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Full-Text Articles in Life Sciences

Habitat Utilization And Salinity Tolerance Of The Sandbar Shark, Carcharhinus Plumbeus, In Virginia, Leonard Pace Jan 2006

Habitat Utilization And Salinity Tolerance Of The Sandbar Shark, Carcharhinus Plumbeus, In Virginia, Leonard Pace

Dissertations, Theses, and Masters Projects

No abstract provided.


The Influence Of Predation On The Nesting Ecology Of Diamondback Terrapins (Malaclemys Terrapin) In The Lower Chesapeake Bay, Victoria Ann Ruzicka Jan 2006

The Influence Of Predation On The Nesting Ecology Of Diamondback Terrapins (Malaclemys Terrapin) In The Lower Chesapeake Bay, Victoria Ann Ruzicka

Dissertations, Theses, and Masters Projects

No abstract provided.


Sources Of Mortality, Movements And Behavior Of Sea Turtles In Virginia, Katherine Lamont. Mansfield Jan 2006

Sources Of Mortality, Movements And Behavior Of Sea Turtles In Virginia, Katherine Lamont. Mansfield

Dissertations, Theses, and Masters Projects

Aerial surveys are commonly used to evaluate in-water sea turtle abundances. A correction is applied to account for turtles diving below the observed surface. Historically, observations of summer/fall surfacing behavior were used for this correction, assuming constant behavior among seasons. Using radio/acoustic telemetry, seasonal differences in sea turtle surfacing behavior were determined among Kemp's ridleys and loggerheads. Mean time spent at surface in the spring ranged between 9.9%-30.0% with significant differences among individuals. Observed surfacing times were higher than historic summer/fall observations (Byles 1988; 5.3%), indicating that historic springtime abundances were overestimated by 50%-80%. Aerial surveys (2001-2004) indicated a 65%-75% …


Size-Selectivity Of The Commercial Sea Scallop (Placopecten Magellanicus) Dredge: Evaluation The Performance Of The New Bedford Style Dredge Configured With 4-Inch Rings And A 10-Inch Twine Top Using The Select Model, Noelle Yochum Jan 2006

Size-Selectivity Of The Commercial Sea Scallop (Placopecten Magellanicus) Dredge: Evaluation The Performance Of The New Bedford Style Dredge Configured With 4-Inch Rings And A 10-Inch Twine Top Using The Select Model, Noelle Yochum

Dissertations, Theses, and Masters Projects

A size-selectivity curve was constructed to characterize the performance of the New Bedford style Atlantic sea scallop (Placopecten magellanicus) dredge when it is configured to meet the requirements of Amendment #10 to the Sea Scallop Fishery Management Plan. The curve was generated using the SELECT model on catch-at-length data, obtained by simultaneously towing a New Bedford style dredge and a non-selective National Marine Fisheries Service sea scallop survey dredge from commercial scallop vessels. Data were collected during three cruises in the Northwest Atlantic between 2005 and 2006. One cruise was completed in Georges Bank (Groundfish Closed Area II) and two …


Ecology And Conservation Of Virginia Shark Species: Analysis Of Thirty Years Of Virginia Long-Line Shark Census Data, 1974--2004, Daniel Stuart Ha Jan 2006

Ecology And Conservation Of Virginia Shark Species: Analysis Of Thirty Years Of Virginia Long-Line Shark Census Data, 1974--2004, Daniel Stuart Ha

Dissertations, Theses, and Masters Projects

Sharks of the Atlantic coast of the United States have suffered increased fishing pressure in last three decades. Commercial and recreational catches jumped in the mid to late 1980's, leading to regulation by the National Marine Fisheries Service in the early 1990's. The Virginia Institute of Marine Sciences' shark long-line survey, begun in 1974, and continuing to the present day, is thus well positioned to look at the effects of this fishing mortality on sharks. Using GAM modelling, six of ten shark species analyzed, including the most common species, Carcharhinus plumbeus, suffered declines of from 98-99% of early abundances in …


Effects Of Excitotoxic And Immunotoxic Lesions Of The Posterior Parietal Cortex On Attention, William M. Howe Jan 2006

Effects Of Excitotoxic And Immunotoxic Lesions Of The Posterior Parietal Cortex On Attention, William M. Howe

Dissertations, Theses, and Masters Projects

No abstract provided.


Particle Retention In Suspension-Feeding Fish: Kinematics, Oral Flow Speed, And Particle Retention During Tilapia Suspension Feeding With Gill Rakers Intact Vs Removed, Jennifer Claire Smith Jan 2006

Particle Retention In Suspension-Feeding Fish: Kinematics, Oral Flow Speed, And Particle Retention During Tilapia Suspension Feeding With Gill Rakers Intact Vs Removed, Jennifer Claire Smith

Dissertations, Theses, and Masters Projects

No abstract provided.


Migratory And Spawning Behavior Of American Shad In The James River, Virginia, Aaron W. Aunins Jan 2006

Migratory And Spawning Behavior Of American Shad In The James River, Virginia, Aaron W. Aunins

Dissertations, Theses, and Masters Projects

No abstract provided.


Physiological Consequences Of High Water Flow On The Coral Montastrea Annularis (Ellis And Solander, 1786), Lawrence W. Carpenter Jan 2006

Physiological Consequences Of High Water Flow On The Coral Montastrea Annularis (Ellis And Solander, 1786), Lawrence W. Carpenter

Dissertations, Theses, and Masters Projects

Water-flow is a vital component to the life histories of sessile marine invertebrates and essential to the structure and function of coral reefs. Recent studies have identified water-flow as an asset in the resistance to and recovery from short-term bleaching events of high irradiance and thermal increases. to determine whether the benefits of water-flow scale from the landscape level down to the flow patterns experienced over individual polyps and to quantify potential metabolic consequences, three studies were performed on Montastrea annularis (Ellis and Solander, 1786), using in situ heated bleaching flow-chambers during two saturation missions at the Aquarius underwater laboratory. …


Floristic Quality Index: Ecological And Management Implications In Created And Natural Wetlands, Douglas A. Deberry Jan 2006

Floristic Quality Index: Ecological And Management Implications In Created And Natural Wetlands, Douglas A. Deberry

Dissertations, Theses, and Masters Projects

We applied the Floristic Quality Index (FQI) to vegetation data collected across a chronosequence of created wetland (CW) sites in Virginia ranging in age from one to 15 years post-construction. at each site, we also applied FQI to a nearby forested reference wetland (REF), for a total of 30 sites (15 created, 15 reference). We tested the performance of the index against a selection of community metrics (species richness, diversity, evenness, percent native species) and site attributes (age, soil physiochemical variables). The relationship between FQI and community and environmental variables was analyzed with Spearman's rank order correlation coefficient and Canonical …


Incorporating Space Into Stock Assessments Of Marine Species, John F. Walter Jan 2006

Incorporating Space Into Stock Assessments Of Marine Species, John F. Walter

Dissertations, Theses, and Masters Projects

Spatial management of marine resources requires population dynamic parameters in much greater spatial detail than traditional stock assessments provide. This dissertation presents a suite of methods to improve the spatial prediction of population abundance, fishing and natural mortality and to make greater use of commercial catch data. The main objectives of this dissertation are to determine the efficacy of using the vast amount of data collected by on-board observers on commercial vessels in model-based estimation of abundance and to use the spatial autocorrelation to improve resource mapping and abundance estimation. The first paper presents a methodology for improving variogram estimation …


Development Of Generalized Index-Removal Models, With Particular Attention To Catchability Issues, Thomas F. Ihde Jan 2006

Development Of Generalized Index-Removal Models, With Particular Attention To Catchability Issues, Thomas F. Ihde

Dissertations, Theses, and Masters Projects

The index-removal method estimates abundance, exploitation and catchability coefficient, given surveys conducted before and after a known removal. The method assumes a closed population between surveys. Index-removal has seldom been applied due to its strong assumption of constant survey catchabilities. This work generalizes the method to allow multiple years of data to be incorporated, and the assumptions of the original model to be relaxed. If catchability is constant across years, precision can be improved by analyzing multi-year data simultaneously. Two multiple-year models were developed: the first, 1qIR, assumes constant catchability within and among years; the second, 2qIR, allows catchability to …


Development Of An Unstructured Grid, Finite Volume Eutrophication Model For The Shallow Water Coastal Bay: Application In The Lynnhaven River Inlet System, Yuepeng Li Jan 2006

Development Of An Unstructured Grid, Finite Volume Eutrophication Model For The Shallow Water Coastal Bay: Application In The Lynnhaven River Inlet System, Yuepeng Li

Dissertations, Theses, and Masters Projects

The shallow water region is an important portion of the estuarine and coastal waters, since it encompasses the entire land-water margin as the buffer zone and supports one of the most productive ecosystems. When light can penetrate to the sediment, it triggers the benthic microalgae community to perform photosynthesis, resulting in a benthic-pelagic exchange flux different from that of the deeper water. This study utilized the laboratory-measured benthic flux, and a suite of well-calibrated numerical models to examine the eutrophication process in the Lynnhaven River Inlet system with special emphasis on: the role played by benthic microalgae, and nutrient budgets …


Diel And Site-Specific Feeding Of Young Striped Bass In A Heterogeneous Nursery Habitat, Sarah C. Muffelman Jan 2006

Diel And Site-Specific Feeding Of Young Striped Bass In A Heterogeneous Nursery Habitat, Sarah C. Muffelman

Dissertations, Theses, and Masters Projects

The Chesapeake Bay spawning stock of striped bass, Morone saxatilis, is considered one of the largest sources of juvenile production along the Atlantic coast and exhibits a high degree of interannual recruitment variability. Year class strength is judged by near-shore seine surveys that cover major tributaries of Chesapeake Bay and survey results are incorporated into annual stock assessments. In these surveys, the contribution of the Rappahannock River (Virginia) to total production is significant. In this system, abundance of juveniles is highest at a single seine site, suggesting that juvenile production may be related to habitat heterogeneity and food availability. To …


A Molecular Technique For Specific Identification Of Western Atlantic Ocean Scombrids And An Analysis Of A Larval Scombrid Assemblage Off The Kona Coast Of Hawaii, Melissa A. Paine Jan 2006

A Molecular Technique For Specific Identification Of Western Atlantic Ocean Scombrids And An Analysis Of A Larval Scombrid Assemblage Off The Kona Coast Of Hawaii, Melissa A. Paine

Dissertations, Theses, and Masters Projects

No abstract provided.


Developing A Stock Assessment For The Barndoor Skate (Dipturus Laevis) In The Northeast United States, Todd Gedamke Jan 2006

Developing A Stock Assessment For The Barndoor Skate (Dipturus Laevis) In The Northeast United States, Todd Gedamke

Dissertations, Theses, and Masters Projects

The barndoor skate Dipturus laevis is one of seven species in the United States Northwest Atlantic skate complex. The species received little attention until a recent article published in Science reported that the barndoor skate might be on the brink of extinction. In this study, we address not only the virtual lack of information on the life history of the species, but also develop methodologies to assist in the assessment of the barndoor skate population. to investigate the life history of the species, data were collected from 2,310 specimens caught during commercial sea scallop dredging in the southern section of …


Variation In Egg Size And Number In Drosophila Subobscura, Minyoung Janet Yi Jan 2006

Variation In Egg Size And Number In Drosophila Subobscura, Minyoung Janet Yi

Dissertations, Theses, and Masters Projects

No abstract provided.


Community Structure And Biogeography Of Mussel Bed Communities At Pacific Hydrothermal Vents: Lau And North Fiji Back-Arc Basins, 32° S---East Pacific Rise, And 38° S---Pacific Antarctic Ridge, Elizabeth Anne Blake Jan 2006

Community Structure And Biogeography Of Mussel Bed Communities At Pacific Hydrothermal Vents: Lau And North Fiji Back-Arc Basins, 32° S---East Pacific Rise, And 38° S---Pacific Antarctic Ridge, Elizabeth Anne Blake

Dissertations, Theses, and Masters Projects

No abstract provided.


Wetland Vegetation Dynamics And Ecosystem Gas Exchange In Response To Organic Matter Loading Rates, David E. Bailey Jan 2006

Wetland Vegetation Dynamics And Ecosystem Gas Exchange In Response To Organic Matter Loading Rates, David E. Bailey

Dissertations, Theses, and Masters Projects

Created wetlands are often limited in soil organic matter, usually a long-term product of ecosystem succession. Although many studies have tested the effect of adding organic material to these systems, few if any, have quantified the effect of various loadings of organic matter in created wetlands. The goal of this study was to determine how vegetation composition, standing crop biomass, woody vegetation development, and ecosystem gas exchange varied in a created freshwater wetland along a gradient of soil organic carbon (0 to 336 Mg ha-1 loading rates). Plot surface elevation varied positively with OM loadings, suggesting that inundation/aeration may modify …


Role Of Apolipoprotein A-1 In Defense Against Bacteria By Striped Bass (Morone Saxatilis), L. Danielle Johnston Jan 2006

Role Of Apolipoprotein A-1 In Defense Against Bacteria By Striped Bass (Morone Saxatilis), L. Danielle Johnston

Dissertations, Theses, and Masters Projects

No abstract provided.


Population Genetic Structure Of Escolar (Lepidocybium Flavobrunneum) And A Molecular Phylogeny Of The Trichiuroidea, Kirsten Brendtro Jan 2006

Population Genetic Structure Of Escolar (Lepidocybium Flavobrunneum) And A Molecular Phylogeny Of The Trichiuroidea, Kirsten Brendtro

Dissertations, Theses, and Masters Projects

No abstract provided.


The Effects Of Climate Change On The Population Ecology Of The Atlantic Surf Clam, Spisula Solidissima, In The Middle Atlantic Bight, Adriana Picariello Jan 2006

The Effects Of Climate Change On The Population Ecology Of The Atlantic Surf Clam, Spisula Solidissima, In The Middle Atlantic Bight, Adriana Picariello

Dissertations, Theses, and Masters Projects

No abstract provided.