Life Sciences Commons^™

Examining The Effect Of Interstitial Space On Eastern Oysters (Crassostrea Virginica): Applications Of Photogrammetry And Three-Dimensional Modeling, Bailie Lavan

Masters Theses, 2010-2019

Global oyster populations have decreased by as much as 99% in the past century. Oysters are known ecosystem engineers, providing benthic habitat for macrofauna, linking benthic and pelagic food webs, improving water quality, and mitigating shoreline erosion. Restoration efforts are critical in re-establishing native oyster populations. In the Chesapeake Bay, where oyster loss is primarily due to severe over harvest, artificial substrates with geometric shapes are widely used in restoration efforts. However, natural oyster reefs form emergent shapes with a high degree of aggregation and many interstitial spaces (three-dimensional volumetric spaces between oysters within a reef). The lack of interstitial …

Assessing Populations Of Eastern Brook Trout (Salvelinus Fontinalis) Above And Below Waterfalls In Mountain Streams Of Virginia, Hannah Eisemann Macmillan

Masters Theses, 2010-2019

Anthropogenically driven factors, such as increasing temperature and sediment in valley streams, acidification of mountain streams, and the introduction of non-native trout, are restricting habitat suitable for healthy populations of eastern brook trout (Salvelinus fontinalis) throughout their native Appalachian range. Brook trout are important as predators of insects in mountain streams and as a favorite of anglers. It is crucial that remaining populations in sustainable habitats be identified and preserved. Waterfalls are geologic knickpoints preventing base-level lowering that create unique, stable landscapes above them, which may alleviate the temperature-productivity/acidity “habitat squeeze” for populations of brook trout and could …

Urban Stream Restoration: An Evaluation Of Material Processing And Conveyance Channels, Madeline Berg

Masters Theses, 2010-2019

Stream restoration is gaining popularity in the Mid - Atlantic region to offset impacts from urbanization. Increased levels of impervious surfaces, decreased vegetation along banks, and changes in water flow patterns make urban stream ecosystems flashy and result in high erosion rates, increasing the amount of nutrients entering the Chesapeake Bay. Different restoration practices can play a large role in the amount of nutrients and organic matter leaving a stream and the amount of habitat that is present in-stream.

Due to the recent interest in stream restoration as a tool to help the health of the Chesapeake Bay, this study …

Potential Benefits Of Restored Riparian Zones In An Agricultural Matrix For Bat Communities, Matthew T. Harris

Masters Theses, 2010-2019

Riparian buffers planted within agricultural matrices for wildlife conservation are expected to support numerous taxa, but a lack of empirical testing has limited evaluation of these practices. It is imperative that biologists and land managers understand how current conservation practices impact bats so that the ecosystem services provided by bats are maintained as farming practices continue to intensify in regions dominated by agriculture. This study evaluates the effects of planted riparian buffers along streams in an agricultural matrix by comparing acoustic bat activity along streams in active cattle pasture with activity at streams where riparian buffers have been planted. Forest …

Efficacy Of Magnesium Enriched Artificial Substrate For Oyster Restoration, Matthew Elder

Masters Theses, 2010-2019

The eastern oyster, Crassostrea virginica, is a keystone species that has undergone a large (> 95%) population decline due to overharvest, pollution, and disease. Restoration efforts focus on alternative larval attachment substrates such as concrete, to supplement the loss of natural oyster shell. Magnesium is a component of bivalve shells and its presence in the environment has shown to be important to the growth of mussels, but the same relationship has not been studied in oysters. Assuming that magnesium can be assimilated from the substrate on which the organism is growing, or that ions of magnesium are leached into …

The Effect Of Calcium In Artificial Substrates For Oyster Restoration: Implications For The Mitigation Of Oyster Population Decline, Jessie Mandirola

Masters Theses, 2010-2019

Oyster populations in the Chesapeake Bay have declined by 99% over the past 150 years due to overharvesting, disease, ocean acidification, and poor water quality. Restoration efforts are needed to reestablish native oyster populations. Current restoration efforts utilize natural oyster shells but these methods are expensive and unsustainable. Therefore, restoration is starting to use artificial substrates instead. Concrete has been successfully used in previous research; spat will attach and oysters will grow. However, there is a lack of knowledge about how the composition of concrete effects oyster larval recruitment. We tested concrete made with limestone sand (“special concrete”) to increase …

Vertical Movement Of The Endangered James Spinymussel (Pleurobema Collina) And The Notched Rainbow Mussel (Villosa Constricta) In Response To Floods At Different Temperatures And Substrates: Implications For Conservation And Management, Dorottya Boisen

Masters Theses, 2010-2019

Freshwater mussels are keystone species in their ecosystems, improving water and substrate quality for other organisms while they are alive, and buffering stream pH and providing shelter with their shells after they die. Approximately 70% of all freshwater mussel species are endangered globally. The James Spinymussel (Pleurobema collina) is a critically endangered species that lives in disparate tributaries of the James River of Virginia. Like other freshwater mussels, they have a cryptic appearance and behavior, making them difficult to find and therefore, to study and conserve. Previous studies indicate a higher percentage of mussels are surfaced during their …

Using Capture-Mark-Recapture Techniques To Estimate Detection Probabilities & Fidelity Of Expression For The Critically Endangered James Spinymussel (Pleurobema Collina)., Alaina C. Esposito

Masters Theses, 2010-2019

The critically endangered James Spinymussel (Pleurobema collina) is a species of freshwater mussel endemic to Virginia’s James and Dan River basins. In the last 20 years, P. collina has experienced a substantial decline in numbers and currently occupies approximately 10% of its original habitat; however, little information is known about this species to assist in conservation. A 230-meter reach of transitional habitat in Swift Run was selected for repeat observations to estimate detection probabilities using a Capture-Mark-Recapture framework. In June 2014, visual scouting began to locate and tag P. collina (including other mussels in the community) with PIT …