Life Sciences Commons^™

Evaluation Of Striped Bass Stocks In Virginia, Monitoring And Tagging Studies, 1999-2003 Annual Report, 1 September 1999 - 31 October 2000, Philip W. Sadler, Robert E. Harris, John E. Olney, Robert J. Latour

Reports

To document continued compliance with Federal law, the Anadromous Fishes Program of the Virginia Institute of Marine Science (VIMS) has monitored the size and age composition, sex ratio and maturity schedules of the spawning striped bass stock in the Rappahannock River since December 1981 utilizing commercial pound nets and, since 1991, variable-mesh experimental gill nets. Spawning stock assessment was expanded to include the James River in 1994 utilizing 11 commercial fyke nets and variable-mesh experimental gill nets. The use of fyke nets was discontinued after 1997. In conjunction with the monitoring studies, tagging programs have been conducted in the James …

Coherence Of Internal Tide Modulations Along The Hawaiian Ridge, Gary T. Mitchum, Stephen M. Chiswell

Marine Science Faculty Publications

Long time series of sea level from tide gauges along the north side of the Hawaiian Ridge and shorter series of dynamic heights inferred from inverted echo sounders moored just north of the main Hawaiian Islands are examined for evidence of internal tides at the M₂ frequency. We find that the amplitudes and phases of the M₂ tidal components have low-frequency variability, which is consistent with a superposition of an internal tide with the larger barotropic tide. Further, the low-frequency variability is correlated with low-frequency changes in the depth of the pycnocline, which suggests a simple physical mechanism …

Temperature Effects On Export Production In The Open Ocean, Ea Laws, Pg Falkowki, Walker O. Smith Jr., H Ducklow, Jj Mccarthy

VIMS Articles

A pelagic food web model was formulated with the goal of developing a quantitative understanding of the relationship between total production, export production, and environmental variables in marine ecosystems. The model assumes that primary production is partitioned through both large and small phytoplankton and that the food web adjusts to changes in the rate of allochthonous nutrient inputs in a way that maximizes stability, i.e., the ability of the system to return to steady state following a perturbation. The results of the modeling exercise indicate that ef ratios, defined as new production/total production = export production/total production, are relatively insensitive …

Effects Of Nutrient Enrichment On Growth And Phlorotannin Production In Fucus Gardneri Embryos, Kathryn L. Van Alstyne Dr., Karen N. Pelletreau

Shannon Point Marine Center Faculty Publications

Resource-allocation models predict trade-offs between growth and chemical defense. The carbon/nutrient balance hypothesis (CNBH) predicts that plants will allocate carbon to growth when nutrients are abundant and allocate it to carbon-based antiherbivore defenses when nutrients are limiting. In marine systems, field and laboratory tests of the CNBH with phlorotannin-producing algae have generally supported the predictions of the model. However, these tests have all measured phlorotannin concentrations in adult algae rather than juveniles, which are susceptible to higher

Modifications Of The C37 Alkenone And Alkenoate Composition In The Water Column And Sediment: Possible Implications For Sea Surface Temperature Estimates In Paleoceanography, Joan O. Grimalt, Jürgen Rullkötter, Marie-Alexandrine Sicre, Roger Summons, John Farrington, H. Rodger Harvey, Miguel Goñi, Ken Sawada

OES Faculty Publications

The literature pertaining to C37 alkenone and C37 and C38 alkenoate production and diagenesis has been reviewed and evaluated for issues that might jeopardize their usefulness in paleotemperature estimation. We also examined the use of the C37 alkenones as paleoproductivity indicators, the stability of their δ13C isotopic compositions, and their incorporation into the nonsolvent extractable organic matter fraction. Biological transformation of organic matter by bacteria and zooplankton does not appear to cause significant changes to the ratio of C37:2 and C37:3 alkenones, but there are major alterations in the relative composition of alkenoates. Studies of water column processes and postdepositional …

Andros Island Flora And Fauna In The New Millennium, Jose V. Lopez, Cheryl L. Peterson, Felix Morales, Luther Brown

Marine & Environmental Sciences Faculty Articles

No abstract provided.

Phytosociological Analysis Of Restored And Managed Grassland Habitat Within An Urban National Park, Andrew M. Greller, Celestine Durando, Leslie F. Marcus, D. Siril A. Wijesundara, Michael D. Byer, Robert Cook, John T. Tanacredi Ph.D.

Faculty Works: CERCOM

Floyd Bennett Field (FBF), 579 ha in extent, is a division of Gateway National Recreation Area. It is the site of a former airfield, constructed by filling salt marshes with dredged materials. Except for the portion known locally as the “North Forty,” all sections of FBF have been cut over to maintain low vegetation. A grassland management plan (GRAMP) for 165 ha was initiated in 1986, to maintain habitats for open-country birds. Over the next few years, encroaching woody vegetation was removed manually and mechanically from the management area. Since then, it has been maintained as a grassland and receives …

Orbitally Induced Climate And Geochemical Variability Across The Oligocene/Miocene Boundary, Hilary A. Paul, James C. Zachos, Benjamin P. Flower, Aradhna Tripati

Marine Science Faculty Publications

To assess the influence of orbital-scale variations on late Oligocene to early Miocene climate and ocean chemistry, high-resolution (similar to 5 kyr) benthic foraminiferal carbon and oxygen isotope and percent coarse fraction time series were constructed for Ocean Drilling Program site 929 on Ceara Rise in the western equatorial Atlantic. These time series exhibit pervasive low- to high-frequency variability across a 5-Myr interval (20.5-25.4 Ma). The records also reveal several large-scale secular variations including two positive (similar to 1.6 parts per thousand) oxygen isotope excursions at 22.95 and 21.1 Ma, suggestive of large but brief glacial maxima (Mi-l and Mi-la …

Seasonal Variations Of Size-Fractionated Phytoplankton Along The Salinity Gradient In The York River Estuary, Virginia (Usa), Y Sin, Rl Wetzel, I. C. Anderson

VIMS Articles

The dynamics of phytoplankton size structure were investigated in the freshwater, transitional and estuarine zones of the York River over an annual cycle. The contribution of large cells (microplankton, >20 mu m) to total concentrations of chlorophyll a increased downstream during winter, whereas that of small cells (nanoplankton, 3-20 mu m; picoplankton,m) increased downstream during summer. In the freshwater region, the contribution of micro phytoplankton to total concentrations of chlorophyll a was significant during warm seasons (spring and summer) but not during colder seasons (winter), whereas the contribution of small-sized cells (especially picoplankton) increased during cold seasons. Temperature, light and …

Multiple Spatial Scale Assessment Of Coral Reef And Hard-Bottom Community Structure In The Florida Keys National Marine Sanctuary, Steven Miller, Dione W. Swanson, Mark Chiappone

Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

The zoning plan for the Florida Keys National Marine Sanctuary (FKNMS) established 23 relatively small no-fishing zones distributed mostly along the offshore reef tract in 1997. In 1999, a two-stage, stratified random sampling design based on the proportion of coral reef and hard-bottom types within the FKNMS was conducted. Our study focused on differences in coverage, density, and condition of benthic organisms with respect to habitat type, regional variations, and differences between no-fishing zones and reference sites at 80 locations spanning 200 km. Most variables exhibited significant spatial differences by habitat type or between individual no-fishing zones and reference sites …

Changes In Bacterioplankton Metabolic Capabilities Along A Salinity Gradient In The York River Estuary, Virginia, Usa, G. E. Schultz, H. W. Ducklow

VIMS Articles

Changes in metabolic capabilities of bacterial communities along the estuarine salinity gradient may affect the extent of organic matter processing and bacterial growth and accumulation during transit through the system; As part of a larger study of estuarine microbial processes, we attempted to quantify differences in bacterial community structure using Biolog plates. Biolog GN plates (Biolog, Inc., Hayward, CA, USA) were used to determine differences in bacterioplankton community metabolic potential. Biolog GN microplates are 96-well microtiter plates in which each well contains an individual carbon source as well the redox dye tetrazolium violet. As bacteria grow and oxidize each substrate, …

Evaluating The Recruitment Of American Eel, Anguilla Rostrata, To The Potomac - Spring 2000 : March 2000 - June 2000, Patrick J. Geer, Julie A. Weeder, Steven Hammond, Rudolph Lukacovic

Reports

Measures of juvenile recruitment success have long been recognized as a valuable fisheries management tool. In the Chesapeake Bay, these measures have provided reliable indicators for future year class strength for blue crabs (Lipcius and van Engel, 1990), striped bass (Goodyear, 1985), and several other recreationally important fishes (Geer and Austin, 1999).

The American eel, Anguilla rostrata, is a valuable commercial species along the entire Atlantic coast from New Brunswick to Florida. Landings along the U.S. Atlantic coast have varied from 290 MT in 1962 to a high of 1600 MT in 1975 (NMFS, 1999). In recent years there seems …

Environmental Survey Of Potential Sand Resource Sites, Offshore Delaware And Maryland : Final Report, Virginia Institute Of Marine Science

Reports

• Technical summary / Carl H. Hobbs
• Non-technical summary / Carl H. Hobbs
• Part. 1. Benthic mapping and resource evaluation of potential sand mining areas, offshore Mayland and Delaware, 1998-1999 / G.R. Cutter and R.J. Diaz
• Part. 2. Transitory species (vertebrate nekton) / John A. Musick
• Part. 3. Literature survey of reproductive finfish and ichthyoplankton present in proposed sand mining locations within the Middle Atlantic Bight / John Olney, Donna Marie Bilkovic
• Part. 4. Potential modifications to waves due to dredging and other oceanographic considerations / Jerome P.-Y. Maa, Sung C. Kim
• Part. 5. Maryland-Delaware shoreline : long-term trends and short-term …

North Atlantic Intermediate To Deep Water Circulation And Chemical Stratification During The Past 1 Myr, Benjamin P. Flower, D. W. Oppo, J. F. Mcmanus, K. A. Venz, D. A. Hodell, J. L. Cullen

Marine Science Faculty Publications

Benthic foraminiferal carbon isotope records from a suite of drill sites in the North Atlantic are used to trace variations in the relative strengths of Lower North Atlantic Deep Water (LNADW), Upper North Atlantic Deep Water (UNADW), and Southern Ocean Water (SOW) over the past 1 Myr. During glacial intervals, significant increases in intermediate-to-deep delta(13)C gradients (commonly reaching >1.2 parts per thousand) are consistent with changes in deep water circulation and associated chemical stratification. Bathymetric delta(13)C gradients covary with benthic foraminiferal delta(18)O and covary inversely with Vostok CO2, in agreement with chemical stratification as a driver of atmospheric CO2 changes. …

The Influence Of The Pressure Head On The Indonesian Seas Circulation, William H. Burnett, Vladimir M. Kamenkovich, George L. Mellor, Arnold L. Gordon

Faculty Publications

A high resolution, regional, non-linear, barotropic ocean model (2D POM) was used to show that a pressure difference between the Pacific and Indian Ocean does not significantly influence the total transport of the Indonesian throughflow.

Burrow Morphology And Behavior Of The Mud Shrimp Upogebia Omissa (Decapoda: Thalassinidea: Upogebiidae), Vania Rodrigues Coelho, Roland Arthur Cooper, Sergio De Almeida Rodrigues

Collected Faculty and Staff Scholarship

The burrow morphology, burrowing behavior and feeding mechanisms of the thalassinidean shrimp Upogebia omissa were studied. Twenty burrow casts were made in situ with epoxy resin, and an overall 'Y' shape was most frequently observed. Several burrows consisted of a single, oblique tunnel; burrow diameter was positively correlated with burrow length, maximum depth and distance between openings. Additionally, burrow length was positively associated with maximum depth, indicating that as burrow length increased burrow depth increased; i.e. burrows spread vertically rather than horizontally. Total sediment displacement by the burrows accounted for 2.6 % of sediment to a depth of 30 cm. …

Monitoring Relative Abundance Of American Shad In Virginia's Rivers Annual Report 1999, John E. Olney Sr., John M. Hoenig

Reports

A moratorium on the taking of American shad (Alosa sapidissima) in the Chesapeake Bay and its tributaries was established by the Virginia Marine Resources Commission (VMRC) beginning 1 January 1994. The prohibition applied to both recreational and commercial fishers. The moratorium was imposed at a time when commercial catch rates of American shad in Virginia's rivers were experiencing declines. Data from the commercial fishery were the best available for assessing the status of individual stocks. Catch-per-unit-effort (CPUE) data were compiled from logbooks that recorded landings by commercial fishermen using staked gill nets at various locations throughout the middle reaches of …

Local Demographics Of The Polychaete Chaetopterus Pergamentaceus Within The Lower Chesapeake Bay And Relationships To Environmental Gradients, Ml Thompson, Linda C. Schaffner

VIMS Articles

Chaetopterus pergamentaceus is an abundant and functionally important species within the soft sediment, subtidal benthic community of lower Chesapeake Bay. The present study elucidates spatial relationships in density, individual ash-free dry weight, total station ash-free dry weight and growth rates for juveniles and adults from 2 yrs of sampling (1994, 1995) at 12 stations in the lower Chesapeake Bay. A strong inverse relationship (r(2) = 0.69) was observed between growth rates and total density for juveniles when data from a low(1994) and high(1995) recruitment year were considered. Common parameters among stations characterized by high density/low growth were: (1) depth (maximum …

Bacterial Consumption Of Doc During Transport Through A Temperate Estuary, Pa Raymond, Je Bauer

VIMS Articles

Bacterial utilization of natural levels of dissolved organic carbon (DOC) was measured in the York River estuary, a sub-estuary of the Chesapeake Bay. This study was undertaken in order to elucidate spatial and temporal changes in bacterial carbon utilization and to evaluate its importance as a pathway for organic matter transformation in estuaries. Multiple pools of DOC were defined based on decomposition kinetics. The first pool (G(1)) made up a mean of 2.8% of total DOC and had turnover times of less than or equal to 5 d. The second pool (G(2)) comprised an average of 4.9% of total DOC …

The Crest, Summer 2000, Virginia Institute Of Marine Science

Reports

Table of Contents:

• VIMS Scientists Successfully Spawn Cobia
• NMFS Faculty Position Established at VIMS
• Scientists Discover New Species of Perkinsus
• Researchers Discover New Pollutants Infiltrating Virginia Rivers
• Sea Scallop Research Resumed in June
• MARSH Project Will Help Save Tidal Wetlands
• Virginia's Changing Coastal Community - Indicators of Change
• New Pound-Net Design Spares Young Fish
• VIMS Scientist Studies Oysters in India
• American Shad Focus of Unique Study
• From the Coleman Bridge to Menai Bridge:
• VIMS Professor Leads Field-Course in Wales
• New Experimental Design Course for Teachers
• Students Teaching Students
• Horseshoe Crab Research is Timely
• Award Winning Bridge Website Receives Renewed Funding …

Restoration Of Submerged Aquatic Vegetation (Sav) In The Tidal Freshwater James River: Year 2, Ken Moore, Kevin Segerblom, Betty Neikirk, James Fishman

Reports

No abstract provided.

Long-Term Pyrene Exposure Of Grass Shrimp, Palaemonetes Pugio, Affects Molting And Reproduction Of Exposed Males And Offspring Of Exposed Females, Eva Oberdörster, Marius Brouwer, Thea Hoexum-Brouwer, Steve Manning, John A. Mclachlan

Faculty Publications

The objective of this study was to investigate the impact of long-term pyrene exposure on molting and reproduction in the model estuarine invertebrate, the grass shrimp (Palaemonetes pugio). Grass shrimp were exposed to measured concentrations of 5.1, 15.0, and 63.4 ppb (mu g/L) pyrene for 6 weeks, during which time we determined molting and survivorship. At the end of the exposure, we immediately sacrificed some of the shrimp for biomarker (CYP1A and vitellin) analyses. The remaining shrimp were used to analyze fecundity and embryo survivorship during an additional 6 weeks after termination of pyrene exposure. Male shrimp at the highest …

Near-Surface Phytoplankton Distribution In The Western Intra-Americas Sea: The Influence Of El Niño And Weather Events, Nelson M. Gonzalez, Frank E. Muller-Karger, Sergio Cerdeira Estrada, Roberto Perez De Los Reyes, Ivan Victora Del Rio, Pedro Cardenas Perez, Ida Mitrani Arenal

Marine Science Faculty Publications

The space-rime variation of phytoplankton pigments in the western Intra-Americas Sea (IAS), in the vicinity of the island of Cuba, is examined using digital images obtained with the Coastal Zone Color Scanner sensor flown aboard the Nimbus 7 satellite from 1978 to 1986. The results are compared to historical in situ hydrographic observations. A marked seasonality in pigment concentration was observed in waters around Cuba, with an average of 0.07 mg m(-3) in summer (April-September) and 0.13 mg m-3 during winter (October-March). The range of variation in pigment concentration was larger in the Gulf of Mexico relative to the western …

Form Ia Rbcl Transcripts Associated With A Low Salinity/High Chlorophyll Plume ('Green River') In The Eastern Gulf Of Mexico, John H. Paul, Albin Alfreider, Jordan B. Kang, Roger A. Stokes, Dale Griffin, Lisa Campbell, Erla Ornolfsdottir

Marine Science Faculty Publications

Coastal plumes of low salinity water that extend hundreds of kilometers offshore into oligotrophic waters are often found in the Gulf of Mexico. To characterize one such feature, a series of photoautotrophic activity and biomass parameters were measured at 2 stations in the eastern Gulf of Mexico, including pigments by high performance liquid chromatography (HPLC), autotrophic picoplankton abundance by flow cytometry, photoautotrophic ¹⁴C-HCO₃^- fixation, and Ribulose-1,5-diphosphate carboxylase large subunit gene (rbcL) transcriptional activity. One sampling site (Stn 4) was in a 15 m deep, low salinity (29.8 ppt) plume 242 km west of Tampa Bay. …

Zoosporulation Of A New Perkinsus Species Isolated From The Gills Of The Softshell Clam Mya Arenaria, Sm Mclaughlin, Bd Tall, A Shaheen, Ee Elsayed, M Faisal

VIMS Articles

A gill-associated Perkinsus sp. isolated from the softshell clam (Myo arenaria) is described as a new species, P. chesapeaki sp. nov. Examination of the parasite in seawater cultures revealed life cycle stages and zoosporulation processes similar to those described for other species of the genus Perkinsus. Prezoosporangia developed thickened cell walls upon contraction of the cytoplasm and development of a distinctive clear area between the cell wall and the protoplast. Successive bipartition of the protoplast led to the formation of hundred's of zoospores within mature sporangia. Zoospores were released into seawater through one or more discharge tubes, Ultrastructural studies revealed …

Restoration Of Submerged Aquatic Vegetation (Sav) In The Tidal Freshwater James River: 1999 Pilot Study, Ken Moore, R J. Orth, James Fishman

Reports

No abstract provided.

An Upwelling Case Study On Florida's West Coast, Robert H. Weisberg, Bryan D. Black, Zhenjiang Li

Marine Science Faculty Publications

Using a combination of satellite sea surface temperature imagery; in situ currents, temperature, and sea level data; and a numerical circulation model, we describe an upwelling event observed along Florida's west coast. Although ubiquitous features of continental shelves, descriptions of coastal upwellings (or downwellings) are generally complicated by the continuum of processes in which they occur. For the case study presented the winds were light, and the baroclinic background currents were steady for several days prior to the event. These conditions allow the evolution of a specific wind-driven upwelling event to be viewed as an initial value problem. The data …

Turbidite Megabeds In An Oceanic Rift Valley Recording Jokulhlaups Of Late Pleistocene Glacial Lakes Of The Western United States, G.G. Zuffa, W.R. Normark, F. Serra, Charlotte A. Brunner

Faculty Publications

Escanaba Trough is the southernmost segment of the Gorda Ridge and is filled by sandy turbidites locally exceeding 500 m in thickness. New results from Ocean Drilling Program (ODP) Sites 1037 and 1038 that include accelerator mass spectrometry (AMS) C-14 dates and revised petrographic evaluation of the sediment provenance, combined with high-resolution seismic-reflection profiles, provide a lithostratigraphic framework for the turbidite deposits. Three fining-upward units of sandy turbidites from the upper 365 m at ODP Site 1037 can be correlated with sediment recovered at ODP Site 1038 and Deep Sea Drilling Program (DSDP) Site 35. Six AMS C-14 ages in …

Basinsim 1.0 A Windows-Based Watershed Modeling Package, Ting Dai, Richard L. Wetzel, Tyler R.L. Christensen, E. Amy Lewis

Reports

BasinSim 1.0 for Windows is the product of a NOAA Coastal Zone Management grant (through the Virginia Coastal Resources Management Program) awarded to Drs. Ting Dai, R. L. Wetzel, I. C. Anderson, and L. W. Haas at the Virginia Institute of Marine Science, College of William and Mary in 1998. Additional support has been provided for the development and testing of this package and production of this user’s guide by grants from Virginia’s Chesapeake Bay Local Assistance Department (CBLAD). BasinSim 1.0 is a desktop simulation system that predicts sediment and nutrient loads for small to mid-sized watersheds. The simulation system …

Larval Trophodynamics, Turbulence, And Drift On Georges Bank : A Sensitivity Analysis Of Cod And Haddock, Francisco E. E. Werner, Brian R. Mackenzie, R. Ian Perry, R. Gregory Lough, Christopher E. Naimie, Brian O. Blanton, John A. Quinlan

Dartmouth Scholarship

Using an individual-based model approach we consider trophodynamic effects on the growth and survival of larval cod (Gadus morhua) and haddock (Melanogrammus aeglefinus) on Georges Bank during late winter/early spring. These studies represent an extension of results described in Werner et al. (1996; Deep-Sea Res. II), wherein the effect of turbulence-enhanced larval-prey contact rates increased the effective prey concentration resulting in growth of cod larvae consistent with observed rates in the field. We reformulated the feeding of the larvae to include existing relationships between maximum prey-length and larval-length and we examined: (i) larval search behaviour and …