Species’ foraging choices influences their somatic growth rates, age at maturity, and time spent in vulnerable early life stages. Thus, differences in population demographics are often attributed to variability either in diet type, quality or quantity ingested. Knowledge of species diet selection, though currently limited, particularly in marine environments, can enhance our understanding of the roles of species in marine ecosystem and, at a finer scale, elucidate how nutrition and diet influences their growth and productivity. Marine green turtles (Chelonia mydas) are considered to be herbivores, predominantly consuming seagrass and algae. However, recent studies have suggested that they may exhibit omnivory in certain forage areas. Using juvenile green turtles as a case study, I coupled stable isotope analysis with a diet preference index to provide insights into the selection and plasticity of their diet. The study was conducted within two sites (Bonefish Hole and South Bimini) in Bimini, Bahamas in 2016. Habitat surveys were conducted to gather habitat data and determine resource availability. A dichotomy in diet was found between the sites: at Bonefish Hole, turtles exhibited a more generalist omnivorous diet, selecting for sessile filters feeders and green algae, whereas turtles in South Bimini had a more specialist herbivorous diet, primarily consuming seagrasses and selecting for red algae, when available. The foraging dichotomy found in this study by green turtles expands our understanding of the spatial differences in their biology in the Bahamas and provides novel information for turtle foraging in Bimini. Knowledge about differences in intra-specific diet, with a focus on diet selection and potential drivers, can elucidate the factors that influence critical life history traits and ultimately inform species management. / A Thesis submitted to the Department of Earth, Ocean and Atmospheric Science in partial fulfillment of the requirements for the degree of Master of Science. / Spring Semester 2018. / April 13, 2018. / Bayesian ellipses, carbon, habitat use, MixSIAR, nitrogen, Trophic ecology / Includes bibliographical references. / Mariana MPB Fuentes, Professor Directing Thesis; Jeff Chanton, Committee Member; Rob Spencer, Committee Member; Jeffrey A. Seminoff, Committee Member.

Karenia brevis is a marine dinoflagellate commonly found in the Gulf of Mexico and important both ecologically and economically due to its production of the neurotoxin brevetoxin, which can cause respiratory illness in humans and widespread death of marine animals. K. brevis strains have previously shown to be sensitive to changes in CO2, both in terms of growth as well as toxin production. Our study aimed to understand this sensitivity by measuring underlying mechanisms, such as photosynthesis, carbon acquisition, and photophysiology. K. brevis (CCFWC-126) did not show a significant response in growth, cellular composition of carbon and nitrogen, nor in photosynthetic rates between pCO2 concentrations of 150, 400 or 780 µatm. However, a strong response in its acquisition of inorganic carbon was found. Half saturation values for CO2 increased from 1.5 to 3.3 µM, inorganic carbon preference switched from HCO3- to CO2 (14% to 56% CO2 usage), and external carbonic anhydrase activity was downregulated by 23% when comparing low and high pCO2. We conclude that K. brevis must employ an efficient and regulated carbon concentration mechanism (CCM) to maintain constant carbon fixation and growth across pCO2 levels. A positive correlation with pCO2, although not statistically significant, in cellular brevetoxin content was found. This study is the first explaining how this socioeconomically important species is able to efficiently supply inorganic carbon for photosynthesis which can potentially prolong bloom situations. This study also highlights that enhanced CO2, as projected for a future ocean, can affect underlying physiological processes of K. brevis, some of which could lead to increases in cellular brevetoxin production and therefore increased impacts on coastal ecosystems and economies. / A Thesis submitted to the Department of Earth, Ocean, and Atmospheric Science in partial fulfillment of the requirements for the degree of Master of Science. / Fall Semester 2018. / September 17, 2018. / Brevetoxins, Carbon Concentrating Mechanism, Climate Change, Ocean Acidification, Photosynthesis, Red Tides / Includes bibliographical references. / Sven Kranz, Professor Directing Thesis; Angela Knapp, Committee Member; Olivia Mason, Committee Member; Michael Stukel, Committee Member; Janie Wulff, Committee Member.

Numerical models using one- and two-layer generalized geostrophic equations are developed and applied to the study of geostrophic turbulence. The classical results of geostrophic turbulence are extended by freeing the experiments from the restriction of weak vertical displacements, thereby allowing finite-amplitude, frontal effects. / Turbulence experiments with the one-layer model reveal an attracting length scale, which depends on the energy level. When the frontal effects are present, anticyclones merge into a few, coherent, large, and long-lived eddies, while cyclones shatter and form a small-scale, quasi-geostrophic background. / Experiments with the two-layer model indicate that a distinction exists between geostrophic turbulence at high and low energy levels. At high energy levels, when frontal effects are present and when the traditional quasi-geostrophic model is invalid, large, coherent anticyclones emerge from motions at scales less than the deformation radius; these are robust and retain their potential energy against the destructive action of baroclinic instability. This is an important new result, because so far, with only quasi-geostrophic models in use, it has long been thought that such eddies were unstable. Experiments with isolated eddies of varying sizes and amplitudes, with variable strength of the $\beta$ effect and with variable depth of the lower layer reveal that, at the finite amplitudes, anticyclones are far more stable than cyclones, and that strong anticyclones are more stable than weak eddies of either polarity. Eddies are also stable as the lower layer is deepened. The $\beta$-effect is destablizing when the lower layer is infinitely deep, and is stabilizing when the lower layer has a finite depth. / Source: Dissertation Abstracts International, Volume: 51-01, Section: B, page: 0370. / Major Professor: Benoit Cushman-Roisin. / Thesis (Ph.D.)--The Florida State University, 1989.

"Nineteen years of wind data over the North Atlantic are used to calculate a field of wind stress curl. An EOF analysis is performed on this field resulting in variance-qualified spatial patterns of wind stress curl and associated time series. A Monte Carlo technique is used to establish the statistical significance of each spatial pattern. The first four statistically significant EOF modes represent more than 50% of the curl variance. The spatial patterns of curl associated with these modes exhibit many elements of North Atlantic climatology. The associated time series are spectrally analyzed. Most of the variance is contained in annual and semiannual frequencies. Features observed include the individual annual variation of the subtropical high and the subpolar low, the annual oscillation of intensity between the above pressure centers, the influence of localized strong SST gradients and associated cyclogenesis regions, and the constant nature of the trades. The EOF curl patterns are in the form of simple standing waves with wavelength on the order of basin size"--Abstract. / Typescript. / "April, 1986." / "Submitted to the Department of Meteorology in partial fulfillment of the requirements for the degree of Master of Science." / Advisor: James O'Brien, Professor Directing Thesis. / Includes bibliographical references (leaves 35-36).

The total fatty acid content of an estuarine Flexibacter trip and the relative proportion of the constituent fatty acids were affected by growth temperature, aeration and salinity. The proportion of Cl6:lw5 the main fatty acid, did not change with temperature, but was produced in higher concentrations in xhe aiMOu*t o{ shaking cultures. In contrast, the amount of both linoleic and linolenic acids varied with temperature and aeration. The concentration of Cl6:lw5 per mg of protein changed with temperature, whereas the concentrations of both polyunsaturates were relatively constant. Both the proportion and concentration of the polyunsaturates were markedly stimulated by increases in salinity, although total fatty acid per mg protein decreased with it. The highest concentration of fatty acid per mg of protein did not coincide with the highest percentage of polyunsaturated fatty acids (PUFAs), when Inp was grown in different carbon sources. Inp growing in glucose had the highest concentration of PUFAs per mg of protein. Radio labelled acetate and palmitate were differentially incorporated into the fatty acids of Inp2 a variant of Inp. Addition of cAMP inhibited the incorporation of radioactive precursors into PUFAs. In contrast the antibiotic cerulenin inhibited the incorporation of radio labelled substrate acetate and variant into C16:1. This strongly suggests that lnp2 posseses both the anaerobic and aerobic pathway for UFAs synthesis. Whilst PUFAs were absent when another variant lnp3 was grown in media with an osmotic strength close to that of seawater, PUFAs were produced when Inp3 was grown in a high osmotic strength medium. Addition of cAMP to the high osmotic strength medium prevented PUFAs synthesis. Artemia salina was grown to adulthood on diets consisting of bacteria, bacteria plus algae and algae only. Generally, there were no differences in survival between the diets. However, different diets reflected differences in the total dry weight. Addition of algae to the Inp3 diet increased PUFAs concentration per animal dry weight. It is suggested that Inp3 may be able to provide both PUFAs and exoenzymes, which assist in the digestion of algae.

Thesis (B.S.)--Massachusetts Institute of Technology, Dept. of Naval Architecture and Marine Engineering, 1917. / by Tai Ming Wu, Chi Foo Yeh, Hin Yung Tu. / B.S.

Thesis (Nav.E)--Massachusetts Institute of Technology, Dept. of Naval Architecture and Marine Engineering, 1964. / Includes bibliographical references (leaf 73). / by Elcio de Sá Freitas. / Nav.E

Thesis (M.S.) Massachusetts Institute of Technology. Dept. of Naval Architecture and Marine Engineering, 1957. / Bibliography: leaf 21. / by Charles J. Henry. / M.S.

Thesis (Nav.E.)--Massachusetts Institute of Technology, Dept. of Naval Architecture and Marine Engineering, 1959. / Includes bibliographical references (leaves 76-79). / by John F. Pearson, Jr. and Robert B. Sims. / Nav.E.

Thesis (Nav.E.) Massachusetts Institute of Technology. Dept. of Naval Architecture and Marine Engineering, 1957. / Bibliography: leaf 94. / by Kevin James O'Toole and Kenneth Fox and Wilfred Robert Bleakley, Jr. / Nav.E.