Digital Commons Network^™

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 …

Analysis Of Edna To Assess Effects Of Water Quality On Freshwater Fungal Diversity In A Virginia Coastal Watershed, Lauren French

Undergraduate Honors Theses

Freshwater fungi comprise a phylogenetically and functionally diverse group which contributes to wide-ranging ecosystem processes in aquatic systems. Saprotrophic fungi convert detritus into nutrient-rich food sources for fish and invertebrates, whereas pathogenic and parasitic fungi can cause disease and population declines of other aquatic organisms. With their diverse and important roles, changes in freshwater fungal community structure may have far-reaching impacts on ecosystems. To understand how natural and anthropogenic stressors to freshwater systems impact fungal-mediated ecosystem processes, a greater understanding of the taxonomic and functional composition of freshwater fungal communities is needed. We assessed relationships among freshwater habitat types, water …

Marine Heatwaves In The Chesapeake Bay, Piero L. F. Mazzini, Cassia Pianca

VIMS Articles

Prolonged events of anomalously warm sea water temperature, or marine heatwaves (MHWs), have major detrimental effects to marine ecosystems and the world's economy. While frequency, duration and intensity of MHWs have been observed to increase in the global oceans, little is known about their potential occurrence and variability in estuarine systems due to limited data in these environments. In the present study we analyzed a novel data set with over three decades of continuous in situ temperature records to investigate MHWs in the largest and most productive estuary in the US: the Chesapeake Bay. MHWs occurred on average twice per …

Living Shorelines Achieve Functional Equivalence To Natural Fringe Marshes Across Multiple Ecological Metrics, Robert Isdell, Donna M. Bilkovic, Amanda Guthrie, Molly Mitchell, Randolph M. Chambers, Matthias Leu, Carl Hershner

VIMS Articles

Nature-based shoreline protection provides a welcome class of adaptations to promote ecological resilience in the face of climate change. Along coastlines, living shorelines are among the preferred adaptation strategies to both reduce erosion and provide ecological functions. As an alternative to shoreline armoring, living shorelines are viewed favorably among coastal managers and some private property owners, but they have yet to undergo a thorough examination of how their levels of ecosystem functions compare to their closest natural counterpart: fringing marshes. Here, we provide a synthesis of results from a multi-year, large-spatial-scale study in which we compared numerous ecological metrics (including …

Massive Upland To Wetland Conversion Compensated For Historical Marsh Loss In Chesapeake Bay, Usa, Nathalie W. Schieder, David C. Walters, Matthew L. Kirwan

VIMS Articles

Sea level rise leads to coastal transgression, and the survival of ecosystems depends on their ability to migrate inland faster than they erode and submerge. We compared marsh extent between nineteenth-century maps and modern aerial photographs across the Chesapeake Bay, the largest estuary in North America, and found that Chesapeake marshes have maintained their spatial extent despite relative sea level rise rates that are among the fastest in the world. In the mapped region (i.e., 25% of modern Chesapeake Bay marshland),94 km2of marsh was lost primarily to shoreline erosion,whereas 101 km2of marsh was created by upland drowning.Simple projections over the …

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 …

A Synergistic Approach For Evaluating Climate Model Output For Ecological Applications, Rochelle Cavanaugh, Ej Murphy, Et Al, Walker O. Smith Jr., Et Al

VIMS Articles

Increasing concern about the impacts of climate change on ecosystems is prompting ecologists and ecosystem managers to seek reliable projections of physical drivers of change. The use of global climate models in ecology is growing, although drawing ecologically meaningful conclusions can be problematic. The expertise required to access and interpret output from climate and earth system models is hampering progress in utilizing them most effectively to determine the wider implications of climate change. To address this issue, we present a joint approach between climate scientists and ecologists that explores key challenges and opportunities for progress. As an exemplar, our focus …

Atlantic Coast And Inner Shelf, David E. Krantz, Carl H. Hobbs Iii, Geoffrey L. Wikel

VIMS Books and Book Chapters

The continental margin of Virginia, and of North America more broadly, is the physical transition from the high elevation of the continent to the low of the ocean basin. This transition was created as rifting pulled apart the ancient supercontinent Pangaea to create the Atlantic Ocean basin. Tectonic forces fractured and stretched the bedrock to create a stair-step ramp that subsequently would be mantled with sediment built up by erosion and transport off the continent.

The Coastal Plain and Continental Shelf of Virginia are contiguous and discrete physiographic provinces of the continental margin delimited by the present elevation of sea …

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 …

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, …

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

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 …

York River Water Budget, Carl Hershner, Molly Mitchell, Donna Marie Bilkovic, Julie D. Herman, Center For Coastal Resources Management, Virginia Institute Of Marine Science

Reports

No abstract provided.

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

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

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 …

Mercury Levels In Newly Independent Songbirds, Anne Moire Condon

Dissertations, Theses, and Masters Projects

No abstract provided.

Broad Spatial Trends In Osprey Provisioning, Reproductive Success, And Population Growth Within Lower Chesapeake Bay, Kenneth Andrew Glass

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

Dissertations, Theses, and Masters Projects

No abstract provided.

The Crest, Summer 2006, Virginia Institute Of Marine Science

Reports

Table of Contents:

• Menhaden research
• Sea Grant renews effort to manage cownose rays
• Food-web study aids management of biodiversity
• Horodysky throws light on fish vision Research reveals lobsters avoid sick neighbors
• New faculty brushes aside disciplinary boundaries
• Research helps created wetlands come to life
• Miselis chosen as Foster Scholar
• Wetlands workshop promotes informed management
• VIMS bestows 2005 Awards
• Duffy and Lipcius win Leopold Fellowships
• Alum coaches high school team to national recognition
• VIMS alumna receives prestigious national award
• Lucy wins Hutchinson conservation award
• Newsbriefs

Development Of A Tidal Wetland Inventory And Assessment For York River, Virginia Watershed, Center For Coastal Resources Management, Virginia Institute Of Marine Science

Reports

As part of the Chesapeake 2000 agreement, the Commonwealth of Virginia pledged to a wetland policy of no net-loss. Through conscientious resource protection and management, Virginia’s non-tidal and tidal wetland permit programs, administered by the Virginia Department of Environmental Quality (DEQ) and The Virginia Marine Resources Commission (VMRC) respectfully, are committed to reaching this goal. In order to assist these agencies in realizing no-net loss of wetlands, the availability of baseline data is essential in defining our existing resources and is the basis from which future status and trends can be evaluated along with the effectiveness of permitting and management …

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.

Bioreactivity Of Estuarine Dissolved Organic Matter: A Combined Geochemical And Microbiological Approach, Sl Mccallister, Je Bauer, Elizabeth A. Canuel

VIMS Articles

An integrated multidisciplinary study utilizing geochemical and microbial ecological approaches was conducted to characterize the origins, chemical nature, and quantities of dissolved and particulate organic matter (OM) utilized by heterotrophic bacteria in a temperate estuary. C: N, stable isotope (delta C-13), and lipid biomarker analyses revealed differences in the inferred reactivity of autochthonous versus allochthonous OM sources. Isotopic comparison of OM size fractions and bacterial nucleic acids suggests that high-molecular-weight dissolved OM (DOM) is consistently linked to bacterial biomass synthesis along the estuarine salinity gradient. Polyunsaturated fatty acids (as percent of total fatty acids, FA) were a reliable predictor of …

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

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.

Use Of Remote Sensing To Identify Essential Habitat For Aeschynomene Virginica (L) Bsp, A Threatened Tidal Freshwater Wetland Plant, Elizabeth M. Mountz

Dissertations, Theses, and Masters Projects

No abstract provided.

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.

The Crest, Summer 1999, Virginia Institute Of Marine Science

Reports

Table of Contents:

• New Research Aquarium System
• Finfish Aquaculture at VIMS
• Virginia Creates State Research Reserve System
• Pollution-Laden Sediments In Constant Flux
• Survey of Mid-Atlantic Sea Scallop Closed Areas
• Pfiesteria Update
• New Computer Program Helps Planners Balance Growth, Protection
• Virginia Sea Grant to Administer Commercial Fishery Resource Program
• VIMS Stranded Sea Turtle Project Underway Coastal Sediments Offer Clues to Climate Change, Pollution
• Seemingly Barren Habitat Proves Vital for Economically Important Virginia Fish (juvenile flounder)

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.