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Empirical Valuation Of Primary And Alternative Nursery Habitats For The Blue Crab Callinectes Sapidus In Chesapeake Bay, Alexander C. Hyman
Empirical Valuation Of Primary And Alternative Nursery Habitats For The Blue Crab Callinectes Sapidus In Chesapeake Bay, Alexander C. Hyman
Dissertations, Theses, and Masters Projects
The blue crab (Callinectes sapidus) is a commercially and ecologically importantspecies found along the Atlantic coast of North and South America. These crustaceans play a critical role in coastal ecosystems, serving as both predators and prey in the food web. The blue crab supports a major fishery in Chesapeake Bay, where the species is a cultural icon. Juvenile blue crabs, the smallest and most vulnerable size classes of individuals, are reliant upon structurally complex habitats. Population dynamics of this species are therefore influenced by spatiotemporally fluctuating environmental variables, such as habitat availability. Understanding blue crab ecology is essential for managing …
Succession Of The Late Summer Phytoplankton Blooms In The York River Estuary, Va, Heather Kathleen Corson
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 …
Environmental Ecology And Life History Variation Of Perkinsus Marinus, Lydia M. Bienlien
Environmental Ecology And Life History Variation Of Perkinsus Marinus, Lydia M. Bienlien
Dissertations, Theses, and Masters Projects
Marine resources provide a growing world population with the opportunity to increase food security, particularly through aquaculture. Oysters are prominent aquacultured species, but marine diseases are a threat to the growth and sustainability of oyster culture. Perkinsus marinus is the most important oyster pathogen of the Atlantic and Gulf coasts of the U.S., where it causes substantial mortality. Despite being one of the most well-studied protozoan parasites of bivalve molluscs, much is still unknown about P. marinus. This research investigated multiple characteristics of P. marinus.In Chapter Two, the environmental ecology of P. marinus was explored through tidal sampling and year-long …
Reconstructing Coastal Forest Retreat And Marsh Migration Response To Historical Sea Level Rise, Nathalie Schieder
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 …
Assemblage Dynamics Of Larval Fishes In The York River Of Virginia And The Chesapeake Bay, Cindy Marlene Marin Martinez
Assemblage Dynamics Of Larval Fishes In The York River Of Virginia And The Chesapeake Bay, Cindy Marlene Marin Martinez
Dissertations, Theses, and Masters Projects
This thesis developed from the VIMS Larval Fish Monitoring Program, which began in 2007 as part of a study comparing the larval fish assemblages of Chesapeake and Delaware Bays. Ribeiro et al. (2015) analyzed data from the first three years of this time series to describe the temporal variation in the larval fish assemblages. After this initial study was completed (three years in duration), the sampling continued at the fixed station near the mouth of the York River, which was used to represent the Chesapeake Bay. For this thesis, therefore, eight years of data (2007-2015) were available to investigate temporal …
Spatial Modeling Of A Realized Niche: Investigating The Invasion Of Sweet Fennel (Foeniculum Vulgare Mill) Into Coastal Habitats Of Virginia's Eastern Shore, Kathryn Elizabeth Maccormick
Spatial Modeling Of A Realized Niche: Investigating The Invasion Of Sweet Fennel (Foeniculum Vulgare Mill) Into Coastal Habitats Of Virginia's Eastern Shore, Kathryn Elizabeth Maccormick
Dissertations, Theses, and Masters Projects
No abstract provided.
Structure, Drivers, And Trophic Interactions Of The Demersal Fish Community In Chesapeake Bay, Andre Buchheister
Structure, Drivers, And Trophic Interactions Of The Demersal Fish Community In Chesapeake Bay, Andre Buchheister
Dissertations, Theses, and Masters Projects
Management of fisheries resources is increasingly broadening its scope from single-species approaches to more holistic, ecosystem-based approaches that account for interactions of fish with a variety of ecological factors, such as predators, prey, and habitat. This ecosystem based fisheries management (EBFM) approach requires thorough biological and ecological understanding of systems pertaining to community structure, habitat suitability, and food web interactions. to strengthen the ecological underpinnings of EBFM efforts in Chesapeake Bay, the largest estuary in the USA, I conducted synoptic analyses examining the structure, function, and patterns of the bay's demersal fish community. This research relied on I0 years of …
Rise Of A Floater Class: Behavioral Adjustments By Breeding Bald Eagles In A Population Approaching Saturation, Courtney L. Turrin
Rise Of A Floater Class: Behavioral Adjustments By Breeding Bald Eagles In A Population Approaching Saturation, Courtney L. Turrin
Dissertations, Theses, and Masters Projects
No abstract provided.
Abundance, Structure And Function Of Zooplankton-Associated Bacterial Communities Within The York River, Va, Samantha L. Bickel
Abundance, Structure And Function Of Zooplankton-Associated Bacterial Communities Within The York River, Va, Samantha L. Bickel
Dissertations, Theses, and Masters Projects
Mesozooplankton function as microbial microhabitats and can support concentrations of bacteria orders of magnitude higher than in the surrounding water. These zooplankton-associated bacteria can have much higher production rates than their free-living counterparts. Portions of the zooplankton microhabitat may also be anoxic and provide refuge for anaerobic bacteria and their associated processes within the oxygenated water column. Despite their common presence in the marine environment, zooplankton-associated bacteria are largely ignored by microbial ecologists and zooplankton ecologists alike. Consequently, factors which influence zooplanktonassociated bacterial abundance, community composition and function, and how zooplankton-associated bacteria compare to free-living bacteria are not well known. …
Myctophid Feeding Ecology And Carbon Transport Along The Northern Mid-Atlantic Ridge, Jeanna M. Hudson
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 …
Copepod Carcasses, Mortality And Population Dynamics In The Tributaries Of The Lower Chesapeake Bay, David Thomas. Elliott
Copepod Carcasses, Mortality And Population Dynamics In The Tributaries Of The Lower Chesapeake Bay, David Thomas. Elliott
Dissertations, Theses, and Masters Projects
Several studies have documented the occurrence of substantial numbers of zooplankton carcasses in marine field samples. However, the potential effect of carcasses on conclusions resting on zooplankton abundance estimates, and the reasons for carcass occurrence have been largely disregarded. Many field studies do not account for the presence of carcasses in their sampling methodology. Zooplankton carcasses in situ are significant for several reasons. as concentrated particles of organic matter in the water column, zooplankton carcasses can be important vehicles for organic matter transport and hotspots of microbial abundance and activity. If dead animals are treated alive, carcasses could bias the …
The Life History Of Longnose Gar, Lepisosteus Osseus, An Apex Predator In The Tidal Waters Of Virginia, Patrick E. Mcgrath
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 …
Function Of Seed-Bank Ecology In Mid-Atlantic Semi-Annual And Perennial Zostera Marina Beds, Jessie C. Jarvis
Function Of Seed-Bank Ecology In Mid-Atlantic Semi-Annual And Perennial Zostera Marina Beds, Jessie C. Jarvis
Dissertations, Theses, and Masters Projects
The effects of water quality and sediment composition on mid-Atlantic semi-annual and perennial Zostera marina reproductive success, seed-bank viability, and seed germination were elucidated using laboratory and in situ experiments, quantitative field observations, and ecological model simulations. The sediment seed-bank was found to play a large role in the recovery of perennial Z. marina beds in the Chesapeake Bay and in the yearly re-establishment of beds in North Carolina which were determined to have a semi-annual life history. However, the resiliency provided by sediment seed-bank for both semi-annual and perennial Z. marina beds was limited as seeds remained viable for …
Mercury Levels In Newly Independent Songbirds, Anne Moire Condon
Mercury Levels In Newly Independent Songbirds, Anne Moire Condon
Dissertations, Theses, and Masters Projects
No abstract provided.
The Effects Of Mercury On The Nesting Success And Return Rate Of Tree Swallows (Tachycineta Bicolor), Rebecka L. Brasso
The Effects Of Mercury On The Nesting Success And Return Rate Of Tree Swallows (Tachycineta Bicolor), Rebecka L. Brasso
Dissertations, Theses, and Masters Projects
No abstract provided.
Floristic Quality Index: Ecological And Management Implications In Created And Natural Wetlands, Douglas A. Deberry
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 …
The Influence Of Predation On The Nesting Ecology Of Diamondback Terrapins (Malaclemys Terrapin) In The Lower Chesapeake Bay, Victoria Ann Ruzicka
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.
Predator Management And Colonial Culture, 1600-1741: A Study In Historical Ecology, Samuel Taylor Elswick
Predator Management And Colonial Culture, 1600-1741: A Study In Historical Ecology, Samuel Taylor Elswick
Dissertations, Theses, and Masters Projects
No abstract provided.
Parasitism In Deep-Sea Chemosynthetic Mussels: Parasitism In Bathymodiolus Mussels From Deep-Sea Seep And Hydrothermal Vents, Megan E. Ward
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.
Plumage As A Habitat For Bacilli, Justine M. Whitaker
Plumage As A Habitat For Bacilli, Justine M. Whitaker
Dissertations, Theses, and Masters Projects
No abstract provided.
Comparison Of Mussel-Bed Faunas At Blake Ridge And Florida Escarpment Seeps, Kathleen Elizabeth Knick
Comparison Of Mussel-Bed Faunas At Blake Ridge And Florida Escarpment Seeps, Kathleen Elizabeth Knick
Dissertations, Theses, and Masters Projects
No abstract provided.
Long Term Permanent Vegetation Plot Studies In The Matoaka Woods, Williamsburg, Virginia : Establishment And Initial Data Analysis Of Plots Established With The North Carolina Vegetation Survey Protocol, Resampling Of Single Circular Plots And A Comparison Of Results From North Carolina Vegetation Survey Protocol And Single Circular Plot Methods, Jacob Robert George Kribel
Dissertations, Theses, and Masters Projects
No abstract provided.
The Role Of Stress In Determining Community Structure: Effects Of Hypoxia On An Estuarine Epifaunal Community, Alessandra Sagasti
The Role Of Stress In Determining Community Structure: Effects Of Hypoxia On An Estuarine Epifaunal Community, Alessandra Sagasti
Dissertations, Theses, and Masters Projects
Community models predict the effects of stress on community structure and processes. I tested the Menge and Sutherland 1987 model in an estuarine epifaunal community experiencing low oxygen stress, termed hypoxia. Epifauna, animals living on the surfaces of substrates, are ecologically important in many estuaries where hypoxia occurs, yet little is known about the effects of hypoxia on these communities. Epifauna formed dense communities in the York River, a tributary of the Chesapeake Bay, USA, despite frequent hypoxia. Abundance and species composition was similar in two areas of the river, even though the downstream study area often experienced lower oxygen …
The Habitat Utilization Of Juvenile Hawksbill Sea Turtles (Eretmochelys Imbricata) At Buck Island Reef National Monument, St Croix, U.S Virgin Islands, Roy A. Pemberton
The Habitat Utilization Of Juvenile Hawksbill Sea Turtles (Eretmochelys Imbricata) At Buck Island Reef National Monument, St Croix, U.S Virgin Islands, Roy A. Pemberton
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
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.
Ecosystem Analysis Of Water Column Processes In The York River Estuary, Virginia: Historical Records, Field Studies And Modeling Analysis, Yongsik Sin
Dissertations, Theses, and Masters Projects
Analyses of EPA long-term datasets (1985--1994) combined with field studies and ecosystem model development were used to investigate phytoplankton and nutrient dynamics in the York River estuary. Analysis of the EPA dataset showed that algal blooms occurred during winter-spring followed by smaller summer blooms. Peak phytoplankton biomass during the winter-spring blooms occurred in the mid reach of the mesohaline zone whereas during the summer bloom it occurred in the tidal fresh-mesolialine transition zone. River discharge appears to be the major factor controlling the location and timing of the winter-spring blooms and the relative degree of potential nitrogen (N) and phosphorus …
Correspondence Between Environmental Gradients And The Assemblage Structure Of Littoral Fishes In The Tidal Portion Of Three Virginia Coastal Plain Rivers, Clifford Michael Wagner
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
Habitat Complexity As A Determinant Of Juvenile Blue Crab Survival, Jessica L. Schulman
Dissertations, Theses, and Masters Projects
No abstract provided.
Determination Of The Natal Origin And Genetic Stock Composition Of A Juvenile Feeding Population Of The Loggerhead Turtle (Caretta Caretta) In Chesapeake Bay, Jeffrey Worner Norrgard
Determination Of The Natal Origin And Genetic Stock Composition Of A Juvenile Feeding Population Of The Loggerhead Turtle (Caretta Caretta) In Chesapeake Bay, Jeffrey Worner Norrgard
Dissertations, Theses, and Masters Projects
No abstract provided.
Use Of A Landscape-Level Approach To Determine The Habitat Requirements Of The Yellow-Crowned Night-Heron, Nycticorax Violaceus, In The Lower Chesapeake Bay, Ellen L. Bentley
Use Of A Landscape-Level Approach To Determine The Habitat Requirements Of The Yellow-Crowned Night-Heron, Nycticorax Violaceus, In The Lower Chesapeake Bay, Ellen L. Bentley
Dissertations, Theses, and Masters Projects
No abstract provided.