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Old Dominion University

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Articles 361 - 390 of 652

Full-Text Articles in Marine Biology

Ocean Warming And Freshening In The Northern Gulf Of Alaska, Thomas C. Royer, Chester E. Grosch Jan 2006

Ocean Warming And Freshening In The Northern Gulf Of Alaska, Thomas C. Royer, Chester E. Grosch

CCPO Publications

Water column temperatures on the shelf in the northern Gulf of Alaska have increased more than 0.8 degrees C and vertical density stratification has increased since 1970 near Seward, Alaska throughout the 250 m depth. This high latitude marine system has low water temperatures, high rates of precipitation, glacial melting, high wind speeds and high rates of biological productivity. A more than 300 km alongshore shift ( locally westward) of isotherms is suggested. The observations are consistent with a conceptual ocean-atmosphere circulation model that employs coastal freshwater discharge, glacial ablation and wind forcing. Positive regional feedback mechanisms accelerate the discharge …

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Effects Of Salinity Changes On The Photodegradation And Ultraviolet-Visible Absorbance Of Terrestrial Dissolved Organic Matter, E. C. Minor, J. Pothen, B. J. Dalzell, H. Abdulla, K. Mopper Jan 2006

Effects Of Salinity Changes On The Photodegradation And Ultraviolet-Visible Absorbance Of Terrestrial Dissolved Organic Matter, E. C. Minor, J. Pothen, B. J. Dalzell, H. Abdulla, K. Mopper

Chemistry & Biochemistry Faculty Publications

We performed laboratory studies to determine the effects of salinity on the photodegradation of dissolved organic matter (DOM) from the Great Dismal Swamp, Virginia, an important source of terrestrial DOM to the lower Chesapeake Bay. Samples were created by mixing Great Dismal Swamp water (ionic strength approximate to 0 mol L-1) with modified artificial seawater solutions of differing salinities while keeping the final dissolved organic carbon (DOC) concentration constant. These samples were then irradiated for 24 h in a light box providing ultraviolet (UV) light similar to that of natural sunlight. Light absorbance and DOC concentrations decreased after …

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Transport Of Antarctic Krill (Euphausia Superba) Across The Scotia Sea. Part Ii: Krill Growth And Survival, Bettina A. Fach, Eileen E. Hofmann, Eugene J. Murphy Jan 2006

Transport Of Antarctic Krill (Euphausia Superba) Across The Scotia Sea. Part Ii: Krill Growth And Survival, Bettina A. Fach, Eileen E. Hofmann, Eugene J. Murphy

CCPO Publications

A time-dependent, size-structured, physiologically based krill growth model was used in conjunction with a circulation model to test the hypothesis that Antarctic krill (Euphausia superba) populations at South Georgia are sustained by import of individuals from upstream regions. Surface phytoplankton concentrations along the simulated drifter trajectories were extracted from historical Coastal Zone Color Scanner (CZCS) measurements and sea ice biota concentrations were calculated from sea ice concentration and extent extracted along drifter trajectories from Special Sensor Microwave/ Imager measurements. As additional food sources, a time series of heterotrophic food was constructed from historical data, and time series of …

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Gis And 3d Analysis Applied To Sea Turtle Mortalities And Navigation Channel Dredging, Bradley A. Shellito, Keith B. Lockwood Jan 2006

Gis And 3d Analysis Applied To Sea Turtle Mortalities And Navigation Channel Dredging, Bradley A. Shellito, Keith B. Lockwood

Virginia Journal of Science

Between 2000 and 2003 there were an increased number of documented sea turtle mortalities related to hopper dredging in the channels of the Chesapeake Bay. A pilot study was undertaken to create a bathymetric surface and three-dimensional model of the Cape Henry Channel using Geographic Information Systems (GIS) as a visualization tool to examine sea turtle mortalities in relation to the dredging. In Fall 2003, the US Army Corps of Engineers dredged the Thimble Shoals Federal Navigation Channel, and a more refined model was developed using this data. This project examines the growing concerns over sea turtle mortality rates and …

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Vertical Distribution Of Decapod Larvae In The Entrance Of An Equatorward Facing Bay Of Central Chile: Implications For Transport, Beatriz Yannicelli, Leonardo R. Castro, Arnoldo Valle-Levinson, Larry Atkinson, Dante Figueroa Jan 2006

Vertical Distribution Of Decapod Larvae In The Entrance Of An Equatorward Facing Bay Of Central Chile: Implications For Transport, Beatriz Yannicelli, Leonardo R. Castro, Arnoldo Valle-Levinson, Larry Atkinson, Dante Figueroa

CCPO Publications

Two short biophysical surveys were carried out in order to assess how the decapod crustacean larvae vertical distribution and circulation patterns in an equatorward facing embayment (Gulf of Arauco, 37° S; 73° W) influenced larval transport into and out of the Gulf. The embayment is located at the upwelling area of south central Chile and features a deep (60 m) and a shallow (25 m) pathway of communication with the adjacent coastal ocean. Profiles of zooplankton, temperature, salinity, dissolved oxygen and current velocity were measured during a 22-h period at the shallow entrance to the gulf. In addition, three zooplankton …

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The Adaptive Value Of Aggregation Among Juvenile Caribbean Spiny Lobster: An Evaluation Using Individual-Based Modeling, Thomas W. Dolan Iii, Mark J. Butler Iv Jan 2006

The Adaptive Value Of Aggregation Among Juvenile Caribbean Spiny Lobster: An Evaluation Using Individual-Based Modeling, Thomas W. Dolan Iii, Mark J. Butler Iv

Biological Sciences Faculty Publications

Ontogenetic changes in gregariousness by pre-reproductive animals, like that observed in juvenile Caribbean spiny lobsters (Panulirus argus), may be adaptive and reflect size-specific changes in the effectiveness of aggregation in promoting survival. Alternatively, aggregation may simply result from changes in the distribution or availability of suitable habitat structure, or from other behaviors that enhance survival. There are currently two hypotheses explaining the potential benefits of gregarious behavior in juvenile spiny lobsters, both of which focus on increasing survivorship by reducing predation pressure: the group benefit hypothesis and the guide hypothesis. The group benefit hypothesis argues that aggregations of …

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Age Validation And Reproductive Biology Of Bluefish, Pomatomus Saltatrix, Along The East Coast Of United States, Eric Robillard Jan 2006

Age Validation And Reproductive Biology Of Bluefish, Pomatomus Saltatrix, Along The East Coast Of United States, Eric Robillard

OES Theses and Dissertations

I describe a new preparation technique that increases readability of otoliths, along with criteria for the interpretation of otolith microstructure of bluefish, Pomatomus saltatrix, collected from Florida to New York during 2001-2003 (n = 2652). I validated annulus formation in otoliths for ages 1 to 8 using marginal increment analysis and thus extended validation by four years to include the preponderance of age classes in the catch. Although otoliths are typically superior for ageing, bluefish are routinely aged with scales; thus a side-by-side comparison of otoliths versus scales is necessary before otoliths can supplant scales. When compared, precision …

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Characterization Of Pfiesteria Ichthyocidal Activity, Andrew S. Gordon, Harold G. Marshall, Sandra E. Shumway, Kathryn J. Coyne, Alan J. Lewitus, Michael A. Mallin, Parke A. Rublee Oct 2005

Characterization Of Pfiesteria Ichthyocidal Activity, Andrew S. Gordon, Harold G. Marshall, Sandra E. Shumway, Kathryn J. Coyne, Alan J. Lewitus, Michael A. Mallin, Parke A. Rublee

Biological Sciences Faculty Publications

Letter to the Editor regarding article: Drgon, T., et al. 2005. Characterization of ichthyocidal activity of Pfiesteria piscicida: Dependence on the dinospore cell density. Appl. Environ. Microbiol. 71:519–529

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Phytoplankton Development Within Tidal Freshwater Regions Of Two Virginia Rivers, Harold G. Marshall, Lubomira Burchardt Jul 2005

Phytoplankton Development Within Tidal Freshwater Regions Of Two Virginia Rivers, Harold G. Marshall, Lubomira Burchardt

Virginia Journal of Science

Phytoplankton composition and the range of seasonal patterns of abundance are presented for the tidal freshwater regions in two Virginia rivers based on data accumulated monthly from 1986 through 1999. Diatoms dominated the flora during spring, summer, and fall, whereas, other taxonomic categories were more representative when the river flow rates decreased, allowing for a more stable water system and increased residency time within this tidal region during summer and early fall. This summer/fall period was associated with increased water temperatures, higher productivity rates and chlorophyll levels, increased total phytoplankton abundance and species diversity. The major components of the summer …

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Variation In The Fluorescence Of Green Fluorescent Protein In Various Strains Of Escherichia Coli, Paul R. Letellier Jr. Jul 2005

Variation In The Fluorescence Of Green Fluorescent Protein In Various Strains Of Escherichia Coli, Paul R. Letellier Jr.

Biological Sciences Theses & Dissertations

Green fluorescent protein (GFP) was first identified in the jellyfish Aequorea victoria and generated interest due to its ability to noninvasively tag and visualize cells, cellular structures, and cellular proteins. Furthermore, the expression of green fluorescent protein in Esherichia coli cells as a tool for reporting gene expression and promotor activity has become important in the understanding of gene regulation. Expression of the gfp gene was found to vary depending on the strain of E. coli possessing the gfp gene. As a result of this fluctuation in fluorescence, gene expression and hence promotor activity may be difficult to detect or …

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Recruitment In Degraded Marine Habitats: A Spatially Explicit, Individual-Based Model For Spiny Lobster, Mark J. Butler Iv, Thomas W. Dolan Iii, John H. Hunt, Kenneth A. Rose, William F. Herrnkind Jun 2005

Recruitment In Degraded Marine Habitats: A Spatially Explicit, Individual-Based Model For Spiny Lobster, Mark J. Butler Iv, Thomas W. Dolan Iii, John H. Hunt, Kenneth A. Rose, William F. Herrnkind

Biological Sciences Faculty Publications

Coastal habitats that serve as nursery grounds for numerous marine species are badly degraded, yet the traditional means of modeling populations of exploited marine species handle spatiotemporal changes in habitat characteristics and life history dynamics poorly, if at all. To explore how nursery habitat degradation impacts recruitment of a mobile, benthic species, we developed a spatially explicit, individual-based model that describes the recruitment of Caribbean spiny lobster (Panulirus argus) in the Florida Keys, where a cascade of environmental disturbances has reconfigured nursery habitat structure. In recent years, the region has experienced a series of linked perturbations, among them, seagrass die-offs, …

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Morphological And Molecular Defects In Zebrafish Embryos (Danio Rerio) After Chromated Copper Arsenate Exposure, Kerry Jean Lee Apr 2005

Morphological And Molecular Defects In Zebrafish Embryos (Danio Rerio) After Chromated Copper Arsenate Exposure, Kerry Jean Lee

Biological Sciences Theses & Dissertations

This investigation identified the morphological defects caused by different concentrations of chromium, copper, and arsenic (CCA) on the developing zebrafish embryo; in addition to defects caused by the three combined components (complete CCA). A change in the DNA of the developing embryos in response to the three components of CCA and complete CCA was also determined. Early Dania rerio embryos were cultured for five days with various concentrations of CCA components and complete CCA. Morphological defects were assessed with light microscopy and DNA fragmentation was determined by agarose gel electrophoresis. Embryonic exposure of D. rerio to sub lethal concentrations of …

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Feeding Behavior And Conditioning In Two Heterotrophic Dinoflagellates, Todd A. Egerton Apr 2005

Feeding Behavior And Conditioning In Two Heterotrophic Dinoflagellates, Todd A. Egerton

Biological Sciences Theses & Dissertations

Growth and abundance of heterotrophic dinoflagellate predators are generally attributed to the availability of algal prey. Several species of dinoflagellates feed on a wide variety of food types including fish. However the actual feeding preferences of dinoflagellates have been much less studied. In the few studies that have been carried out on dinoflagellate feeding preference, none have looked at possible factors that may affect preference. I conducted three experiments on the toxic dinoflagellate Pfiesteria piscicida and the related unnamed species Cryptoperidiniopsis brodyi which, (1) calculated the feeding preferences between algal Rhodomonas prey and fish blood cells and identified factors that …

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Iron In The Sargasso Sea (Bermuda Atlantic Time-Series Study Region) During Summer: Eolian Imprint, Spatiotemporal Variability, And Ecological Implications, Peter N. Sedwick, T. M. Church, A. R. Bowie, C. M. Marsay, S. J. Ussher, K. M. Achilles, P. J. Lethaby, R. J. Johnson, M. M. Sarin, D. J. Mcgillicuddy Jan 2005

Iron In The Sargasso Sea (Bermuda Atlantic Time-Series Study Region) During Summer: Eolian Imprint, Spatiotemporal Variability, And Ecological Implications, Peter N. Sedwick, T. M. Church, A. R. Bowie, C. M. Marsay, S. J. Ussher, K. M. Achilles, P. J. Lethaby, R. J. Johnson, M. M. Sarin, D. J. Mcgillicuddy

OES Faculty Publications

We report iron measurements for water column and aerosol samples collected in the Sargasso Sea during July-August 2003 (summer 2003) and April-May 2004 (spring 2004). Our data reveal a large seasonal change in the dissolved iron (dFe) concentration of surface waters in the Bermuda Atlantic Time-series Study region, from ∼1-2nM in summer 2003, when aerosol iron concentrations were high (mean 10 nmol/m-3), to ∼0.1-0.2nM in spring 2004, when aerosol iron concentrations were low (mean 0.64 nmol/m-3). During summer 2003, we observed an increase of ∼0.6nM in surface water dFe concentrations over 13 days, presumably due to …

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A Unique Seasonal Pattern In Phytoplankton Biomass In Low-Latitude Waters In The South China Sea, Chun-Mao Tseng, George T. F. Wong, I.-I. Lin, C.-R. Wu, K.-K. Liu Jan 2005

A Unique Seasonal Pattern In Phytoplankton Biomass In Low-Latitude Waters In The South China Sea, Chun-Mao Tseng, George T. F. Wong, I.-I. Lin, C.-R. Wu, K.-K. Liu

OES Faculty Publications

A distinctive seasonal pattern in phytoplankton biomass was observed at the South East Asian Time series Study (SEATS) station (18°N, 116°E) in the northern South China Sea (SCS). Surface chlorophyll-a, depth integrated chlorophyll-a and primary production were elevated to 0.3 mg/m3, ~35 mg/m2 and 300 mg-C/m2/d, respectively, in the winter but stayed low, at 0.1 mg/m3, ~15 mg/m2 and 110 mg-C/m2/d as commonly found in other low latitude waters, in the rest of the year. Concomitantly, soluble reactive phosphate and nitrate+nitrite in the mixed layer also became …

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Biophysical Mechanisms Of Larval Fish Ingress Into Chesapeake Bay, Jonathan A. Hare, Simon Thorrold, Harvey Walsh, Christian Reiss, Arnoldo Valle-Levinson, Cynthia Jones Jan 2005

Biophysical Mechanisms Of Larval Fish Ingress Into Chesapeake Bay, Jonathan A. Hare, Simon Thorrold, Harvey Walsh, Christian Reiss, Arnoldo Valle-Levinson, Cynthia Jones

OES Faculty Publications

Selective tidal stream transport is hypothesized as a dominant mechanism by which larvae of marine animals move through estuarine openings. For larvae moving from the shelf to estuarine habitats, selective tidal stream transport proposes that larvae are higher in the water column during flood tide and lower in the water column during ebb tide. Although a number of studies conclude that selective tidal stream transport is the mechanism responsible for larval ingress, few studies consider alternative mechanisms or consider passive explanations for tidal patterns in larval distributions. We examined the biophysical mechanisms responsible for larval ingress into Chesapeake Bay using …

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Do Viruses Affect Fecundity And Survival Of The Copepod Acartia Tonsa Dana?, Lisa A. Drake, Fred C. Dobbs Jan 2005

Do Viruses Affect Fecundity And Survival Of The Copepod Acartia Tonsa Dana?, Lisa A. Drake, Fred C. Dobbs

OES Faculty Publications

Naturally occurring viruses are extremely abundant in aquatic systems, and they infect bacteria, cyanobacteria, prokaryotic and eukaryotic phytoplankton, heterotrophic nanoflagellates, fish and mammals. Viral infections of single-celled organisms have been studied intensively in the past decade, but little is known about the effects of viruses on aquatic metazoans, other than for some economically important species. Because zooplankton assemblages are often dominated in number and biomass by copepods, we used them as model organisms to study the effects of naturally occurring viruses on higher trophic levels. We attempted to induce viral infection in laboratory-reared cultures of the estuarine copepod Acartia tonsa …

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The Effect Of Growth Rate, Phosphorus Concentration, And Temperature On N-2 Fixation, Carbon Fixation, And Nitrogen Release In Continuous Cultures Of Trichodesmium Ims101, Margaret R. Mulholland, Peter W. Bernhardt Jan 2005

The Effect Of Growth Rate, Phosphorus Concentration, And Temperature On N-2 Fixation, Carbon Fixation, And Nitrogen Release In Continuous Cultures Of Trichodesmium Ims101, Margaret R. Mulholland, Peter W. Bernhardt

OES Faculty Publications

With the use of continuous culture systems, rates of dinitrogen (N2) and carbon (C) fixation and nitrogen (N)- and C-based doubling times were assessed in Trichodesmium IMS101 growing exponentially at steady state dilution rates of 0.10, 0.20, and 0.33 d-1 (doubling times of 10, 5, and 3 d - within the range reported for natural populations). Rates of C fixation, N2 fixation, and N release were examined in replicate culture systems with several techniques. Biomass-specific C uptake varied little with population doubling time, but N2 fixation and N release varied markedly among treatments. Total daily …

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Body-Induced Vortical Flows: A Common Mechanism For Self-Corrective Trimming Control In Boxfishes, Ian K. Bartol, Morteza Gharib, Paul W. Webb, Daniel Weihs, Malcolm S. Gordon Jan 2005

Body-Induced Vortical Flows: A Common Mechanism For Self-Corrective Trimming Control In Boxfishes, Ian K. Bartol, Morteza Gharib, Paul W. Webb, Daniel Weihs, Malcolm S. Gordon

Biological Sciences Faculty Publications

Boxfishes (Teleostei: Ostraciidae) are marine fishes having rigid carapaces that vary significantly among taxa in their shapes and structural ornamentation. We showed previously that the keels of the carapace of one species of tropical boxfish, the smooth trunkfish, produce leading edge vortices (LEVs) capable of generating self-correcting trimming forces during swimming. In this paper we show that other tropical boxfishes with different carapace shapes have similar capabilities. We conducted a quantitative study of flows around the carapaces of three morphologically distinct boxfishes (spotted boxfish, scrawled cowfish and buffalo trunkfish) using stereolithographic models and three separate but interrelated analytical …

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A Review Of Phytoplankton Composition Within Chesapeake Bay And Its Tidal Estuaries, Harold G. Marshall, Lubomira Burchardt, Richard Lacouture Jan 2005

A Review Of Phytoplankton Composition Within Chesapeake Bay And Its Tidal Estuaries, Harold G. Marshall, Lubomira Burchardt, Richard Lacouture

Biological Sciences Faculty Publications

Based on a continuous 20-year data base ofmonthly sampling in Chesapeake Bay and tidal regions of its major tributaries, 1454 phytoplankton taxa have been identified in these waters. They represent a diverse assemblage of species with a dominant diatom flora throughout the year, in addition to large seasonal representation by chlorophytes, cyanobacteria, cryptophytes and dinoflagellates. Included among this flora were 34 potential harmful or toxin producing species. The phytoplankton compositions associated with the seasonal successional patterns are discussed, in addition to characterizing the dominant floral relationships, with comparison to early composition records within the Bay. Several of the present day …

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Benthic Fisheries Ecology In A Changing Environment: Unraveling Process To Achieve Prediction, Mark J. Butler Iv Jan 2005

Benthic Fisheries Ecology In A Changing Environment: Unraveling Process To Achieve Prediction, Mark J. Butler Iv

Biological Sciences Faculty Publications

Marine fisheries and the ecosystems that sustain them are increasingly beset by environmental deterioration, and the problem is particularly acute in coastal zones where human Populations are increasing. In the best of circumstances, fishery managers are faced with the multiple, often conflicting, demands of resource users, politicians, and scientists when considering strategies for resource management. A further challenge is that management decisions must be made against a backdrop of a deteriorating environment and the shifting status of coastal ecosystem integrity. Traditional tools for single-species management may be inadequate in these settings. Furthermore. the necessary empirical data to appropriately parameterize models …

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Can Otolith Elemental Signatures Record The Capture Site Of Patagonian Toothfish (Dissostichus Eleginoides), A Fully Marine Fish In The Southern Ocean?, J. R. Ashford, C. M. Jones, E. Hofmann, I. Everson, C. Moreno, G. Duhamel, R. Williams Jan 2005

Can Otolith Elemental Signatures Record The Capture Site Of Patagonian Toothfish (Dissostichus Eleginoides), A Fully Marine Fish In The Southern Ocean?, J. R. Ashford, C. M. Jones, E. Hofmann, I. Everson, C. Moreno, G. Duhamel, R. Williams

CCPO Publications

Otolith chemistry has been successfully used to reconstruct the environmental history experienced by estuarine-dependent teleost fish, including movement between estuaries and coastal areas. However, application has been more limited in species exposed exclusively to oceanic waters, where gradients in physical and chemical properties are less extreme. To test whether otolith elemental signatures record spatial information in an oceanic species, we sampled otoliths from Patagonian toothfish (Dissostichus eleginoides) and used an inductively coupled plasma mass spectrometer (ICP-MS) coupled to a laser ablation system to target the outer otolith edges corresponding to the period immediately before capture. Using multivariate analysis …

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The Role Of Feeding Behavior In Sustaining Copepod Populations In The Tropical Ocean, J. D. Wiggert, A. G. E. Haskell, G.-A. Paffenhofer, E. E. Hofmann, J. M. Klinck Jan 2005

The Role Of Feeding Behavior In Sustaining Copepod Populations In The Tropical Ocean, J. D. Wiggert, A. G. E. Haskell, G.-A. Paffenhofer, E. E. Hofmann, J. M. Klinck

CCPO Publications

A fundamental question regarding marine copepods is how the many species coexist and persist in the oligotrophic environment (i.e. Hutchinson’s paradox). This question is addressed with a stochastic, object-oriented Lagrangian model that explicitly simulates the distinct foraging behaviors of three prominent tropical species: Clausocalanus furcatus, Paracalanus aculeatus and Oithona plumifera. The model also individually tracks all prey cells. Each particle’s motion combines sinking, turbulent diffusion and active swimming when applicable. The model successfully simulates observed size partitioned carbon uptake rates. Based on the model results, the wide-ranging translational ambit employed by C. furcatus is best suited for the acquisition …

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Feeding Ecology Of Juvenile Spiny Lobster, Panulirus Interruptus, On The Pacific Coast Of Baja California Sur, Mexico, Verónica Castañeda‐Fernández‐De‐Lara, Elisa Serviere‐Zaragoza, Sergio Hernández‐Vázquez, Mark J. Butler Iv Jan 2005

Feeding Ecology Of Juvenile Spiny Lobster, Panulirus Interruptus, On The Pacific Coast Of Baja California Sur, Mexico, Verónica Castañeda‐Fernández‐De‐Lara, Elisa Serviere‐Zaragoza, Sergio Hernández‐Vázquez, Mark J. Butler Iv

Biological Sciences Faculty Publications

Many aspects of the early life history of the red lobster Panulirus interruptus are little known, including the relationship between habitat structure, food resource availability, and nutrition of juveniles. We investigated the spatial and temporal differences in food intake, diet composition, and nutritional condition of juveniles at two sites along the Pacific coast of the Baja California Peninsula (Mexico) with contrasting oceanographic and biological conditions. One site (Arvin) is located inside a protected bay, Bahia Tortugas, where the waters are cooler and temperate seagrasses and macroalgae are the dominant benthic flora. The second site (Queen) in Bahia Sebastian Vizcaino was …

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Phytoplankton Development Within Tidal Freshwater Regions Of Two Virginia Rivers, Usa, Harold G. Marshall, Lubomira Burchardt Jan 2005

Phytoplankton Development Within Tidal Freshwater Regions Of Two Virginia Rivers, Usa, Harold G. Marshall, Lubomira Burchardt

Biological Sciences Faculty Publications

Phytoplankton composition and the range of seasonal patterns of abundance are presented for the tidal freshwater regions in two Virginia rivers based on data accumulated monthly from 1986 through 1999. Diatoms dominated the flora during spring, summer, and fall, whereas, other taxonomic categories were more representative when the river flow rates decreased, allowing for a more stable water system and increased residency time within this tidal region during summer and early fall. This summer/fall period was associated with increased water temperatures, higher productivity rates and chlorophyll levels, increased total phytoplankton abundance and species diversity. The major components of the summer …

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Demonstration Of Toxicity To Fish And To Mammalian Cells By Pfiesteria Species: Comparison Of Assay Methods And Strains, Joann M. Burkholder, Andrew S. Gordon, Peter D. Moeller, J. Mac Law, Kathryn J. Coyne, Alan J. Lewitus, John S. Ramsdell, Harold G. Marshall, Nora J. Deamer, S. Craig Cary, Jason W. Kempton, Steven L. Morton, Parke A. Rublee Jan 2005

Demonstration Of Toxicity To Fish And To Mammalian Cells By Pfiesteria Species: Comparison Of Assay Methods And Strains, Joann M. Burkholder, Andrew S. Gordon, Peter D. Moeller, J. Mac Law, Kathryn J. Coyne, Alan J. Lewitus, John S. Ramsdell, Harold G. Marshall, Nora J. Deamer, S. Craig Cary, Jason W. Kempton, Steven L. Morton, Parke A. Rublee

Biological Sciences Faculty Publications

Toxicity and its detection in the dinoflagellate fish predators Pfiesteria piscicida and Pfiesteria shumwayae depend on the strain and the use of reliable assays. Two assays, standardized fish bioassays (SFBs) with juvenile fish and fish microassays (FMAs) with larval fish, were compared for their utility to detect toxic Pfiesteria. The comparison included strains with confirmed toxicity, negative controls (noninducible Pfiesteria strains and a related nontoxic cryptoperidiniopsoid dinoflagellate), and P. shumwayae strain CCMP2089, which previously had been reported as nontoxic. SFBs, standardized by using toxic Pfiesteria (coupled with tests confirming Pfiesteria toxin) and conditions conducive to toxicity expression, reliably detected …

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New Species Of Amphipod Crustaceans In The Genera Tegano And Melita (Hadzioidea : Melitidae) From Subterranean Groundwaters In Guam, Palau, And The Philippines, Thomas R. Sawicki, John R. Holsinger, Thomas M. Iliffe Jan 2005

New Species Of Amphipod Crustaceans In The Genera Tegano And Melita (Hadzioidea : Melitidae) From Subterranean Groundwaters In Guam, Palau, And The Philippines, Thomas R. Sawicki, John R. Holsinger, Thomas M. Iliffe

Biological Sciences Faculty Publications

Three new species of Tegano are described, two from caves on Panglao Island, Bohol, Philippines, and one from a cave on Peleliu Island, Palau. Sriha vagabunda from Sri Lanka is reassigned to the genus Tegano based primarily on the high degree of similarity between Sriha vagabunda and species of Tegano and the fact that these species exhibit a great deal of variation in the reduction of the mandibular palp. A new species of Melita with characters intermediate between those defining the genera Abludomelita, Melita, and Paraniphargus is described from a spring on Guam. The characters of the new …

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Strong Interactions Between Juvenile Caribbean Spiny Lobster (Panulirus Argus) And Caribbean Reef Octopus (Octopus Briareus) In The Florida Keys, Jennifer Anne Lear Oct 2004

Strong Interactions Between Juvenile Caribbean Spiny Lobster (Panulirus Argus) And Caribbean Reef Octopus (Octopus Briareus) In The Florida Keys, Jennifer Anne Lear

Biological Sciences Theses & Dissertations

Coexisting species may simultaneously compete for resources and interact as predator and prey, creating a strong interaction that can alter the structure of animal communities. This type of interaction potentially occurs between juvenile Caribbean spiny lobster (Panulirus argus) and Caribbean reef octopus (Octopus briareus) within hard-bottom habitats in the Florida Keys, FL (USA), where octopuses may consume juvenile lobsters and also compete with them for limited crevice shelters. I conducted a series of field and mesocosm studies to investigate the nature of octopus-lobster interactions and their implications for the structure of their populations in the wild. …

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A Phylogeny Of Genera Of The Fish Family Nemipteridae (Percoidei) Based On The Cytochrome B Gene, Denise R. Sliter Oct 2004

A Phylogeny Of Genera Of The Fish Family Nemipteridae (Percoidei) Based On The Cytochrome B Gene, Denise R. Sliter

Biological Sciences Theses & Dissertations

The species level taxonomy of the Nemipteridae is well understood but existing morphological data is insufficient to hypothesize a phylogeny of the five genera of this family of percoid fishes. Furthermore, there are three distinct and widely disparate habitat requirements within nemipterids and little is known how these evolved. Species in the genera Pentapodus, Scaevius and Scolopsis are typically found around shallow reefs. Nemipterus species are also found in shallow-water, but they inhabit strictly soft sediment bottoms. Parascolopsis is the only deep-water genus and its species are also found over soft sediments. Complete cytochrome b gene sequences (1140 base …

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Relating Water And Otolith Chemistry In Chesapeake Bay, And Their Potential To Identify Essential Seagrass Habitats For Juveniles Of An Estuarine-Dependent Fish, Spotted Seatrout (Cynoscion Nebulosus), Emmanis Dorval Apr 2004

Relating Water And Otolith Chemistry In Chesapeake Bay, And Their Potential To Identify Essential Seagrass Habitats For Juveniles Of An Estuarine-Dependent Fish, Spotted Seatrout (Cynoscion Nebulosus), Emmanis Dorval

Biological Sciences Theses & Dissertations

A quantitative understanding of habitat use of estuarine-dependent fishes is critical to the conservation of their most essential habitats. Because recruitment and fitness may be influenced by the quality of juvenile habitats, developing methods to quantify habitat-specific survivorship is pivotal to such understanding. An initial step to quantify survivorship is to validate the habitat-specific natural tags contained in otoliths. To this aim I investigated the variability in the chemistry of surface waters and otoliths of juvenile spotted seatrout, Cynoscion nebulosus, in five seagrass habitats of Chesapeake Bay, namely: Potomac, Rappahannock, York, Island, and Eastern Shore. I measured Mg, Ca, …

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