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Full-Text Articles in Life Sciences
Environmentally-Determined Production Frontiers And Lease Utilization In Virginia's Eastern Oyster Aquaculture Industry, Jennifer Beckensteiner, Andrew M. Scheld, Pierre St-Laurent, Marjorie A.M. Friedrichs, David M. Kaplan
Environmentally-Determined Production Frontiers And Lease Utilization In Virginia's Eastern Oyster Aquaculture Industry, Jennifer Beckensteiner, Andrew M. Scheld, Pierre St-Laurent, Marjorie A.M. Friedrichs, David M. Kaplan
VIMS Articles
During the last decade, oyster aquaculture has rebounded in Virginia and has been associated with an increase in subaqueous leased area. Production levels remain historically low, however, and many leases are thought to be underutilized. This study uses a novel approach leveraging high-resolution environmental data to evaluate lease utilization and identify constraints on aquaculture development. Stochastic Frontier Analysis (SFA) and Data Envelopment Analysis (DEA) were used to define environmentally-determined production frontiers, i.e. production possibilities based on empirical observations of aquaculture production, available space, and environmental conditions. Both methods estimated Lease Capacity Utilization (LCU, from 0 to 1) for leases producing …
Large Projected Population Loss Of A Salt Marsh Bivalve (Geukensia Demissa) From Sea Level Rise, Robert Isdell, Donna M. Bilkovic, Carlton Hershner
Large Projected Population Loss Of A Salt Marsh Bivalve (Geukensia Demissa) From Sea Level Rise, Robert Isdell, Donna M. Bilkovic, Carlton Hershner
VIMS Articles
Salt marshes and their inhabitants are being displaced by climate change and human development along the coastline. One inhabitant, the ribbed mussel (Geukensia demissa), forms a mutualistic relationship with smooth cordgrass, Sporobolus alterniflorus, along the US Atlantic Coast. Ribbed mussels stabilize the marsh, remove particulate matter from the water column, and promote denitrification, thereby improving local water quality. To quantify the potential effects of SLR on ribbed mussel abundance and resulting impacts on water quality functions, we compared the current and projected future (2050) spatial distributions of ribbed mussels in Chesapeake Bay assuming an intermediate SLR for …
Sensitivity Of A Shark Nursery Habitat To A Changing Climate, Daniel Crear, Robert Latour, Marjorie A.M. Friedrichs, Pierre St-Laurent, Kevin C. Weng
Sensitivity Of A Shark Nursery Habitat To A Changing Climate, Daniel Crear, Robert Latour, Marjorie A.M. Friedrichs, Pierre St-Laurent, Kevin C. Weng
VIMS Articles
Nursery area habitats such as estuaries are vital for the success of many fish populations. Climate change is altering conditions in these areas, which can thus impact the availability of suitable nursery habitat. The sandbar shark Carcharhinus plumbeus uses Chesapeake Bay (USA) as a nursery habitat during the summer months from birth up to 10 yr of age. To assess the impacts of climate change on juvenile sandbar sharks, we developed a habitat model using longline data collected from a fishery-independent survey within Chesapeake Bay. With this model, we projected contemporary and future distributions of suitable habitat for juvenile sandbar …
Restoration Of Seagrass Habitat Leads To Rapid Recovery Of Coastal Ecosystem Services, Robert J. Orth, Jonathan S. Lefcheck, Karen S. Mcglathery, Lillian Aoki, Mark Luckenbach, Kenneth A. Moore, Matthew P.J. Oreska, Richard A. Snyder, David J. Wilcox, Bo Lusk
Restoration Of Seagrass Habitat Leads To Rapid Recovery Of Coastal Ecosystem Services, Robert J. Orth, Jonathan S. Lefcheck, Karen S. Mcglathery, Lillian Aoki, Mark Luckenbach, Kenneth A. Moore, Matthew P.J. Oreska, Richard A. Snyder, David J. Wilcox, Bo Lusk
VIMS Articles
There have been increasing attempts to reverse habitat degradation through active restoration, but few largescale successes are reported to guide these efforts. Here, we report outcomes from a unique and very successful seagrass restoration project: Since 1999, over 70 million seeds of a marine angiosperm, eelgrass (Zostera marina), have been broadcast into mid-western Atlantic coastal lagoons, leading to recovery of 3612 ha of seagrass. Well-developed meadows now foster productive and diverse animal communities, sequester substantial stocks of carbon and nitrogen, and have prompted a parallel restoration for bay scallops (Argopecten irradians). Restored ecosystem services are approaching historic levels, but we …
Role Of Habitat And Predators In Maintaining Functional Diversity Of Estuarine Bivalves, Cassandra N. Glaspie, Rochell D. Seitz
Role Of Habitat And Predators In Maintaining Functional Diversity Of Estuarine Bivalves, Cassandra N. Glaspie, Rochell D. Seitz
VIMS Articles
Habitat loss is occurring rapidly in coastal systems worldwide. In Chesapeake Bay, USA, most historical oyster reefs have been decimated, and seagrass loss is expected to worsen due to climate warming and nutrient pollution. This loss of habitat may result in declining diversity, but whether diversity loss will equate to loss in ecosystem function is unknown. A bivalve survey was conducted in a variety of habitat types (seagrass, oyster shell, shell hash, coarse sand, detrital mud) in 3 lower Chesapeake Bay sub-estuaries from spring 2012 through summer 2013 to examine the correlation between bivalve densities, habitat type, habitat volume (of …
Long-Distance Dispersal Potential In A Marine Macrophyte, Mc Harwell, R J. Orth
Long-Distance Dispersal Potential In A Marine Macrophyte, Mc Harwell, R J. Orth
VIMS Articles
Plant populations have long been noted to migrate faster than predicted based on their life history and seed dispersal characteristics (i.e., Reid's paradox of rapid plant migration). Although precise mechanisms to account for such phenomena are not fully known for all plant species, a combination of theoretical and empirically driven mechanisms often resolves this paradox. Here, we couple a series of direct and indirect field and laboratory exercises on one marine macrophyte, Zostera marina L. (eelgrass), to measured distances between new patches and established beds in order to elucidate the longdistance dispersal and colonization potential of this marine seagrass. Detached, …
Seed Dispersal In A Marine Macrophyte - Implications For Colonization And Restoration, R J. Orth, Mark Luckenbach, Ken Moore
Seed Dispersal In A Marine Macrophyte - Implications For Colonization And Restoration, R J. Orth, Mark Luckenbach, Ken Moore
VIMS Articles
No abstract provided.
Effects Of Perkinsus Marinus Infection In The Eastern Oyster, Crassostrea Virginica: Ii. Disease Development And Impact On Growth Rate At Different Salinities, Kennedy T. Paynter, Eugene M. Burreson
Effects Of Perkinsus Marinus Infection In The Eastern Oyster, Crassostrea Virginica: Ii. Disease Development And Impact On Growth Rate At Different Salinities, Kennedy T. Paynter, Eugene M. Burreson
VIMS Articles
In order to assess the impact of Perkinsus marinus infection on oyster growth and mortality, oysters were raised in floating rafts at six sites around Chesapeake Bay. The sites were comprised of two low salinity sites (8-10%0), two moderate salinity (12-15%0) sites and two high salinity sites (16-20%0). Oyster growth was monitored biweekly along with various water qualities including temperature and salinity. Condition index was measured monthly and disease diagnosis was perfonned bimonthly. Oyster growth was initially greatest at the high salinity sites but was subsequently retarded by Perkinsus infection at both the moderate and high salinity sites (where the …
Susceptibility Of Diploid And Triploid Pacific Oysters, Crassostrea Gigas (Thunberg, 1793) And Eastern Oysters, Crassostrea Virginica (Gmelin, 1791), To Perkinsus Marinus, Judith A. Meyers, Eugene M. Burreson, Bruce J. Barber, Roger L. Mann
Susceptibility Of Diploid And Triploid Pacific Oysters, Crassostrea Gigas (Thunberg, 1793) And Eastern Oysters, Crassostrea Virginica (Gmelin, 1791), To Perkinsus Marinus, Judith A. Meyers, Eugene M. Burreson, Bruce J. Barber, Roger L. Mann
VIMS Articles
The susceptibility of Pacific oysters, Crassostrea gigas, to the oyster parasite Perkinsus marinus was compared with that of eastern oysters, Crassostrea virginica, in two separate experiments. Experiments were conducted in flow-through seawater systems with quarantined effluent. Oysters were challenged by addition of infective P. marinus. In the first experiment, which used only diploid oysters, 40% of C. gigas became infected with P. marinus after 83 days compared to 100% of C. virginica. In the second experiment, which examined susceptibility of diploid and triploid individuals of both species, prevalence was high in all groups after 60 days. In …
Effects Of Perkinsus Marinus Infection In The Eastern Oyster, Crassostrea Virginica: I. Susceptibility Of Native And Msx-Resistant Stocks, Eugene Burreson
Effects Of Perkinsus Marinus Infection In The Eastern Oyster, Crassostrea Virginica: I. Susceptibility Of Native And Msx-Resistant Stocks, Eugene Burreson
VIMS Articles
A selective breeding program was implemented to attempt to decrease the disease susceptibility of the eastern oyster, Crassostrea virginica, to Perkinsus marinus. Six oyster strains were spawned and the progeny exposed to Haplosporidium nelsoni (MSX) and P. marinus in the lower Chesapeake Bay. Three strains, a Delaware Bay MSX-resistant strain, a Delaware Bay native strain, and a Mobjack Bay native strain (lower Chesapeake Bay) were exposed for three years (1988-90); three other strains, a separate Delaware Bay MSX-resistant strain, a lower James River native strain (lower Chesapeake Bay) and a susceptible control strain, were exposed for two years (1989-90). …