Marine Biology Commons^™

Spring 1999, Nsu Oceanographic Center

Currents

No abstract provided.

Particle Trajectories In An Indian Ocean Model And Sensitivity To Seasonal Forcing, Meredith A. Haines, Rana A. Fine, Mark E. Luther, Zaihua Ji

Marine Science Faculty Publications

Trajectory experiments in a thermocline layer of an Indian Ocean model are used to investigate the role of different meridional transport mechanisms and quantify spreading pathways and rates under different forcing. Particles are introduced along two boundaries: the south Indian Ocean at 30 degrees S and the Indonesian Throughflow. Particles are advected horizontally within the layer by archived model velocity fields (1/3 degrees X 1/3 degrees resolution) for a period of 50 years. The velocity fields are the result of forcing the model by monthly mean climatology (case A). The distribution of particles within the Tropics suggests efficient ater mass …

Analysis Of Historical Distribution Of Submerged Aquatic Vegetation (Sav) In The James River, Ken Moore, David J. Wilcox, R J. Orth, Eva Bailey

Reports

Analyses of historical photography and ground surveys dating from the 1930s indicate that approximately 1645 hectares of SAV have been historically present in shallow water regions throughout the James River. This compares to 77 hectares of vegetation reported in 1997 and a James River Tier I SAV restoration goal of 107 hectares (areas mappped with SAV from 1971- 1991). Overall, the temporal and spatial patterns of loss of SAV populations in the James River suggest declines occurred first in the tidal freshwater regions of the upper James beginning approximately 50 years ago, and then subsequently in the lower James beginning …

Western Pacific Interannual Variability Associated With The El Niño‐Southern Oscillation, Chunzai Wang, Robert H. Weisberg, Jyotika I. Virmani

Marine Science Faculty Publications

Observations of sea surface temperature (SST), sea level pressure (SLP), surface wind, and outgoing longwave radiation (OLR) show that the El Niño‐Southern Oscillation (ENSO) displays western Pacific anomaly patterns in addition to eastern Pacific anomaly patterns. During the warm phase of ENSO, warm SST and low SLP anomalies in the equatorial eastern Pacific and low OLR anomalies in the equatorial central Pacific are accompanied by cold SST and high SLP anomalies in the off‐equatorial western Pacific and high OLR anomalies in the off‐equatorial far western Pacific. Also, while the zonal wind anomalies over the equatorial central Pacific are westerly, those …

Particle Fluxes During Austral Spring And Summer In The Southern Ross Sea, Antarctica, Vernon L. Asper, Walker O. Smith Jr.

Faculty Publications

The flux of particles from the euphotic zone through 200 m was investigated on the Ross Sea continental shelf during two cruises, the first in November-December 1994 and the second in December 1995 and January 1996. An assessment of surface layer phytoplankton biomass and productivity was made simultaneously. Particle flux was measured using floating sediment traps whose collection efficiency was assessed rigorously. Phytoplankton biomass and productivity increased rapidly in November-December, and biomass was maximal in mid-December. Thereafter productivity appeared to decline substantially. Biomass declined as well, but mot as rapidly as productivity. Vertical flux rates were low early in the …

Semianalytic Moderate-Resolution Imaging Spectrometer Algorithms For Chlorophyll A And Absorption With Bio-Optical Domains Based On Nitrate-Depletion Temperatures, Kendall L. Carder, F. R. Chen, Z. P. Lee, S. K. Hawes, D. Kamykowski

Marine Science Faculty Publications

This paper describes algorithms for retrieval of chlorophyll a concentration and phytoplankton and gelbstoff absorption coefficients for the Moderate-Resolution Imaging Spectrometer (MODIS) or sensors with similar spectral channels. The algorithms are based on a semianalytical, bio-optical model of remote sensing reflectance, R_rs([lambda]). The R_rs([lambda]) model has two free variables, the absorption coefficient due to phytoplankton at 675 nn, a_[Phi](675), and the absorption coefficient due to gelbstoff at 400 nm, a_g(400). The R_rs model has several parameters that are fixed or can be specified based on the region and season of the …

Response Of The West Florida Shelf Circulation To Climatological Wind Stress Forcing, Huijun Yang, Robert H. Weisberg

Marine Science Faculty Publications

The response of the west Florida: continental shelf circulation to monthly mean climatological wind forcing is investigated by using the three-dimensional, primitive equation Princeton Ocean Model. Two basic seasonal patterns of circulation and sea surface elevation occur under a barotropic setting: A winter pattern from October to March and a summer pattern from April to September. An interesting finding in winter is an anticyclonic gyre over the northeastern (Florida Big Bend) region that merges with a northwestward flow from the south. The Big Bend Gyre is caused by a convergence of two separate flows: A nearshore along-shelf southeastward flow and …

Number 38 (March 1999), Southern Fishes Council

Southeastern Fishes Council Proceedings

(March 1999) - Retention of passive integrated transponder (PIT) tags for individual identification of warmwater stream fishes. By Carol E. Johnston and Elizabeth B. Smithson

Laboratory observations of spawning behavior in two species of snubnose darters, Etheostoma colorosum and E. tallapoosae. By Carol E. Johnston, Nathan A. Farnau, Henry L. Bart and Amanda K. Howard

Minutes, Business Meeting, 24th Annual Meeting, Southeastern Fishes Council

Regional Southeastern Fishes Council Reports News Notes

Laboratory Observations Of Spawning Behavior In Two Species Of Snubnose Darters, Etheostoma Colorosum And E. Tallapoosae, Carol E. Johnston, Nathan A. Farnau, Henry L. Bart, Amanda K. Howard

Southeastern Fishes Council Proceedings

No abstract provided.

Front Matter, Southeastern Fishes Council

Southeastern Fishes Council Proceedings

No abstract provided.

Retention Of Passive Integrated Transponder (Pit) Tags For Individual Identification Of Warmwater Stream Fishes, Carol E. Johnston, Elizabeth B. Smithson

Southeastern Fishes Council Proceedings

No abstract provided.

Minutes, Business Meeting, Southeastern Fishes Council

Southeastern Fishes Council Proceedings

No abstract provided.

News And Notes, Southeastern Fishes Council

Southeastern Fishes Council Proceedings

No abstract provided.

Regional Southeastern Fishes Council Reports, Southeastern Fishes Council

Southeastern Fishes Council Proceedings

No abstract provided.

A Method For Estimating Marine Habitat Values Based On Fish Guilds, With Comparisons Between Sites In The Southern California Bight, Alan B. Bond, John S. Stephens, Daniel J. Pondella Ii, James M. Allen, Mark Helvey

Daniel Pondella

Habitat valuation is an essential tool for tracking changes in habitat quality and in adjudicating environmental mitigation. All current methods for estimating habitat values of coastal marine sites rely heavily on the opinion of experts or on data variables that can readily be manipulated to influence the outcome. As a result, unbiased, quantitative comparisons between the values of different marine habitats are generally unavailable. We report here on a robust, objective technique for the valuation of marine habitats that makes use of data that are commonly gathered in surveys of marine fish populations: density, fidelity, and mean size. To insure …

Non-Redfield Carbon And Nitrogen Cycling In The Arctic: Effects Of Ecosystem Structure And Dynamics, Kendra L. Daly, Douglas W.R. Wallace, Walker O. Smith Jr., Annelie Skoog, Ruben Lara, Michel Gosselin, Eva Falck, Patricia L. Yager

VIMS Articles

The C:N ratio is a critical parameter used in both global ocean carbon models and field studies to understand carbon and nutrient cycling as well as to estimate exported carbon from the euphotic zone. The so-called Redfield ratio (C:N = 6.6 by atoms) [Redfield et nl., 1963] is widely used for such calculations. Here we present data from the NE Greenland continental shelf that show that most of the C:N ratios for particulate (autotrophic and heterotrophic) and dissolved pools and rates of transformation among them exceed Redfield proportions from June to August, owing to species composition, size, and biological interactions. …

Orbitally-Tuned Sr Isotope Chemostratigraphy For The Late Middle To Late Miocene, E. E. Martin, N. J. Shackleton, J. C. Zachos, Benjamin P. Flower

Marine Science Faculty Publications

We present a Sr chemostratigraphic reference section for the late middle to late Miocene (14-5 Ma) from Ocean Drilling Program site 926 on the Ceara Rise. This site combines a precise, orbitally tuned timescale with a high sedimentation rate (15 m/m.y.), continuous deposition, and excellent biostratigraphic control. The Sr isotope curve is based on measurements of cleaned, planktonic foraminifera at 100-200 kyr sample intervals and it illustrates periods of rapid change in Sr-87/Sr-86 alternating with periods of little change. Chemostratigraphically-defined ages for these intervals can be determined within +/-0.8 m.y. and +/-1.6 m.y, respectively. There is excellent correlation with the …

Gloucester County Shoreline And Tidal Marsh Inventory, Marcia Berman, Harry Berquist, Sharon Dewing, George Thomas, Rose Laird

Reports

This inventory is intended to serve as a useful planning tool for managers, planners, regulators, and environmentalists with an interest in Gloucester County. This report documents conditions measured in the County of Gloucester using remote sensing techniques. Two separate activities have occurred in tandem to develop this inventory of tidal marsh, and shoreline features. First, a delineation of tidal marshes within the county used high end image processing software along with color infra-red imagery to delineate the boundaries oftidal marshes'within 33 georeferenced scenes. The process calculates the amount of tidal marsh measured within each river segment in acres. Second, the …

Selective Feeding Behavior Of Larval Naked Gobies Gobiosoma Bosc And Blennies Chasmodes Bosquianus And Hypsoblennius Hentzi: Preferences For Bivalve Veligers, Jm Harding

VIMS Articles

Naked gobies Gobiosoma bose, striped blennies Chasmodes bosquianus, and feather blennies Hypsoblennius hentzi provide important intermediate links within the trophic structure of estuarine oyster reef communities. Predator-prey interactions between planktonic larvae of these fishes and larval eastern oysters Crassostrea virginica may influence recruitment success within oyster reef communities. These 3 species of oyster reef fish larvae were cultured from wild nests and used in multifactorial laboratory feeding experiments with larval oysters or hard clams Mercenaria mercenaria as well as wild plankton as prey items to determine the effects of predator age, predator concentration, and prey type on feeding selectivity of …

Modeling The Msx Parasite In Eastern Oyster (Crassostrea Virginica) Populations. Ii. Salinity Effects, Michelle C. Paraso, Susan E. Ford, Eric N. Powell, Eileen E. Hofmann, John M. Klinck

CCPO Publications

An oyster population model coupled with a model for Haplosporidium nelsoni, the causative agent of the oyster disease MSX, was used with salinity time-series constructed from Delaware River flow measurements to study environmentally-induced variations in the annual cycle of this disease in Delaware Bay oyster populations. Model simulations for the lower Bay (high salinity) sire reproduced the annual cycle observed in lower Delaware Bay. Simulations at both upper Bay (low salinity) and lower Bay sites produced prevalences and intensities that were consistent with field observations. At all sites, low freshwater discharge resulted in increased disease levels, whereas high freshwater …

Modeling The Msx Parasite In Eastern Oyster (Crassostrea Virginica) Populations. I. Model Development, Implementation, And Verification, Susan Ford, Eric Powell, John Klinck, Eileen Hofmann

CCPO Publications

A mathematical model simulating the host-parasite-environmental interactions of eastern oysters (Crassostrea virginica) and the pathogen, Haplosporidium nelsoni, which causes MSX disease, has been developed. The model has 2 components. One replicates the infection process within the oyster and the other simulates transmission. The infection-development component relies on basic physiological processes of both host and parasite, modified by the environment, to reproduce the observed annual prevalence cycle of H. nelsoni. Equations describing these rates were constructed using data from long-term field observations, and field and laboratory experiments. In the model, salinity and temperature have direct effects upon …

Modeling The Msx Parasite In Eastern Oyster (Crassostrea Virginica) Populations. Iii. Regional Application And The Problem Of Transmission, Eric N. Powell, John M. Klinck, Susan E. Ford, Eileen E. Hofmann, Stephen J. Jordon

CCPO Publications

A model of transmission for Haplosporidium nelsoni, the disease agent for MSX disease, is developed and applied to sites in Delaware Bay and Chesapeake Bay. The environmental factors that force the oyster population- H. nelsoni model are salinity, temperature, food, and total suspended solids. The simulated development of MSX disease was verified using 3 time series of disease prevalence and intensity: 1960 to 1970 and 1980 to 1990 for Delaware Bay, and 1980 to 1994 for Chesapeake Bay, and for a series of sites covering the salinity gradient in each bay. Additional simulations consider the implications of assumptions made …

1998 Annual Awards, Virginia Institute Of Marine Science

Miscellaneous

The Annual Awards ceremony is an occasion in which new employees and volunteers are introduced, employee service is recognized and student and faculty awards are presented.

The Blind Cave Fish That Never Was, Aldemaro Romero Jr.

Publications and Research

No abstract provided.

Epi-And Mesopelagic Fishes, Acoustic Data, And Sst Images Collected Off Lanzarote, Fuerteventura, And Gran Canaria, Canary Islands, During Cruise "La Bocaina 04-97", F. Bordes, F. Uiblein, R. Castillo, A. Barrera, J. J. Castro, J. Coca, J. Gomez, K. Hansen, V. Hernandez, N. Merrett, M. Miya, T. Moreno, F. Perez, A. Ramos, Tracey Sutton, M. Yamaguchi

Marine & Environmental Sciences Faculty Reports

During cruise "La Bocaina 0497" a series of 14 tows with a commercial pelagic trawl at depths between 20 and 700 m and an acoustic survey with a SIMRAD EK-500 echosounder were carried out in neritic and adjacent oceanic waters off Lanzarote, Fuerteventura, and Gran Canaria, Canary islands. In addition, SST images were obtained to get some informations on the prevailing hydrological conditions in the study area.

Of the 14 trawl tows ten were successful and resulted in capture of a total of 2166 fishes belonging to 81 species, 53 genera and 28 families. Ten species proved to be new …

Sea Turtle Conservation Program, Broward County, Fl 1999 Report, Curtis M. Burney, William E. Margolis

Marine & Environmental Sciences Faculty Reports

No abstract provided.

Skeletal Architecture And Density Banding Analysis Technique For Diploria Strigosa By X-Ray Computed Tomography, Kevin P. Helmle, Richard E. Dodge (Editor)

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

Coral skeletal density information is a useful growth parameter and may be coupled with extension rates to determine calcification rates. The conventional process for density determination is often cumbersome and requires some parameters which are difficult to precisely specify (e.g., Mass absorption coefficients). We have developed a technique and windows based computer program which enables the rapid collection of coral density data. The coral skeleton slab is xradiographed with an aluminum wedge. Thickness and density of the aluminum wedge, thickness of the coral slab, density of pure coral aragonite, and digitized images of the coral and wedge x-radiographs provide necessary …

Winter 1999, Nsu Oceanographic Center

Currents

No abstract provided.

Environmental Stress In Hard Coral: Evaluating Lipid As An Indicator Of Sublethal Stress On Short Time Scales, David Harold Niebuhr

Dissertations, Theses, and Masters Projects

Lipid quality was evaluated in Montastrea spp. under sediment- and heat-stressed conditions to evaluate lipid ratio as an indicator of sub-lethal stress on short time scales. The ratio of storage lipid (wax ester + triacylglyceride) to structural lipid (sterol esters + phospholipid) decreased significantly (0.25 to 0.14, p < 0.01) after experimental sedimentation. FAME analysis of colonies exposed to experimental sedimentation showed a reduction of the algal, 18:3(n-6) and 18:4(n-3), polyunsaturated fatty acid (PUFA) in the polar lipid fraction. This loss of PUFA suggests a loss of algal membrane in sediment-stressed colonies. Lipid quality was similarly measured in M. faveolata over a 10-day period. Mean (n = 20) ratio of storage to structural lipid in M. faveolata dropped from 2.43 to a level of 0.98 immediately following a natural sedimentation event before recovering to levels of 1.4 and 2.9 on post-storm days 2 and 4, respectively. Colonies of M. annularis subject to heat-stress (35??C) exhibited no significant change in storage lipid ratio, while levels of Free Fatty Acids increased significantly from 0.012 (n = 22) to 0.156 mg lipid/g dry tissue (n = 22)(p < 0.05). FAME analysis of tissue lipids extracted from the heat-stressed colonies showed changes in the polar fraction, with significant decreases in the 18:3(n-6), 18:3(n-3), 18:4(n-3), 20:4(n-6) and 20:5(n-3) (p < 0.05) PUFA and subsequent significant increases in the saturated fatty acids, 16:0 and 18:0 (p < 0.05). These changes in lipid quantity and quality indicate possible oxidation and preferential digestion of zooxanthellar membranes. Stress experiments were repeated in M. annularis using VacutainerRTM blood collection tubes to collect micro-tissue samples without destroying skeleton of the sample colonies. A significant decrease in storage: structural lipid ratio after sedimentation was also detected using the micro-tissue technique. This study indicates that the relative abundance of lipid subclass components can indicate sub-lethal environmental stress, on short time scales, in M. annularis and M. faveolata. Furthermore, micro-tissue collection techniques permit repeated monitoring coral colonies to assess the manifestation of stress from first detection of impact at the cellular level to changes in community to changes in community structure detectable over longer time scales.

Bacterial Dynamics And Community Structure In The York River Estuary, Gary Edward Schultz Jr

Dissertations, Theses, and Masters Projects

Bacterial community dynamics were investigated over seasonal and basin scales within the York River, VA, estuary. Various parameters characterizing bacterioplankton dynamics were measured weekly at a single station (March 1996 through May 1997) and monthly at six stations (June 1996 through May 1997) spanning the entire salinity gradient (0 - ca. 20 psu over 60 km). Bacterial abundance and production were found to be high throughout the estuary. Bacterial abundance ranged from 4.4 x 108 to 1.3 x 1010 cells-liter-1Incorporation of 3H-thymidine ranged from 10 to 863 pmol-liter-1-hr-1 while 3H-leucine incorporation rates ranged from 25 to 1963 pmol-liter -1-hr-1. Clear …