Marine Biology Commons^™

A Comparison Of Diploid And Triploid Eastern Oysters For Aquaculture Production Under Extreme Temperatures And Salinities, Joshua H. Kim

LSU Master's Theses

Off-bottom aquaculture of Eastern oysters (Crassostrea virginica) is a nascent industry that is increasingly supported by the use of triploid oysters, which grow faster than diploids. Despite their growth advantage, elevated triploid mortality compared to diploids under high temperature, low salinity, or a combination of these conditions challenge consistent triploid production. Identifying the environmental thresholds at which differential triploid mortality occurs and predicting its economic impact are important to informing decision-making in oyster aquaculture. The goal of this thesis was to compare the biological and economic performance of diploid and triploid oysters under high temperature and low salinity conditions. …

Using Unmanned Aircraft Systems (Uas) To Assess Body Condition Of Common Bottlenose Dolphins (Tursiops Truncatus Truncatus) In The Indian River Lagoon, Florida, Jessica Jane Provenzano

Theses and Dissertations

Common bottlenose dolphins (Tursiops truncatus truncatus) in the Indian River Lagoon (IRL) have experienced four Unusual Mortality Events (UMEs). This stock is considered immunocompromised and is routinely subjected to persistent anthropogenic stressors such as fishing gear entanglement, vessel strikes, contaminants, and harmful algal blooms. Previous body condition assessments of this stock have involved invasive capture-release examinations or subjective methods using lateral body images. To improve precision, we investigated the use of photogrammetry data collected from noninvasive unmanned aircraft systems (UAS) combined with models developed from capture-release data to estimate morphometric parameters and subsequently determine the body condition of …

Investigating The Characteristics Of Bacteria Isolated From The Sea Scallop (Placopecten Magellanicus) Larvae And Tanks, Ayodeji Olaniyi

Electronic Theses and Dissertations

Placopecten magellanicus, also known as the Atlantic deep-sea scallop, is a valuable marine species on North America's northeastern coast. Although adult scallops can be successfully bred in hatcheries, a perplexing and destructive event takes place during the last two weeks of larval development: a sudden and severe mortality event that causes a drastic decline in populations, with some reports suggesting that survival from egg to competent larva can sometimes be reduced to as low as 1-10% during a span of 48 hours. The precise reasons for larval mortality in sea scallops remain unclear. Prior studies have investigated infections in …

Predicting Larval Dispersal And Population Connectivity Of Sea Scallops (Placopecten Magellanicus) On The Maine Coast Through An Individual-Based Model, Kelsey M. Ward

Electronic Theses and Dissertations

A hydrodynamic model of the coastal currents in the Gulf of Maine has been adapted to include an individual-based scallop larval development and behaviors module and used to estimate sea scallop (Placopecten magellanicus) larval dispersal along the eastern Maine coast. Larvae are released along the coastline out to a 40 m isobath during September and October, and dispersal is driven using the hydrodynamical model result for the region from 2014 through 2017. The origins of particles that “settle” in focal areas, such as Blue Hill Bay, Jericho Bay, and Narraguagus Bay, are determined from model runs, and the …

Response Of Fish Assemblages To Increased Connectivity And Habitat Restoration In Bayou St. John, A Degraded Waterway In New Orleans, La, Alia Jones

University of New Orleans Theses and Dissertations

Bayou St. John is a degraded waterway located within the City of New Orleans. The Bayou, which is disconnected from Lake Pontchartrain by floodgates, has undergone restoration efforts to improve connectivity through frequent floodgate openings and marsh habitat restoration outside of the floodgates. To assess possible responses of local fish assemblages to these restoration efforts, I analyzed long-term fish assemblage data from three sites located inside of the floodgates and one site located at the restored marsh outside of the floodgates. Two sites inside of the floodgates experienced significant changes in assemblages between the pre-opening period (2006-2012) and post-opening period …

Trophic Ecology Of Black Swallowers (Scombriformes: Chiasmodontidae: Chiasmodon) In The Deep-Pelagic Gulf Of Mexico, Travis J. Kirk

All HCAS Student Capstones, Theses, and Dissertations

The ecology of deep-pelagic predatory fishes remains poorly understood despite their importance as ecosystem regulators and energy transfer vectors. This study investigated the trophic ecology of three species of the predatory fish genus Chiasmodon (“black swallowers”) in the Gulf of Mexico, a region that serves as an analog for the global low-latitude deep pelagial, the world’s largest cumulative ecosystem. Foraging habits (e.g., selectivity, chronology, daily ration) of an “advanced” evolutionary fish in a system that is otherwise dominated by basal fish taxa, were quantitatively estimated via high-resolution stomach content analysis. A quantitative dataset of both predator and prey abundance, the …

Microplastic Quantification On The Effect Of Endoparasite Communities In Florida Seabirds, Sarah N. Prieto

All HCAS Student Capstones, Theses, and Dissertations

Microplastics are being studied in a variety of different projects to better understand their impact and threat to wildlife species. Although there is an understanding that microplastics are affecting our wildlife, there are still questions about how coastal seabirds come to ingest them and how the ingestion is altering critical biological processes, such as that for endoparasite communities. This project aims to determine a better understanding of two main objectives: assessment of the presence of secondary ingestion of microplastics in coastal seabirds due to the fish species they prey on and relationship between microplastics and endoparasite communities' structure and state …

Time Series Modeling To Ascertain Age In Fisheries Management, Kathleen Sue Kirch

OES Theses and Dissertations

The ability to assign accurate ages of fish is important to fisheries management. Accurate ageing allows for the most reliable age-based models to be used to support sustainability and maximize economic benefit. Structures used to age include bones, scales, and most commonly ear bones (otoliths). Assigning age relies on validating putative annual marks by evaluating accretional material laid down in patterns in fish otoliths, typically by marginal increment analysis. These patterns often take the shape of a sawtooth wave with an abrupt drop in accretion yearly to form an annual band and are typically validated qualitatively. Researchers have shown keen …

Quantifying The Respiratory Plasticity Of Common Fishes Of The Indian River Lagoon, Logan Exton

Honors Theses

Increasing water temperatures resulting from global climate change introduce new energetic demands for marine organisms. Higher energy input will be required to cope with a subsequently higher metabolic rate, affecting all aspects of an individual’s life and therefore their survival. Because estuaries act as a link between rivers and oceans, they and their inhabitants are considered to be the most threatened by climate change. Therefore, it is crucial to understand how these organisms will respond to increased stressors due to climate change. Checkered pufferfish (Sphoeroides testudineus) are among the most common teleost fish in the Indian River Lagoon, …

Characterizing The Habitat Use Of Pacific Coast Feeding Group Gray Whales (Eschrichtius Robustus) And The Spatial And Temporal Variability Of Their Benthic And Planktonic Invertebrate Prey In Northern California, Robyn E. Norman

Cal Poly Humboldt theses and projects

As opportunistic foragers, the Eastern North Pacific population (~20,000) of gray whales (Eschrichtius robustus) feed on diverse benthic and planktonic invertebrates in northern Alaska foraging grounds before they undertake one of the largest yearly migrations of any mammal to breed in Baja California, Mexico. While most of the population travels to the summer foraging grounds in Alaska, a sub-group of whales (~230) called the Pacific Coast Feeding Group (PCFG) summer between British Columbia, Canada, and northern California. The diet of PCFG whales typically includes high-density and/or high-caloric prey items like mysids and diverse species of amphipods, yet a …

Temperature Driven Variability In Bull Kelp (Nereocystis Luetkeana) Early Life Stages: A Comparative Study Of California Populations, Marzia Fattori

Cal Poly Humboldt theses and projects

This study investigated the effects of elevated temperatures on the reproductive and developmental stages of Nereocystis luetkeana, a crucial brown macroalgae found along the western coast of North America. My objectives were to 1) evaluate the impact of increasing temperature on the abundance of gametophytes from various sites, 2) determine the length of gametophytes that were affected by temperature on day 10 of culture, 3) assess the presence or absence of oocytes, sporophytes (young vs. multicellular), and abnormal cells, to understand the reproductive and stress responses to higher temperatures, and 4) determine if there is variation among early developmental …

Biophysical Factors Affecting Habitat Suitability For Crassostrea Virginica, Jason D. Tilley

Dissertations

Oyster reefs provide a variety of important ecosystem services. However, the mortality rate of eastern oyster, Crassostrea virginica, the dominant species that produces oyster reefs in the northern Gulf of Mexico, is increasing at an alarming rate due to a variety of abiotic and biological factors. I examined how biophysical factors, including the less-studied fatty acid profiles of the suspended particulate matter on which oysters feed, influenced morphometric condition of C. virginica.

I sampled suspended particulate matter (SPM) and oysters in-situ in the western Mississippi Sound, which historically supported the majority of oyster production in Mississippi waters. Sampling …

Effects Of Short-Term Pesticides Exposure On Swimming Behavior, Tissue Morphology, Oxidative-Nitrative Stress, Antioxidant Expression, And Cellular Apoptosis In Kidneys Of Goldfish, Esmirna Cantú

Theses and Dissertations

The prevalence of pesticides in the aquatic environment continues to increase due to anthropogenic activities and poses a threat to aquatic organisms. The aim of this study was to determine the short-term exposure (one-week) of pesticide mixtures (metolachlor, linuron, isoproturon, tebucanazole, alconifen, atrazine, pendimethalin; azinphos-methyl) on swimming behaviors, kidney morphology, and expression of nitrotyrosine protein (NTP), dinitrophenyl protein (DNP), superoxide dismutase (SOD), catalase (CAT), renin, and cellular apoptosis in goldfish (Carassius auratus). Results indicated that both low- and high-dose pesticide mixtures decreased the distance swimming behavior. Histological analysis showed pesticide exposure alters kidney morphology. DNP, NTP, and renin expressions, and …

Deep Ocean Vehicle Applications And Modifications, Nichole "Nikki" T. Arm

Master's Theses

This project had two primary goals: (1) to explore opportunities to further a deep-ocean vehicle’s reach using alternative pressure spheres, and (2) to implement an existing deep-ocean vehicle (lander) in active scientific research.

I gained a greater understanding of the limitations and design choices made for existing pressure spheres using Finite Element Analysis (FEA). My simplified FEA model predicted sphere failure for the existing 30% Fiber Glass 70% Nylon injection molded spheres at an external pressure of 3,954psi or 2,690m ocean-depth (only a 7.38% error compared to the tested minimum failure depth), so I determined it a valid model. I …

An Intersection Of Science & Art: Vitrification Approaches And Open-Fabricated Tools For The Biomedical Model Sea Hare, Aplysia Californica, Allyssa M. Oune

LSU Master's Theses

The California sea hare (Aplysia californica) is an important biomedical model for molecular neurobiology, electrophysiology, learning, and memory due to their well-mapped and large neurons and well-characterized learning capabilities. The National Resource for Aplysia (NRA, University of Miami) maintains large stocks of live animals and relies on regular shipments of wild-caught individuals to maintain genetic diversity. This is labor and cost-intensive, and environmental changes could alter the availability of wild animals increasing the need to preserve this genetic resource. One solution is vitrification, ultra-fast cooling which produces an amorphous glass that minimizes damage to cells. Aplysia californica presents …

Identification Of Biomarkers Of Sub-Lethal Algal Toxin Exposure In Atlantic Salmon (Salmo Salar) And Chinook Salmon (Oncorhynchus Tshawytscha) Using Differential Gene Expression Analysis, Brandon Ellingson

Biology Theses

Atlantic Salmon (Salmo salar) and Chinook Salmon (Oncorhynchus tshawytscha) are important culturally, recreationally, economically, and are a common aquaculture species in Canada and the United States. In the Pacific Northwest, blooms of toxic algae result in millions of dollars annually in losses for salmonid aquaculture producers. Blooms of harmful cyanobacteria produce microcystins which have been linked to net-pen liver disease which has large financial impacts on net pen salmon operations. Microcystin-LR, the most toxic variant, bioaccumulates in the liver and disrupts normal cellular activity by inhibiting protein phosphatases leading to deleterious effects on growth, immune status, and liver function. To …

Desperate Larva Or Death Before Dishonor: Can Old Coral Larvae Replenish Degraded Reefs?, Nepsis García Lara

All HCAS Student Capstones, Theses, and Dissertations

The recovery of coral populations depends largely on larval recruitment. Coral larvae settle in response to environmental cues that indicate habitat quality. Newly competent larvae typically avoid settling on substrates with high macroalgal cover and sedimentation, and thus might never recruit to degraded reefs, hindering their recovery. What is unknown is if settlement preferences change as larvae age. In the absence of suitable settlement cues, lecithotrophic larvae delay settlement and might do this until either dying (Death Before Dishonor Hypothesis) or becoming less discriminatory and settling regardless of their specific habitat requirements (Desperate Larva Hypothesis). To test these hypotheses in …

The Effect Of Water Flow Rates On The Survival And Growth Rates Of Three Caribbean Bouldering Coral Species Juveniles In An Indoor Versus Outdoor Environment, Ian Michael Johnson

All HCAS Student Capstones, Theses, and Dissertations

Coral reefs are vital ecosystems for the world’s oceans and humanity; however, they are threatened by climate change, disease, and local anthropogenic stressors, and need assistance to recover. Traditional reef restoration efforts (fragmentation and outplanting are helping but are limited in effectiveness by not increasing genetic diversity. Ex situ sexual propagation for corals provides new, genetically different coral recruits. However, this process is laborious, expensive and time consuming, especially at the scale required to effectively contribute to the widespread recovery. To lower costs, two key parameters that require optimization to hasten the growth of coral recruits are water flow and …

Biophysical Factors Impacting Sea Lice Settlement And Survival, Eleanor R. Glahn

Electronic Theses and Dissertations

Atlantic salmon (Salmo salar L.) aquaculture production in Maine is a valuable contributor to the economy, the expansion of which has been challenged by the parasitic salmon louse Lepeophtheirus salmonis. As planktonic organisms, the life of the salmon louse is primarily dictated by the physical conditions of the environment: the temperature for development time, salinity for survival, and current velocity for transport. Salmon lice are obligate parasites for whom the successful infection of a suitable host is critical to completion of their life cycle. However, little is understood about the effects of current velocity on infection success. Hydrodynamic …

Striped Blenny (Chasmodes Bosquianus) Presence And Behavior Between Sunrise And Sunset At Oyster Landing, South Carolina, Madeline Schuetze

Honors Theses

Lunar and diel cycles of fishes can help to interpret their behaviors during their reproductive season. Temperate estuaries are used by many benthic fishes for shelter and reproduction. This study examined the behavior and presence of striped blennies (Chasmodes bosquianus) during diel and lunar cycles. PVC pipe shelters were placed to mimic oyster shell nests, a natural habitat for blennies, and cameras were placed to monitor these shelters in April, May, and June 2022, during the striped blenny reproductive period. Video footage was reviewed and analyzed for the presence and behavior of both male and female blennies. Male presence …

Optimizing Strategies To Hydraulically Plant Atlantic Salmon Eggs Based On Fry Dispersal Patterns, Ernest J. Atkinson

Electronic Theses and Dissertations

The Gulf of Maine Distinct Population Segment of Atlantic Salmon has suffered from habitat loss and exploitation over the last century. Hatchery supplementation has prevented the extirpation of the species, but stocking methods represent tradeoffs between survival, domestication, and logistics. Egg planting, the use of eyed embryos, maximizes natural rearing opportunities which can be important for adaptation. This method, however, is logistically demanding and requires significant labor over large spatial, but short temporal, scales dictated by the ontogeny of the fish. However, the survival and dispersal behavior of Atlantic Salmon fry immediately after emergence from eggs planted in artificial nests …

Cross-Trophic-Level Dynamics In Aquatic Ecosystems And Their Application Across Ecological Contexts, Elliot M. Johnston

Electronic Theses and Dissertations

Cross-trophic-level dynamics represent biotic interactions between organisms in a food web that span two (e.g., predator-prey interactions) or more (e.g., bottom-up or top-down indirect interactions) trophic levels. These dynamics are fundamental to understanding a variety of animal attributes across ecological contexts, including life-history traits, population limitation, and resource management. A classic example illustrates how declines in sea otter (Enhydra lutris) populations had negative indirect effects on giant kelp (Macrocystis pyrifera) populations due to reduced top-down regulation of a primary kelp predator, purple sea urchin (Strongylocentrotus purpuratus). The need for management approaches that incorporate this food-web connectivity is evident in the …

Life History Of Two Goatfishes In Hawaii And Alternative Methodologies In Life History Research, Duncan Campbell

Undergraduate Honors Theses

Data-driven management of fisheries requires information on the life history of the species being managed. I provide new information on the life histories of two goatfish species in Hawaiʻi, Parupeneus insularis and Parupeneus cyclostomus. Fish were collected using spearfishing from the reefs of Oʻahu between 2020 and 2023. Macroscopic and microscopic methods of assigning maturity and reproductive stage were used to estimate size at maturity and seasonality. Parapeneus insularis females are estimated to reach 50% maturity at 188 mm fork length (95% CI: 177mm, 197mm), and 95% maturity at 245 mm FL (95% CI: 226mm, 287mm). P. cyclostomus females reach …

Fecal Pellet Production By North Atlantic Zooplankton, Michael Gibson

Undergraduate Honors Theses

Fecal pellet carbon (FPC) production by zooplankton is a significant component of the ocean’s biological carbon pump: the suite of biological processes that mediate export of carbon to the deep ocean, ultimately leading to the sequestration of atmospheric carbon dioxide in the ocean. In this study, mesozooplankton (zooplankton 0.2 mm to ~2 cm) were collected from the epipelagic zone in the temperate North Atlantic Ocean during day and night in May 2021. Zooplankton were live separated into five size fractions and incubated on board ship in natural surface seawater to measure fecal pellet production rate of the mixed mesozooplankton community. …

Are Rising Seas Pushing Ghost Crabs Out Of Their Comfort Zone?, Finn Gillette

Honors Theses

Ghost crabs (Ocypode quadrata) can be found on sandy beaches bordering the western Atlantic Ocean. These semiterrestrial crustaceans are often found between the swash zone and the dunes on beaches. Dunes are critical refuges for ghost crabs during storms and extreme tide events. This makes them a useful indicator species for monitoring the effects of global warming-induced sea level rise on beach biota, as their distribution patterns among beach zones may correlate with shifts found in other species. Beach surveys conducted from 2015 onward assessed the population density of ghost crabs on beaches of Horry and Georgetown counties …

Determination Of Cadmium Uptake In Crassostrea Virginica Shell Under Controlled Conditions, Joseph John Pavelites Ii

<strong> Theses and Dissertations </strong>

The objective of this thesis was to meet growing demand for the development of environmental biomonitors that protect ecosystems and public health. To do this, I determined the potential of oyster shell as a bioindicator of cadmium (Cd) in the environment by determining the mode of Cd uptake and relationships between Cd concentrations in the environment, shell, and soft tissues of juvenile eastern oysters (Crassostrea virginica Gmelin). I performed a review of the literature on the ability of oyster shell to retain metal contaminants and the factors that could affect this process (Chapter 2). I then reared C. virginica …

Physiological, Temporal, And Environmental Determinants Of Forage Fish Caloric Content In The Gulf Of Mexico, Rebecca R. Walsh

Honors Theses

Within the Gulf of Mexico, forage fish species serve as an important link between lower trophic levels and higher trophic levels, supporting economically valuable predator fish, birds, and mammals. Despite the key ecological role of forage fish, fisheries management efforts are often directed elsewhere; as a result, input data for fisheries models is unavailable for many forage fish species. To fill this knowledge gap, we sought to produce species-specific caloric content values for four forage fish species in the Gulf of Mexico: Atlantic croaker (Micropogonias undulatus), white trout (Cynoscion arenarius), bay anchovy (Anchoa mitchilli), …

Assessing The Dynamics Of The Southeast Florida Shark Community From 2013-2019 Via Catch Per Unit Effort And Stable Isotope Analysis, Alexandra Barth

All HCAS Student Capstones, Theses, and Dissertations

Sharks, as well as other top predators, are in drastic decline worldwide. As apex and near-apex predators, species such as nurse, lemon, and tiger sharks maintain balanced marine ecosystems by enacting top-down trophic control. However, this cascading effect is diminished with exploitation via commercial and recreational fishing. Sharks are generally long-lived, mature late, have long reproductive cycles, and produce few offspring. Much remains to be learned about the community structure, population trends and conservation statuses of shark populations worldwide. Comprehensive studies on the composition of the shark community in Southeast Florida north of Miami have been limited. This study assessed …

Age And Growth For Three Members Of The Family Gempylidae: Escolar (Lepidocybium Flavobrunnuem), Oilfish (Ruvettus Pretiosus), And Snake Mackerel (Gempylus Serpens), Sydney N. Daniels

All HCAS Student Capstones, Theses, and Dissertations

Escolar, Lepidocybium flavobrunnuem (Smith, 1849), Oilfish, Ruvettus pretiosus (Cocco, 1829), and Snake Mackerel, Gempylus serpens (Cuvier, 1829) belong to the family Gempylidae and are bycatch of the tuna-targeting pelagic longline fishery. There is limited know life-history information on these mesopelagic fishes, especially regarding growth rates. Age estimates were assigned by counting pairs of increment bands formed on the sagittal otoliths of Escolar (n = 133), Oilfish (n = 49), and Snake Mackerel (n = 46) collected between 2007 and 2022. Marginal increment analyses were used to validate age estimates and periodicity of increment formation, but no significant trends were observed …

Building Artificial Reefs From Recycled Construction Materials: A Feasibility Study, Nicholas H. Lew

Construction Management

Naturally occurring reefs are some of the world’s most biologically diverse ecosystems formed by jagged rocks tucked slightly below sea level. In recent years global warming began to pose a major threat to many reef habitats. Most relevant is the increase in surface seawater temperatures that cause coral to bleach, taking away major food sources for larger marine species. Researchers have combated this by deploying artificial reefs in substitution for naturally formed limestone rock formations in order to promote the expansion of coastal habitats. This project specifically aims to utilize construction waste towards the production of artificial reefs, effectively upcycling …