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Full-Text Articles in Marine Biology
It's A Small World After All: Insights, Interferences, And Implications Of In Situ Chlorophyll Fluorescence Monitoring In Estuaries, James Silas Tanner
It's A Small World After All: Insights, Interferences, And Implications Of In Situ Chlorophyll Fluorescence Monitoring In Estuaries, James Silas Tanner
UNF Graduate Theses and Dissertations
Concentrations of the photosynthetic pigment chlorophyll a are used as a proxy for phytoplankton biomass by estuarine scientists to study eutrophication, food web dynamics, and harmful algal blooms. Coastal managers use chlorophyll as an indicator of nutrient pollution and for assessments to meet Clean Water Act standards. Chlorophyll a, as measured in the laboratory by extraction from monthly discrete water samples, is a core component of the National Estuarine Research Reserve (NERR) System-Wide Monitoring Program (SWMP). Field-deployable sensors based on the excitation and emission spectra of in situ chlorophyll have not been incorporated into SWMP to date because past …
Reproductive Biology Of The Spinner Shark Carcharhinus Brevipinna, Off The Southeast U.S. Coast, Kristin K. Palmrose
Reproductive Biology Of The Spinner Shark Carcharhinus Brevipinna, Off The Southeast U.S. Coast, Kristin K. Palmrose
UNF Graduate Theses and Dissertations
The spinner shark, Carcharhinus brevipinna, is a large coastal shark species that is common on the U.S. southeast coast and caught in both commercial and recreational fisheries. Little research has been conducted on the life history of C. brevipinna in the Northwestern Atlantic, presenting challenges for fishery management. This is especially true for reproductive biology, warranting a need to determine how rapidly individuals are reproducing and contributing to the population. This study aimed to characterize reproduction in C. brevipinna by determining size-at-maturity, reproductive seasonality, periodicity, and fecundity. This was accomplished by analyzing changes in reproductive tract morphology and histology, …
Benthic Microalgae Response To A Warming Climate And Shift In Foundational Vegetation Species In A Saltmarsh-Mangrove Ecotone, Gabriela Canas
Benthic Microalgae Response To A Warming Climate And Shift In Foundational Vegetation Species In A Saltmarsh-Mangrove Ecotone, Gabriela Canas
UNF Graduate Theses and Dissertations
The ecotone in Northeast Florida is experiencing rapid change as mangroves begin to encroach northward into saltmarsh dominated coastal wetlands. This is especially prevalent within the boundaries of the Guana Tolomato Matanzas National Estuarine Research Reserve where studies are attempting to understand the consequences of more mangroves. Although we are beginning to understand some of the implications of this shift in dominant vegetation, the true effects and the accompanying sustained climatic warming effects on the resilience of wetland habitats and their associated communities remains unknown. Primary producers such as benthic microalgae (BMA) are important food sources in both mangrove and …
Effects Of Aquatic Acidification On Calcium Uptake In White River Shrimp Litopenaeus Setiferus Gills, Maria-Flora Jacobs
Effects Of Aquatic Acidification On Calcium Uptake In White River Shrimp Litopenaeus Setiferus Gills, Maria-Flora Jacobs
UNF Graduate Theses and Dissertations
Previous research regarding aquatic acidification has examined the protonation of the carbonate and does not consider calcium to be a limiting factor. This is the first study to suggest that pH may affect the uptake of calcium in crustacean gills. This project describes ion transport mechanisms present in the cell membranes of white river shrimp Litopenaeus setiferus gill epithelium, and the effects of pH on the uptake of calcium by these means. Partially purified membrane vesicles (PPMV) of shrimp gills were prepared through a homogenization process that has been used previously to define ion transport in crab and lobster gill …
Characterization Of Vitellogenesis In The Bonnethead Shark Sphyrna Tiburo, Adrien Kathleen Mowle
Characterization Of Vitellogenesis In The Bonnethead Shark Sphyrna Tiburo, Adrien Kathleen Mowle
UNF Graduate Theses and Dissertations
Vitellogenin (Vtg) is a precursor to yolk-proteins produced in the liver of many invertebrates and non-mammalian vertebrates; its synthesis is stimulated by the hormone estradiol (E2). This study is the first to characterize vitellogenin synthesis in a placental viviparous elasmobranch, the yolk-sac placental bonnethead shark, Sphyrna tiburo. This study focused on determining where and when Vtg is produced, as well as what hormonal factors regulate Vtg production. The liver was confirmed as the site of Vtg production via immunohistochemistry. Immunoreactivity was also observed within granulosa cells of ovarian follicles; further experimentation is needed to determine if this is indicative …
Establishing Relationships Among Environmental Stressors, Host Immune Status, And Wasting Disease Susceptibility In The Dominant Seagrass Species Thalassia Testudinum, Paige Joy Duffin
UNF Graduate Theses and Dissertations
A growing body of evidence supports the observation that marine disease outbreaks, especially those caused by opportunistic pathogens, are increasing in frequency and severity. One genus of such pathogens, Labyrinthula, has been identified as the causative agent of seagrass wasting disease, an epidemic that has historically plagued seagrass beds around the world. It is suspected that pathogenicity is intimately linked to the ability of the host to initiate defense responses, but a lack of compelling evidence prevents any meaningful application of preliminary observations. This body of work investigated the roles of host genotype, host immune status, and environmental stressors …
The Effects Of The Red Tide Producing Dinoflagellate, Karenia Brevis, And Associated Brevetoxins On Viability And Sublethal Stress Responses In Scleractinian Coral: A Potential Regional Stressor To Coral Reefs, David A. Reynolds
UNF Graduate Theses and Dissertations
Coral cover is in decline on a global scale, with increased mortality events being attributed to a number of global and regional stressors. While the impacts of global stressors (e.g. sea surface temperature rise, ocean acidification) are well documented, there is growing interest in identifying and understanding the impacts of regional stressors. The reason for this change in focus is that regional stressors can often work in combination, sometimes synergistically, with global stressors and that stressors on a regional scale tend to be more easily mitigated by management practices. One regional stressor that impacts a myriad of marine organisms in …
The Social Structure And Mating Strategies Of Bottlenose Dolphins (Tursiops Truncatus) In The St. Johns River, Jessica Lea Ermak
The Social Structure And Mating Strategies Of Bottlenose Dolphins (Tursiops Truncatus) In The St. Johns River, Jessica Lea Ermak
UNF Graduate Theses and Dissertations
Across populations, bottlenose dolphins (Tursiops sp.) exhibit a fission-fusion pattern of associations, in which group size and composition change fluidly throughout the day. Beneath this seemingly ephemeral social structure, considerable variation exists across study sites. While females typically have moderate bonds with one another within a large social network, male-male bonds are variable, though males typically take one of two strategies; some males encounter females individually for opportunities to breed while others cooperate within a first-order alliance to collectively herd females. In addition, multi-tiered alliances in which two first-order alliances cooperate to defend or assist in the theft of a …