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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.
1

Factors affecting Western Snowy Plover winter foraging habitat selection in San Francisco Bay ponds

Pearl, Benjamin G. 24 February 2016 (has links)
<p>Within the San Francisco Bay Area, Western Snowy Plovers (<i>Alexandrinus nivosus nivosus</i>) nest and winter in former salt ponds. They face a number of threats including human-altered habitats and high levels of predation by mesopredators and raptors. The South Bay Salt Pond Restoration Project (the Project) is a large wetland restoration project that will change and potentially eliminate Snowy Plover habitat in the region. As the Project returns salt ponds to tidal wetland, there will be less of the dry, flat, and sparsely vegetated habitat that plovers need for breeding and wintering habitat. A greater understanding of the specific microhabitat requirements for high quality plover foraging sites is needed. In particular, it is important for managers to understand what constitutes high quality wintering habitat for Snowy Plover numbers. This study assessed the characteristics at sites where Snowy Plovers winter in former salt ponds, especially habitat traits related to promoting plover foraging. Analysis of plover foraging habitat showed that plovers were associated with increasing plant height, water cover, and distance from perches and levees. This information is designed to inform restoration and management decisions in efforts to meet Snowy Plover recovery goals in the South San Francisco Bay. </p>
2

The Root of Sustainability| Investigating the relationship between medicinal plant conservation and surface mining in Appalachia

Turner, Jessica B. 29 December 2015 (has links)
<p> Since European colonization, Appalachian culture has been based on resource extraction, such as coal mining, timbering, and Non-Timber Forest Product (NTFP) harvest. Surface mining degrades forest habitat for medicinal plants, especially the habitat for the internationally valuable medicinal herb, American ginseng (<i>Panax quinquefolius</i> L.), and the NTFP culture associated with this plant. The relationship between medicinal plant conservation and surface mining must be studied with a non- traditional, multi-faceted approach: culturally, economically, and ecologically. (1) Using community-based participatory surveys, I determined how ginseng harvesters and non- harvesters in West Virginia communities view the relationship between surface mining and ginseng harvest. Harvester culture is one worth preserving, as they value conservation. However, most harvesters admit to illegal harvesting practices. By determining what harvesters and non-harvesters prioritize and value, and understanding what is the most effective way to connect with these two groups, this research can aid in the development of successful environmental education and conservation outreach. (2) Challenging the perceptions that economic growth is incompatible with ecological consciousness, an economic analysis comparing the short-term gains of surface mining to the potential economic value of sustainable ginseng harvest or a large-scale ginseng farm operation was completed. Through an in-depth economic modeling approach I showed that stewarded ginseng harvest can be economically advantageous in the long-term while maintaining the integrity of the forest. (3) For reintroduction purposes, the concept of &lsquo;indicator species&rsquo; is frequently used. These species are often selected based on anecdotal information, rather than scientific rigor. In order to maximize the efficiency of ginseng reintroductions, I analyzed the ability of select putative indicators (herbs, shrubs, and trees) to serve as site and microsite predictors of ginseng growth. Most indicators were ineffective, and the ones that did show a relationship to growth were contra- indicators, predicting reduced individual plant growth. This research may aid reintroduction and agroforestry projects, and thereby reduce the frequency of reintroductions that fail because plants are introduced into suboptimal locations. (4) By experimentally reintroducing two medicinal plants, ginseng and goldenseal, to two sites with three types of disturbance history, I determined that degraded landscapes can return to a forested state that supports medicinal plant growth and reproduction, although microsite and soil conditions were found to be important to consider when reintroducing plants. As such, appropriate future land-management decisions can be made based on land-use legacy. By combining social, economic, and ecological studies, medicinal plant conservation can be implemented through the development of environmental outreach and effective reintroduction strategies.</p>
3

The Relationship of Red-Backed Salamander Abundance to the Direct and Indirect Use Value of Undisturbed Forest, a Timberland Mosaic of Forest, and Agriculture Land-Uses

Garbark, Christopher J. 24 April 2019 (has links)
<p> <i>Plethodon</i> salamanders may serve as important indicators of forest ecosystem integrity due to their niche, physiological sensitivity, abundance, site fidelity, and association with forest structures. Forest ecosystems provide direct and indirect services and products that benefit society. Monitoring the quality and status of these direct and indirect use values is important to manage and maximize the benefit to people. An ecological indicator is something that may indicate the state of a system. Indicators are widely used in a variety of fields including forestry, economics, and environmental management to monitor the state of desired systems. The IndVal method is a statistical analysis used to determine the efficacy of a species as an indicator species, by determining the association between the species of interest and site groups or habitats. I sought to determine if the red-backed salamander is an indicator of forests based on the IndVal method, and if the red-backed salamander may be used as an indicator of use values. I hypothesized that red-backed salamanders may be used as an indicator of standing mature forested areas. I hypothesized that salamander abundance would be highest in forested areas and may act as an indicator species of forest habitats. I hypothesized that red-backed salamander abundance would have a positive correlation with indirect use values and a negative correlation with direct use values. The study area consisted of Forestland, Timberland, and Agriculture land-uses within northwestern Pennsylvania. I used visual encounter surveys and drift fences for capturing of red-backed salamanders (<i>Plethodon cinereus</i>) for abundance estimates. Visual encounter surveys were done within area constrained (10 &times; 10m) plots and a time constraint of roughly 30 minutes. I measured environmental variables within each plot. An N-mixture model of <i>P. cinereus</i> was used to estimate abundance based on repeated counts data. I used a principal components analysis (PCA) to determine which environmental variables were associated with study sites. I used a Kruskal-Wallis test and post-hoc Dunn&rsquo;s test to determine differences between land-use in red-backed salamander abundance. I applied the IndVal method to red-backed salamander abundance in association to land-use and habitat. I estimated indirect use values through cost replacement methods for water purification, water cycling production, nitrate treatment, and soil erosion. I obtained direct use values through land-owners and the U.S. Forest Service archives, which the cost of production and gross value of production were used to determine the net and gross value. I used a Spearman&rsquo;s Rank correlation to determine the relationship between red-backed salamander abundance and the direct and indirect use values of land-uses. The PCA 1 axis described an environmental gradient of closed to open canopy. Forestland sites had the lowest sunlight values, Agriculture having the highest, and Timberland intermediate between the two. Canopy percent cover was the most informative variable in the N-mixture model. Red-backed salamander abundance was greatest, mean = 434, on Forestland sites and was significantly (p-value &lt; 0.05) different from Timberland and Agriculture. The red-backed salamander was highly associated with Forestland with an indicator species value of 0.876, and 0.972 for forests. Red-backed salamanders held a significant strong positive relationship with indirect use values, rho = 0.84. <i>P. cinereus</i> abundance had a significant strong negative relationship with gross direct use values, rho = &ndash;0.95, and net direct use values, rho = &ndash;0.92. The strong correlation between <i>P. cinereus</i> abundance and indirect use values suggest that red-backed salamander abundance may have applications as an indicator of indirect use values for forest ecosystems.</p><p>
4

Effects of Open Circuit Scuba Exhaust on Reef Fish Surveys in the Main Hawaiian Islands

Lopes, Keolohilani Harold, Jr. 09 August 2017 (has links)
<p> The predominant method to quantify reef fish populations is the Open Circuit SCUBA (OC) <i>in-situ</i> fish survey. However, there are many biases associated with these surveys including the expelled OC exhaust which can cause visual and audible disturbances. This study aims to evaluate the bias created by OC exhaust utilizing closed-circuit rebreather (CCR) surveys, along surveys were conducted in protected areas and fished areas. The three sites in the main Hawaiian Islands were Kealakekua Bay (KK), Old Kona Airport (OA), and P&umacr;p&umacr;kea (PK) marine life conservation district. This study found that the total fish biomass and species richness from all sites pooled showed no significant differences between gear types. However, there was a significant interaction between the gear type and the protection status (Pr(>|t|) = 0.025), indicating that there are greater differences between OC and CCR in the fished areas than the protected areas. The difference between the gear types showed a greater magnitude of OC having a higher biomass in the fished areas opposed to the protected areas where that difference was smaller. When fished species (Table 4 &ndash; a, b) were examined, significant differences between gear types were shown (Pr(>|t|) = 0.010). The OC surveys showed more fished biomass than the CCR surveys which could mean that the attraction to the exhaust within the protected areas were greater than the repulsion of the exhaust in the fished areas. Differences in the fished species biomass while having no difference in the all fish biomass supports the previous studies findings that fishing pressure is very influential on the magnitude of difference between the gear types. For researchers, estimating fishing pressure is of high importance in order to assess the level of bias associated with OC exhaust on surveys. These biases need to be accounted for in population estimations for protected areas and non-protected areas in order to get more accurate biological fish data.</p><p>
5

Seasonal home range sizes, transboundary movements and conservation of elephants in northern Tanzania

Kikoti, Alfred P 01 January 2009 (has links)
Although the unprotected lands of northern Tanzania support large numbers of elephants, and provide critical linkages for wildlife movements across the region, there is little information on the dispersal patterns of elephants in these unprotected lands. Our home range measures (100% MCP) of 21 elephants with satellite collars in four study regions were highly variable (191 to 3,698 km2). Home range sizes (95% fixed kernel) of bulls were typically larger than those of females, and wet season ranges were typically larger than dry season ranges. There were large differences in average home range sizes reflected varying strategies for obtaining food and water and avoiding humans. All eight radio-collared elephants (3 bulls, 5 females) in the West Kilimanjaro study region crossed the Tanzania-Kenya border, but typically elephants crossed more frequently in the wet than the dry season, and bulls crossed 47% more frequently than females. These extensive transboundary movements indicate that the elephant populations of West Kilimanjaro and Amboseli NP constitute a single transboundary population. Based upon 14,287 fixes from eight collared elephants, the vast majority of time was spent in unprotected (X¯ =91.5%) versus protected (X¯ =8.5%) areas. Amboseli NP was visited by all eight elephants and was the protected area most utilized (X¯ =8%, range 2-24%). Based upon the movements of 15 GPS-collared elephants in northern Tanzania, we identified eight areas that we considered important for wildlife conservation corridors/linkages for elephants. Our conservation priorities for these corridors were based upon the levels of threats and conservation potential. Community interviews and hilltop surveys were used in two Maasai villages to determine the extent of wildlife conflict, community attitudes towards elephants, and if elephants were using a vegetation corridor to move between Tanzania and southern Kenya. Elephants were the most problematic wildlife species and were considered a nuisance. However, they believed they attracted tourists, and generally did not believe elephant numbers should be reduced. Based upon elephant conflict and use and the communities' need to maintain areas for cattle grazing and medicinal plant collection, the two communities established the first wildlife conservation corridor in Tanzania.
6

The Effect of Hunter-derived Offal Piles on Local Scavengers

Huff, Christopher J. 03 August 2016 (has links)
<p> Each fall hunters kill hundreds of thousands of White-tailed Deer (<i> Odocoileus virginianus</i>) in Missouri and Illinois. Field dressing these deer provides a large influx of nutrient rich offal into the ecosystem. To date, little research has examined the effects of this resource on wildlife. We used trail cameras positioned over offal piles to examine species richness and diversity in a range of habitats during the 2011-2013 hunting seasons in Missouri and Illinois. There were a total of 17 different sampling sites, resulting in over 4 thousand photographs. Images were analyzed and organized into timed feeding events. Sites were categorized into one of three habitat types: field, edge, or forest. We documented 10 different scavenger species feeding on the offal. There was no significant difference in scavenger diversity (<i>F</i>=2.95; <i>d.f.</i>= 2,14; <i> p</i>=0.085), richness (<i>F</i>=2.25; <i>d.f.</i>2, 14; <i>p</i>=0.14;), nor habitat preference (<i>F</i>=0.51; <i> d.f.</i>2,14; <i>p</i>= 0.61) among habitat types. We also found no significant difference in the community structure of scavengers among the three habitat types (<i>R</i>= -0.049; <i>p</i>=0.64). However, there was a difference in the preferred mean feeding times of avian vs. mammalian scavengers (<i>U</i>=1,215.5; <i>Z</i>=11.24; <i> p</i>=0). The presence of offal piles does not appear to repel deer, as they were frequently observed in close proximity. The apparent similarity of the scavenger guild among habitat types can be attributable to the mosaic of fragmented habitat that characterizes the Midwest, as well as the generalized behavior of the species.</p>
7

Perspectives on wildlife from the practice of wildlife rehabilitation

Pospisil, Heather 12 November 2014 (has links)
<p> Current research about wildlife has tended to emphasize the contributions of scientific perspectives. This thesis argues that the practice of wildlife rehabilitation (WR) also offers significant information to academic discourse. The goals of my study were to explore and describe the different perspectives and knowledges generated about wildlife through the practice of wildlife rehabilitation and the rehabilitators' relationships with their wild animal patients, through the use of qualitative methods including semi-structured interviews and autoethnography. I interviewed seven WR professionals about their nonhuman animal patients, education animals, and human staff and volunteers. The autoethnographic information used in this study was gathered from my own experience as a wildlife rehabilitator. </p><p> Five key themes emerged from my research. 1) The altruistic roles taken on by wildlife rehabilitators (both caregiving and training roles) improve communication with other animal individuals. 2) The subjective experience plays critical roles, both positive and negative, in the practice of wildlife rehabilitation and the ability to understand wildlife. 3) The sense of obligation and responsibility to address anthropogenic injuries to other animals leads humans to become wildlife rehabilitators. 4) Wildlife experience with, and education about, other animal species are important factors in forming an appreciation for wildlife. 5) The practice of wildlife rehabilitation generates significant information about wildlife and medicine that is useful to discourse about wildlife. </p><p> This study will be relevant to professionals from other fields that work with wildlife and nonhuman animals: conservation, wildlife management, animal communication, and to the new field of trans-species psychology, among others. Captive environments and enrichment for education animals at WR centers could be used as models for captive animals in other industries: entertainment (zoos and circuses), as well as laboratory and research institutions. Finally, this theoretical analysis of WR, placed in the context of power relations, offers a significant contribution to human-centered studies such as those of human ethics (biomedical, especially, and around human test subjects), medicine and public health, and studies of social justice.</p>
8

Efficacy of an experiential, in-school educational program for improving elementary school students' attitudes and knowledge about the environment

Burger, Leslie M. 31 December 2014 (has links)
<p> Stagnant science achievement by students, greater demands and stresses on natural resources and environmental systems, and societal disengagement from nature highlight the need for education programs to ameliorate subsequent consequences. One attempt to address science performance and environmental apathy is Youth Environmental Science (YES), an environmental education program initiated in 2011 in a rural, minority-dominated, upper elementary school in Mississippi. The program provides five consecutive days (30 hours) of experiential learning in natural sciences. During 2011-2013, I studied cognitive and affective responses of fourth and fifth grade students to YES participation using a pretest-posttest-delayed posttest design. The influence of demographic factors (race/ethnicity, gender, and economic status) on student responses was also examined. </p><p> Compared to pretest scores, posttest knowledge and attitude scores were higher for YES participants, indicating the pedagogy was effective at promoting knowledge gains and positive environmental attitudes. Higher values were associated with female, non-Black, or higher income students; however, gains in both knowledge and attitude were similar across all demographic groupings, suggesting students from diverse backgrounds benefitted equally. Year-end proficiency exams indicated natural science knowledge gained by fourth and fifth grade students during their participation in YES did not decline with time, demonstrating retention and application of content knowledge. Moreover, although Black and low income fifth grade students had lower proficiency scores, these groups showed generally increasing trends in exam performance with elapsed time. This pattern suggests experiential and intensive environmental education interventions scheduled early in the academic year may be effective for sensitizing students for classroom learning that follows later in the year. This may be particularly impactful to those students who may experience fewer science enrichment and outdoor opportunities and thereby provide a mechanism for reducing achievement gaps among demographic groups.</p>
9

A Meta-Analysis of Successful Community-Based Payment for Ecosystem Services Programs

Pritzlaff, Richard G. 13 June 2018 (has links)
<p> Ecosystem services (ES), payments for ecosystem services (PES), and the development of markets for PES are transformational concepts and practices that emerged from environmental and ecological economics. Although the establishment of regulatory markets tends to be &ldquo;top down,&rdquo; there is evidence that more locally acceptable and successful markets tend to come from the community, from the &ldquo;bottom up.&rdquo; This meta-analysis analyzes 20 recent articles that examined approximately 454 PES cases from around the world, most organized from the bottom up. Cross-case analysis reveals possible best practices. Involving communities in design, decision-making, governance, and operation of local PES programs is found in many cases to contribute to improvements in both ecosystems and community livelihoods. Devolving project administration and ES provision monitoring to the local level is found to lower costs, increase project legitimacy, community equity, and leaves efficiency and fairness tradeoff decision-making in the hands of local communities. This in turn adds to feelings of competence, autonomy, and control. The experience of cooperative learning, skill acquisition, and enhanced individual and community capacities that results from participation in PES program design is found to positively influence social, cultural, economic, and multilevel political dynamics, allowing local sustainable resource use and management to emerge. In several cases, there are indications that this leads to a changed local and regional political economy due to successful value capture of enhanced ES resulting from restored ecosystems, as well as indications of other transformative changes in communities. These findings are used to provide recommendations to a watershed restoration initiative in the borderlands of Southern Arizona. </p><p>
10

Measuring and Developing Ecological Literacy to Conserve the Critically Endangered

Cook, Emily Louina 07 June 2018 (has links)
<p> The Mariana crow (<i>Corvus kubaryi</i>), locally and henceforth in this document called Aga, is a critically endangered species endemic to two Northern Mariana Islands. Aga are extirpated (locally extinct) on Guam but still persist on Rota. Multiple studies calculate a 93%&ndash;95% population decline over thirty years, with a recent estimate of 170 Aga on Rota. The primary reason for the decline on Rota is unknown, though predation by introduced mammals, habitat loss, and harassment are likely. The majority of research concerning Aga is in the biological sciences. The only social science survey conducted on Rota regarding Aga revealed that the majority of adult residents condone harassing Aga; yet, knowledge amongst Rota's inhabitants about bird ecology in general remains low, and youth residents were not surveyed. My study developed and implemented an avian-focused environmental education curriculum intended to increase ecological literacy, and evaluated the curriculum using social science research methods. My curriculum was based in storytelling, kinetic activities, and place-based education. I collaborated with local teachers to align the 5-lesson curriculum to science standards. Pre- and post-surveys were conducted with 18 control and 18 treatment students to gauge knowledge and attitudes in elementary students on Rota. Formative evaluations were also used to understand the preferred learning styles of students. Overall, students displayed some improvement in their avian ecological knowledge and positive attitudes towards Aga, and the treatment group improved in bird identification. Students in the treatment group increased their Aga identification by 38.8%. Notable for the treatment group, 23.5% of students thought it was okay to chase Aga in the pre-survey, yet 0% thought it was okay to in the post-survey. To save Aga from extinction, long-term environmental education initiatives are needed to raise ecological literacy, increase appreciation of these birds, and empower citizen science efforts on Rota.</p><p>

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