Marine Biology Commons^™

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 …

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 …

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 …

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 …

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 …

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 …

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 …

What Drives Larval Condition For Northern Anchovy (Engraulis Mordax)? Implications For Coastal Pelagic Species Recruitment Fluctuations And Fishery Management Practices, Michelle Robidas

Theses

Discerning the causes of population boom and bust cycles for coastal pelagic species (CPS) has been a major focus of fisheries management research for over a century. Year-class strength is contingent on larval survival and condition, which can be influenced by larval size at age and growth rate. These two factors, in turn, can be affected by maternal investment and environmental variables such as water temperature, salinity, oxygen, and chlorophyll a. We evaluated each of these factors from 127 two to eight week-old Northern Anchovy (Engraulis mordax) larvae off the coast of San Diego to San Francisco, …

Porifera: Biology And Medicinal Properties, Emma L. Rayfield

Undergraduate Honors Theses

The focus of this thesis is the possibility of oceanic medicine through understanding the general biology of poriferans, their symbionts, medicinal properties, and how we could harvest sponges conservatively. It was necessary to understand the basic biology of poriferans regarding their structures, differences in their classes, and how they obtain nutrition, develop, and reproduce. The ecology of the poriferans was also researched including their larval and sessile stages and how their environment determines where they settle. Additionally, ecology was examined including how poriferans interact with symbionts and other organisms. This then was utilized to seek whether poriferans had useful medical …

Inferring Exposure To Harmful Pseudo-Nitzschia Blooms From Ocean-To-Estuary Gradients In Domoic Acid Concentrations In Humboldt Bay Bivalves, Natasha Hope Ficzycz Winnacott

Cal Poly Humboldt theses and projects

Harmful algal blooms (HABs) result from outbreaks of any of several different species of toxin-producing phytoplankton and that can have major detrimental effects on marine ecosystems and pose severe health and economic threats to human communities. Of particular concern along the United States West Coast are HABs of pennate diatom genus Pseudo-nitzschia that produce the potent neurotoxin domoic acid (DA). The coastal ocean between Cape Mendocino, CA, and Cape Blanco, OR is a hotspot for Pseudo-nitzschia spp. HABs. Such blooms impact coastal fisheries and pose a potential threat to aquaculture operations in Humboldt Bay, California’s second largest estuary and largest …

Effects Of Oyster Aquaculture On Elasmobranch Abundance And Habitat Use In Humboldt Bay, Ca, Rose Harman

Cal Poly Humboldt theses and projects

Habitat modification from aquaculture can have large effects on natural communities, with the habitat complexity provided by aquaculture structure positively influencing benthic invertebrates and small fish abundance. However, the effects of aquaculture on larger predatory fish like elasmobranchs (i.e., sharks and rays), which use nearshore habitat to forage and provide top-down control of these ecosystems, is largely unknown. Over two years, I deployed baited remote underwater video systems (BRUVS) to examine the effects of oyster aquaculture and environmental variables such as habitat (mudflat or eelgrass), salinity (ppt), turbidity (m), temperature (°C), pH (mV), dissolved oxygen (mg · L^-1), …