Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 13 of 13
Full-Text Articles in Entire DC Network
Pine, Aphids, And Parasitoid Wasps: Patterns Of Cospeciation And Host Switches In A Tri-Trophic System, Amber Bass
Pine, Aphids, And Parasitoid Wasps: Patterns Of Cospeciation And Host Switches In A Tri-Trophic System, Amber Bass
Electronic Theses and Dissertations
Ecological interactions may drive speciation events, and the processes that drive these speciation events can leave behind patterns in the phylogenies of interacting taxa. These patterns have been studied extensively in herbivores and host plants, as well as parasites and their hosts, but rarely in tri-trophic systems. Here, we examine three closely related groups of interacting taxa, including parasitoid wasps (Pauesia), aphid herbivores (Cinara), and pine trees (Pinus) to determine if the patterns between each interacting taxa indicate that cospeciation or host switches are more dominant. We create phylogenies of Cinara and Pauesia in the southeastern United States using ddRADseq …
Do Per-Capita Impact Or Abundance Dominate The Impact Of An Invader? Interactions Among Neighboring Species In Context-Dependent Competition, Haoyu Li
Electronic Theses and Dissertations
Evaluating relative species competitive strength is a central question in community ecology, with strong implications for invasion ecology. Models assessing invader success consider three components: distribution, abundance and per-capita impact. However, relative strength and interactions among these factors remain unclear when applying to specific invasion scenarios. We hypothesized that performance of native and non-native species will vary as a function of direct and indirect effects at different abundances and scales. We conducted a replacement experiment between two dominant grasses in subtropical grasslands (the native Axonopus fissifolius and the non-native Paspalum notatum) in central Florida, USA. Thirty fenced plots (1 m …
Biogeochemical Effects Of Sea Level Rise-Induced Transitions Within Coastal Wetlands, Havalend Steinmuller
Biogeochemical Effects Of Sea Level Rise-Induced Transitions Within Coastal Wetlands, Havalend Steinmuller
Electronic Theses and Dissertations
As sea level rise (SLR) affects coastal wetlands, ecosystem responses can include vertical accretion, landward transgression, or submergence. Sea level rise-induced transitions can alter key biogeochemical transformations within wetland soils, impacting the ability of these systems to provide ecosystem services, specifically carbon (C) storage and water quality regulation. Through a series of complementary laboratory and field-based studies, biogeochemical responses to salinity, vegetation shifts, and submergence were investigated. Changes in nutrient dynamics associated with saltwater intrusion were evaluated by artificially adding saline water to different freshwater wetland soil types, indicating that potential exports of critical nutrients (forms of nitrogen, phosphorus, and …
Exploring Multi-Scale Variation Of Fish Community Diversity In A Dynamic Coastal Estuary, Brittany Troast
Exploring Multi-Scale Variation Of Fish Community Diversity In A Dynamic Coastal Estuary, Brittany Troast
Electronic Theses and Dissertations
Examining diversity over multiple spatial and temporal scales affords the opportunity to develop a mechanistic understanding of the factors influencing community diversity dynamics, and how these may shift in a changing world. This thesis first examines multi-decadal fish community diversity metrics across a coastal biogeographic transition zone to quantify changes in species assemblages, assess relationships between fish community diversity and the abiotic environment, and capture potential shifts in the location of a putative biogeographic break. Results of this chapter indicate not only a change in fish community composition, but also a shift in the location of the biogeographic transition zone. …
Assessing The Effects Of Habitat And Manatee Exclusion Devices On Red Drum (Sciaenops Ocellatus) Movement Patterns In Estuarine Impoundments, Steven Baker
Electronic Theses and Dissertations
The Integrate-Transfer-Launch (ITL) complex impoundments located within the Kennedy Space Center security zone are known spawning sites for red drum (Sciaenops ocellatus). However, recent construction of manatee exclusion bollards around culverts leading into these impoundments may impede movement to and from this critical habitat. The goals of this study were to: 1) utilize passive acoustic telemetry to document patterns of red drum movement and habitat use within and around the ITL impoundments to assess how manatee exclusion bollards and environmental conditions may impact movement of red drum; and 2) explore red drum movement in response to environmental disturbance, specifically a …
Understanding Sediment Biogeochemistry And The Role Of Juvenile Oysters On Recently Restored Eastern Oyster Reefs, Bryan Locher
Understanding Sediment Biogeochemistry And The Role Of Juvenile Oysters On Recently Restored Eastern Oyster Reefs, Bryan Locher
Electronic Theses and Dissertations
In recent decades, goals for the restoration of eastern oyster (Crassostrea virginica) populations along the eastern coast of the United States have shifted from increasing harvestable oyster fisheries to enhancing the range of ecosystem services provided by oyster reefs. By filtering large volumes of water and releasing nutrient-rich feces and pseudofeces, oysters can locally enhance sediment biogeochemical cycling compared to that of unstructured benthic environments. An ongoing restoration program in Mosquito Lagoon, FL was leveraged to assess the immediate impacts ( < 1 year) of restoration on sediment biogeochemical properties of oyster reefs. The first study measured both short-term and long-term pools of carbon, nitrogen and phosphorus on dead, natural and restored reefs periodically over one year. The second study investigated one of the contributions to sediment nutrient pools by comparing feeding and feces/pseudofeces nutrient content of juvenile and older oysters. Results show that inorganic nitrogen and phosphorus pools can change within weeks after restoration and total nutrient pools by 6 months post-restoration. Restored reefs experienced a 136 % increase in ammonium, 78 % increase in total nitrogen, 46 % increase in total phosphorus, and 75 % increase in organic matter concentrations after 12 months of restoration. These nutrient increases were all positively correlated with oyster density, shell length and reef height measured on each reef. When standardized to grams of dry tissue weight, juvenile oysters showed significantly higher rates of chlorophyll-a removal, release of ammonium, and biodeposits with higher concentrations of dissolved organic carbon, nitrite + nitrate, and ammonium. The short-term changes to biogeochemical cycling on eastern oyster reefs within the first year of restoration are important to managers seeking to monitor ecosystem service recovery and overall coastal ecosystem health.
Business In The Estuary, Party In The Sea: Migration Patterns Of Striped Mullet (Mugil Cephalus) Within The Indian River Lagoon Complex, Olivia Myers
Electronic Theses and Dissertations
Commercial and recreational environmental enterprises in the Indian River Lagoon (IRL), Florida supply nearly 10,000 jobs and produce $1.6 billion dollars a year in revenue. These waters contain iconic species of sportfish, including red drum, snook, and sea trout, as well as their lower trophic level prey such as snapper and mullet. Striped mullet (Mugil cephalus) are both commercially valuable as well as an indicator species for overall ecosystem health. From September to December, mullet in the IRL undergo an annual migration from their inshore foraging habitats to oceanic spawning sites. However, their actual migratory pathways remain unknown. To address …
Seascape Genetics And Rehabilitation Efficiency In The Florida Manatee, Madison Hall
Seascape Genetics And Rehabilitation Efficiency In The Florida Manatee, Madison Hall
Electronic Theses and Dissertations
The Florida manatee (Trichechus manatus latirostris) was recently downlisted federally from "endangered" to "threatened" despite acknowledgments of remaining threats to long term population persistence. Challenges to future manatee conservation include, but are not limited to, increases in frequency of harmful algal blooms, intensifying anthropogenic disturbance, and loss of warm-water habitat. The goals of this dissertation were 1) to assess threats to the manatee via a comprehensive, long-term (1973-2016), retrospective analysis of the manatee rescue and rehabilitation partnership (MRRP) and 2) to use seascape genetics analysis to examine whether abiotic, biotic, or anthropogenic seascape variables could significantly describe genetic distance patterns …
The Ecology Of Central Florida's Thief Ants (Hymenoptera: Formicidae: Solenopsis), Leo Ohyama
The Ecology Of Central Florida's Thief Ants (Hymenoptera: Formicidae: Solenopsis), Leo Ohyama
Electronic Theses and Dissertations
Thief ants of the genus Solenopsis are a diverse group of ants that are found in ant communities throughout the world. They have long been purported to practice lestobiosis, an interaction between small and larger-bodied ants, where small ants cryptically tunnel into larger-bodied ant nests within the subterranean environment and steal brood or eggs for consumption. Thief ants are extremely small, measuring 1-2 mm in length and many of the species within this group practice a subterranean life history, where they live the entirety of their lives exclusively belowground. Due to these key characteristics, the ecology and natural history of …
Hydrodynamic Limitations And The Effects Of Living Shoreline Stabilization On Mangrove Recruitment Along Florida Coastlines, Christian Pilato
Hydrodynamic Limitations And The Effects Of Living Shoreline Stabilization On Mangrove Recruitment Along Florida Coastlines, Christian Pilato
Electronic Theses and Dissertations
The recruitment success of mangroves is influenced by a variety of factors, including propagule availability, desiccation, herbivory, and hydraulic habitat limitations. Hydrodynamic forces (waves and currents) act as obstacles to mangrove recruitment, restricting the successful colonization of mangrove species. We evaluated the biological and physical limitations to mangrove recruitment through monthly shoreline surveys and lateral pull-tests. Surveys followed mangroves from propagule release through recruitment along the shorelines of De Soto National Memorial (Bradenton, FL), capturing differences in propagule availability and recruitment along natural areas and across differing forms of shoreline stabilization ("living shorelines" and revetments). Propagule densities were highest along …
Fear And Loathing In The Super Organism: Foraging Strategy Doesn't Change Forager Response In A Landscape Of Fear., Philip Schadegg
Fear And Loathing In The Super Organism: Foraging Strategy Doesn't Change Forager Response In A Landscape Of Fear., Philip Schadegg
Electronic Theses and Dissertations
Understanding how predators impact keystone species, like ants, is very important for our understanding of ecology because of ants' importance in shaping community dynamics and ecosystem functions. In this thesis I present research investigating the role of the ant-specialized spider Anasaitis canosa in influencing the foraging behavior of four ant species (Formica pallidefulva, Odontomachus ruginodis, Pheidole obscurithorax & Solenopsis invicta). Collectively, these four species use foraging strategies exhibited by most ants. I conducted two experiments to quantify the impacts of spider predation on ant prey. The first used forty colonies of four ant species to investigate how A. canosa changed …
Variation In Prospecting Behavior And Drivers Of Post-Fire Habitat Preference Among Juvenile Florida Scrub-Jays, David Sherer
Variation In Prospecting Behavior And Drivers Of Post-Fire Habitat Preference Among Juvenile Florida Scrub-Jays, David Sherer
Electronic Theses and Dissertations
Florida Scrub-Jays (Aphelocoma coerulescens, FLSJ; federally Threatened) are cooperatively breeding birds endemic to Florida and dependent on fire-maintained xeric oak scrub. FLSJs are year-round residents, highly territorial, and rarely disperse far from their natal territory. Lifetime reproductive success is highest among individuals breeding in early-successional habitat, usually less than 9 to 10 years post-fire. However, because scrub burns infrequently such early-successional, high-quality habitat is extremely limited and competition for it as breeding space is likely intense. Because some birds live long enough to experience habitat succession, FLSJs also occupy later-successional overgrown scrub, even though both survival and fecundity decline. Although …
Ribbeting Results: Emergent Infectious Diseases In Wetland Systems, Ariel Horner
Ribbeting Results: Emergent Infectious Diseases In Wetland Systems, Ariel Horner
Electronic Theses and Dissertations
North American amphibians have recently been impacted by two major emerging pathogens, the fungus Batrachochytrium dendrobatidis (Bd) and iridoviruses in the genus Ranavirus (Rv). Environmental, seasonal and host factors may play important roles in disease dynamics, but few studies incorporate these components into their analyses. Here, we investigated the role of environmental, seasonal, genetic and location effects on driving Bd and Rv infection prevalence and severity in a biodiversity hot spot, the southeastern United States. We used quantitative PCR to characterize Bd and Rv dynamics in natural populations of three amphibian species: Notophthalmus perstriatus, Hyla squirella and Pseudacris ornata and …