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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.
51

A case study analysis of curriculum implementation as exemplified by Project WILD in one Midwestern state /

Cantrell, Diane C. January 1987 (has links)
No description available.
52

Effects of mid-incubation egg movement on loggerhead (Caretta caretta) turtle hatch success and embryo development

Unknown Date (has links)
Due to an emergency status dune restoration project following Subtropical Storm Andrea in 2007 on Singer Island, Florida, nests needed to be moved during early to mid-incubation. Nesting success was compared between those moved mid-incubation, moved within 12h to either a native sand incubation area or a renourished sand incubation area, and those left in-situ. Nests moved within 12h to the native sand had a significantly larger proportion of pipped hatchlings. Nests moved mid-incubation had a significantly lower proportion of hatched eggs as well as emergent hatchlings. The stage in which embryonic development was arrested corresponded to the stage the embryos were in during the time of movement; indicating movement was the cause of death. When comparing nests moved within the initial 2.5 weeks of development to those moved after 2.5 weeks of development, there was no significant difference in hatching success. / by Natasha M. Ahles. / Vita. / Thesis (M.S.)--Florida Atlantic University, 2009. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2009. Mode of access: World Wide Web.
53

The economics of community-based wildlife conservation in Zimbabwe

Muchapondwa, Edwin. January 1900 (has links)
Thesis (Ph. D.)--Göteborg University, 2003. / Title from home page (viewed June 21, 2004). Added t.p. with thesis statement inserted. Includes bibliographical references. Also available in print.
54

Changing course| Repurposing golf landscapes for wildlife habitat and recreation

Yoder, Nicholas W. 19 February 2016 (has links)
<p> More than 1,400 golf facilities in the United States have closed permanently since 2001, part of a natural supply correction, as well as a reflection of the fluctuating interest in the game. Through their design, golf courses inherently preserve a singular form of open, green space. In their most dynamic form, they are culturally integral landscapes with vibrant ecosystems that provide wildlife habitat. They represent some of the largest &lsquo;undeveloped&rsquo; spaces in United States&rsquo; cities. Each golf course closing represents a single patch of many that, with sound design, could be woven together through a common purpose, like a landscape quilt. Through a site-specific analysis, the resulting design proposal for Wakefield Wildlife Reservation is a new type of landscape for the city of Westminster, MD, serving as an example for future projects. It will provide valuable habitat and dynamic recreational space, while expressing site and regional history.</p>
55

Stranding Mortality Patterns in California Sea Lions and Steller Sea Lions in Oregon and Southern Washington, 2006 to 2014

Lee, Kessina 09 July 2016 (has links)
<p> As changing ocean conditions lead to declining fish stocks and movement of forage fish, sea lions on the Oregon coast are subject to the pressures of declining prey availability and increasing conflicts with commercial and recreational fisheries. An analysis of strandings of California sea lions, <sub> Zalophus californianus,</sub> and Steller sea lions, <i>Eumetopias jubatus, </i> from 2006 to 2014, included cause of death, changing ocean conditions, and anthropogenic activity. Causes of death included disease, injury, and human interaction, such as gunshot wounds, fisheries net entanglements and boat strikes. </p><p> Oregon and Washington strandings of California sea lions are primarily adult and subadult males that migrate north from California rookeries, while Steller sea lions are year-round residents and strandings are comprised of males and females of all ages. While the California sea lion population is currently at or near carrying capacity, the Eastern Pacific population of Steller sea lions was designated as Threatened under the Endangered Species Act until October 2013. Understanding impacts to these two pinniped species is vital to implementing effective management and conservation policies.</p><p> Oregon and southern Washington strandings of California sea lions and Steller sea lions from 2006 to 2014 were analyzed spatially using the geographic information system (GIS), and temporally to identify possible correlations with prey availability and human interaction. Strandings were found to follow seasonal patterns from year to year: Steller sea lion strandings were highest from May to July, California sea lions peaked in September, October, and November. There was a correlation between significantly high numbers of strandings and the three largest commercial fisheries in Oregon: Chinook salmon, Coho salmon, and Dungeness crab. </p><p> This analysis provides a format for continuing to monitor primary ecological and anthropogenic drivers of pinniped mortality in Oregon and southern Washington. </p>
56

The movements, habitat use, and population assessment of western pond turtles (Actinemys marmorata) in a Southern California seasonal wetland

Nerhus, Barry S., Jr. 03 June 2016 (has links)
<p> This study investigates the population dynamics, movements, and habitat use of a population of western pond turtles in Orange County, California from 2008-2012 using radio telemetry and mark-recapture data. Western pond turtles have been thought to be declining throughout their range. However, few studies have documented their status in southern California, where urbanization has changed the landscape drastically in recent decades. I individually marked 236 pond turtles using hoop-net funnel traps and estimated the population size at 308 individuals, which is the largest estimate reported in southern California. Mean capture per unit effort was 5.03&plusmn;0.87. Mean female carapace length (CL) (142&plusmn;14mm) was not significantly larger than males (139&plusmn;14 mm). I also documented 20 nest and 9 estivation locations. Mean distances included 176 &plusmn;130.80 meters (m) and 91&plusmn;58.6 m. These data identify the population demography, which can be a metric of population stability. Other known populations need to be estimated to determine their regional status.</p>
57

Population Dynamics of Northern Cardinal and Carolina Wren in an Urban Forest Fragment| Safe Refuge or Ecological Trap?

Karmacharya, Binab 28 January 2016 (has links)
<p> Conserving bird populations in urban landscapes often depends on interactions between extinction, recolonization, and survival in remnant habitat patches such as small nature preserves. Thus, determining the ecological value of small nature preserves to birds is a necessary step towards an informed conservation strategy. As such, I conducted a year round capture-mark-recapture study from April 2010 to March 2014 to examine population dynamics of Northern Cardinals (<i>Cardinalis cardinalis</i>) and Carolina Wrens (<i> Thryothorus ludovicianus</i>) in a 41.7-ha nature preserve embedded in an urban matrix. More specifically, we examined variation in survival, recruitment, and realized population growth rates relative to year, season, sex, age, and wing length (as a proxy for body size) to investigate attributes that affect individual survival and to assess whether the reserve served as a population source or sink. The overall annual apparent survival rate of Northern Cardinals (0.520 &plusmn; SE 0.050) was higher than that of the Carolina Wrens (0.349 &plusmn; 0.050), and estimates in both species were similar to regional baseline estimates. The survival rates for adults were significantly higher than for immatures in both species, with body size having a positive influence on survival. Seasonal variation in survivorship was evident only in Northern Cardinals, being highest in the winter and lowest during the breeding season. Average annual population growth rate was slightly greater than 1.0 for both species, indicating stable or perhaps modestly increasing populations. These results represent the first published full annual cycle estimates of survival and population growth relative to age, sex, and body size for non-migratory passerines. Our results suggest that urban forests can provide the necessary resources to sustain growing populations of locally common birds. Furthermore, our demographic estimates derived from two healthy bird populations can serve as target values for other species of conservation concern within human-modified landscapes. </p>
58

Environmental drivers of deer population dynamics and spatial selection in southeast Alaska

Gilbert, Sophie L. 08 October 2015 (has links)
<p> The coastal temperate rainforest is one of the rarest ecosystems in the world, and a major portion of the global total is found in Southeast Alaska. In this ecosystem, Sitka black-tailed deer are the dominant large herbivore, influencing large carnivores that prey on deer such as wolves and bears, as well as plant species and communities through browsing. In addition, deer play an important economic and cultural role for humans in Southeast Alaska, making up the large majority of terrestrial subsistence protein harvested each year as well as providing the backbone of a thriving tourism industry built around sport hunting. Given the importance of deer in this system, there remain a surprisingly large number of key gaps in our knowledge of deer ecology in Southeast Alaska. </p><p> These knowledge gaps are potentially troubling in light of ongoing industrial timber-harvest across the region, which greatly alters habitat characteristics and value to wildlife. This dissertation research project was undertaken with the aim of filling several connected needs for further understanding deer ecology, specifically 1) patterns of reproduction and fawn survival, 2) population dynamics in response to environmental variability, and the underlying drivers of spatial selection during 3) reproduction and 4) winter. To fill these knowledge gaps, I developed robust statistical tools for estimating rates of fawn survival, and found that fawns must be captured at birth, rather than within several days of birth, in order to produce unbiased estimates because highly vulnerable individuals died quickly and were thus absent from the latter sample. I then use this robust approach to estimate vital rates, including fawn survival in winter and summer, and developed a model of population dynamics for deer. I found that winter weather had the strongest influence on population dynamics, via reduced over-winter fawn survival, with mass at birth and gender ratio of fawns important secondary drivers. </p><p> To better understand deer-habitat relationships, I examined both summer and winter habitat selection patterns by female deer. Using summer-only data, I asked how reproductive female deer balance wolf and bear predation risk against access to forage over time. Predation risks and forage were strong drivers of deer spatial selection during summer, but reproductive period and time within reproductive period determined deer reaction to these drivers. To ensure adequate reproductive habitat for deer, areas with low predation risk and high forage should be conserved. Focusing on winter, I evaluated deer spatial selection during winter as a response to snow depth, vegetation classes, forage, and landscape features. I allowed daily snow depth measures to interact with selection of other covariates, and found strong support for deer avoidance of deep snow, as well as changes in deer selection of old-growth and second-growth habitats and landscape features with increasing snow depth. Collectively, this dissertation greatly improves our understanding of deer ecology in Alaska, and suggests habitat management actions that will help ensure resilient deer populations in the future.</p>
59

The Grey Wolf : habitat suitability analysis of a top predator species over its global range

La Ville, Noemi di January 1998 (has links)
No description available.
60

The restoration of fluorspar tailings lagoons to amenity grassland

Burkinshaw, Stephanie Jane January 1998 (has links)
No description available.

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