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Quantifying The Impacts Of Oyster Reef Restoration On Oyster Coverage, Wave Attenuation And Seagrass Fragment Retention In Mosquito Lagoon, Florida, Stephanie Garvis Jan 2012

Quantifying The Impacts Of Oyster Reef Restoration On Oyster Coverage, Wave Attenuation And Seagrass Fragment Retention In Mosquito Lagoon, Florida, Stephanie Garvis

Electronic Theses and Dissertations

The goal of this project was to determine the effects of oyster reef restoration on oyster coverage, wave height dissipation and seagrass recruitment. First, to assess the current versus historical coverage of natural, dead and restored oyster reefs within Mosquito Lagoon, aerial photographs from 2009, provided by Saint Johns River Water Management District, were digitized using ArcGIS software. Live reefs, restored reefs and dead reefs were screen digitized using a reef ‘signature’ in order to estimate the area of each type of reef. The 2009 maps were used as a guide to digitizing the historical aerial photographs (1943, 1951, 1967, …


Livelihoods Support Programs, Conservation Attitudes, And Tropical Biodiversity: An Evaluation Of Biocomplexity In Southeastern Ghana, Edem Kodzo Ekpe Jan 2012

Livelihoods Support Programs, Conservation Attitudes, And Tropical Biodiversity: An Evaluation Of Biocomplexity In Southeastern Ghana, Edem Kodzo Ekpe

Electronic Theses and Dissertations

Human activities are a major driver of biodiversity degradation and loss, especially in tropical forest areas, where forest-fringe towns and villages depend on the forests for their livelihoods. In order to reduce threats that human activities pose to biodiversity, livelihoods support programs are employed as economic incentives for biodiversity conservation. These programs support the livelihoods activities of local communities, with the aim of triggering favorable attitudes and behaviors towards conservation, and ultimately reduce biodiversity degradation. Their effectiveness as conservation tools has not been evaluated. I investigated the effects of livelihoods programs on conservation attitudes and the consequent effects on biodiversity …


Dispersal, Gene Flow, And Adaptive Evolution During Invasion: Testing Range-Limit Theory With The Asian Tiger Mosquito, Kimberly Medley Jan 2012

Dispersal, Gene Flow, And Adaptive Evolution During Invasion: Testing Range-Limit Theory With The Asian Tiger Mosquito, Kimberly Medley

Electronic Theses and Dissertations

Understanding the factors that make non-native species successful invaders is an important step towards mitigating spread. At the same time, species invasions can serve as natural experiments to test range-limit theory. Range-limit theory postulates declines in local abundance (abundant center model) and genetic diversity (central-peripheral hypothesis) towards range edges because of underlying environmental gradients. Such declines constrain adaptation to marginal habitats via gene swamping. However, broader evolutionary theory predicts intermediate rates of immigration into range-edge populations can relieve genetic drift and improve adaptive potential. I tested hypotheses generated from theory while illuminating aspects affecting of the invasion of the Asian …


Effect Of Predation Risk And Food Availability On Parental Care And Nest Survival In Suburban And Wildland Florida Scrub-Jays, Joseph M. Niederhauser Jan 2012

Effect Of Predation Risk And Food Availability On Parental Care And Nest Survival In Suburban And Wildland Florida Scrub-Jays, Joseph M. Niederhauser

Electronic Theses and Dissertations

Individual organisms often use cues from their natural environments to determine many behavioral and life-history "decisions." These "decisions" are usually adaptive, i.e. a response to selection, because the environmental cues on which they are based reliably correlate with increased fitness over time. When the selected behavioral response to a natural cue no longer provides a fitness benefit, then selection for a new response may occur but individuals maintaining the previously selected response may suffer reduced survival and reproduction. Especially in human-modified landscapes individuals making a maladaptive behavioral or life-history choice based on those formerly reliable environmental cues may be faced …


Phylogenetic Community Structure Of Aquatic Beetle Assemblages In A Multi-Wetland Experiment, Sandor Lawrence Kelly Jan 2012

Phylogenetic Community Structure Of Aquatic Beetle Assemblages In A Multi-Wetland Experiment, Sandor Lawrence Kelly

Electronic Theses and Dissertations

Phylogenetic Community Structure (PCS) metrics are becoming more common in community ecology. PCS metrics estimate the phylogenetic relatedness among members of an ecological community or assemblage. If ecological traits are conserved, then phylogenetic clustering (i.e., taxa are more closely related than expected by chance) indicates habitat filtering as the key process in community assembly. On the other hand, a pattern of phylogenetic overdispersion (i.e., taxa are more distantly related than expected by chance) suggests competition is dominant. Most studies to date have used PCS of unmanipulated ecosystems, but the value of PCS metrics will be best revealed in experiments. This …


Factors Limiting Native Species Establishment On Former Agricultural Lands, Annalisa M. Weiler-Lazarz Jan 2012

Factors Limiting Native Species Establishment On Former Agricultural Lands, Annalisa M. Weiler-Lazarz

Electronic Theses and Dissertations

Restoration of abandoned, nonnative species-dominated agricultural lands provides opportunities for conserving declining shrubland and grassland ecosystems. Land-use legacies, such as elevated soil fertility and pH from agricultural amendments, often persist for years and can favor nonnative species at the expense of native species. Understanding the factors that limit native species establishment on abandoned agricultural lands can provide important insights for restoration and conservation of native species on human-modified lands. I conducted two field experiments on abandoned agricultural lands: a former pasture on Martha’s Vineyard, MA and a former citrus grove at Merritt Island National Wildlife Refuge (MINWR) in Titusville, FL. …


Landscaping Perceptions And Behaviors: Socio-Ecological Drivers Of Nitrogen In The Residential Landscape, Leesa Souto Jan 2012

Landscaping Perceptions And Behaviors: Socio-Ecological Drivers Of Nitrogen In The Residential Landscape, Leesa Souto

Electronic Theses and Dissertations

Driven by individual influences such as beliefs, attitudes, personal norms, and abilities, as well as by social influences like community norms, mandates, and the market, suburban homeowners are motivated to select and maintain a turf grass landscape. In many areas of Florida, effective suburban lawn maintenance requires regular inputs of nitrogenous fertilizer, some of which is lost to the environment, contributing to water quality degradation and ecosystem dysfunction. Reducing nitrogen inputs to aquatic systems requires a better understanding of the links between residential landscape management and the potential for fertilizer loss. This dissertation examines the linkages between the human behaviors …


Biochemical Studies Of Abce1, Lynn Sims Jan 2012

Biochemical Studies Of Abce1, Lynn Sims

Electronic Theses and Dissertations

The growth and survival of all cells require functional ribosomes that are capable of protein synthesis. The disruption of the steps required for the function of ribosomes represents a potential future target for pharmacological anti-cancer therapy. ABCE1 is an essential Fe-S protein involved in ribosomal function and is vital for protein synthesis and cell survival. Thus, ABCE1 is potentially a great therapeutic target for cancer treatment. Previously, cell biological, genetic, and structural studies uncovered the general importance of ABCE1, although the exact function of the Fe-S clusters was previously unclear, only a simple structural role was suggested. Additionally, due to …


Species And Habitat Interactions Of The Gopher Tortoise: A Keystone Species?, Christopher Catano Jan 2012

Species And Habitat Interactions Of The Gopher Tortoise: A Keystone Species?, Christopher Catano

Electronic Theses and Dissertations

Species-species and species-habitat interactions have been demonstrated to be important in influencing diversity across a variety of ecosystems. Despite generalities in the importance of these interactions, appropriate mechanisms to explain them are absent in many systems. In sandhill systems of the southeast U.S., gopher tortoises have been hypothesized to be a crucial species in the maintenance of diversity and function. However, the mechanisms and magnitude in which they influence their communities and habitats have rarely been empirically quantified. I examined how habitat structure influences tortoise abandonment of burrows and how tortoise densities influence nonvolant vertebrate community diversity. Tortoise burrow abandonment …


Relating Ancient Maya Land Use Legacies To The Contemporary Forest Of Caracol, Belize, Jessica N. Hightower Jan 2012

Relating Ancient Maya Land Use Legacies To The Contemporary Forest Of Caracol, Belize, Jessica N. Hightower

Electronic Theses and Dissertations

Human land use legacies have significant and long lasting impacts across landscapes. However, investigating the impacts of ancient land use legacies ( > 400 years) remains problematic due to the difficulty in detecting ancient land uses, especially those beneath dense canopies. The city of Caracol, one of the most important Maya archaeological sites in Belize, was abandoned after the collapse of the Maya civilization (ca. A.D. 900), leaving behind numerous structures, causeways, and agricultural terraces that persist beneath the dense tropical forest of western Belize. LiDAR (Light Detection and Ranging) technology enables detection of below canopy Maya archaeological features, providing an …


Life History Response To Infection And The Potential For Dishonest Signals In The Ground Cricket, Allonemobius Socius, Emily Copeland Jan 2012

Life History Response To Infection And The Potential For Dishonest Signals In The Ground Cricket, Allonemobius Socius, Emily Copeland

Electronic Theses and Dissertations

In order to maximize fitness, individuals must partition their limited resources among competing physiological processes, creating negative statistical associations between processes known as “life-history trade-offs”. Evidence indicates that individuals tend to decrease their reproductive investment when confronted with a significant immunological challenge in order to increase investment in immune defense. This trade-off is often accompanied by a significant decrease in the sexual signal, which provides an honest signal of the male’s infection status to potential mates. However, if individual residual reproductive value is low, they may instead increase their reproductive investment to maximize reproductive success before the end of their …


The Next "Killer" Algae? Assessing And Mitigating Invasion Risk For Aquarium Strains Of The Marine Macroalgal Genus Chaetomorpha, Rachel Odom Jan 2012

The Next "Killer" Algae? Assessing And Mitigating Invasion Risk For Aquarium Strains Of The Marine Macroalgal Genus Chaetomorpha, Rachel Odom

Electronic Theses and Dissertations

Biological invasions threaten the ecological integrity of natural ecosystems. Anthropogenic introductions of non-native species can displace native flora and fauna, altering community compositions and disrupting ecosystem services. One often-overlooked vector for such introductions is the release of aquarium organisms into aquatic ecosystems. Following detrimental aquarium-release invasions by the "killer alga" Caulerpa taxifolia, aquarium hobbyists and professions began promoting the use of other genera of macroalgae as "safe" alternatives. The most popular of these marine aquarium macroalgae, the genus Chaetomorpha, is analyzed here for invasion risk. Mitigation strategies are also evaluated. I found that the propensity for reproduction by vegetative fragmentation …


Conservation And Population Biology: Genetics, Demography And Habitat Requirements Of The Atlantic Coast Beach Mice, Haakon Myklevoll Kalkvik Jan 2012

Conservation And Population Biology: Genetics, Demography And Habitat Requirements Of The Atlantic Coast Beach Mice, Haakon Myklevoll Kalkvik

Electronic Theses and Dissertations

The conservation biology field seeks to preserve biodiversity and the processes shaping that variation. Conservation biology is intimately tied to evolutionary research, in order to identify evolutionary distinct lineages that may be in danger of disappearing. Interestingly, patterns and processes of lineage divergence and persistence change with respect to spatial and temporal scale. I seek to evaluate biodiversity, the factors that have shaped this heterogeneity, and how this variability persists. To accomplish this I used a phylogeographic approach as well as niche and population modeling on the Peromyscus maniculatus species group found widely distributed in North America. My emphasis was …


Beyond Building A Tree: Phylogeny Of Pitvipers And Exploration Of Evolutionary Patterns, Allyson Fenwick Jan 2012

Beyond Building A Tree: Phylogeny Of Pitvipers And Exploration Of Evolutionary Patterns, Allyson Fenwick

Electronic Theses and Dissertations

As generic and higher-scale evolutionary relationships are increasingly well understood, systematists move research in two directions: 1) understanding specieslevel relationships with dense taxon sampling, and 2) evaluating evolutionary patterns using phylogeny. In this study I address both foci of systematic research using pitvipers, subfamily Crotalinae. For direction one, I evaluate the relationships of 96% of pitvipers by combining independent sets of molecular and phenotypic data. I find the inclusion of species with low numbers of informative characters (i.e. less than 100) negatively impacts resolution of the phylogeny, and the addition of independent datasets has no effect on or a small …


Determining The Impacts Of Beach Restoration On Loggerhead (Caretta Caretta) And Green Turtle (Chelonia Mydas) Nesting Patterns And Reproductive Success Along Florida's Atlantic Coast, Allison Whitney Hays Jan 2012

Determining The Impacts Of Beach Restoration On Loggerhead (Caretta Caretta) And Green Turtle (Chelonia Mydas) Nesting Patterns And Reproductive Success Along Florida's Atlantic Coast, Allison Whitney Hays

Electronic Theses and Dissertations

Artificial beach nourishment, the most common method to mitigate coastal erosion in the United States, is also considered the most ecologically friendly alternative for shoreline stabilization. However, this habitat alteration has the potential to impact nesting marine turtles and developing hatchlings. The first objective of this study was to determine how nourishing beaches with two different design templates affects loggerhead (Caretta caretta) and green turtle (Chelonia mydas) nesting success, the ratio of nests to the total number of nests and non-nesting emergences, and reproductive success, the ratio of hatched and emerged hatchlings to the total number of eggs deposited. Two …


Genetic Interactions Between The Guanine Nucleotide Exchange Factor Gefmeso And Gtpase Signaling Components In The Drosophila Wing Reveal Microenvironment Dependent Variation Within Gtpase Signaling N, Ashley Megan Iketani Jan 2012

Genetic Interactions Between The Guanine Nucleotide Exchange Factor Gefmeso And Gtpase Signaling Components In The Drosophila Wing Reveal Microenvironment Dependent Variation Within Gtpase Signaling N, Ashley Megan Iketani

Electronic Theses and Dissertations

The Ras superfamily of GTPases are important regulators of morphogenesis involved in control of cytoskeletal dynamics, intracellular trafficking, apical-basal polarity and cell migration. Mis-regulation of GTPase signaling interferes with development and is linked to pathogenesis. Traditionally, GTPase signaling has been depicted as a series of independent linear pathways. However, recently it has become apparent that multiple GTPases can interact to regulate a single cellular process, functioning in poorly understood networks of cross talk between pathways during development. Jim Fristrom (unpublished data) identified a mutation (18-5) that interacts with components of the GTPases Rho1, Rala, and Cdc42 signaling in multiple developmental …


Fine-Scale Geographic Variation Of Stable Isotope And Fatty Acid Signatures Of Three Fish Species In The Indian River Lagoon, Fl, Jennifer Fletcher Odom Jan 2012

Fine-Scale Geographic Variation Of Stable Isotope And Fatty Acid Signatures Of Three Fish Species In The Indian River Lagoon, Fl, Jennifer Fletcher Odom

Electronic Theses and Dissertations

The Indian River Lagoon, Florida, is a unique closed “bar built” estuary system that has little interchange with the Atlantic Ocean and which is home to many resident species. Three fish species were investigated to see if their isotopic and fatty acid signatures differed based on geographic location. The goal was to assess the degree of resolution of spatial variation that is possible when using stable isotope and fatty acid signature analysis to interpret feeding habits and potential linkages between feeding habits and health status. Spotted seatrout (n=40), pinfish (n=60) and white mullet (n=60) were collected over a 4 week …