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Full-Text Articles in Aquaculture and Fisheries
Climate Drives Long-Term Change In Antarctic Silverfish Along The Western Antarctic Peninsula, Andrew D. Corso, Deborah K. Steinberg, Sharon E. Stammerjohn, Eric J. Hilton
Climate Drives Long-Term Change In Antarctic Silverfish Along The Western Antarctic Peninsula, Andrew D. Corso, Deborah K. Steinberg, Sharon E. Stammerjohn, Eric J. Hilton
VIMS Articles
Over the last half of the 20th century, the western Antarctic Peninsula has been one of the most rapidly warming regions on Earth, leading to substantial reductions in regional sea ice coverage. These changes are modulated by atmospheric forcing, including the Amundsen Sea Low (ASL) pressure system. We utilized a novel 25-year (1993–2017) time series to model the effects of environmental variability on larvae of a keystone species, the Antarctic Silverfish (Pleuragramma antarctica). Antarctic Silverfish use sea ice as spawning habitat and are important prey for penguins and other predators. We show that warmer sea surface temperature and …
Saved By The Shell: Oyster Reefs Can Shield Juvenile Blue Crabs Callinectes Sapidus, Katherine S. Longmire, Rochelle D. Seitz, Alison Smith, Romuald N. Lipcius
Saved By The Shell: Oyster Reefs Can Shield Juvenile Blue Crabs Callinectes Sapidus, Katherine S. Longmire, Rochelle D. Seitz, Alison Smith, Romuald N. Lipcius
VIMS Articles
Juvenile blue crabs Callinectes sapidus use seagrass and other structured habitats as refuges from predation. Oyster reef habitats provide structural complexity that may offer refuge, but the value of these habitats for juvenile blue crabs has not been examined. We quantified survival of juvenile C. sapidus in structured oyster reef habitat versus unstructured soft-bottom habitat. In a field tethering experiment in the York River, lower Chesapeake Bay (USA), juvenile C.sapidus (10−50 mm carapace width [CW]) were tethered in sand (n = 40) or oyster reef (n = 39)habitats at subtidal sites 1−2 m deep. An underwater camera system was used …
Effect Of Environmental History On The Physiology And Acute Stress Response Of The Eastern Oyster Crassostrea Virginica, Jill Ashey, Emily B. Rivest
Effect Of Environmental History On The Physiology And Acute Stress Response Of The Eastern Oyster Crassostrea Virginica, Jill Ashey, Emily B. Rivest
VIMS Articles
Environmental history (regimes of water quality to which an organism has been exposed in the past) may influence how the physiology of eastern oysters Crassostrea virginica responds to future environmental conditions caused by climate change. Previous research has examined environmental history in a 1-dimensional framework, failing to capture environmental history complexity through space and time. In this study, we examined environmental history as a multi-faceted parameter, incorporating abiotic water quality components, such as temperature, pH, and salinity, that differ among locations. We also assessed how different lengths of environmental histories, defined as proximal and distal, affected oyster physiology and stress …
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 …
Estimating Shifts In Phenology And Habitat Use Of Cobia In Chesapeake Bay Under Climate Change, Daniel P. Crear, Brian E. Watkins, Marjorie A.M. Friedrichs, Pierre St-Laurent, Kevin C. Weng
Estimating Shifts In Phenology And Habitat Use Of Cobia In Chesapeake Bay Under Climate Change, Daniel P. Crear, Brian E. Watkins, Marjorie A.M. Friedrichs, Pierre St-Laurent, Kevin C. Weng
VIMS Articles
Cobia (Rachycentron canadum) is a large coastal pelagic fish species that represents an important fishery in many coastal Atlantic states of the U.S. They are heavily fished in Virginia when they migrate into Chesapeake Bay during the summer to spawn and feed. These coastal habitats have been subjected to warming and increased hypoxia which in turn could impact the timing of migration and the habitat suitability of Chesapeake Bay. With conditions expected to worsen, we project current and future habitat suitability of Chesapeake Bay for cobia and predict changes in their arrival and departure times as conditions shift. To do …
Alternative Substrates Used For Oyster Reef Restoration: A Review, Taylor Goelz, Bruce Vogt, Troy W. Hartley
Alternative Substrates Used For Oyster Reef Restoration: A Review, Taylor Goelz, Bruce Vogt, Troy W. Hartley
VIMS Articles
Oyster populations and reef habitats have notably declined in the last century around the world. The ecological, economic, and cultural values of oysters have led to a variety of restoration efforts seeking to recover these lost benefits. Limitations of the native oyster shell substrate and the large-scale nature of many restoration projects have resulted in the increased use of a variety of alternative, or artificial, substrates to create reef structures. A text mining package was used to conduct a review of alternative substrates used for oyster restoration. Specifically, the review (1) assessed commonly used alternative substrates, (2) locations where alternative …
Restoring The Eastern Oyster: How Much Progress Has Been Made In 53 Years?, Ab Hernandez, Rochelle Brumbaugh, P Fredrick, R Grizzle, Mark Luckenbach, Ch Peterson, C Angelini
Restoring The Eastern Oyster: How Much Progress Has Been Made In 53 Years?, Ab Hernandez, Rochelle Brumbaugh, P Fredrick, R Grizzle, Mark Luckenbach, Ch Peterson, C Angelini
VIMS Articles
Coastal ecosystem restoration is accelerating globally as a means of enhancing shoreline protection, carbon storage, water quality, fisheries, and biodiversity. Among the most substantial of these efforts have been those focused on re-establishing oyster reefs across the US Atlantic and Gulf coasts. Despite considerable investment, it is unclear how the scale of and approaches toward oyster restoration have evolved. A synthesis of 1768 projects undertaken since 1964 reveals that oyster substrate restoration efforts have primarily been concentrated in the Chesapeake Bay and the Gulf Coast, have been heavily reliant on oyster shell, and have re-established 4.5% of the reef area …
Human Influence At The Coast: Upland And Shoreline Stressors Affect Coastal Macrofauna And Are Mediated By Salinity, Rochelle D. Seitz, Kathleen E. Knick, Theresa M. Davenport, Gabrielle G. Saluta
Human Influence At The Coast: Upland And Shoreline Stressors Affect Coastal Macrofauna And Are Mediated By Salinity, Rochelle D. Seitz, Kathleen E. Knick, Theresa M. Davenport, Gabrielle G. Saluta
VIMS Articles
Anthropogenic stressors can affect subtidal communities within the land-water interface. Increasing anthropogenic activities, including upland and shoreline development, threaten ecologically important species in these habitats. In this study, we examined the consequences of anthropogenic stressors on benthic macrofaunal communities in 14 subestuaries of Chesapeake Bay. We investigated how subestuary upland use (forested, agricultural, developed land) and shoreline development (riprap and bulkhead compared to marsh and beach) affected density, biomass, and diversity of benthic infauna. Upland and shoreline development were parameters included in the most plausible models among a candidate set compared using corrected Akaike's Information Criterion. For benthic macrofauna, density …
Spatial Dynamics And Value Of A Marine Protected Area And Corridor For The Blue Crab Spawning Stock In Chesapeake Bay, Rom Lipcius, Wt Stockhausen, Rochelle D. Seitz, Pj Geer
Spatial Dynamics And Value Of A Marine Protected Area And Corridor For The Blue Crab Spawning Stock In Chesapeake Bay, Rom Lipcius, Wt Stockhausen, Rochelle D. Seitz, Pj Geer
VIMS Articles
In lower Chesapeake Bay, a 172,235 ha marine protected area and corridor (MPAC) was recently established to protect blue crab adult females either en route to or at the spawning grounds during the reproductive period. The MPAC was justified due to a recent substantial decline in spawning stock biomass. It was situated in waters deeper than 10 in throughout the lower bay due to the high abundances of adult females in this zone, and it was an expansion of a historical spawning sanctuary near the bay mouth to include northward extensions (upper and lower MPACs). We examined spatial dynamics of …
Potential Bottom-Up Control Of Blue Crab Distribution At Various Spatial Scales, Rochelle D. Seitz, R. Lipcius, Wt Stockhausen, Et Al
Potential Bottom-Up Control Of Blue Crab Distribution At Various Spatial Scales, Rochelle D. Seitz, R. Lipcius, Wt Stockhausen, Et Al
VIMS Articles
Top-down (i.e., predation), bottom-up (i.e., food availability), and physical factors may influence blue crab (Callinectes sapidus) distribution. To assess the role of bottom-up and physical process in blue crab distributions, we concurrently measured density of the blue crab (Callinectes sapidus), density of its principal prey, the Baltic clam (Macoma balthica), and physical characteristics in mud and sand habitats spanning various spatial scales (1-10 km and 10-50 km) in the York River, Chesapeake Bay. Clam and crab densities were intermediate in mud, low in downriver sand, and high in upriver sand. Clam and crab densities were not correlated in mud. whereas …
Utilization Of Marsh And Seagrass Habitats By Early Stages Of Callinectes-Aapidus - A Latitudinal Perspective, R J. Orth, J Van Montfrans
Utilization Of Marsh And Seagrass Habitats By Early Stages Of Callinectes-Aapidus - A Latitudinal Perspective, R J. Orth, J Van Montfrans
VIMS Articles
Seagrass beds and marshes have been identified as important nurseries for the blue crab, Callinectes sapidus. This nursery paradigm is based on blue crab abundance data from trawl, seine and drop-net sampling that has revealed greater abundances in these habitats than in adjacent unvegetated areas. Recently, more quantitative and intensive sampling in seagrass beds and marshes over broad latitudinal scales, combined with manipulative experiments, indicate that the same habitat may vary in utilization on regional scales. Mechanisms accounting for enhanced abundances in these nursery habitats have not been elucidated from a latitudinal perspective. Regional comparisons of blue crab catch data …
Molting In The Mature Female Blue-Crab, Callinectes-Sapidus Rathbun, Kirk J. Havens, Jr Mcconaugha
Molting In The Mature Female Blue-Crab, Callinectes-Sapidus Rathbun, Kirk J. Havens, Jr Mcconaugha
VIMS Articles
The present study examined the hypothesis that mature female blue crabs, Callinectes sapidus, do not enter a terminal anecdysis. Induced molting via eyestalk ablation, size frequency distributions, gonad development and limb regeneration indices from field collected animals are used as indicators of potential post maturity molts. Eyestalk ablation of 15mature females resulted in ecdysis in II individuals approximately 51 days (standard error = 0.64) after ablation, indicating a physiological ability of mature females to complete ecdysis. Analysis of size frequency distributions from catch data indicated two distinct shifts from smaller to larger females, one in early spring and a second …
Variation In Planktonic Availability And Settlement Of Blue-Crab Megalopae In The York River, Virginia, Ej Olmi, J Van Montfrans, Rn Lipcius, R J. Orth, Pw Sadler
Variation In Planktonic Availability And Settlement Of Blue-Crab Megalopae In The York River, Virginia, Ej Olmi, J Van Montfrans, Rn Lipcius, R J. Orth, Pw Sadler
VIMS Articles
Blue crab, Callinectes sapidus, megalopae and juveniles were sampled in the plankton and on natural (grassbeds) and artificial settlement substrates (collectors) at two sites in each of two areas of a lower Chesapeake Bay tributary (York River, Virginia) to examine spatial variability in blue crab recruitment. Spatial patterns of abundance were not consistent across habitats (plankton, artificial collectors and grassbeds) or time. Densities of planktonic megalopae were homogeneous at 1-2 m (within site) but varied at spatial scales of hundreds of meters (between sites) and kilometers (between areas). Settled megalopae were distributed unevenly within and between sites, but their abundance …
Respiration, Electron-Transport Enzymes, And Krebs-Cycle Enzymes In Early Developmental Stages Of The Oyster Crassostrea Virginica, Robert E. Black
Respiration, Electron-Transport Enzymes, And Krebs-Cycle Enzymes In Early Developmental Stages Of The Oyster Crassostrea Virginica, Robert E. Black
VIMS Articles
A marked increase in the rate of respiration during early development has been noted in many different organisms (see Brachet, 1950 ; Boell, 1955). In most cases the changes in respiratory enzymes which might contribute to the respiratory increases have not been fully studied. Of particular interest in this connection are studies which have dealt with enzymes of the tricarboxylic acid (citric acid) cycle, as well as those investigations of the enzymes involved in the transfer of electrons between substrates and oxygen, via the systems which oxidize reduced pyridine nucleotides and succinic acid.
The Concentrations Of Some Enzymes Of The Citric Acid Cycle And Electron Transport System In The Large Granule Graction Of Eggs And Trochophores Of The Oyster, Crassostrea Virginica, Robert E. Black
VIMS Articles
In an accompanying report Black (1962) has shown that considerable changes in the relative activities of several enzymes of the tricarboxylic acid cycle occur during early development of the oyster. Thus, between the blastula and trochophore stages two enzymes, TPN-specific isocitric dehydrogenase and aipha-keto glutaric dehydrogenase, increase 2- to 3-fold, roughly paralleling the increase in respiration during this same period. Five other enzymes were found not to change appreciably during development to the trochophore. These were: aconitase, succinic dehydrogenase, malic dehydrogenase, DPNH oxidase, and cytochrome oxi dase. Following the trochophore stage cytochrome oxidase decreased somewhat in activity, while the other …