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Full-Text Articles in Physical Sciences and Mathematics

The Relationship Between Reproduction And Mortality In Triploid Crassostrea Virginica: A Matter Of Economic Importance, Joseph L. Matt, Standish K. Allen Oct 2015

The Relationship Between Reproduction And Mortality In Triploid Crassostrea Virginica: A Matter Of Economic Importance, Joseph L. Matt, Standish K. Allen

Presentations

The goal of this project is to maximize survival for commercially produced triploid Crassostrea virginica oysters in Virginia. Over the last few years, commercial oyster growers in Virginia have reported significant mortality events of triploid oysters during the spring and summer months. The summer of 2014 was the worst yet, as growers across the state reported summer mortality, most severe on the Eastern shore and in some cases as high as 85% of the crop (Karen Hudson, personal communication). Surviving oysters from some of these mortality events were sent to the Virginia Institute of Marine Science and several of the …


Marine Debris & Microplastics: Sources & Solutions For Coastal Virginia, Center For Coastal Resources Management, Virginia Institute Of Marine Science Jul 2015

Marine Debris & Microplastics: Sources & Solutions For Coastal Virginia, Center For Coastal Resources Management, Virginia Institute Of Marine Science

Reports

Rivers & Coast is a periodic publication of the Center for Coastal Resources Management, Virginia Institute of Marine Science. The goal of Rivers & Coast is to keep readers well informed of current scientific understanding behind key environmental issues related to watershed rivers and coastal ecosystems of the Chesapeake Bay.


Living Shoreline Implementation: Challenges And Solutions, Center For Coastal Resources Management, Virginia Institute Of Marine Science Jul 2014

Living Shoreline Implementation: Challenges And Solutions, Center For Coastal Resources Management, Virginia Institute Of Marine Science

Reports

Rivers & Coast is a periodic publication of the Center for Coastal Resources Management, Virginia Institute of Marine Science. The goal of Rivers & Coast is to keep readers well informed of current scientific understanding behind key environmental issues related to watershed rivers and coastal ecosystems of the Chesapeake Bay.


New Guidance For Local Wetlands Boards, Center For Coastal Resources Management, Virginia Institute Of Marine Science Apr 2014

New Guidance For Local Wetlands Boards, Center For Coastal Resources Management, Virginia Institute Of Marine Science

Reports

Rivers & Coast is a periodic publication of the Center for Coastal Resources Management, Virginia Institute of Marine Science. The goal of Rivers & Coast is to keep readers well informed of current scientific understanding behind key environmental issues related to watershed rivers and coastal ecosystems of the Chesapeake Bay.


Fishes In Seagrass Habitats: Species Composition, Trophic Interactions, And Production, Kathryn L. Sobocinski Jan 2014

Fishes In Seagrass Habitats: Species Composition, Trophic Interactions, And Production, Kathryn L. Sobocinski

Dissertations, Theses, and Masters Projects

The value of habitats in terms of biological production is of interest to ecologists and resource managers. Seagrasses are a commonly occurring habitat type in shallow marine waters and have been shown to support high abundances of fish and invertebrates. In lower Chesapeake Bay, seagrasses grow in a shallow fringe in the subtidal zone. Although, ample evidence exists for the value of these habitats as foraging and rearing areas for a variety of organisms, the connectivity among species and the benefits derived from these habitats in terms of production have not been well described, especially for small, seasonally occurring finfishes. …


Impact Of Mercury Exposure On Birds And The Effect Of Molt On Mercury Depuration In Songbirds, Margaret Crossley Whitney Jan 2014

Impact Of Mercury Exposure On Birds And The Effect Of Molt On Mercury Depuration In Songbirds, Margaret Crossley Whitney

Dissertations, Theses, and Masters Projects

No abstract provided.


Thin-Layer Sediment Addition Of Dredge Material For Enhancing Marsh Resilience, Virginia Institute Of Marine Science Jan 2014

Thin-Layer Sediment Addition Of Dredge Material For Enhancing Marsh Resilience, Virginia Institute Of Marine Science

Reports

Building marsh elevations with sediment delivered from nearby dredging projects is a potentially valuable tool for creating, restoring, and maintaining coastal marshes, and may help slow or reverse losses of wetlands due to coastal development and sea-level rise (Woodhouse et al., 1972). . . .


Virginia Coastal And Ocean Resource Issues, Virginia Institute Of Marine Science Jan 2014

Virginia Coastal And Ocean Resource Issues, Virginia Institute Of Marine Science

Reports

Fisheries, aquaculture and marine recreation in Chesapeake Bay and the coastal ocean are important economic engines adding greatly to the economy of the Commonwealth of Virginia. Virginia’s commercial harvest ranks 3rd largest and 7th in total value nationwide. Research at the Virginia Institute of Marine Science (VIMS) shows that Virginia’s water-dependent resource-based industries, including commercial and recreational fisheries, shellfish aquaculture and recreational boating, annually generate $2.53 billion in sales and approximately $1.25–$1.5 billion in income, supporting over 20,000 jobs. . . .


Use Of Guidance To Preserve And Protect Wetlands, Center For Coastal Resources Management, Virginia Institute Of Marine Science Oct 2013

Use Of Guidance To Preserve And Protect Wetlands, Center For Coastal Resources Management, Virginia Institute Of Marine Science

Reports

Rivers & Coast is a periodic publication of the Center for Coastal Resources Management, Virginia Institute of Marine Science. The goal of Rivers & Coast is to keep readers well informed of current scientific understanding behind key environmental issues related to watershed rivers and coastal ecosystems of the Chesapeake Bay.


The Launch: Comprehensive Coastal Resource Management Plans For Local Governments, Center For Coastal Resources Management, Virginia Institute Of Marine Science Apr 2013

The Launch: Comprehensive Coastal Resource Management Plans For Local Governments, Center For Coastal Resources Management, Virginia Institute Of Marine Science

Reports

Rivers & Coast is a periodic publication of the Center for Coastal Resources Management, Virginia Institute of Marine Science. The goal of Rivers & Coast is to keep readers well informed of current scientific understanding behind key environmental issues related to watershed rivers and coastal ecosystems of the Chesapeake Bay.


Ecologically-Framed Mercury Database, Exposure Modeling And Risk/Benefit Communication To Lower Chesapeake Bay Fish Consumers, Xiaoyu Xu Jan 2013

Ecologically-Framed Mercury Database, Exposure Modeling And Risk/Benefit Communication To Lower Chesapeake Bay Fish Consumers, Xiaoyu Xu

Dissertations, Theses, and Masters Projects

Mercury concentrations and determinants of mercury accumulation were examined for ten finfish species from the lower Chesapeake Bay and its tributaries. None of the sampled fish had total mercury concentrations approaching the U.S. EPA human health screening value. Mercury concentrations in different fish species generally increased with increasing delta 15N, but not delta 13C, suggesting that trophic position, but not dietary carbon source was a dominant determinant. A methylmercury biomagnification model was built to estimate a food web magnification factor of approximately 10-fold increase per trophic level in Chesapeake Bay. Based on otolith strontium-calcium ratios, Atlantic croaker inhabiting less saline …


Modeling The Formation Of Periodic Hypoxia In Partially Mixed Estuaries And Its Response To Oligotrophication And Climate Change, Samuel J. Lake Jan 2013

Modeling The Formation Of Periodic Hypoxia In Partially Mixed Estuaries And Its Response To Oligotrophication And Climate Change, Samuel J. Lake

Dissertations, Theses, and Masters Projects

The development of hypoxia represents one of the most common and ecologically detrimental effects of anthropogenic nutrient enrichment in coastal marine ecosystems. Due to the physiological importance of oxygen as a key component of metabolic processes, the development and persistence of hypoxia can reduce the distribution of important species, modify food webs, decrease diversity and richness, and sub-lethally affect growth and reproductive rates. While many recent studies have focused on the global increase in hypoxia and highlighted the need for nutrient reduction strategies, some key processes associated with hypoxia remain understudied. of particular importance is the resolution of the major …


Habitat And Fish Population Dynamics: Advancing Stock Assessments Of Highly Migratory Species, Patrick D. Lynch Jan 2013

Habitat And Fish Population Dynamics: Advancing Stock Assessments Of Highly Migratory Species, Patrick D. Lynch

Dissertations, Theses, and Masters Projects

Fisheries sustainability is inherently linked to an understanding of the population-level effects of fishing. With an accurate characterization of historical fish and fishery dynamics, management agencies are more equipped to create regulations that sustain fishery resources over the long term. The overarching goal of this dissertation is to contribute to the advancement of fisheries stock assessment and promote resource sustainability. My research focused on highly migratory species (HMS), particularly fishes that reside in the open ocean. These species constitute some of the highest valued global fisheries; however, numerous factors compromise HMS stock assessment and management. These challenges are fully described …


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 …


Living Shorelines Policy: The Integration Of Shoreline Management And Planning, Center For Coastal Resources Management, Virginia Institute Of Marine Science Apr 2012

Living Shorelines Policy: The Integration Of Shoreline Management And Planning, Center For Coastal Resources Management, Virginia Institute Of Marine Science

Reports

Rivers & Coast is a periodic publication of the Center for Coastal Resources Management, Virginia Institute of Marine Science. The goal of Rivers & Coast is to keep readers well informed of current scientific understanding behind key environmental issues related to watershed rivers and coastal ecosystems of the Chesapeake Bay.


Evaluating Persistent Organic Pollutants (Pops) And Mercury In The West Antarctic Peninsula (Wap) Food Web, With A Focus On Antarctic Fur Seals (Arctocephalus Gazella), Emily K. Brault Jan 2012

Evaluating Persistent Organic Pollutants (Pops) And Mercury In The West Antarctic Peninsula (Wap) Food Web, With A Focus On Antarctic Fur Seals (Arctocephalus Gazella), Emily K. Brault

Dissertations, Theses, and Masters Projects

No abstract provided.


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 …


Virginia's Comprehensive Wetlands Program Plan, Center For Coastal Resources Management, Virginia Institute Of Marine Science Jul 2011

Virginia's Comprehensive Wetlands Program Plan, Center For Coastal Resources Management, Virginia Institute Of Marine Science

Reports

Rivers & Coast is a periodic publication of the Center for Coastal Resources Management, Virginia Institute of Marine Science. The goal of Rivers & Coast is to keep readers well informed of current scientific understanding behind key environmental issues related to watershed rivers and coastal ecosystems of the Chesapeake Bay.


Coastal Resource Management Planning, Center For Coastal Resources Management, Virginia Institute Of Marine Science Apr 2011

Coastal Resource Management Planning, Center For Coastal Resources Management, Virginia Institute Of Marine Science

Reports

Rivers & Coast is a periodic publication of the Center for Coastal Resources Management, Virginia Institute of Marine Science. The goal of Rivers & Coast is to keep readers well informed of current scientific understanding behind key environmental issues related to watershed rivers and coastal ecosystems of the Chesapeake Bay.


The Effects Of Hypoxia On Macrobenthic Production And Function In The Lower Rappahannock River, Chesapeake Bay, Usa, S. Kersey Sturdivant Jan 2011

The Effects Of Hypoxia On Macrobenthic Production And Function In The Lower Rappahannock River, Chesapeake Bay, Usa, S. Kersey Sturdivant

Dissertations, Theses, and Masters Projects

Human development has eroded Chesapeake Bay's health, resulting in an increase in the extent and severity of hypoxia (≤2 mg O2 l-1). The Bay's hypoxic zones have an adverse affect on community function and secondary production of macrobenthos. The production of macrobenthos is important as these fauna link energy transfer from primary consumers to epibenthic predators and demersal fish, and serve as the foremost pathway that carbon is recycled out of the sediment. Additionally, bioturbation, an essential macrobenthic function that causes the displacement and mixing of sediment particles, increases the quality of marine sediments. In the marine environment bioturbation is …


Net Microbial Activity, Vegetation Dynamics, And Ecosystem Function In Created And Natural Palustrine Forested Wetlands In Southeastern Virginia, Usa, Christian A. Hauser Jan 2011

Net Microbial Activity, Vegetation Dynamics, And Ecosystem Function In Created And Natural Palustrine Forested Wetlands In Southeastern Virginia, Usa, Christian A. Hauser

Dissertations, Theses, and Masters Projects

No abstract provided.


Derelict Crab Pots In The Chesapeake Bay, Center For Coastal Resources Management, Virginia Institute Of Marine Science Oct 2010

Derelict Crab Pots In The Chesapeake Bay, Center For Coastal Resources Management, Virginia Institute Of Marine Science

Reports

Rivers & Coast is a periodic publication of the Center for Coastal Resources Management, Virginia Institute of Marine Science. The goal of Rivers & Coast is to keep readers well informed of current scientific understanding behind key environmental issues related to watershed rivers and coastal ecosystems of the Chesapeake Bay.


Integrated Shoreline Management Decision Tree For Untreated Shorelines, Center For Coastal Resources Management, Virginia Institute Of Marine Science Jul 2010

Integrated Shoreline Management Decision Tree For Untreated Shorelines, Center For Coastal Resources Management, Virginia Institute Of Marine Science

Reports

Rivers & Coast is a periodic publication of the Center for Coastal Resources Management, Virginia Institute of Marine Science. The goal of Rivers & Coast is to keep readers well informed of current scientific understanding behind key environmental issues related to watershed rivers and coastal ecosystems of the Chesapeake Bay.


Copepod Carcasses, Mortality And Population Dynamics In The Tributaries Of The Lower Chesapeake Bay, David Thomas. Elliott Jan 2010

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 …


Bioavailability Of Biosolids- And Consumer Product-Associated Polybrominated Diphenyl Ether (Pbde) Flame Retardants To Terrestrial Invertebrates, Michael O. Gaylor Jan 2010

Bioavailability Of Biosolids- And Consumer Product-Associated Polybrominated Diphenyl Ether (Pbde) Flame Retardants To Terrestrial Invertebrates, Michael O. Gaylor

Dissertations, Theses, and Masters Projects

The primary objectives of this research were therefore to evaluate polybrominated diphenyl ether (PBDE) bioavailability to ecologically distinct soil invertebrates exposed to Penta-BDE-treated consumer polyurethane foam (PUF) products and biosolid products with incurred PBDEs. In laboratory bioassays, earthworms (Eisenia fetida) bioaccumulated SigmaPBDEs (47+99+100+183) up to 11,000 mug/kg lipid after 28 days from a mixture of artificial soil and anaerobically-digested sludge biosolid (ADB). Earthworms also bioaccumulated SigmaPBDEs (47+99+100+153+154+183) up to 13,500 and 838,000 mug/kg lipid after 28 d from a mixture of artificial soil and composted sludge biosolid (CB) and Penta-BDE-spiked artificial soil (SAS), respectively. No previous lab studies on bioaccumulation …


Effects Of Habitat Quality On Secondary Production In Shallow Estuarine Waters And The Consequences For The Benthic-Pelagic Food Web, David James Gillett Jan 2010

Effects Of Habitat Quality On Secondary Production In Shallow Estuarine Waters And The Consequences For The Benthic-Pelagic Food Web, David James Gillett

Dissertations, Theses, and Masters Projects

Anthropogenic degradation of coastal and estuarine habitats is an ongoing problem facing scientists, natural resource mangers, and the general public. Decreases in habitat quality produce relatively predictable changes in the structure and composition of macrobenthic communities and it has traditionally been assumed that the ecosystem functions of the community change as well. In Chesapeake Bay, the most pervasive cause for the degradation of benthic habitats is the excessive inputs of nutrients that lead to eutrophication and the accumulation of organic matter in the system. Working within this framework, a study was conducted investigating changes in macrobenthic (i.e., secondary) production along …


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 …


Assessing The Functional Status Of Created Wetlands In Eastern Virginia Via A Soil And Vegetative Developmental Trajectory, Sara Elizabeth Kreisel Jan 2010

Assessing The Functional Status Of Created Wetlands In Eastern Virginia Via A Soil And Vegetative Developmental Trajectory, Sara Elizabeth Kreisel

Dissertations, Theses, and Masters Projects

No abstract provided.


Shallow Water Dredging, Center For Coastal Resources Management, Virginia Institute Of Marine Science Jan 2010

Shallow Water Dredging, Center For Coastal Resources Management, Virginia Institute Of Marine Science

Reports

Rivers & Coast is a periodic publication of the Center for Coastal Resources Management, Virginia Institute of Marine Science. The goal of Rivers & Coast is to keep readers well informed of current scientific understanding behind key environmental issues related to watershed rivers and coastal ecosystems of the Chesapeake Bay


Persistent Organic Pollutants(Pops) As Tracers Of Environmental Change And Antarctic Seabird Ecology, Heidi N. C. Geisz Jan 2010

Persistent Organic Pollutants(Pops) As Tracers Of Environmental Change And Antarctic Seabird Ecology, Heidi N. C. Geisz

Dissertations, Theses, and Masters Projects

Antarctic seabirds including Adelie penguins (Pygoscelis adeliae), south polar skuas (Catharacta maccormicki), southern giant petrels (Macronectes gigantus) are high trophic level predators that accumulate persistent organic pollutants (POPs) present in the food webs in which they forage. Little is known about the levels of POPs in some Antarctic organisms (e.g. southern giant petrels), as well as the long-term trends of POPs in the Antarctic ecosystem. Samples from all three seabird species were collected post mortem, including eggs, from the Western Antarctic Peninsula (WAP) and in the Ross Sea throughout the austral summer breeding seasons of 2004--2006. The samples were analyzed …