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Patterns Of Abundance And Community Dynamics In Atlantic Coastal Sharks, Cassidy Peterson Jan 2016

Patterns Of Abundance And Community Dynamics In Atlantic Coastal Sharks, Cassidy Peterson

Dissertations, Theses, and Masters Projects

No abstract provided.


A Model Of Carrying Capacity And Ecosystem Impacts In A Large-Scale, Bivalve-Dominated Agro-Ecosystem: Hard Clam Aquaculture In Cherrystone Inlet, Va, Michael A. Kuschner Jan 2015

A Model Of Carrying Capacity And Ecosystem Impacts In A Large-Scale, Bivalve-Dominated Agro-Ecosystem: Hard Clam Aquaculture In Cherrystone Inlet, Va, Michael A. Kuschner

Dissertations, Theses, and Masters Projects

With the recent growth of the hard clam aquaculture industry, sites of intensive aquaculture have emerged as large-scale agro-ecosystems where the success of aquaculture production is dynamically linked to ecosystem function. Large scale clam aquaculture operations are associated with a range of potential positive and negative feedbacks related to nutrient dynamics, water and sediment quality, proliferation of macroalgae, and carrying capacity. Quantitative modeling tools are needed to support system-level planning related to site selection, scale of operations, production capacity and ecosystem function. The purpose of this study was to develop a model for Cherrystone Inlet, VA, where one-third (1.9 ...


Oyster Reef Connectivity Inferred Via Population Genetic Analysis, Brendan Douglas Turley Jan 2015

Oyster Reef Connectivity Inferred Via Population Genetic Analysis, Brendan Douglas Turley

Dissertations, Theses, and Masters Projects

A panel of 48 single nucleotide polymorphism markers (SNPs) was developed for use in a population genetic analysis of the Eastern Oyster Crassostrea virginica sampled from the lower Chesapeake Bay. The SNPs were developed from published and unpublished sequencing data and developed to be used on a Fluidigm Biomark. A selection of 95 SNPs were chosen initially for development and the best 48 were selected for downstream applications. This project was a collaboration with the non-profit Chesapeake Bay Foundation (CBF) to examine their oyster reef restoration project in the Lafayette River, Virginia. The CBF wanted to test a hydrodynamic connectivity ...


The Reproductive Biology Of Striped Bass (Morone Saxatilis) In Chesapeake Bay, Carissa L. Gervasi Jan 2015

The Reproductive Biology Of Striped Bass (Morone Saxatilis) In Chesapeake Bay, Carissa L. Gervasi

Dissertations, Theses, and Masters Projects

The Striped Bass (Morone saxatilis) is an anadromous finfish that supports a lucrative fishery along the Atlantic coast of the United States and serves as a vital component of estuarine food webs. Once Striped Bass stocks were restored after crashing in the late 1980s, abundance skyrocketed to record levels. Over the past decade however, abundance has steadily declined, concurrent with an outbreak of mycobacteriosis. Disease prevalence is currently >50%, and previous research has demonstrated diseasepositive fish exhibit slower growth and increased natural mortality compared to diseasenegative fish. The purpose of this research was to provide a contemporary description of Chesapeake ...


Physiological Stress And Post-Release Mortality Of White Marlin (Kajikia Albida) Caught In The U.S Recreational Fishery, Lela Sylvia Schlenker Jan 2014

Physiological Stress And Post-Release Mortality Of White Marlin (Kajikia Albida) Caught In The U.S Recreational Fishery, Lela Sylvia Schlenker

Dissertations, Theses, and Masters Projects

White Marlin (Kajikia albida) is a highly migratory species that occurs throughout temperate and tropical regions of the Atlantic Ocean and is the basis of a large sport fishery along the United States Atlantic coast. The single, Atlantic-wide stock is considered to be overfished, with less than one-third the spawning biomass estimated to be necessary for maximum sustainable yield. Billfish management measures adopted by the International Commission for the Conservation of Atlantic Tunas (ICCAT) and implemented in the U.S. by the National Marine Fisheries Service (NMFS), as well as increasing angler awareness of conservation, have resulted in the vast ...


Seasonal Nitrogen Uptake And Regeneration In The Water Column And Sea-Ice Of The Western Coastal Arctic, Steven E. Baer Jan 2013

Seasonal Nitrogen Uptake And Regeneration In The Water Column And Sea-Ice Of The Western Coastal Arctic, Steven E. Baer

Dissertations, Theses, and Masters Projects

The logistical difficulties of research in extremely low temperatures and lack of access to the Arctic have meant that there is a historic dearth of knowledge of coastal Arctic biogeochemistry, especially during winter when sea ice is present. Recent observations, however, indicate that the Arctic is changing rapidly. Changes include increased temperatures, decreased extent and volume of sea ice, and increased freshwater inputs. How these changes influence biogeochemical cycles is an open question, especially in the highly productive coastal regions of the Chukchi Sea. Here I present nitrogen (N) uptake and regeneration rates for phytoplankton and bacteria measured in the ...


Improvements In Triploid Crassostrea Virginica Production: Characterizing The Diploid Parent, Brian R. Callam Jan 2013

Improvements In Triploid Crassostrea Virginica Production: Characterizing The Diploid Parent, Brian R. Callam

Dissertations, Theses, and Masters Projects

The effect of triploidy to effect faster growth and increased survival compared to diploid oysters is called the ‘triploid advantage’ and this advantage in the Chesapeake Bay for Crassostrea virginica is the principal reason for the value of triploid C. virginica in the Chesapeake Bay, USA. The triploid advantage is hypothesized to be the result of genetic effects, physiological changes, or a combination of both. The causative genetic mechanisms at play may include additive genetic effects and heterosis while the physiological changes obtain from triploid sterility. The triploid advantage was examined by comparing 13 diploid and 13 triploid crosses across ...


Distribution And Impacts Of Invasive Bivalve Corbicula Fluminea In Tidal Freshwater York River Tributaries, Matthew Ryan Freedman Jan 2013

Distribution And Impacts Of Invasive Bivalve Corbicula Fluminea In Tidal Freshwater York River Tributaries, Matthew Ryan Freedman

Dissertations, Theses, and Masters Projects

The Asian clam, Corbicula fluminea, is one of the most invasive bivalves in the world but there is limited research on its presence in tidal freshwater systems. Despite its introduction into Chesapeake Bay tributaries in the 1970s, the initial colonization and subsequent development of populations of C. fluminea in the Mattaponi and Pamunkey sub-tributaries of the York River, Virginia, is mostly undocumented. This study assessed the spatial distribution and population structure of C. fluminea in tidal freshwater sections of these rivers (~45km) with benthic surveys during summer 2011 – 2012. Benthic grabs (2.4L, 0.023m2) taken at 40 sites in ...


Foraging Ecology And Habitat Use Of The Northern Diamondback Terrapin (Malaclemys Terrapin Terrapin) In Southern Chesapeake Bay, Diane C. Tulipani Jan 2013

Foraging Ecology And Habitat Use Of The Northern Diamondback Terrapin (Malaclemys Terrapin Terrapin) In Southern Chesapeake Bay, Diane C. Tulipani

Dissertations, Theses, and Masters Projects

The northern diamondback terrapin (Malaclemys terrapin ) is the only estuarine turtle residing along western Atlantic and Gulf of Mexico coasts of North America. Through predation, terrapins may be a key species in coastal marine habitats by exerting top-down control on marsh invertebrates, and thereby help to maintain healthy marshes. Despite the terrapin's ecological importance, there has not been a thorough study of terrapin foraging ecology and movements in lower Chesapeake Bay. In this dissertation, the research focused on the foraging habits of diamondback terrapins and their effects within salt marsh and seagrass habitats of lower Chesapeake Bay. I provided ...


Interannual And Regional Differences In Krill And Fish Prey Quality Along The Western Antarctic Peninsula, Kate E. Ruck Jan 2012

Interannual And Regional Differences In Krill And Fish Prey Quality Along The Western Antarctic Peninsula, Kate E. Ruck

Dissertations, Theses, and Masters Projects

Polar zooplankton and fish safeguard against the seasonality of food availability by using the summer months to build large reserves of lipids, which in turn are utilized to meet the metabolic demands of apex predators such as penguins, seals, and whales. A warming trend in the northern part of the western Antarctic Peninsula (WAP) has led to a decrease in perennial and summer sea ice, an increase in heat content over the shelf, and lower phytoplankton biomass, which could affect prey quality. We compared prey quality, including elemental (C, N) content and ratios, total, neutral, and polar lipid content, and ...


Movements, Growth, And Mortality Of Chesapeake Bay Summer Flounder Based On Multiple Tagging Technologies, Mark J. Henderson Jan 2012

Movements, Growth, And Mortality Of Chesapeake Bay Summer Flounder Based On Multiple Tagging Technologies, Mark J. Henderson

Dissertations, Theses, and Masters Projects

The research projects presented in this dissertation used multiple tagging technologies to examine the movements, growth, and mortality rates of summer flounder tagged and released in Chesapeake Bay. In the first two chapters, I used acoustic, archival, and conventional tags to examine the behavior of summer flounder on different spatial scales. Investigating the movement behavior of individuals on different scales is an important step towards understanding how large-scale distributions of a population are established. Based on the observed behaviors of summer flounder, I hypothesize that the movements of these fish are primarily related to foraging behavior while they are resident ...


Patterns Of Population Structure And Historical Dispersal In Squaloid Sharks: A Species-Level Approach Using Molecular Markers, Ana Christina Pimenta Verissimo Jan 2012

Patterns Of Population Structure And Historical Dispersal In Squaloid Sharks: A Species-Level Approach Using Molecular Markers, Ana Christina Pimenta Verissimo

Dissertations, Theses, and Masters Projects

Squaloids (Order Squaliformes) are a highle diverse group of mostly deepwater habitats (> 200 m). Many species are regularly caught in commercial fisheries worldwide but their low productivity and correspondingly low intrinsic rebound potentials make them particularly vulnerable to population depletion and overexploitation. of special concern to fisheries management and conservation efforts are the spiny dogfish Squalus acanthias, the leafscale gulper shark Centrophorus squamosus and the Portuguese dogfish Centroscymnus coelolepis. These taxa have recently been declared overfished in several parts of each species' distribution but management efforts have been made to recover the "stocks" without a good understanding of the species ...


Molecular Marker Development For The Discrimination Of Atlantic And Pacific Blue Marlin (Makaira Nigricans), Laurie Sorenson Jan 2011

Molecular Marker Development For The Discrimination Of Atlantic And Pacific Blue Marlin (Makaira Nigricans), Laurie Sorenson

Dissertations, Theses, and Masters Projects

No abstract provided.


Habitat Complexity And Habitat Function Of Native (Crassostrea Virginica) And Non-Native (C. Ariakensis) Oysters In The Chesapeake Bay Region, Heather D. Harwell Jan 2010

Habitat Complexity And Habitat Function Of Native (Crassostrea Virginica) And Non-Native (C. Ariakensis) Oysters In The Chesapeake Bay Region, Heather D. Harwell

Dissertations, Theses, and Masters Projects

Complex oyster reefs created by the Eastern oyster, Crassostrea virginica, though once prominent features of the Chesapeake Bay region, have become relatively scarce in comparison to historic descriptions. This decline, caused by a combination of overfishing, disease, habitat destruction and pollution, this decline continues despite substantial restoration efforts that have spanned decades. In response to this decline, the states of Virginia and Maryland considered the intentional introduction of the non-native Suminoe oyster, C. ariakensis. Previous studies questioned the reef-building capability of this Crassostrea species, which may affect its habitat function. Through a combination of field and mesocosm studies, I examined ...


The Life History Of Longnose Gar, Lepisosteus Osseus, An Apex Predator In The Tidal Waters Of Virginia, Patrick E. Mcgrath Jan 2010

The Life History Of Longnose Gar, Lepisosteus Osseus, An Apex Predator In The Tidal Waters Of Virginia, Patrick E. Mcgrath

Dissertations, Theses, and Masters Projects

Longnose gar (Lepisosteus osseus) inhabit all of the major tributaries of Chesapeake Bay in Virginia, extending from fresh to estuarine waters. Literature concerning longnose gar from tidal environments is limited and this is study concerns important aspects of the life history (e.g., growth, reproduction, dimorphism, movements, and diet). Age, growth, and reproduction are important life history aspects for understanding the biology of fishes and may be affected by the environment in which an individual lives. This study found no differences in the age, growth, and fecundity parameters between longnose gar from tidal portions of Chesapeake Bay tributaries and previous ...


"You Have No Boss Here To Work For": Women And Labor In Chesapeake Bay Fishing Communities, Elizabeth Marie O'Grady Jan 2010

"You Have No Boss Here To Work For": Women And Labor In Chesapeake Bay Fishing Communities, Elizabeth Marie O'Grady

Dissertations, Theses, and Masters Projects

No abstract provided.


Assessing Genetic Variation Within And Among Native Populations And Hatchery Stocks Of Crassostrea Ariakensis Using Microsatellite Markers, Jie Xiao Jan 2009

Assessing Genetic Variation Within And Among Native Populations And Hatchery Stocks Of Crassostrea Ariakensis Using Microsatellite Markers, Jie Xiao

Dissertations, Theses, and Masters Projects

Assessing genetic variation within and among native populations and hatchery stocks of Crassostrea ariakensis using microsatellite markers In response to the dramatic decline of eastern oyster (Crassostrea virginica) populations in the Chesapeake Bay, introduction of the non-native Asian oyster Crassostrea ariakensis has been proposed. Currently several hatchery stocks of C. ariakensis, derived from a few wild populations along the coast of Japan and China, are being maintained in U.S. hatcheries in the Pacific northwest and on the east coast. In recent years, as the risks of the proposed introduction are being assessed, these hatchery animals have been widely used ...


Investigating The Relationships Between Recruitment Indices And Estimates Of Adult Abundance For Striped Bass, Weakfish, And Atlantic Croaker, Justine R. Woodward Jan 2009

Investigating The Relationships Between Recruitment Indices And Estimates Of Adult Abundance For Striped Bass, Weakfish, And Atlantic Croaker, Justine R. Woodward

Dissertations, Theses, and Masters Projects

Establishing the relationships between recruitment indices and estimates of adult abundance using fishery-independent data continues to remain one of the principal challenges faced by fisheries scientists due to the lack of concurrent monitoring programs designed to target different life stages of the same species. In Chesapeake Bay, however, multiple, fishery-independent surveys currently monitor the relative abundance of YOY and adult fishes. Using the available data from these surveys, the relationships between estimates of relative abundance for young-of-year and adults of striped bass (Morone saxatilis), weakfish (Cynoscion regalis), and Atlantic croaker (Micropogonias undulatus) were examined. Year-class strength was reflected in subsequent ...


Egg Capsule Hatching Success In Rapana Venosa And Urosalpinx Cinerea In Relation To Temperature And Salinity, Stephanie M. Gera Jan 2009

Egg Capsule Hatching Success In Rapana Venosa And Urosalpinx Cinerea In Relation To Temperature And Salinity, Stephanie M. Gera

Dissertations, Theses, and Masters Projects

The maintenance of a population within the geographic range is influenced by the physical and environmental conditions under which breeding occurs. It is hypothesized that environmental conditions under which egg capsules are successfully hatched will influence the range of potential habitat of the invasive veined rapa whelk, Rapana venosa, and the native Atlantic oyster drill, Urosalpinx cinerea, in the Chesapeake Bay. This study examines the environmental conditions of temperature, salinity, and the time of deposition of egg capsules within the reproductive period (here quantified as cumulative number of day degrees at egg capsule deposition). The range of R. venosa and ...


Natural Mortality Of Blue Crab: Estimation And Influence On Population Dynamics, David A. Hewitt Jan 2008

Natural Mortality Of Blue Crab: Estimation And Influence On Population Dynamics, David A. Hewitt

Dissertations, Theses, and Masters Projects

The blue crab Callinectes sapidus supports one of the most important fisheries in the Chesapeake Bay and is the leading contributor to blue crab landings in the United States. Assessment and management of blue crab stocks has been hampered by a lack of estimates of natural mortality rates, a key parameter in assessment models. In Chapter 2, we demonstrate that the approach used for estimating natural mortality that had been used in past assessments was flawed, and provide justification for a superior alternative. In Chapter 3, we synthesize our current understanding of natural mortality rates in adult blue crab and ...


Novel Use Of A Natural Isotope Signature To Track Recruitment And Evaluate Age Determination Methods For The 2002 Year Class Of American Shad In The York River, Sally A. Upton Jan 2008

Novel Use Of A Natural Isotope Signature To Track Recruitment And Evaluate Age Determination Methods For The 2002 Year Class Of American Shad In The York River, Sally A. Upton

Dissertations, Theses, and Masters Projects

No abstract provided.


Age, Growth, And Demography Of The Sandbar Shark, Carcharhinus Plumbeus, Over Temporal And Spatial Scales, Jason G. Romine Jan 2008

Age, Growth, And Demography Of The Sandbar Shark, Carcharhinus Plumbeus, Over Temporal And Spatial Scales, Jason G. Romine

Dissertations, Theses, and Masters Projects

Numbers of sandbar sharks, Carcharhinus plumbeus, in the Northwest Atlantic have experienced drastic declines since the early 1980's reaching their minima during the early 1990's. Catch rates in the early 1990's were a mere 25% of those during the 1980's. Such drastic reductions in other fish stocks have often caused compensatory responses, most notably the cod stocks in the Northwest Atlantic. Compensatory responses in depressed populations may include decreased natural mortality, increased fecundity, or increased growth rates. Compensation for population fluctuations below carrying capacities have been recognized for many terrestrial and oceanic r-selected organisms, but few ...


Bottom-Up And Top-Down Controls On Sedimentary Ecosystem Functioning In A Seagrass Habitat, Amanda C. Spivak Jan 2008

Bottom-Up And Top-Down Controls On Sedimentary Ecosystem Functioning In A Seagrass Habitat, Amanda C. Spivak

Dissertations, Theses, and Masters Projects

Coastal seagrass ecosystems are complex habitats that are increasingly influenced by human perturbations. Disturbances that affect the strength of bottom-up (i.e. resource availability) and top-down (i.e. consumer) controls may also influence biomass distribution between trophic levels, sediment biogeochemistry, and seagrass ecosystem metabolism. Here, I experimentally tested how top-down and bottom-up perturbations interact with community structure (diversity, food chain length of epibenthic consumers) to alter sediment biogeochemistry and ecosystem metabolism in an experimental eelgrass (Zostera marina ) system. My data indicated that resource availability influenced SOM composition and ecosystem metabolism. Light availability tended to be a stronger determinant of SOM ...


A Molecular Analysis Of Atlantic Menhaden (Brevoortia Tyrannus) Stock Structure, Abigail J. Lynch Jan 2008

A Molecular Analysis Of Atlantic Menhaden (Brevoortia Tyrannus) Stock Structure, Abigail J. Lynch

Dissertations, Theses, and Masters Projects

Atlantic menhaden is an ecologically and economically important species along the U.S. east coast. As a filter-feeder and key prey fish, it provides a critical link between primary production, phytoplankton, and larger piscivorous predators, such as striped bass, bluefish, and weakfish. The species is also the target of one of the largest commercial fisheries in the country. Menhaden are assessed as a single, coastwide stock, and recent assessments indicate that it is not overfished. However, there is very limited population genetics data to support the assumption of a single stock. Additionally, the recent consolidation of the fishery and localization ...


Effects Of Shoreline Development And Oyster Reefs On Benthic Communities In Lynnhaven, Virginia, Amanda Sue Lawless Jan 2008

Effects Of Shoreline Development And Oyster Reefs On Benthic Communities In Lynnhaven, Virginia, Amanda Sue Lawless

Dissertations, Theses, and Masters Projects

Shoreline hardening and construction of restoration oyster reefs are occurring at rapid rates throughout Chesapeake Bay and little research has been conducted to determine whether installment of a hardened shoreline and oyster reef placement has an effect on the surrounding benthic infaunal communities. I investigated the effects of shoreline development and oyster reefs on benthic communities in Lynnhaven, Virginia. Throughout Lynnhaven, I determined the effects of shoreline type (natural marsh, oyster reef, rip-rap and bulkhead), sediment grain size, Total Organic Carbon/Total Nitrogen (TOC/TN) of the sediment, and predation (caging study) on density, biomass, and diversity of benthic infauna ...


Characterization Of Exotic Pathogens Associated With The Suminoe Oyster, Crassostrea Ariakensis, Jessica A. Moss Jan 2007

Characterization Of Exotic Pathogens Associated With The Suminoe Oyster, Crassostrea Ariakensis, Jessica A. Moss

Dissertations, Theses, and Masters Projects

The eastern oyster, Crassostrea virginica, once an integral part of the ecology and economy of Chesapeake Bay, has been severely depleted. Factors leading to the decline of the eastern oyster include over-harvesting, environmental degradation and disease pressure caused by the protozoans Haplosporidium nelsoni and Perkinsus marinus, known commonly as MSX and Dermo, respectively. Studies regarding the feasibility of introducing a nonnative oyster to the Bay were initiated, and field-based research on an Asian oyster, Crassostrea ariakensis, suggested that it might be a viable species for introduction. Research surrounding the proposed introduction has focused on recommendations such as those from the ...


The Infection Dynamics Of Pav1 In The Caribbean Spiny Lobster Panulirus Argus, Caiwen Li Jan 2007

The Infection Dynamics Of Pav1 In The Caribbean Spiny Lobster Panulirus Argus, Caiwen Li

Dissertations, Theses, and Masters Projects

Panulirus argus Virus 1 (PaV1) is an emerging disease in Caribbean spiny lobster Panulirus argus. It is considered a threat to the lobster industry in the Florida Keys. In order to understand the infection dynamics of the PaV1 virus in the lobster host, a sensitive and specific fluorescence in situ hybridization (FISH) assay was developed for diagnosis of PaV1 in lobsters. The lower limit of detection using the 110-bp DNA probe in a dot-blot hybridization for PaV1 was 10 pg of cloned DNA template and 10 ng of genomic DNA extracted from hemolymph of diseased spiny lobster. The probe specifically ...


Feeding Ecology Of Atlantic Menhaden (Brevoortia Tyrannus) In Chesapeake Bay, Patrick D. Lynch Jan 2007

Feeding Ecology Of Atlantic Menhaden (Brevoortia Tyrannus) In Chesapeake Bay, Patrick D. Lynch

Dissertations, Theses, and Masters Projects

No abstract provided.


Trophic Ecology And Growth Dynamics Of Striped Bass (Morone Saxatilis) In Chesapeake Bay, With Reference To Mycobacteriosis, Kathleen Anne Mcnamee Jan 2007

Trophic Ecology And Growth Dynamics Of Striped Bass (Morone Saxatilis) In Chesapeake Bay, With Reference To Mycobacteriosis, Kathleen Anne Mcnamee

Dissertations, Theses, and Masters Projects

No abstract provided.


Biomarker Responses In Fathead Minnows (Pimephales Promelas) During Exposure To Exceptional Quality Biosolids, Constance A. Sullivan Jan 2007

Biomarker Responses In Fathead Minnows (Pimephales Promelas) During Exposure To Exceptional Quality Biosolids, Constance A. Sullivan

Dissertations, Theses, and Masters Projects

No abstract provided.