Other Oceanography and Atmospheric Sciences and Meteorology Commons^™

Influence Of Natural And Anthropogenic Environmental Variability On Larval Fish Diet, Growth, And Condition In The Northcentral Gulf Of Mexico, Angie Hoover

Master's Theses

The northern Gulf of Mexico experiences high levels of freshwater runoff annually from various sources including the Mississippi River and Mobile Bay, among other sources. Early life history stages of fishes are especially vulnerable to environmental variability created by freshwater discharge. The objectives of this study were to describe the available prey field, diet, growth and condition of larval fishes with respect to various effects of freshwater discharge in the northern Gulf. The first chapter compared these parameters in larval Gulf Menhaden (Brevoortia patronus) collected from three different water masses characterized by physical and biological parameters after the …

Dormancy In The Amphistegina Gibbosa Holobiont: Ecological And Evolutionary Implications For The Foraminifera, Benjamin J. Ross

USF Tampa Graduate Theses and Dissertations

Dormancy, a state of severely decreased or suspended metabolism, is a widespread survival strategy in nature. In the Foraminifera, one of the most studied groups of marine organisms, its presence had been suggested by circumstantial evidence, but rarely studied directly until recently. Despite the lack of research, stressor-induced dormancy can significantly alter the way in which foraminiferal ecology is understood, especially in marginal environments. In this dissertation, I reviewed the evidence for dormancy in the foraminiferal literature, concluding that evidence for dormancy is widespread across the Phylum. I then explored the role of dormancy in the survival of the diatom-bearing …

Quantifying The Probability Of Lethal Injury To Florida Manatees Given Characteristics Of Collision Events., B. Lynn Combs

USF Tampa Graduate Theses and Dissertations

Wherever wildlife share space with boaters, collisions are a potential source of mortality. Establishing protection and speed zones are the primary actions taken to mitigate collision risk. However, creation of protection zones may be a point of contention with stakeholders as new zones can have significant socioeconomic impacts. The Florida Manatee is a prime example of a species whose abundance and viability are constrained by this balance between the needs of humans and wildlife on a shared landscape. The goal of this work is to help further understand the risk to manatees by quantifying the probability of lethal collisions. I …

Integrating Towed Underwater Video With Multibeam Acoustics For Mapping Benthic Habitat And Assessing Reef Fish Communities On The West Florida Shelf, Alexander Ross Ilich

USF Tampa Graduate Theses and Dissertations

Using a towed underwater video camera system, benthic habitats were classified along transects in a popular offshore fishing area on the West Florida Shelf (WFS) known as “The Elbow.” Additionally, high resolution multibeam bathymetry and co-registered backscatter data were collected for the entire study area. Using these data, full coverage geologic and biotic habitat maps were developed using both unsupervised and supervised statistical classification methodologies. The unsupervised methodology used was k-means clustering, and the supervised methodology used a random forest algorithm. The two methods produced broadly similar results; however, the supervised methodology outperformed the unsupervised methodology. The results of the …

Quantitative Validation Of Simulated Sea Ice Displacements, Bryan R. Mccormick

Mathematics & Statistics ETDs

Accurate simulations of Arctic sea ice are important for forecasting as well as for understanding the global climate. However, quantitative measures for simulation displacements are underutilized. We present five such measures proposed as being useful in the validation of simulated sea ice displacements. Using drifting buoy and satellite measurements of sea ice motion as observation, we apply the metrics in a comparison of observed displacements and predicted displacements from the Arctic sea ice simulation MPM\_ice. We find the metric scores are useful for comparing simulations and observations. The metrics also brought to light problems in the simulation MPM_ice, demonstrating their …

Using Ecosystem-Based Modeling To Describe An Oil Spill And Assess The Long-Term Effects, Lindsey N. Dornberger

USF Tampa Graduate Theses and Dissertations

The goal of the research conducted in this dissertation was to define and test methods to incorporate oil spill effects into an ecosystem-based assessment model. It was instigated by the Deepwater Horizon oil spill, an unprecedented oil spill in the United States for both depth and volume, with unknown implications for the health of the region. Using an ecosystem-based assessment model like Atlantis, with integrated oil spill dynamics, was the ideal candidate to predict long-term impacts such as decreased abundance or population recovery time. However no previous methodology existed for doing so in any ecosystem-based assessment model. Therefore, first I …

Evaluation Of Trace-Metal And Isotopic Records As Techniques For Tracking Lifetime Movement Patterns In Fishes, Jennifer E. Granneman

USF Tampa Graduate Theses and Dissertations

The focus of this work was on the use of otolith microchemistry and fish eye lens chemical profiles to measure fish movement and provided indirect support for the use of otolith microchemistry to examine exposure to crude oil. Chapter 1 provides an introduction to the applications of otolith microchemistry and eye lens isotopic profiles. In the second chapter, which examined associations between metal exposure and lesion formation in fishes collected after the Deepwater Horizon (DWH) oil spill, I did not observe any change in oil-associated metal concentrations in otoliths coinciding with the timing of the DWH oil spill. This suggests …

Spatial And Temporal Distributions Of Pelagic Sargassum In The Intra-Americas Sea And Atlantic Ocean, Mengqiu Wang

USF Tampa Graduate Theses and Dissertations

Pelagic Sargassum is one type of marine macroalgae that is known to be abundant in the Gulf of Mexico and Sargasso Sea. It is also known to serve as a critical habitat for many marine animals. In the past few years, large amounts of Sargassum have been reported in the Tropical Atlantic and Caribbean Sea (CS), causing significant environmental and economic problems. The goal of this study is to improve the understanding of Sargassum distributions, quantity, transport pathways, and bloom mechanisms in the CS and Tropic Atlantic through combining a variety of techniques including satellite remote sensing, field and laboratory …

An Interdisciplinary Approach To Understanding Predator-Prey Relationships In A Changing Ocean: From System Design To Education, Ileana M. Freytes-Ortiz

USF Tampa Graduate Theses and Dissertations

Climate change is ecologically and socially complex, deemed the most important issue of our generation. Through this dissertation I have approached climate change research through an interdisciplinary perspective, investigating how this phenomenon will affect marine ecological systems, how we can better develop experimental systems to answer ecological questions, and how we can effectively educate about this issue.

In Chapter 2, I provided accessible alternatives for researching the effects of climate change (elevated temperatures and pCO2) on marine ecosystems. I designed, built, and troubleshooted two accurate and inexpensive climate-controlled experimental systems capable of maintaining target conditions: a temperature-controlled system and an …

Diversity Of Ssdna Phages Related To The Family Microviridae Within The Ciona Robusta Gut, Alexandria Creasy

USF Tampa Graduate Theses and Dissertations

The gut microbiome is a complex ecosystem of bacteria, viruses, and fungi that strongly influences animal health. The bacterial component, for example, contributes orders of magnitude more gene products to host physiology than the host genome; thus, changes to the composition of these bacterial communities can have profound influences on the health of the animal. By infecting and lysing their hosts, viruses (particularly viruses infecting bacteria or phages) can affect critical functions in these environments, yet the consequences of these infections remain to be fully described. Most studies investigating gut viromes to date have focused on double-stranded DNA (dsDNA) phages …

Ecophysiology Of Oxygen Supply In Cephalopods, Matthew A. Birk

USF Tampa Graduate Theses and Dissertations

Cephalopods are an important component of many marine ecosystems and support large fisheries. Their active lifestyles and complex behaviors are thought to be driven in large part by competition with fishes. Although cephalopods appear to compete successfully with fishes, a number of their important physiological traits are arguably inferior, such as an inefficient mode of locomotion via jet propulsion and a phylogenetically limited means of blood-borne gas transport. In active shallow-water cephalopods, these traits result in an interesting combination of very high oxygen demand and limited oxygen supply. The ability to maintain active lifestyles despite these metabolic constraints makes cephalopods …

Evaluating Beach Water Quality And Dengue Fever Risk Factors By Satellite Remote Sensing And Artificial Neural Networks, Abdiel Elias Laureano-Rosario

USF Tampa Graduate Theses and Dissertations

Climatic variations, together with large-scale environmental forces and human development affect the quality of coastal recreational waters, creating potential risks to human health. These environmental forces, including increased temperature and precipitation, often promote specific vector-borne diseases in the Caribbean and Gulf of Mexico. Human activities affect water quality through discharges from urban areas, including nutrient and other pollutants derived from wastewater systems. Both water quality of recreational beaches and vector-borne diseases can be better managed by understanding their relationship with local environmental forces.

I evaluated how changes in vector-borne diseases and poor recreational water quality were related to specific environmental …

Spatial Dynamics And Productivity Of A Gulf Of Mexico Commercial Reef Fish Fishery Following Large Scale Disturbance And Management Change, Marcy Lynn Cockrell

USF Tampa Graduate Theses and Dissertations

The Gulf of Mexico commercial reef fish fishery has experienced significant management changes and disturbance in recent years, including transitioning two major fisheries from a traditional open access system into a limited entry individual fishing quota (IFQ) system in 2007 and 2010. Also in 2010, the Deepwater Horizon oil spill (DWH) released an estimated 4.9 million barrels of oil into the Gulf (~206 million U.S. gallons), and is still the largest U.S. environmental disaster to date. Emergency fishing closures initiated shortly after the oil spill began were successful in keeping tainted seafood from reaching markets. However, effects of DWH closures …

Numerical Experiment Of Sediment Dynamics Over A Dredged Pit On The Louisiana Shelf, Nazanin Chaichitehrani

LSU Doctoral Dissertations

Sediment transport over Sandy Point dredge pit in the northern Gulf of Mexico was examined using field measurements and a finely resolved numerical model. Delft3D model with well-vetted computational grid and input parameters was used. Numerical experiments were performed to examine the effect of wind-generated waves, wind-driven currents and their interaction on sediment dynamics in our study area during a cold front in November 2014 and fair-weather conditions between July and August of 2015. Sediment dispersal from the lower Mississippi River, sediment resuspension, transport and deposition with high spatial and temporal resolution were simulated. A reliable satellite-derived near-surface suspended particulate …

The Tensile Root Strength Of Emergent Coastal Macrophytes, Lauris Olivia Hollis

LSU Doctoral Dissertations

Spartina patens is a dominant emergent macrophyte in fresh, intermediate, and brackish marshes along the Atlantic and Gulf coasts of United States where its biomechanical properties are a key component of wetland health and resilience. Its root biomass and tensile root strength are essential for anchorage, erosion protection, and are important determinants of soil strength. Nutrients and the herbicide atrazine are suspected of negatively impacting this wetland plant and others. The objectives of this study were to: 1) ascertain the tensile root strength of five emergent coastal macrophytes in coastal estuaries, and 2) test the effects of nutrient addition, atrazine …

Stable Bromine Isotope Signature Of Bromoform From Enzymatic And Abiotic Formation Pathways And Its Application In Identifying Sources Of Environmental Bromoform In The Damariscotta River, Chengyang Wang

Honors Theses

Bromoform is a major source of atmospheric bromine. Most bromoform is produced by marine organisms including macroalgae and phytoplankton, using the enzyme bromoperoxidase (BPO). Bromoform can also be a byproduct of industrial processes such as water disinfection. Identifying sources of environmental bromoform is still a challenge. A novel technique of using quadrupole mass spectrometry coupled to a gas chromatography (GCqMS) was developed and optimized for Br isotope analyses. The study shows that GCqMS in single ion monitoring (SIM) mode can measure 81Br with precision of around ±0.7‰ (60pmol bromoform injected). This study aims to investigate stable Br isotopes of bromoform …