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The Effects Of Non-Native Species On Two Life-Stages Of The Eastern Oyster Crassostrea Virginica, Wei Yuan Jan 2014

The Effects Of Non-Native Species On Two Life-Stages Of The Eastern Oyster Crassostrea Virginica, Wei Yuan

Electronic Theses and Dissertations

Since their recent introductions into Florida waters, three nonnative species [Perna viridis Linnaeus, 1758 (Asian green mussel), Mytella charruana d'Orbigny, 1846 (charru mussel) and Megabalanus coccopoma Darwin, 1854 (pink titan acorn barnacle)] have expanded both north and south along the Atlantic coast. Very little research has been done to understand how these nonnative species interact with the native eastern oyster (Crassostrea virginica Gmelin, 1791), which is a keystone species that provides important ecological services and economic benefits. To test the potential effects of P. viridis, M. charruana and M. coccopoma on C. virginica, I addressed the following questions: 1a) Does …


Migratory Connectivity And Carry-Over Effects In Northwest Atlantic Loggerhead Turtles (Caretta Caretta, L.), Simona Ceriani Jan 2014

Migratory Connectivity And Carry-Over Effects In Northwest Atlantic Loggerhead Turtles (Caretta Caretta, L.), Simona Ceriani

Electronic Theses and Dissertations

Migration is a widespread and complex phenomenon in nature that has fascinated humans for centuries. Connectivity among populations influences their demographics, genetic structure and response to environmental change. Here, I used the loggerhead turtle (Caretta caretta, L.) as a study organism to address questions related to migratory connectivity and carry-over effects using satellite telemetry, stable isotope analysis and GIS interpolation methods. Telemetry identified foraging areas previously overlooked for loggerheads nesting in Florida. Next, I validated and evaluated the efficacy of intrinsic markers as a complementary and low cost tool to assign loggerhead foraging regions in the Northwest Atlantic Ocean (NWA), …


Physiological Constraints On Warm-Water Habitat Site Selection And Utilization By The Florida Manatee (Trichechus Manatus Latirostris) In East Central Florida, Ann Spellman Jan 2014

Physiological Constraints On Warm-Water Habitat Site Selection And Utilization By The Florida Manatee (Trichechus Manatus Latirostris) In East Central Florida, Ann Spellman

Electronic Theses and Dissertations

Living at the northern limits of its geographic range, the Florida manatee is particularly susceptible to cold stress-related mortality during the winter months, with most deaths occurring in the lower two-thirds of the state. Contributing to this cold stress susceptibility is the manatee's limited physiological and behavioral responses available when thermally stressed. While capable of migrating south in response to falling water temperatures, manatees must still find warm water when ambient river temperature drops below 20°C for more than a few days. This is in part due to the species low metabolic rate, limited capacity for thermogenesis, and limited ability …


Effects Of Mechanical Habitat Disturbance On The Diversity And Network Structure Of Plant-Bee Interaction Networks In Central Florida, Karlie Carman Jan 2014

Effects Of Mechanical Habitat Disturbance On The Diversity And Network Structure Of Plant-Bee Interaction Networks In Central Florida, Karlie Carman

Electronic Theses and Dissertations

Ecological interactions within a community shape the structure of ecosystems and influence ecosystem function. Plant-pollinator interactions exist as mutualistic exchange networks that may collapse as habitat loss occurs, thereby threatening the overall health of an ecosystem. Understanding the impacts of human-mediated habitat disturbance on ecological interactions is therefore crucial for conservation efforts. Archbold Biological Station (ABS) in Venus, Florida contains over 2000 hectares of protected Florida scrub habitat nested within a human-dominated environment that is threatened by anthropogenic habitat disturbance. In past studies, over 113 bee species and 157 associated host plants, many endemic to the Lake Wales Ridge, have …


Evaluation Of The Three-Dimensional Patterns And Ecological Impacts Of The Invasive Old World Climbing Fern (Lygodium Microphyllum), Alexis Maldonado Jan 2014

Evaluation Of The Three-Dimensional Patterns And Ecological Impacts Of The Invasive Old World Climbing Fern (Lygodium Microphyllum), Alexis Maldonado

Electronic Theses and Dissertations

Invasion by non-native species has had significant ecological and economic impacts on a global scale. In the state of Florida, Old World climbing fern (Lygodium microphyllum) is an invasive plant listed by FLEPPC as a category one invader with significant ecological impacts that threaten native plant diversity. This species relies on existing vegetative structures for support to climb into the forest canopy and forms dense mats that cover tree crowns. This subsequently affects the resources available to other species present. Quantifying the structural changes due to the presence of this species has proved logistically difficult, especially on a large spatial …


Movements, Fishery Interactions, And Unusual Mortalities Of Bottlenose Dolphins, Steven Shippee Jan 2014

Movements, Fishery Interactions, And Unusual Mortalities Of Bottlenose Dolphins, Steven Shippee

Electronic Theses and Dissertations

Bottlenose dolphins inhabiting coastlines and estuaries in Florida have been impacted in the past decade by development, algal blooms, catastrophic pollution, and fishery interactions (FI). Dolphins react to disturbance and environmental stressors by modifying their movements and habitat use, which may put them in jeopardy of conflict with humans. FI plays an increasing role in contributing to dolphin mortalities. I investigated dolphin movements, habitat use, residency patterns, and frequency of FI with sport fishing. Tagging studies with short-term data tags and bolt on radio-transmitters were done in several locations in Florida and the east coast providing fine-scale measurements of swimming, …


Character Evolution And Microbial Community Structure In A Host-Associated Grasshopper, Tyler Raszick Jan 2014

Character Evolution And Microbial Community Structure In A Host-Associated Grasshopper, Tyler Raszick

Electronic Theses and Dissertations

The spotted bird grasshopper, Schistocerca lineata Scudder (Orthoptera: Acrididae), is a widely distributed species found throughout most of the continental United States and southern Canada. This species is known to be highly variable in morphology, with many distinct ecotypes across its native range. These ecotypes display high levels of association with type-specific host plants. Understanding the evolutionary relationships among different ecotypes is crucial groundwork for studying the process of ecological differentiation. I examine four ecotypes from morphological and phylogeographic perspectives, and look for evidence of distinct evolutionary lineages within the species. I also begin to explore the potential role of …


Juvenile Ornamentation: Its Evolution, Genetic Basis, And Variation Across Habitats, Angela Tringali Jan 2013

Juvenile Ornamentation: Its Evolution, Genetic Basis, And Variation Across Habitats, Angela Tringali

Electronic Theses and Dissertations

Ornamental traits are considered honest advertisements of fitness, and their evolution is usually explained in terms of sexual selection. This explanation remains unsatisfactory in some instances, for example, juvenile birds whose plumage is molted prior to adulthood and breeding. I first evaluate whether juvenile plumage reflectance signals dominance status in the Federally Threatened Florida scrub-jay (Aphelocoma coerulescens) using a combination of observational and experimental methods. Then I estimate the heritability, non-genetic maternal and environmental effects, and strength of selection on juvenile plumage reflectance using archived feather samples and a pedigree constructed from historical nest records. Finally, I compare plumage reflectance …


Wetland Diversity In A Disturbance-Maintained Landscape: Effects Of Fire And A Fire Surrogate On Aquatic Amphibian Survival And Species Depauperateness., Joyce Klaus Jan 2013

Wetland Diversity In A Disturbance-Maintained Landscape: Effects Of Fire And A Fire Surrogate On Aquatic Amphibian Survival And Species Depauperateness., Joyce Klaus

Electronic Theses and Dissertations

Disturbance is one of the central concepts explaining how diversity arises and is perpetuated in ecological time. A good model system for testing hypotheses related to disturbance is the longleaf pine ecosystem in the southeastern U.S. because in this ecosystem frequent, low-severity fires acts as a disturbance that maintains a unique vegetation structure and high species richness. Vegetation structure influences animal distributions; in fire-dependent ecosystems many animals rely on open-structured, fire-maintained vegetation but shrubs and trees encroach into fire-dependent ecosystems where fire has been excluded. Prescribed burning and mechanical removal are commonly used as restoration tools to control encroachment. To …


Testing For Indirect Benefits Of Polyandry In The Florida Green Turtle, Christopher Long Jan 2013

Testing For Indirect Benefits Of Polyandry In The Florida Green Turtle, Christopher Long

Electronic Theses and Dissertations

Behavioral studies in the green turtle (Chelonia mydas) have indicated that promiscuous mating is commonplace. Though it has been shown that there is much variation in the rate of polyandry (females mating with multiple males), the drivers behind polyandry in this species are unknown. It has been speculated, but never demonstrated, that indirect benefits (fitness benefits resulting from offspring genetic diversity) play a role. However, previous tests of this hypothesis have limited scope of inference due to lack of environmental control. In this thesis, I attempted to study the indirect benefits of polyandry in Archie Carr National Wildlife Refuge (ACNWR) …


Florida Local Government Conservation Planning: Variability, Drivers, And Policy Implications, Pamela Pannozzo Jan 2013

Florida Local Government Conservation Planning: Variability, Drivers, And Policy Implications, Pamela Pannozzo

Electronic Theses and Dissertations

This study examined the quality of Florida county government conservation planning. To assess conservation planning quality, a theoretical model of conservation planning as prescribed by the conservation science literature was first developed. A plan evaluation coding protocol was applied to local comprehensive plan Conservation Elements to determine the extent to which county-level conservation planning met the theoretical model. A high degree of variability in conservation planning quality was found. Highest quality conservation planning occurred in the Gulf coast counties of southwest Florida. Lowest conservation planning quality occurred in the Florida Panhandle counties. The quality of conservation planning of coastal counties …


Relating Climate Change To The Nesting Phenology And Nest Environment Of Marine Turtles, Monette Schwoerer Jan 2013

Relating Climate Change To The Nesting Phenology And Nest Environment Of Marine Turtles, Monette Schwoerer

Electronic Theses and Dissertations

Ectotherms (including marine turtles) being especially sensitive to climate, are at risk to the accelerated rate of human-driven climate change. This study addresses two concerns associated with marine turtles and climate change – the relationship between the timing of marine turtle nesting and sea surface temperature; and the concern over the feminization of marine turtle populations due to rising sand temperatures. Previous studies of loggerhead sea turtles (Caretta caretta) and green sea turtles (Chelonia mydas) have documented the relationship between sea surface temperatures and nesting phenology. Earlier nesting behaviors in both species have been associated with warmer sea surface temperatures. …


Assessing The Effectiveness Of Living Shoreline Restoration And Quantifying Wave Attenuation In Mosquito Lagoon, Florida, Jennifer Manis Jan 2013

Assessing The Effectiveness Of Living Shoreline Restoration And Quantifying Wave Attenuation In Mosquito Lagoon, Florida, Jennifer Manis

Electronic Theses and Dissertations

Coastal counties make up only 17% of the land area in the continental United States, yet 53% of the nation’s population resides in these locations. With sea level rise, erosion, and human disturbances all effecting coastal areas, researchers are working to find strategies to protect and stabilize current and future shorelines. In order to maintain shoreline stability while maintaining intertidal habitat, multipurpose living shorelines have been developed to mimic natural shoreline assemblages while preventing erosion. This project determined the effectiveness of a living shoreline stabilization containing Crassostrea virginica (eastern oyster) and Spartina alterniflora (smooth cordgrass) in the field and through …


Sex Ratios Of Juvenile Green Turtles (Chelonia Mydas) In Three Developmental Habitats Along The Coast Of Florida, Cheryl Sanchez Jan 2013

Sex Ratios Of Juvenile Green Turtles (Chelonia Mydas) In Three Developmental Habitats Along The Coast Of Florida, Cheryl Sanchez

Electronic Theses and Dissertations

The concept of temperature dependent sex determination (TSD) has been somewhat of an evolutionary enigma for many decades and has had increased attention with the growing predictions of a changing climate, particularly in species that are already threatened or endangered. TSD taxa of concern include marine turtles, which go through various life stages covering a range of regions. This, in turn, creates difficulties in addressing basic demographic questions. Secondary sex ratios (from life stages post-hatchling) were investigated by capturing juvenile green turtles (Chelonia mydas), 22.6-60.9 cm in straight carapace length (SCL), from three developmental areas along the east coast of …


Population Dynamics And Environmental Factors Influencing Herbs In Intact And Degraded Florida Rosemary Scrub, Elizabeth Stephens Jan 2013

Population Dynamics And Environmental Factors Influencing Herbs In Intact And Degraded Florida Rosemary Scrub, Elizabeth Stephens

Electronic Theses and Dissertations

Species have complex and contextual relationships with their environment; both the relative contributions of life-history stages to population growth and the effect of environmental factors on each stage can be different among co-existing species. Timing and extent of reproduction, survival, and mortality determine population growth, species distributions, and assemblage patterns. I evaluate the role of habitat (intact, degraded) and microsite (shrub, leaf litter, bare sand) on population dynamics of Florida scrub herbs. Isolated overgrown shrubs and extensive bare sand areas in degraded scrub were expected to decrease seed predation, reduce competition of herbs with shrubs, and provide larger habitat for …


Modeling Survival Of Immature Loggerheads (Caretta Caretta) And Green Turtles (Chelonia Mydas) From 10 Years Of Mark-Recapture Data At The Florida Power And Light St. Lucie Plant, Andrew Sterner Jan 2013

Modeling Survival Of Immature Loggerheads (Caretta Caretta) And Green Turtles (Chelonia Mydas) From 10 Years Of Mark-Recapture Data At The Florida Power And Light St. Lucie Plant, Andrew Sterner

Electronic Theses and Dissertations

Loggerheads (Caretta caretta) are listed as Threatened and green turtles (Chelonia mydas) are listed as Endangered under the United States Endangered Species Act. While green turtle nest production in Florida has increased markedly in recent years, loggerhead nest production has followed a more tenuous path. Reasons for these differences are unknown. Limited demographic information is available for these species of conservation concern. I used Barker models, which incorporated mark-recapture, live-resight and dead recovery data, implemented in Program MARK. These models were used to estimate apparent survival for immature loggerhead (


Disturbance-Based Management And Plant Species Change In Massachusetts Sandplain Heathlands Over The Past Two Decades, Kirsten Martin Jan 2013

Disturbance-Based Management And Plant Species Change In Massachusetts Sandplain Heathlands Over The Past Two Decades, Kirsten Martin

Electronic Theses and Dissertations

Massachusetts sandplain heathlands are habitats of conservation concern, harboring many rare plant species and providing habitat for animals that depend on openlands. These heathlands are threatened by human development, shrub encroachment in the absence of disturbance, and potentially increasing soil nutrient levels. Sandplain heathlands are managed with prescribed fire, in order to maintain their open structure and maintain species diversity. In order to assess how past management was correlated with species change, I used a data set that spanned twenty years from three different heathlands in Massachusetts. I looked for correlations between management and species change. Correlations between species change …


Habitat Use And Feeding Ecology Of Delphinids Inferred From Stable Isotopes And Fatty Acid Signatures, Nicole Browning Jan 2013

Habitat Use And Feeding Ecology Of Delphinids Inferred From Stable Isotopes And Fatty Acid Signatures, Nicole Browning

Electronic Theses and Dissertations

Prey availability, directly or indirectly, affects all aspects of a predator’s life history and is a primary factor influencing habitat selection and movements. This is especially true for delphinid species where it has been documented that the behaviors and movements of dolphins are strongly influenced by food availability. Unfortunately, the feeding ecology and habitat use patterns of many of these species are poorly understood. Many methodologies that have been employed to explore these facets of dolphin ecology have limitations and constraints or are logistically infeasible. Stable isotope and fatty acid signature analyses have been used extensively on a wide variety …


Estimated Diets, Diet Overlap, And Winter Habitat Associations Of Four Grassland Sparrows In Florida Dry Prairie, Marianne Korosy Jan 2013

Estimated Diets, Diet Overlap, And Winter Habitat Associations Of Four Grassland Sparrows In Florida Dry Prairie, Marianne Korosy

Electronic Theses and Dissertations

North American grassland birds show long-term population declines that generally exceed the declines of other bird groups. Efforts to conserve grassland birds require knowledge of diet and habitat requirements during both the breeding and nonbreeding periods of annual life cycles. This dissertation investigated sparrow habitat associations within two defined plant communities of the dry prairie ecosystem, the dry-mesic and wet-mesic prairie, for four prescribed fire treatments over two consecutive winters. Grasshopper and Henslow’s sparrows showed higher relative abundance in wet-mesic prairie and Bachman’s Sparrows were more abundant in dry-mesic prairie across all fire treatments. Abundances of Grasshopper and Bachman’s sparrows …


Biogeography And Systematics Of The Nerodia Clarkii/Nerodia Fasciata Clade In Florida, Gregory Territo Jan 2013

Biogeography And Systematics Of The Nerodia Clarkii/Nerodia Fasciata Clade In Florida, Gregory Territo

Electronic Theses and Dissertations

Biogeography provides a window into the evolutionary history of populations, and helps explain the diversity and distribution of life through time. Viewed from a systematic perspective, biogeographic studies generate convincing arguments to explain the relationships among organisms and categorize them into useful taxonomies. When taxonomies do not reflect evolutionary histories, inaccurate representations of biodiversity confound future studies and conservation efforts. Two thamnophiine snakes, Nerodia clarkii and Nerodia fasciata, harbor unique morphological and ecological adaptations that obscured natural groupings, leading to controversial taxonomic delimitations. Additionally, population declines documented in N. clarkii compressicauda and N. clarkii taeniata led managers to list N. …


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 …