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Succession Of The Late Summer Phytoplankton Blooms In The York River Estuary, Va, Heather Kathleen Corson Jan 2023

Succession Of The Late Summer Phytoplankton Blooms In The York River Estuary, Va, Heather Kathleen Corson

Dissertations, Theses, and Masters Projects

The influence of bottom-up and top-down controls on the formation and persistence of phytoplankton blooms has been well studied. However, the relative importance of these bottom-up and top-down controls vary spatially and temporally. In the tidal tributaries and mainstem of Chesapeake Bay, the summer dinoflagellate population follows a succession of bloom-producing species. The dinoflagellate species Margalefidinium polykrikoides and Alexandrium monilatum are currently considered the end of this succession. These species form near-annual blooms in the lower half of Chesapeake Bay and are considered harmful algal bloom (HAB) species due to their negative ecological impacts. However, analysis of long-term monitoring data …


Reconstructing Coastal Forest Retreat And Marsh Migration Response To Historical Sea Level Rise, Nathalie Schieder Jan 2017

Reconstructing Coastal Forest Retreat And Marsh Migration Response To Historical Sea Level Rise, Nathalie Schieder

Dissertations, Theses, and Masters Projects

Climate change assessments predict that rates of relative sea level rise will increase in the future, leading to enhanced inundation of low-lying coastal regions and a 20 – 50 % decline in salt marsh area by 2100. Global sea level rise began accelerating in the late 19th to early 20th century, and local rates along the U.S. mid-Atlantic coast are twice as fast as global estimates. Frequent flooding and salt stress associated with sea level rise lead to coastal transgression, and the survival of ecosystems depends on their ability to migrate inland faster than they erode and submerge. Here, I …


Myctophid Feeding Ecology And Carbon Transport Along The Northern Mid-Atlantic Ridge, Jeanna M. Hudson Jan 2012

Myctophid Feeding Ecology And Carbon Transport Along The Northern Mid-Atlantic Ridge, Jeanna M. Hudson

Dissertations, Theses, and Masters Projects

The Mid-Atlantic Ridge (MAR) is the largest topographic feature in the Atlantic Ocean, yet little is known about the food web structure and trophic ecology of fishes inhabiting mesopelagic waters along the MAR. To better understand the food web structure and to compare the feeding ecology of abundant MAR fishes to those in offridge areas, MAR-ECO, a Mid-Atlantic Ridge ecosystem field project of the Census of Marine Life, sampled the pelagic fauna of the northern MAR (Iceland to the Azores) during June-July, 2004. Samples were collected with two midwater trawls outfitted with multiple opening and closing cod ends to sample …


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 studies …


Estimating Detection Probabilities In Beach Seine Surveys For Estuarine Fishes, Branson D. Williams Jan 2010

Estimating Detection Probabilities In Beach Seine Surveys For Estuarine Fishes, Branson D. Williams

Dissertations, Theses, and Masters Projects

Detectability, the probability that a species is encountered if it inhabits a site, is often overlooked in fisheries research despite its potential to obscure habitat use inferences. Detectability can be estimated using models that also provide an estimate of occupancy (Ψ), the probability that a species inhabits a site. I used these models to estimate both probabilities, and to examine factors affecting detectability and occupancy for three fishes in Chesapeake Bay tributaries: young-of-the-year striped bass (Morone saxatilis), yearling Atlantic croaker (Micropogonias undulatus), and spottail shiner (Notropis hudsonius). Occupancy models were fitted to data from a seine survey conducted during summer, …


Variability In Juvenile Growth, Mortality, Maturity, And Abundance Of American Shad And Blueback Herring In Virginia, Troy D. Tuckey Jan 2009

Variability In Juvenile Growth, Mortality, Maturity, And Abundance Of American Shad And Blueback Herring In Virginia, Troy D. Tuckey

Dissertations, Theses, and Masters Projects

Young-of-year (YOY) population dynamics of American shad and blueback herring in Virginia's rivers were examined with an emphasis on variability in growth and mortality rates. In addition, an analysis was conducted to relate juvenile abundance indices of American shad to adult indices to establish a stock-recruitment relationship. to accomplish the stock recruitment relationship, an additional study that examined maturation schedules and inter-annual variability in maturation schedules among stocks was performed. Results of population dynamics studies found that growth and mortality rates of American shad and blueback herring varied by river and year and that conspecific abundance was an important factor …


Mortality Of Diamondback Terrapins In Blue Crab Traps: Population Changes And Conservation In Southeastern Virginia, Megan Ann Rook Jan 2009

Mortality Of Diamondback Terrapins In Blue Crab Traps: Population Changes And Conservation In Southeastern Virginia, Megan Ann Rook

Dissertations, Theses, and Masters Projects

No abstract provided.


The Survival Benefit Of Benthic Macroalgae Gracilaria Vermiculophylla As An Alternative Nursery Habitat For Juvenile Blue Crabs, Justin A. Falls Jan 2008

The Survival Benefit Of Benthic Macroalgae Gracilaria Vermiculophylla As An Alternative Nursery Habitat For Juvenile Blue Crabs, Justin A. Falls

Dissertations, Theses, and Masters Projects

The Chesapeake Bay blue crab is in decline. One of the threats to it is the loss of its once plentiful nursery habitat, seagrass, due to baywide eutrophication and climate change. The emergence of the non-native benthic macroalga Gracilaria vermiculophylla may offer the blue crab an alternative nursery if it can provide juvenile crabs a refuge from predation. The ability of Gracilaria to protect juvenile blue crabs was investigated in mesocosm and field survival studies, which were combined into a larger dataset. All of these studies used tethering and therefore a tethering validation study in mesocosms accompanied these experiments. In …


Parasitism In Deep-Sea Chemosynthetic Mussels: Parasitism In Bathymodiolus Mussels From Deep-Sea Seep And Hydrothermal Vents, Megan E. Ward Jan 2004

Parasitism In Deep-Sea Chemosynthetic Mussels: Parasitism In Bathymodiolus Mussels From Deep-Sea Seep And Hydrothermal Vents, Megan E. Ward

Dissertations, Theses, and Masters Projects

No abstract provided.


Comparison Of Mussel-Bed Faunas At Blake Ridge And Florida Escarpment Seeps, Kathleen Elizabeth Knick Jan 2003

Comparison Of Mussel-Bed Faunas At Blake Ridge And Florida Escarpment Seeps, Kathleen Elizabeth Knick

Dissertations, Theses, and Masters Projects

No abstract provided.


Tidal Freshwater And Oligohaline Benthos: Evaluating The Development Of A Benthic Index Of Biological Integrity For Chesapeake Bay, Robyn C. Draheim Jan 1998

Tidal Freshwater And Oligohaline Benthos: Evaluating The Development Of A Benthic Index Of Biological Integrity For Chesapeake Bay, Robyn C. Draheim

Dissertations, Theses, and Masters Projects

No abstract provided.


Correspondence Between Environmental Gradients And The Assemblage Structure Of Littoral Fishes In The Tidal Portion Of Three Virginia Coastal Plain Rivers, Clifford Michael Wagner Jan 1997

Correspondence Between Environmental Gradients And The Assemblage Structure Of Littoral Fishes In The Tidal Portion Of Three Virginia Coastal Plain Rivers, Clifford Michael Wagner

Dissertations, Theses, and Masters Projects

No abstract provided.


Habitat Complexity As A Determinant Of Juvenile Blue Crab Survival, Jessica L. Schulman Jan 1996

Habitat Complexity As A Determinant Of Juvenile Blue Crab Survival, Jessica L. Schulman

Dissertations, Theses, and Masters Projects

No abstract provided.


The Role Of Predation On Zostera Marina L (Eelgrass) Seed Abundance, James Fishman Jan 1994

The Role Of Predation On Zostera Marina L (Eelgrass) Seed Abundance, James Fishman

Dissertations, Theses, and Masters Projects

No abstract provided.


Mitochondrial Dna Variation In Striped Bass, Morone Saxatilis, From The Rappahannock River, Virginia, Carol Furman Jan 1989

Mitochondrial Dna Variation In Striped Bass, Morone Saxatilis, From The Rappahannock River, Virginia, Carol Furman

Dissertations, Theses, and Masters Projects

No abstract provided.


The Respiratory Response Of Busycon Canaliculatum (L) To Seasonal Variation Of Water Temperature, Salinity, And Oxygen, Harry Gregory Polites Jan 1987

The Respiratory Response Of Busycon Canaliculatum (L) To Seasonal Variation Of Water Temperature, Salinity, And Oxygen, Harry Gregory Polites

Dissertations, Theses, and Masters Projects

No abstract provided.


Effects Of Disruptive Grazing By The Mud Snail Ilyanassa Obsoleta On Mudflat Nematode Populations, David Ludwig Jan 1982

Effects Of Disruptive Grazing By The Mud Snail Ilyanassa Obsoleta On Mudflat Nematode Populations, David Ludwig

Dissertations, Theses, and Masters Projects

Population densities of the mud snail Ilyanassa obsoleta were manipulated in caging experiments on a salt marsh mudflat and in laboratory microcosms. Mud snails outcompete nematodes for food resources, but may increase resources available to deposit feeding groups. Mud snails reduce annelid (polychaete and oligochaete) populations by substrate disruption. Reduced annelid densities provide the nematode community with some release from predation and competition. In mudflat sediments, the nematode community responds to both primary (predation) and secondary (envirorm1ental release, food competition) interactions. Multiple levels of interactive coupling should be considered in any systems level investigation in this habitat.


Benthic Infaunal Community Formation In Dredged Areas In Hampton Roads, Virginia, Thomas Karl Duncan Jan 1974

Benthic Infaunal Community Formation In Dredged Areas In Hampton Roads, Virginia, Thomas Karl Duncan

Dissertations, Theses, and Masters Projects

The macrobenthic fauna in three dredged areas in Hampton Roads, Virginia was sampled for 14 months. Repopulation occurred very rapidly after the cessation of dredging, but the dominant species were generally not those previously recorded as mud-bottom dominants in the Hampton Roads area. The faunal changes through time somewhat agreed with those reported in classical successional sequences. This dissertation is from the Joint Program Degree from the College of William & Mary and University of Virginia and awarded by the University of Virginia.


Benthic Fish Associations On The Continental Slope Of The Middle Atlantic Bight, Douglas F. Markle Jan 1972

Benthic Fish Associations On The Continental Slope Of The Middle Atlantic Bight, Douglas F. Markle

Dissertations, Theses, and Masters Projects

No abstract provided.


The Distribution And Ecology Of The Gammaridea (Crustacea, Amphipoda) Of The Lower Chesapeake Estuaries, James B. Feeley Jan 1967

The Distribution And Ecology Of The Gammaridea (Crustacea, Amphipoda) Of The Lower Chesapeake Estuaries, James B. Feeley

Dissertations, Theses, and Masters Projects

No abstract provided.