231 |
Investigating Methods to Reduce Black Bear (Ursus americanus) Visitation to Anthropogenic Food Sources: Conditioned Taste Aversion and Food RemovalSignor, Kari D. 01 December 2009 (has links)
Conflicts between humans and black bears (Ursus americanus) jeopardize the safety of both humans and bears, especially when bears become food-conditioned to anthropogenic food sources in areas such as campgrounds. Interest in using non-lethal techniques, such as aversive conditioning, to manage such conflicts is growing. I conducted a captive experiment at The Wildlife Science Center in Minnesota and two field experiments in the La Sal Mountains, Utah, to investigate the effects of taste aversion conditioning using thiabendazole (TBZ) with a novel flavor cue and food removal on black bear food consumption and visitation to human food sources. In 2007, I conducted food trials with 6 captive black bears (3 control, 3 treatment). Controls received 1 kg baked goods scented with a peppermint-canola oil mixture and treatments received 1 kg baked goods also scented with a peppermint-canola oil mixture but mixed with 10-20 g TBZ. In the 2007 field experiment, I baited 24 field sites with 300 g of baked goods during a baseline phase for approximately 3 weeks. Half of these sites were then treated with 10 g of TBZ and camphor during a treatment phase for 4 weeks. In 2008, I baited 22 sites with 300 g of baked goods during a baseline phase for approximately 4 weeks. I then removed food and discontinued baiting at half of the sites for 4 weeks. Infrared cameras and barbed-wire hair snags were established at field sites to document bear visitation. I did not establish taste aversion in treated bears in captivity and bears fully consumed food in the majority of trials. Treating food supplies with 10 g TBZ and camphor flavor did not significantly reduce bear visitation (P = 0.615) or food consumption at field sites (P = 0.58). However, I observed a significant reduction in bear activity at sites where food was removed (P = 0.006). Potential reasons for my failure to reduce bear visitation using thiabendazole include insufficient conditioning, reluctance of bears to desist in investigating sites that previously contained untreated food, and masking of a treatment effect due to continued encounters of sites by new individuals.
|
232 |
From reformations to progressive reforms paradigmatic influences on wildlife policy in Yellowstone National Park /Turney, Elaine C. Prange. January 2007 (has links) (PDF)
Thesis (Ph.D.)--Texas Christian University, 2007. / Title from dissertation title page (viewed Dec. 10, 2007). Includes abstract. Includes bibliographical references.
|
233 |
Conserving and restoring wildlife in fragmented urban landscapes: A case study from Brisbane, AustraliaGarden, Jenni Unknown Date (has links)
No description available.
|
234 |
Changing Patterns of Rangeland Use: Functional Characteristics of the Economics and Operations of Fee Hunting Enterprises in Central and South TexasSultenfuss, Sherry D. 2009 May 1900 (has links)
Ranching communities in Texas have long recognized fee hunting as a natural resource with the potential of directly affecting agricultural incomes. Hunting as an industry today, appears to be developing into an economic substitute for Texas ranchers who are accustomed to the variable nature of agricultural markets. To determine the economic impact of this market relative to its functional utilization by landowners, this research analyzed a large group of landowners in Central and South Texas. Information was collected through a personal interview process of 146 landowners. Data collected primarily related to the individual landowners' specific fee hunting operations and the economics associated with their enterprise operations. Response data was tabulated and examined through use of comparative analysis and bivariate methods when appropriate. Output yielded a descriptive demographic profile of landowners along with landowner opinion/attitude on ensuing constraints and values of enterprise operations. Additionally, costs and returns to operations were summarized through development of an enterprise budget by ecoregion. From this analysis, it became clear that many landowners possess strong 'feelings' about their lands and appear to share parallel ideologies relative to their properties as an earned entitlement and privilege to be passed along to their heirs. However, these Texas ranchers are well aware of the economic pressures under which they must operate and their commitment to sound land management practices increasingly includes wildlife management. This, much in part, is due to the dramatic increase in revenues generated by fee hunting enterprises over the past decade. However, the budget analysis indicates possible constraints when landownership size becomes smaller such as through the sale of parcels for business purposes or through inheritance.
|
235 |
Testing the existence and extent of impacts of double-crested cormorant (Phalacrocorax auritus) nesting on three islands in Lake ErieMcGrath, Darby January 2009 (has links)
Abstract
Managing protected areas requires consideration of broad scale social, ecological and in some cases, political factors. Additionally, the impacts of hyperabundant species is often a concern in protected areas as increases in breeding and foraging pressures can alter habitats dramatically. The influences of hyberabundant nesting colonies of waterbird species are well documented. Many studies indicate that waterbird species can influence canopy species as especially on the shoreline of islands, where the most abundant nesting pressures occur. On Lake Erie, Phalacrocorax auritus populations have increased dramatically from a low of 87 nests in 1979 to 16,050 nests in 2007. However, most studies have failed to address the influences that mature tree death may have on the ground layer ecosystem, including increased litter depth, herbaceous species composition and abundance and seed bank composition and viability. Consequently this study sought to quantify the nesting colonies’ influence on coarse woody litter and how nest densities and litter depth influence the herbaceous layer, the seed bank composition and viability across the extent of three Lake Erie islands.
My study was designed to quantify the nesting colonies’ influence on these variables across the extent of each island, rather than just the perimeters where the majority of cormorant nests and visible damage exists. I collected my data in the summer of 2008 on East Sister Island, Middle Island and West Sister Island, using plotless-point quarter method, herbaceous layer surveys (incorporating data collected by Parks Canada and Ontario Parks in 2004 and 2007), cormorant nest counts, soil seed bank cores, and litter depth measurements. To test whether there are specific impacts of cormorant nests relegated to the island perimeters versus the rest of the island, an available subset of data on East Sister Island and Middle Island were used. These were expressed as vegetation ‘damage indices’ as classified by Parks Canada and Ontario Parks staff. Kruskal-Wallis tests were used to determine if the different damage indices reveal any influence of cormorant nest density in smaller localized areas as opposed to testing the entirety of the islands. Kruskal-Wallis tests indicated that, island-wide, none of the herbaceous species abundance, diversity (total, native or exotic), seed bank composition, or seed viability has been affected significantly (P > 0.05) by either cormorant nest numbers or large-diameter litter-fall from cormorant nesting activities. However, damage indices (calculated using aerial photography) did indicate that, P .auritus nest density does influence litter depth, herbaceous species abundance and diversity in the island perimeter. Nest density has not significantly affected seed bank abundance or seed viability. My conclusion is that cormorants do not uniformly affect the islands as there is localized damage to the herbaceous layer, restricted primarily to the perimeters of the islands. However, there remains a risk to the interior herbaceous layer of the island if the effects of nesting pressures at the edges advance inward from this perimeter.
|
236 |
Assessing Changes in the Abundance of the Continental Population of Scaup Using a Hierarchical Spatio-Temporal ModelRoss, Beth E. 01 January 2012 (has links)
In ecological studies, the goal is often to describe and gain further insight into ecological processes underlying the data collected during observational studies. Because of the nature of observational data, it can often be difficult to separate the variation in the data from the underlying process or `state dynamics.' In order to better address this issue, it is becoming increasingly common for researchers to use hierarchical models. Hierarchical spatial, temporal, and spatio-temporal models allow for the simultaneous modeling of both first and second order processes, thus accounting for underlying autocorrelation in the system while still providing insight into overall spatial and temporal pattern. In this particular study, I use two species of interest, the lesser and greater scaup (Aythya affnis and Aythya marila), as an example of how hierarchical models can be utilized in wildlife management studies. Scaup are the most abundant and widespread diving duck in North America, and are important game species. Since 1978, the continental population of scaup has declined to levels that are 16% below the 1955-2010 average and 34% below the North American Waterfowl Management Plan goal. The greatest decline in abundance of scaup appears to be occurring in the western boreal forest, where populations may have depressed rates of reproductive success, survival, or both. In order to better understand the causes of the decline, and better understand the biology of scaup in general, a level of high importance has been placed on retrospective analyses that determine the spatial and temporal changes in population abundance. In order to implement Bayesian hierarchical models, I used a method called Integrated Nested Laplace Approximation (INLA) to approximate the posterior marginal distribution of the parameters of interest, rather than the more common Markov Chain Monte Carlo (MCMC) approach. Based on preliminary analysis, the data appeared to be overdispersed, containing a disproportionately high number of zeros along with a high variance relative to the mean. Thus, I considered two potential data models, the negative binomial and the zero-inflated negative binomial. Of these models, the zero-inflated negative binomial had the lowest DIC, thus inference was based on this model. Results from this model indicated that a large proportion of the strata were not decreasing (i.e., the estimated slope of the parameter was not significantly different from zero). However, there were important exceptions with strata in the northwest boreal forest and southern prairie parkland habitats. Several strata in the boreal forest habitat had negative slope estimates, indicating a decrease in breeding pairs, while some of the strata in the prairie parkland habitat had positive slope estimates, indicating an increase in this region. Additionally, from looking at plots of individual strata, it seems that the strata experiencing increases in breeding pairs are experiencing dramatic increases. Overall, my results support previous work indicating a decline in population abundance in the northern boreal forest of Canada, and additionally indicate that the population of scaup has increased rapidly in the prairie pothole region since 1957. Yet, by accounting for spatial and temporal autocorrelation in the data, it appears that declines in abundance are not as widespread as previously reported.
|
237 |
Testing the existence and extent of impacts of double-crested cormorant (Phalacrocorax auritus) nesting on three islands in Lake ErieMcGrath, Darby January 2009 (has links)
Abstract
Managing protected areas requires consideration of broad scale social, ecological and in some cases, political factors. Additionally, the impacts of hyperabundant species is often a concern in protected areas as increases in breeding and foraging pressures can alter habitats dramatically. The influences of hyberabundant nesting colonies of waterbird species are well documented. Many studies indicate that waterbird species can influence canopy species as especially on the shoreline of islands, where the most abundant nesting pressures occur. On Lake Erie, Phalacrocorax auritus populations have increased dramatically from a low of 87 nests in 1979 to 16,050 nests in 2007. However, most studies have failed to address the influences that mature tree death may have on the ground layer ecosystem, including increased litter depth, herbaceous species composition and abundance and seed bank composition and viability. Consequently this study sought to quantify the nesting colonies’ influence on coarse woody litter and how nest densities and litter depth influence the herbaceous layer, the seed bank composition and viability across the extent of three Lake Erie islands.
My study was designed to quantify the nesting colonies’ influence on these variables across the extent of each island, rather than just the perimeters where the majority of cormorant nests and visible damage exists. I collected my data in the summer of 2008 on East Sister Island, Middle Island and West Sister Island, using plotless-point quarter method, herbaceous layer surveys (incorporating data collected by Parks Canada and Ontario Parks in 2004 and 2007), cormorant nest counts, soil seed bank cores, and litter depth measurements. To test whether there are specific impacts of cormorant nests relegated to the island perimeters versus the rest of the island, an available subset of data on East Sister Island and Middle Island were used. These were expressed as vegetation ‘damage indices’ as classified by Parks Canada and Ontario Parks staff. Kruskal-Wallis tests were used to determine if the different damage indices reveal any influence of cormorant nest density in smaller localized areas as opposed to testing the entirety of the islands. Kruskal-Wallis tests indicated that, island-wide, none of the herbaceous species abundance, diversity (total, native or exotic), seed bank composition, or seed viability has been affected significantly (P > 0.05) by either cormorant nest numbers or large-diameter litter-fall from cormorant nesting activities. However, damage indices (calculated using aerial photography) did indicate that, P .auritus nest density does influence litter depth, herbaceous species abundance and diversity in the island perimeter. Nest density has not significantly affected seed bank abundance or seed viability. My conclusion is that cormorants do not uniformly affect the islands as there is localized damage to the herbaceous layer, restricted primarily to the perimeters of the islands. However, there remains a risk to the interior herbaceous layer of the island if the effects of nesting pressures at the edges advance inward from this perimeter.
|
238 |
Democracy and Sustainable Development in wildlife management : From ‘stakeholders’ to ‘citizens’ in the Swedish wolf restoration processvon Essen, Erica January 2012 (has links)
In an attempt to lend legitimacy to the troubled wolf project and to root policies in wolf-affected counties, decision-making was decentralized to stakeholder-based county wildlife management delegations in Sweden in 2009. Drawing from Habermas’ critical theory, this paper suggests that a phenomenon of instrumental rationality is currently circumscribing free and open deliberation in these delegations. Consequently, stakeholders remain fixed in their predetermined positions as wolf-skeptic hunters or pro-wolf conservationists, unable to be swayed by the deliberative process. The aim of this paper is to identify the barriers to deliberation that account for the perseverance of this strategic stakeholder rationality. Three county wildlife delegations are investigated as examples of this. The paper identifies the following four barriers, which are traced to instrumentality: strong sense of accountability, overly purposive atmosphere, overemphasis on decision as final outcome and perceived inability on the part of the delegates to influence decision-making, which is found by and large to still be ruled by scientists. Through these findings, it suggests that such barriers cause delegates to censor their own discursive attempts and to act with strategic rather than with communicative rationality toward the decision-making process. Finally, the paper concludes that the effect of instrumentality in these delegations is currently leading to (1) a crisis of legitimacy for the wolf project, as according to Habermas’ theory and (2) reduced individual freedom under the pursuit of sustainable development, as freedom has been confined to the dimension of the protection and promotion of private interests.
|
239 |
Citizen-Based Sea Turtle Conservation Across the Developing-Developed World DivideCornwell, Myriah Lynne January 2011 (has links)
<p>This dissertation research explores participatory sea turtle conservation monitoring through a comparison of two case studies, one in North Carolina (NC), USA and the other in Baja California Sur (BCS), Mexico. Participatory approaches in conservation management can supplement state capacity as well as strengthen the involvement of citizens in environmental governance and knowledge production. Despite scholarship challenging the validity of the categories of developing and developed nations, this categorical assumptions derived from this binary world divide continue to inform conservation, and theoretical vocabularies for local roles in conservation management. In developed nations, participatory conservation management is framed through the broader administrative rationalism discourse, and is identified as volunteer conservation or citizen science. In developing nations, participatory conservation management is approached through the discourse of biodiversity and the threats human society poses to it, and is identified through community-based processes of conservation stewardship. The two case studies analyzed in this dissertation serve to interrogate the ways in which these distinct discourses influence outcomes, and consider what may be obscured or overlooked due to discursive constraints. </p><p> Conducting ethnographic research in each case study site, I participated in and observed sea turtle conservation activities and conducted in-depth interviews with relevant sea turtle conservation actors as well as collected documents pertaining to the conservation programs. Sea turtle conservation monitors in NC and BCS perform functionally similar conservation tasks, and I collected data using similar techniques in order to maximize comparability. I compare the case studies, not to generalize to a population, but instead to speak to theoretical propositions and inform existing theory on participatory conservation monitoring. </p><p> Although participatory monitoring in NC and BCS does not result in a democratization of science, there are beneficial outcomes to participants in both places. NC sea turtle monitors are enabled to take ownership of sea turtle stewardship, and BCS sea turtle monitors are enabled to promote conservation and cultural change using the authority of science. These outcomes challenge assumptions about state capacity and local engagements with science in participatory conservation, and the disparate approaches to local roles in conservation in each `world.' The overall findings suggest that a multitude of factors are involved in the production of conservation program frameworks and participant outcomes, and more deeply interrogating the taken for granted assumptions behind conservation designs and implementation can offer stronger understandings of what participatory conservation management can (and cannot) achieve.</p> / Dissertation
|
240 |
Changing Patterns of Rangeland Use: Functional Characteristics of the Economics and Operations of Fee Hunting Enterprises in Central and South TexasSultenfuss, Sherry D. 2009 May 1900 (has links)
Ranching communities in Texas have long recognized fee hunting as a natural resource with the potential of directly affecting agricultural incomes. Hunting as an industry today, appears to be developing into an economic substitute for Texas ranchers who are accustomed to the variable nature of agricultural markets. To determine the economic impact of this market relative to its functional utilization by landowners, this research analyzed a large group of landowners in Central and South Texas. Information was collected through a personal interview process of 146 landowners. Data collected primarily related to the individual landowners' specific fee hunting operations and the economics associated with their enterprise operations. Response data was tabulated and examined through use of comparative analysis and bivariate methods when appropriate. Output yielded a descriptive demographic profile of landowners along with landowner opinion/attitude on ensuing constraints and values of enterprise operations. Additionally, costs and returns to operations were summarized through development of an enterprise budget by ecoregion. From this analysis, it became clear that many landowners possess strong 'feelings' about their lands and appear to share parallel ideologies relative to their properties as an earned entitlement and privilege to be passed along to their heirs. However, these Texas ranchers are well aware of the economic pressures under which they must operate and their commitment to sound land management practices increasingly includes wildlife management. This, much in part, is due to the dramatic increase in revenues generated by fee hunting enterprises over the past decade. However, the budget analysis indicates possible constraints when landownership size becomes smaller such as through the sale of parcels for business purposes or through inheritance.
|
Page generated in 0.1142 seconds