Marine Biology Commons^™

Brody-Bertalanffy Growth Curves From Tag And Recapture Studies On Cabezon (Scorpaenichthys Marmoratus) And Gopher Rockfish (Sebastes Carnatus) Of The Central Coast, Christie Yorke

Biological Sciences

No abstract provided.

Thermal Tolerance Of Age-0 Gulf Of Mexico Striped Bass (Morone Saxatilis): Ontogenetic And Genetic Effects, Corey Robert Anderson

Master's Theses

Striped bass, Morone saxatilis, were historically abundant in the Gulf of Mexico region but were largely extirpated from most Gulf rivers by the early 1960s. Since 1967 hatchery stocking has supported populations in Mississippi rivers and to date there is no evidence of natural reproduction. Intolerance of striped bass to high water temperature is a potential factor negatively impacting Gulf striped bass survival and reproductive fitness, and may be a limiting factor to reintroduction of the species in Mississippi. This work contributed to restoration efforts by establishing molecular tools necessary for genetic monitoring of striped bass restoration, and evaluating …

Quantifying Rates Of Autocompaction In The Pearl River Marsh, Louisiana, Jeremiah Nicholas Prouhet

Master's Theses

Annual rates of shallow autocompaction (< 1 m) were calculated in the upper ~one meter of sediment from six cores of a transect in the Pearl River Marsh (PRM), Louisiana, in order to determine the most significant sedimentary property controlling this process. Compaction-free wedge cores were sub-sampled at one centimeter intervals to collect the following data: age control, using 137Cs and 210Pb, and sedimentary variables, specifically, particulate organic carbon, bulk density, median grain size, porosity, and water content. An upper and an underlying sedimentary unit (named the 137Cs and 210Pb units) were defined between radiometric datum levels, and their sedimentary properties were statistically tested for significant differences using the non-parametric Mann-Whitney test. Rates of autocompaction were calculated from the model of Williams (2003), and both rates of autocompaction and sedimentation were tested for significant differences between the upper and lower sedimentary units.

The upper unit in the six cores generally had lower bulk density, higher water content, higher porosity, and higher particulate organic carbon than the underlying unit, but with some interesting exceptions. Additionally, annual autocompaction and sedimentation rates were greatest in the overlying unit at stations PR02 (0.39 ± 0.05 cm/y) and PR05 (0.42 ± 0.03 cm/y) and greatest in the underlying unit at stations PR02 (0.22 ± 0.08 cm/y) and PR03 (0.18 ± 0.06 cm/y). Based on Spearman correlations, rates of autocompaction were most strongly correlated to and influenced by rates of sedimentation rather …

Measuring And Comparing Quantum Yield In Two Species Of Marine Diatoms Subjected To Constant And Fluctuating Light Conditions, Matthew Leon Stone

Master's Theses

A small-scale study was conducted to determine the effects of light fluctuations on the photosynthetic efficiency of marine phytoplankton. Two species, Phaeodactylum tricornutum and Chaetoceros gracile were grown in specialized photobioreactors on a 12-hour:12-hour light:dark cycle. The cultures were diluted 50% daily to attain a specific growth rate of 0.70 d-1. To simulate vertical mixing in high turbidity habitats under various wind conditions, dense cultures were subjected to fluctuating light treatments with frequencies ranging from 0.10 Hz to 2.00 Hz. Parallel experiments subjected the cultures to static light conditions with equal total daily light doses as those of the cultures …

Phytoplankton Abundance And Species Composition In Relation To Environmental Paramenters In Coastal Mississippi Waters, Luz Karime Molina

Master's Theses

Phytoplankton pigments from Coastal Mississippi waters were measured to determine the spatial and temporal distributions and composition of phytoplankton communities. Concentration of phytoplankton pigments were analyzed using High Performance Liquid Chromatography (HPLC) and the compositional changes in phytoplankton communities were determined with CHEMTAX 1.95. Surface water was collected for two years (September 2007-November 2009) at three sampling sites on a monthly basis. The stations were located at the Bay of St. Louis (station 1), the Mississippi Sound (station 4) and the Mississippi Bight (station 8), following a salinity gradient. A time series of the observations documented the variability of different …

The Use Of Computed Tomography To Measure Biogenic Structures In Recently Hypoxic And Normoxic Sediments On The Louisiana Continental Shelf, Valerie Ann Hartman

Master's Theses

Over the past 60 years, seasonal hypoxia in the northern Gulf of Mexico has occurred with increased severity and over a greater area. To determine if biogenic structures in the northern Gulf of Mexico vary in response to hypoxic stress, the seafloor on the continental shelf of Louisiana was analyzed during the spring and fall of 2009 at four provinces of similar sediment type that differ in recent history of bottom water oxygen concentration. Subcores were analyzed by computed tomography (CT) to determine the number, diameter, length, volume, surface area, and depth of biogenic burrow structures in sediments where biogenic …

Field Ecology Patterns Of High Latitude Coral Communities, Kristi A. Foster

HCNSO Student Theses and Dissertations

Some climate models predict that, within the next 30-50 years, sea surface temperatures (SSTs) will frequently exceed the current thermal tolerance of corals (Fitt et al. 2001; Hughes et al. 2003; Hoegh-Guldberg et al. 2007). A potential consequence is that mass coral bleaching may take place (i) during warm El Niño-Southern Oscillation (ENSO) events which are predicted to occur in some regions more frequently than the current 3-7 year periodicity (Hoegh-Guldberg 1999; Sheppard 2003) or (ii) perhaps as often as annually or biannually if corals and their symbionts are unable to acclimate to the higher SSTs (Donner et al. 2005, …

Circulation Of The Western Antarctic Peninsula: Implications For Biological Production, Maria Andrea Piñones Valenzuela

OES Theses and Dissertations

The western Antarctic Peninsula (wAP) continental shelf is characterized by large persistent populations of Antarctic krill ( Enphausia superba) and by regions of enhanced concentrations of marine mammals and other predators (hot spots). This study focused on understanding the role of ocean circulation in providing retention/connectivity of wAP Antarctic krill populations and in maintaining biological hot spot regions. Numerical Lagrangian particle tracking simulations obtained from the Regional Ocean Modeling System (ROMS) configured for the wAP region provided quantitative estimates of retention, immigration and emigration from the wAP continental shelf. Additional simulations with a one-dimensional temperature-dependent growth model for krill …

Mycorrhizal Colonization Of Native Salt Marsh Plants On Mississippi's Gulf Coast And The Effects Of Commercial Mycorrhizal Inoculants On Nursery-Grown Plants, Kathryn Rondot Mcbride

Master's Theses

Salt marshes are important economically and ecologically to the Gulf Coast and other coasts worldwide. Due to human activities, many coastal salt marshes have been degraded or destroyed. Restoration efforts, through the replacement or addition of naturally occurring salt marsh plants, are taking place worldwide. Most restoration plants are raised in nurseries and are not ready for transfer to restoration sites for eight or nine months. Once the plants are at the restoration site many die due to transplant stress. Arbuscular Mycorrhizal Fungi (AMF) may be able to shorten the time the restoration plants need to stay in the nursery …

An Analytical Study Of Air-Sea Co2 Gas Exchange In The Northwest Mississippi Bight Region, Andrea Kathryn Braatz

Master's Theses

With the continued increase of carbon dioxide (CO2) emissions, researchers are concerned with accumulation of excess CO2 within the atmosphere. The ocean is an important sink for the drawdown of atmospheric CO2 concentrations. Due to high spatial and temporal variability, CO2 fluxes in the coastal ocean are not as well characterized as those for the open ocean. More specifically, data for the northern Gulf of Mexico (GOM) coastal region is lacking. A time series analysis of air-sea CO2 flux rates from May through December 2009 was conducted using data collected by The University of Southern Mississippi’s Central Gulf Ocean Observing …

Temporal And Spatial Variability Of Phytoplankton Biomass In Coastal Mississippi Waters, Lorin Matthew Dornback

Master's Theses

Chlorophyll concentrations were measured in western Mississippi coastal waters to determine the spatial and temporal variability of phytoplankton. Nutrients (nitrate, silicate, phosphate), river discharge, temperature, salinity, stratification, tides, currents and winds were measured in concert with the phytoplankton concentrations. The purpose of this study was to determine the seasonal variability in phytoplankton and what was driving the variability. This study was comprised of a three year (September 2007-November 2010) time series where samples were taken once a month for eight stations. Profiles of each station were taken using a Conductivity, Temperature and Depth (CTD) sensor and a WET Labs FL-3 …

Feeding Selectivity And Habitat Usage Of Esox Americanus, Scott Richard Clark

Master's Theses

Patterns of piscine prey selection and habitat usage of Esox americanus were assessed through a series of field and experimental studies. Although few detailed studies exist on the foraging behavior and habitat usage of E. americanus, throughout its range it may be an important trophic component in maintaining fish assemblage structure in many lower order streams. Across 17 sampled streams, the presence of E. americanus among reaches within streams was found to be strongly correlated with increasing levels of habitat complexity. Reaches occupied by E. americanus featured increased amounts of in-stream physical structure, increased variability in stream width and …

Mycorrhizal Colonization Of Native Salt Marsh Plants On Mississippi's Gulf Coast And The Effects Of Commercial Mycorrhizal Inoculants On Nursery-Grown Plants, Kathryn Rondot Mcbride

Master's Theses

Salt marshes are important economically and ecologically to the Gulf Coast and other coasts worldwide. Due to human activities, many coastal salt marshes have been degraded or destroyed. Restoration efforts, through the replacement or addition of naturally occurring salt marsh plants, are taking place worldwide. Most restoration plants are raised in nurseries and are not ready for transfer to restoration sites for eight or nine months. Once the plants are at the restoration site many die due to transplant stress. Arbuscular Mycorrhizal Fungi (AMF) may be able to shorten the time the restoration plants need to stay in the nursery …

Dissolved And Colloidal Element Transport Through The Coastal Transition Zone, Moo Joon Shim

Dissertations

There are several factors (e.g., hurricanes, floodplain, and anthropogenic sources) that could modify trace element behavior through the coastal transition zone (CTZ). However, there is still a lack of information about these variables in affecting trace elements in the CTZ. For this study, water samples were collected in the Pearl River (PR), Bay of St. Louis (BSL), and the Mississippi River plume to study the effects of these factors on trace element.

A possible effect of Hurricane Katrina on water quality was examined in the East Pearl River (EPR). Hurricane Katrina could have resulted in increased inputs of organic matter …

Invertebrate Zooid Polymorphism: Hydractinia Polyclina And Pagurus Longicarpus Interactions Mediated Through Spiralzooids, Charlotte M. Regula-Whitefield

All Theses And Dissertations

Evaluating the net interaction between symbionts can be challenging when one participant is a colonial animal with polymorphic zooids, because each zooid type has unique functions. The colonial hydroid Hydractinia polyclina has three distinct zooid types, each of which contributes particular components to the interaction with host hermit crabs. Of these three zooid types, the function of spiralzooids is not well understood. Previously, spiralzooids have been proposed to contribute a strong negative interaction component by directly reducing their host hermit crab’s reproductive output. However, this hypothesis is not supported by past or current data. I propose that spiralzooids instead function …

Nudibranch Predators Of Octocorallia, Eric Brown

HCNSO Student Capstones

Nudibranchs are soft-bodied marine heterobranch gastropod molluscs which lack a shell and mantle cavity. The basic body plan is bilaterally symmetrical with an expanded notum, but in regards to other physical characteristics they exhibit a wide range of forms. Compared to other molluscs, evolutionarily the head and body became flattened and streamlined and tentacles have been lost or shifted to different areas of the body. Nudibranchs are found in many variations of size and color; despite the fact that these animals in general are noted for flamboyant colors and prominent external anatomical structures, many species rely upon a more cryptic …

Activation Of Amp-Activated Protein Kinase As An Early Indicator For Stress In The Lobster, Homarus Americanus, Stephanie Podolski

All Theses And Dissertations

Variations in water temperature, salinity, pH, and oxygen concentration are stressors that marine invertebrates face on a daily basis. Each of these physiological stressors creates a large cellular demand for energy. In mammals, energy metabolism is regulated by the enzyme AMP-activated protein kinase (AMPK), which is highly conserved during evolution. This project was designed to test the hypothesis that AMPK is present and activated by temperature, hypoxia, and anoxia stress in the lobster, Homarus americanus.

Animals were exposed to a rapid and progressive increase in temperature (6ºC per hour) beginning at 14 ºC. We measured lactate concentrations and AMPK …

Population Dynamics Of Sheepshead (Archosargus Probatocephalus; Walbaum 1792) In The Chesapeake Bay Region: A Comparison To Other Areas And An Assessment Of Their Current Status, Joseph Charles Ballenger

OES Theses and Dissertations

Sheepshead recently have seen an increase in fishing pressure in Virginian waters of the Chesapeake Bay. This increase in fishing pressure has led to demands to install effective management measures to protect the fishery. However, no study regarding the population dynamics, and thus potential yield, of sheepshead has been conducted north of Cape Hatteras. We addressed the need for information regarding the population dynamics of Chesapeake Bay sheepshead by investigating their age distribution, growth rate and reproductive biology. We used this information to construct yield-per-recruit models, which local management agencies may use in the formation of scientifically based management measures. …

Functional Activation Of Cartilaginous Fish Melanocortin Receptors, Christina Lee Reinick

Electronic Theses and Dissertations

The evolution of the melanocortin receptor (MCR) gene family has been dictated by two genome duplication events (2R hypothesis). The gnathostomes are thus predicted to possess a minimum of four MCR genes. Previous studies on cartilaginous fish have shown evidence for the presence of only three MCRs. The purpose of this thesis is to functionally express the MC5R from the spiny dogfish (Squalus acanthias) and the putative MC2R and MC3R from the elephant shark (Callorhinchus milii); these receptors have not yet been fully characterized. In this study, SacMC5R was able to be expressed in CHO cells …

Basal Food Web Dynamics In A Natural Eelgrass (Zostera Marina) Community: Cage-Free Field Experimentation, Matthew A. Whalen

Dissertations, Theses, and Masters Projects

The relative strength of bottom-up and top-down processes operating within food webs is a fundamental determinant of community structure and function. In marine systems, inconspicuous but often highly abundant invertebrate herbivores (mesograzers) are implicated as strong consumers of primary production and important prey for higher-order consumers. Because of their small size, however, mesograzer abundance is not easily manipulated in the field, which limits our ability to adequately assess their grazing impacts. Seagrass systems present a pressing need for the study of food web dynamics because anthropogenic nutrient and sediment inputs decrease the amount of light reaching seagrass leaves, which limits …

Iron And Manganese Reduction In Bering Sea Shelf Sediments, Margaret E.S. Esch

WWU Graduate School Collection

The southeastern Bering Sea is known for high levels of primary productivity, which is iron-limited in off-shore waters. The sedimentary reduction of iron and manganese oxides can be significant pathways of organic matter oxidation in marine sediments, and may influence patterns of primary production in surface waters. The goal of this research was to investigate patterns of Fe and Mn reduction rates across the shelf of the southeastern Bering Sea, and to assess the relative importance of these pathways in sedimentary organic matter remineralization. During the spring and summer of 2009, sediment samples were collected from 36 locations across the …

Vectoring Algal Toxin In Marine Planktonic Food Webs: Sorting Out Nutritional Deficiency From Toxicity Effects, Amy K. (Amy Keita) Burgess

WWU Graduate School Collection

The present study determined whether increased mortality and delayed development of larval crabs fed heterotrophic prey that themselves have been fed toxin-containing algae is due to toxicity effects or nutritional deficiency. The effects on larval crabs of previous exposure to heterotrophic prey fed toxin-containing algae were examined. Effects of varying length of exposure of larvae to toxin-containing prey were also examined. The rotifer Brachionus plicatilis was used as a heterotrophic prey source for three larval crab species (Lophopanopeus bellus, Metacarcinus magister, and Glebocarcinus oregonensis). Two rotifer treatments were created, one of rotifers fed a toxin-containing alga (Alexandrium andersoni or A. …

Evaluating Methods For Optimizing Classification Success From Otolith Tracers For Spotted Seatrout (Cynoscion Nebulosus) In The Chesapeake Bay, Stacy Kavita Beharry

OES Theses and Dissertations

Identifying the natal sources of fish is an important step in understanding its population dynamics. Adult recruits are often sourced from multiple nursery areas, with good quality locations contributing disproportionately more fish to the adult stock. Because population persistence is strongly influenced by nursery habitat, methods that correctly identify the source of recruits are necessary for effective management. Within the last decade, otolith chemistry signatures have been increasingly used as a natural marker to delineate fish from a mixture of nursery sources. Despite the widespread use of otolith trace element and stable isotope ratios as habitat markers, the statistical approaches …

Comparison Of Wetland Assessment Methods, Kerstin Green

HCNSO Student Theses and Dissertations

After many decades of being considered useless and often destroyed wetlands have become valued for the many functions they provide. To make informed wetland management decisions biologists have to develop practical, rapid, and inexpensive ways to assess biological conditions and functions. Ideally these assessment methods have to measure more than one attribute of the wetland to represent the overall condition of the biological community. For this project I conducted field assessments at mitigation sites in Pembroke Pines, Florida, to see how the newest method used in the State of Florida, the Uniform Mitigation Assessment Method (UMAM), compared to the older …

A Tale Of Two Blooms: Dynamics Of Nitrogen Uptake By Harmful Algae In The Eastern Gulf Of Mexico And York River, Virginia, Usa, Lynn M. Killberg-Thoreson

Dissertations, Theses, and Masters Projects

The goal of this study was to determine the significance of dissolved inorganic nitrogen (DIN) and dissolved organic nitrogen (DON) to harmful phytoplankton. Two regions that experience frequent and persistent harmful algal blooms (HABs) were examined, the Eastern Gulf of Mexico and York River, Virginia. Nitrogen uptake by harmful algae in these regions was examined using a combination of stable isotopic (15N) tracer techniques and nutrient bioassays. In the Eastern Gulf of Mexico, kinetic parameters for uptake of N substrates by K. brevis were determined and indicated the greatest preference for ammonium (NH4+), although all substrates tested were taken up. …

Deep-Pelagic (0-3000m) Fish Assemblage Structure Over The Mid-Atlantic Ridge In The Area Of The Charlie-Gibbs Fracture Zone, April B. Cook

Dissertations, Theses, and Masters Projects

Only a miniscule fraction of the world’s largest volume of living space, the ocean’s mid-water biome, has ever been sampled. As part of the International Census of Marine Life field project Mid-Atlantic Ridge Ecosystems (MAR-ECO), a discrete-depth trawling survey was conducted in 2009 aboard the NOAA ship Henry B. Bigelow to examine the pelagic faunal assemblage structure and distribution over the Charlie-Gibbs Fracture Zone (CGFZ) of the northern Mid-Atlantic Ridge. This is the first MAR-ECO project aimed specifically at describing diel vertical migration as a distributional phenomenon. Discrete-depth sampling from 0-3000 m was conducted during both day and night in …

The Effects Of Seagrass Species And Trophic Interactions In Experimental Seagrass Communities, Althea F. P. Moore

Dissertations, Theses, and Masters Projects

No abstract provided.

Dynamics And Composition Of The Extracellular Polymeric Substances Produced By Benthic Microalgae: An In Situ 13c And 15n Approach, Stephanie Kara Salisbury

Dissertations, Theses, and Masters Projects

The land-­‐ocean margin is characterized by a shallow water column, which allows light to reach the benthos and supports a diverse community of benthic autotrophs. One group of benthic autotrophs, consisting of benthic diatoms, cyanobacteria and other photosynthetic microorganisms living near the sediment surface (i.e., benthic microalgae) accounts for a substantial amount of this primary production. Benthic microalgae are also tightly coupled to carbon and nutrient cycling processes carried out by the sediment bacterial community. Benthic microalgae exude complex biopolymers, called extracellular polymeric substances (EPS), which consist mainly of carbohydrates, but can contain proteins and nucleic acids. EPS serves multiple …

Ecological, Physiological, And Bio-Optical Characteristics Of Phaeocystis Globosa In Coastal Waters Of South Central Vietnam, Xiao Liu

Dissertations, Theses, and Masters Projects

No abstract provided.