on the south end of Cache County and in eastern Box Elder County. In the Cache study area, I monitored 7 males and 1 female in 2003, and 6 males and 3 females in 2004. In the Box Elder study area, I monitored 6 males in 2003 and 6 males and 5 females in 2004. I then located the radio-marked sharp-tailed grouse using telemetry and collected Visual Obstruction Readings (VOR) and vegetation data on each flush site and on a randomly selected paired point. I completed an unsupervised classification of the two study areas to determine if habitats were used more than would be expected based on availability. I then used a paired point linear regression to determine if vegetation parameters were correlated with sharp-tailed grouse on the landscape. Sagebrush in the Box Elder County study area and forbs in the Cache County study area were significantly correlated with habitat use by sharp-tailed grouse. The VOR readings were higher at the flush sites than at the paired points. The unsupervised classification showed that in Box Elder County, sagebrush was used in greater proportion than is available, while in the Cache County study area there were no habitat types that were used in greater proportion than was available on the landscape. I collected information on nest sites, nest success, broods, and mortality of these 2 populations. Nest success was 75% combined over the 2-year study, and mortality was 72% for both populations over the 2 years. Seasonal habitat use and distance travelled were determined using Global Positioning System points collected at every flush point. The distance traveled ranged from 0.9 km to 14.7 km, with the longest distance being travelled in the winter.
314

A Survey of Employees of the United States Department of Agriculture's Animal Damage Control Program

Schroeder, Susan A. 01 May 1996 (has links)
This study examined the attitudes of employees of the United States Department of Agriculture's Animal Damage Control (ADC) Program. This research examined ADC employees' attitudes about wildlife, the ADC program and ADC employment, wildlife damage management methods, euthanasia and the killing process, and the role of various public and private groups on ADC policy. This study also applied the theory of organizational capture to the ADC program to test its utility in explaining the attitudes and behaviors of employees. Results were based on a survey of ADC employees conducted in January 1995. Survey responses were analyzed to explore associations between employee attitudes and job type or time of service at ADC. Job type was found to be a better indicator of employee attitudes than time of service. Field and management employees tended to have more positive views of ADC and ADC employment compared with research employees. Respondents with different job types perceived different levels of effectiveness and humaneness for wildlife control methods. In general, field employees viewed lethal techniques as more effective and humane than research employees. Similarly, research employees reported nonlethal techniques to be more effective and humane than field employees. Finally, research employees felt that outside interest groups should have more influence on ADC practices than field and management employees felt they should. ADC employees were found to have some characteristics indicative of organizational capture. They had a homogeneous client base, and were resistant to reaching out to nontraditional clients in the face of opposition from traditional clients. However, they were not deflected from the ADC mission. Because respondents indicated conformity to the ADC mission, ADC was found to be at most variably captured by its traditional farming and ranching clientele.
315

A history of wildlife management practices in British Columbia to 1918

Ball, Georgiana Genevieve 18 October 2019 (has links)
This thesis traces the evolution of wildlife manage­ment practices in British Columbia from pre-contact times to 1918. The aboriginal people employed certain measures to restrict the killing of their most valuable species, particularly salmon and beaver. They also practised environmental control to enhance deer and elk habitat. Indians were able to do this with success because most tribes recognized strict territorial rights to fishing and hunting areas by clans or families. Fierce protection of these monopoly rights prevented such practices as poaching, which would have made conservation measures futile. Because these rights were inherited, hunters and fishermen were obliged to preserve species in their care. This system of monopoly control continued after the Hudson's Bay Company acquired exclusive trading rights in the land west of the Rockies. The company recognized Indian territorial rights and used them to continue the sustained-yield harvesting of beaver in New Caledonia, and to promote the recovery of beaver stocks in the Peace River district where beaver had been depleted during the fur trade rivalry. The period of monopoly control came to an end in 1858-59 when the Hudson's Bay Company lost its exclusive trading rights. During the colonial and early provincial period, the responsibility for management controls fell to the public authorities. The initial efforts by government to restrict the hunting and sale of game was generally ineffectual because law enforcement was difficult in the sparsely settled province and because the entrepreneurial climate of the late nineteenth century was conducive to resource exploitation. Although public regulations in the nineteenth century failed to protect adequately popular species of game, sportsmen, who subscribed to the lifestyle of the British landed gentry, began introducing exotic game and private shooting preserves to the province, following the practice in Europe. They also organized game protective associations, which led the public demand for the cessation of market-hunting excesses and the appointment of government game wardens. During his tenure from 1905 to 1918, the first provincial game warden, A. Bryan Williams, made public control of game conservation a reality in much of the province. He built a department of capable deputies whose efforts annually multiplied convictions of game law infractions. At the same time, Williams constantly stressed the economic importance of game and widely advertised the province's sporting attractions. Under his direction, the government established three public game reserves. It also commenced the control of game predators and the patrol of border areas. Most importantly, Williams inaugurated the principle of game users paying for game protection through a system of licenses. By 1918 most of the public recognized govern­mental responsibility for the management of wildlife. This thesis suggests that wildlife received the most consistent and effective management when their habitat and harvest were subject to the monopolistic control of the users. It also reveals that the history of wildlife management in British Columbia did not adhere closely to the universal sequence of measures observed by Aldo Leopold, the recognized founder of the discipline of wildlife management. The paper concludes that a mixture of private and public wildlife management areas may be the most appropriate means of satisfying the various attitudes and interests of British Columbia citizens who are concerned with wildlife. / Graduate
316

The Ecological Drivers of Urban Tick-Borne Disease Emergence

VanAcker, Meredith Cathline January 2022 (has links)
Tick-borne diseases cause in enormous burden on human, livestock, and wildlife health globally and are driven by the increasing abundance and geographic expansion of medically important tick species. More recently, tick-borne disease emergence is occurring in urban landscapes due to complex feedbacks between the environment, humans, wildlife, and ticks. In this dissertation, I focus on the ecological conditions that allow for tick-borne disease emergence in a city. I use a combination of spatial landscape modeling, empirical data collection, wildlife movement tracking to determine drivers of zoonotic hazards in New York City, NY, and employ vector genomics to examine vector dispersal in the northeastern United States. In chapter one, I pair tick collection throughout the five boroughs of New York City with landscape connectivity modeling to examine how green space connectivity and habitat availability affects the density and infection of questing nymphs – an important epidemiological measure of human risk for tick-borne diseases. I found that green spaces that were highly connected for deer had higher nymph density and infection prevalence for Borrelia burgdorferi sensu stricto, the etiologic agent of Lyme disease. In chapter two, I use camera trapping, live trapping, and tick collection on Staten Island, NY, to examine how landscape fragmentation – through changing habitat size and connectivity – shapes the host community available for questing Ixodes scapularis nymphs. Further, I examined whether patterns in host species abundance and activity correlate with the density of nymphs and their infection prevalence with three different pathogens that vary in host-specificity, B. burgdorferi, Babesia microti, and Anaplasma phagocytophilum. I found associations between host species and the size and connectivity of the park habitat, identified host species which amplified and removed ticks in the environment, and determined links between host activity and abundance and the infection prevalence of nymphs with host-specific pathogens. In chapter three, I utilize movement data from 59 white-tailed deer on Staten Island, NY, to assess the drivers of movement and its impact on tick-borne disease hazard across the landscape. I found that white-tailed deer avoid anthropogenic development at fine spatial scales when establishing home ranges but select for anthropogenic resources within their home range, increasing the potential to distribute ticks into environments that interface with humans. Finally in chapter four, I use double digest Restriction Associated DNA sequencing to examine the genetic differentiation of six I. scapularis populations across the Northeast region. I found high levels of gene flow across a spatial scale of 400 km, likely resulting from frequent host-mediated dispersal events combined with large I. scapularis populations. Taken together, this work emphasizes that host movement and ecology are critical determinants of urban tick-borne disease emergence through directing vector and pathogen dispersal, serving as pathogen reservoirs in urban habitats, and interfacing with humans in unique ways that increase human exposure to zoonotic hazards.
317

Challenges of Conserving a Wide-ranging Carnivore in Areas with Dense Road Networks

Bencin, Heidi L. January 2018 (has links)
No description available.
318

Changing Perspectives on Citizen Science Using eBird Data on Grand Bahama Island, The Bahamas.

Davis, Ancilleno Orlando 13 December 2018 (has links)
No description available.
319

Politiker, tjänstemän & vargen -Politisering och roller i viltförvaltningsdelegationer på regional nivå

Hellström, Johanna, Thelin, Johanna January 2020 (has links)
Predator policy is a controversial area that includes problems with hunting and handling of wild animals. This is the reason why the government decentralized some of the work to the regions in 1998. During 2008, the Swedish government produced a proposal regarding the conduct of wildlife management delegations. The purpose of this essay is to study the relationship between politicians and officials in the wildlife management delegation with a specific focus on a polarized issue, the wolf question. We do this by studying roles and politicization. Based on the purpose, the following questions have been formulated: What is the role of officials and politicians in wildlife management delegations? How are these roles affected by how politicized the wolf issue is in the region? These delegations include politicians and officials. Based on the theory of the dichotomy between politicians and officials, politicians have a stance and biased role, while officials have a role that is about being impartial and working on the basis of the regulations. This essay consists of a comparative case essay with a content analysis and thematic analysis as a method. The material used has been collected through semi-structured interviews and printed material. This essay shows that the politicization of the wolf question to some extent affects the representatives in the wildlife management delegation.
320

Community perspectives, Caribou user participation and the Beverly-Qamanirjuaq Caribou Management Board in Northcentral Canada

Kendrick, Anne January 1994 (has links)
No description available.

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