Open Access. Powered by Scholars. Published by Universities.®
- Discipline
Articles 1 - 20 of 20
Full-Text Articles in Life Sciences
Design And Redesign Of A Bottom Trawl Survey In Chesapeake Bay, Usa, Robert J. Latour, James Gartland, Christopher F. Bonzek
Design And Redesign Of A Bottom Trawl Survey In Chesapeake Bay, Usa, Robert J. Latour, James Gartland, Christopher F. Bonzek
VIMS Articles
Fisheries-independent surveys that reliably sample a broad size range of exploited and ecologically important species provide valuable data in support of fisheries management and ecosystem science. The operational consistency of surveys over time and space is fundamental to the interpretation of data in the contexts of population dynamics processes, community interactions, policy impacts, and environmental forcing. However, the need to maintain historic sampling protocols over extended time periods limits the utilization of new technologies that could lead to improved data collection. Survey vessel replacements also become inevitable as the maturity of sampling programs becomes multidecadal. This case study describes the …
Effects Of Food Limitation On Growth, Body Condition And Metabolic Rates Of Non-Native Blue Catfish, Vaskar Nepal, Mary C. Fabrizio, Richard Brill
Effects Of Food Limitation On Growth, Body Condition And Metabolic Rates Of Non-Native Blue Catfish, Vaskar Nepal, Mary C. Fabrizio, Richard Brill
VIMS Articles
Establishment and range expansion of non-native species in novel habitats depend on their energetic requirements and food availability. Knowledge of growth and metabolic rates of non-native fishes at various food levels is particularly critical to inform models that assess their invasion potential. We compared growth rates, body condition and metabolic rates of juvenile blue catfish (Ictalurus furcatus), an invasive species in many lakes, coastal rivers and estuaries throughout the Eastern USA, at three ration levels: ad libitum (3.5% of fish body mass/d), two-third ad libitum and one-third ad libitum. All fish survived the entire duration of the experiment (4 months) …
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 …
Contemporary And Future Distributions Of Cobia, Rachycentron Canadum, Dp Crear, Be Watkins, Vs Saba, Je Graves, Dr Jensen, Aj Hobday, Kevin C. Weng
Contemporary And Future Distributions Of Cobia, Rachycentron Canadum, Dp Crear, Be Watkins, Vs Saba, Je Graves, Dr Jensen, Aj Hobday, Kevin C. Weng
VIMS Articles
Climate change has influenced the distribution and phenology of marine species, globally. However, knowledge of the impacts of climate change is lacking for many species that support valuable recreational fisheries. Cobia (Rachycentron canadum) are the target of an important recreational fishery along the U.S. east coast that is currently the subject of a management controversy regarding allocation and stock structure. Further, the current and probable future distributions of this migratory species are unclear, further complicating decision-making. The objectives of this study are to better define the contemporary distribution of cobia along the U.S. east coast and to project potential shifts …
Sublethal Effects Of Salinity And Temperature On Non-Native Blue Catfish: Implications For Establishment In Atlantic Slope Drainages, Vaskar Nepal, Mary C. Fabrizio
Sublethal Effects Of Salinity And Temperature On Non-Native Blue Catfish: Implications For Establishment In Atlantic Slope Drainages, Vaskar Nepal, Mary C. Fabrizio
VIMS Articles
The distribution and further range expansion of non-native blue catfish Ictalurus furcatus in coastal waters throughout the United States Atlantic slope depend, in part, on the salinity tolerance of the fish. However, temperature-mediated sublethal effects of increased salinities on blue catfish biology are not yet known. We assessed the effects of salinity and temperature on growth, body condition, body composition and food consumption of juvenile blue catfish in a controlled laboratory experiment. Temperature and salinity had an interactive effect on blue catfish biology, although most fish survived 112 days in salinities up to 10 psu. At salinities 9 psu) likely …
Ecosystem Services Of Restored Oyster Reefs In A Chesapeake Bay Tributary: Abundance And Foraging Of Estuarine Fishes, Bruce Pfirrmann, Rochelle D. Seitz
Ecosystem Services Of Restored Oyster Reefs In A Chesapeake Bay Tributary: Abundance And Foraging Of Estuarine Fishes, Bruce Pfirrmann, Rochelle D. Seitz
VIMS Articles
Restoration of oyster reefs in coastal ecosystems may enhance fish and fisheries by providing valuable refuge and foraging habitat, but understanding the effects of restoration requires an improved understanding of fish habitat use and trophic dynamics, coupled with long-term (>5 yr) monitoring of restored habitats. We evaluated the relationship between large (3-5 ha) restored subtidal oyster reefs and mobile estuarine fishes in the Lynnhaven River System (LRS), Virginia, more than 8 yr following reef construction. We compared the (1) diversity, (2) abundance, (3) size, (4) stomach fullness, (5) diet composition, and (6) daily consumption rate of fishes collected from …
Examining Derelict Pot Impacts On Harvest In A Commercial Blue Crab Callinectes Sapidus Fishery, James A. Delbene, Donna M. Bilkovic, Andrew M. Scheld
Examining Derelict Pot Impacts On Harvest In A Commercial Blue Crab Callinectes Sapidus Fishery, James A. Delbene, Donna M. Bilkovic, Andrew M. Scheld
VIMS Articles
Pot fisheries occur worldwide with a significant proportion of the gear becoming derelict. Derelict pots induce detrimental ecological and economic impacts, and more recently were found to reduce blue crab harvests in the Chesapeake Bay commercial fishery. We simulated the presence of derelict pots near actively fished pots in seasonal field experiments to quantify the effect derelict pots have on blue crab harvest. Derelict pots reduced harvests by 30% during the summer, but not during the fall. Female blue crab capture rates were consistently lower when derelict pots were present; while capture rates of the less abundant males were not …
Likely Locations Of Sea Turtle Stranding Mortality Using Experimentally- Calibrated, Time And Space-Specific Drift Models, Bianca S. Santos, Marjorie A.M. Friedrichs, Sarah A. Rose, Susan G. Barco, David M. Kaplan
Likely Locations Of Sea Turtle Stranding Mortality Using Experimentally- Calibrated, Time And Space-Specific Drift Models, Bianca S. Santos, Marjorie A.M. Friedrichs, Sarah A. Rose, Susan G. Barco, David M. Kaplan
VIMS Articles
Sea turtle stranding events provide an opportunity to study drivers of mortality, but causes of strandings are poorly understood. A general sea turtle carcass oceanographic drift model was developed to estimate likely mortality locations from coastal sea turtle stranding records. Key model advancements include realistic direct wind forcing on carcasses, temperature driven carcass decomposition and the development of mortality location predictions for individual strandings. We applied this model to 2009–2014 stranding events within the Chesapeake Bay, Virginia. Predicted origin of vessel strike strandings were compared to commercial vessel data, and potential hazardous turtle-vessel interactions were identified in the southeastern Bay …
Spatiotemporal Trends And Drivers Of Fish Condition In Chesapeake Bay, Robert J. Latour, James Gartland, Christopher F. Bonzek
Spatiotemporal Trends And Drivers Of Fish Condition In Chesapeake Bay, Robert J. Latour, James Gartland, Christopher F. Bonzek
VIMS Articles
Measures of condition in fishes are often used to assess the general well-being of fish populations since condition reflects the biotic and abiotic factors experienced by individuals over moderate time scales. Fish condition can also be used as an indicator of ecosystem suitability in the context of ecosystem-based management. From an ecosystem perspective, evaluation of fish condition is best described over multiple spatiotemporal scales and in a multi-species context. This study analyzed 14 yr (2002-2015) of fisheries-independent trawl survey data to evaluate trends in condition for 16 demersal fishes inhabiting Chesapeake Bay, the largest estuary in the USA. Seasonal and …
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, …
Oyster Reefs As Fish Habitat: Opportunistic Use Of Restored Reefs By Transient Fishes, Juliana M. Harding, Roger L. Mann
Oyster Reefs As Fish Habitat: Opportunistic Use Of Restored Reefs By Transient Fishes, Juliana M. Harding, Roger L. Mann
VIMS Articles
Under the Magnuson-Stevenson Fisheries Management Act of 1996, current fisheries management practice is focused on the conce_pt of Essential Fish Habitat (EFH). Application of the EFH concept to estuarine habitats relates directly to ongoing oyster reef restorat10n efforts. Oyster reef restoration typically creates complex habitat in regions where such habitat is limited or absent. While healthy oyster reefs provide structurally and ecologically complex habitat for many other species from all trophic levels including recreationally and commercially valuable transient finfishes, additional data is required to evaluate oyster reef habitats in the context of essential fish habitat. Patterns of transient fish species …
Do Striped Bass And Blue Crab Abundances Correlate In Chesapeake Bay?, Thomas C. Mosca Iii, Paul J. Rudershausen, Rom Lipcius
Do Striped Bass And Blue Crab Abundances Correlate In Chesapeake Bay?, Thomas C. Mosca Iii, Paul J. Rudershausen, Rom Lipcius
VIMS Articles
We examined a corollary to the hypothesis that striped bass regulate the blue crab population in Chesapeake Bay by preying on juveniles, an expected inverse correlation between striped bass and blue crab abundance. Abundance indices based on Virginia striped bass young-of-the-year beach seine data (1980-1992) were constructed for fish ages 1 - 8, and for the Virginia resident stock component, ages 1 - 5. Fishery-independent, pound net data for fall and spring were also used to construct indices of striped bass abundance in Rappahannock River (1986-1993). Juvenile blue crab abundance indices were constructed based on trawl survey data from the …
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). …