Physical Sciences and Mathematics Commons^™

Examining Paleoshorelines In The Eastern Gulf Of Mexico: Insights On Sea Level History And Potential Areas Of Interest For Habitat Management, Catalina Rubiano

USF Tampa Graduate Theses and Dissertations

An inventory of multibeam bathymetry containing relict drowned and lithified paleoshorelines has been compiled and analyzed in the first ever shelf-wide investigation of paleo sea level indicators on the west Florida shelf (WFS). On the largest scale, the WFS is a wide and gently sloping terrain that is characterized by a carbonate-rich sediment regime. This framework coupled with the region’s tectonic stability provided a setting in which sea level changes since ~ 20 ka have been recorded to a remarkable degree of resolution in the form of paleoshorelines which formed at sea level and were subsequently drowned and preserved in …

Stable Isotope Analysis Of Doryteuthis (Amerigo) Pealeii Eye Lenses To Determine Migratory Patterns In The Eastern Gulf Of Mexico Using Statoliths For Age Determination, Hannah M. Schwaiger

USF Tampa Graduate Theses and Dissertations

Doryteuthis (Amerigo) pealeii is a common fisheries squid that occurs in the Gulf of Mexico (GoM) and along the east coast of the United States. These squid are an important link in the food web, linking higher and lower trophic positions (Madsen et al., 2007), and they are also used for human consumption. The migration patterns of D. pealeii populations in the northwestern North Atlantic have been thoroughly studied when compared to those in the GoM. This research aims to combine statolith aging and stable isotope analysis to enhance the understanding of D. pealeii migration patterns throughout their short, sub-annual …

Investigation Of Retention Versus Export Of Planktonic Fish Eggs In The Northeastern Gulf Of Mexico, Bich Vi Viviane Nguyen

USF Tampa Graduate Theses and Dissertations

Planktonic fish eggs can be reliably identified with DNA barcoding, and their distribution and abundance can be monitored. Passive drifting fish eggs can be advected by ocean currents and as a result, can either be locally retained or exported away from the West Florida Shelf (WFS). Investigating their retention or export helps in the interpretation of egg abundance trends and in understanding their distribution in long-term surveys. The present investigation was performed in two steps using a combination of biological and physical oceanographic methods. First, fish fecundity of three species (Red Snapper, Vermilion Snapper, and Sand Perch) was assessed, first, …

Fish Communities On Natural And Artificial Reefs In The Eastern Gulf Of Mexico, Elizabeth C. Viau

USF Tampa Graduate Theses and Dissertations

Artificial reefs have been deployed throughout the world’s oceans to act as habitat and fishing enhancement tools. To expand current research on the role of artificial reefs in the marine community, ordination and multivariate regression methods were used here to analyze survey data of natural and artificial reefs. The reefs, located in the Northern Gulf of Mexico (NGOM) and on the West Florida Shelf (WFS), had been previously surveyed from 2004 to 2015 using remote operated vehicle and stationary video techniques. This study tested the hypothesis that similar functional roles are accounted for at both natural and artificial reef sites …

Regeneration Of Trace Metals During Phytoplankton Decay: An Experimental Study, Adrienne P. Hollister

USF Tampa Graduate Theses and Dissertations

Trace metals act as important nutrients, and sometimes toxins, to phytoplankton and other marine microorganisms. When phytoplankton decay, the elements in their cells are released back into the water column through regeneration (also referred to as remineralization), one of the processes responsible for governing concentrations of dissolved trace metals and macronutrients in depth profiles. In order to experimentally study regeneration, controlled experimental incubations of mixed phytoplankton assemblages from the Gulf of Mexico (GoM) and monocultures of the diatom Pseudo-nitzschia dolorosa and the dinoflagellate Karenia brevis were placed in the dark and monitored as they decayed with naturally present bacteria. Over …

Investigation Of Sediment Ridges Using Bathymetry And Backscatter Near Clearwater, Florida, Lewis Stewart

USF Tampa Graduate Theses and Dissertations

Changes in sediment morphology on the West Florida Shelf is investigated over a 14-year time period using multibeam bathymetry and backscatter in water depths between 10 m and 20 m, off the coast of Indian Rocks Beach, Pinellas County, Florida. Bathymetric surveys collected in 2002 (Kongsberg EM 3000 at 300 kHz) and 2016 (Reson 7125 at 400 kHz) were processed using CARIS Hips and Sips to create bathymetric maps and backscatter images. These data were then interpreted and compared in order to test hypotheses and answer questions related to sediment migration and sediment volume change.

The following questions prompted this …

Influence Of Water Column Stratification And Nutrient Gradients On The Migratory Behavior Of The Red Tide Dinoflagellate, Karenia Brevis, Matthew Garrett

USF Tampa Graduate Theses and Dissertations

Diel vertical migration (DVM) can offer motile phytoplankton a competitive advantage over other phytoplankton species. DVM has been well documented in the harmful dinoflagellate, Karenia brevis; however, the extent to which changes in nutrient regimes and density stratification modify migration patterns has not been thoroughly investigated. A 2 m experimental column was constructed with sensors and sampling ports at four depths to obtain fluorescence and temperature measurements and discrete water samples. The environmental parameters of the experimental column represented temperature and nutrient conditions found on the West Florida Shelf (WFS), where Karenia blooms frequently occur. Results demonstrated a clear …

Shelf-Scale Mapping Of Fish Distribution Using Active And Passive Acoustics, Carrie Christy Wall

USF Tampa Graduate Theses and Dissertations

Fish sound production has been associated with courtship and spawning behavior. Acoustic recordings of fish sounds can be used to identify distribution and behavior. Passive acoustic monitoring (PAM) can record large amounts of acoustic data in a specific area for days to years. These data can be collected in remote locations under potentially unsafe seas throughout a 24-hour period providing datasets unattainable using observer-based methods. However, the instruments must withstand the caustic ocean environment and be retrieved to obtain the recorded data. This can prove difficult due to the risk of PAMs being lost, stolen or damaged, especially in highly …

Automatic Red Tide Detection Using Modis Satellite Images, Wijian Cheng

USF Tampa Graduate Theses and Dissertations

Red tides pose a significant economic and environmental threat in the Gulf of Mexico. Detecting red tide is important for understanding this phenomenon. In this thesis, machine learning approaches based on Random Forests, Support Vector Machines and K-Nearest Neighbors have been evaluated for red tide detection from MODIS satellite images. Detection results using machine learning algorithms were compared to ship collected ground truth red tide data. This work has three major contributions. First, machine learning approaches outperformed two of the latest thresholding red tide detection algorithms based on bio-optical characterization by more than 10% in terms of F measure and …