Life Sciences Commons^™

Summer 1999, Nsu Oceanographic Center

Currents

No abstract provided.

Use Of Extractable Lipofuscin For Age Determination Of Blue Crab Callinectes Sapidus, Se-Jong Ju, David H. Secor, H. Rodger Harvey

OES Faculty Publications

The blue crab Callinectes sapidus is an economically and ecologically important species in many temperate estuaries, yet stock assessments have been limited to length-based methods for demographic analyses. We evaluated the potential of age pigments (lipofuscins) sequestered in neural tissue of eye-stalks and brains to estimate the age of blue crabs collected from Chesapeake Bay and Chincoteague Bay. The rate of lipofuscin accumulation was determined using crabs of known age reared in the laboratory. Age pigments were extracted from neural tissues (eye-stalk or brain), quantified, and normalized to protein content to allow comparisons across tissue types and crab sizes. Field-collected …

Comments On "On The Utility And Disutility Of Jebar" - Reply, Mark A. Cane, Vladimir M. Kamenkovich

Faculty Publications

No abstract provided.

Draft Shark Bay Pink Snapper Management Plan 1999, Fisheries Western Australia.

Fisheries management papers

This draft management plan was prepared by the Fisheries Department on 12 July 1999 for the Minister for Fisheries for the purpose of facilitating consultation in resepct of the proposal by the Minister to determine a new Management Plan for the Shark Bay Pink Snapper Fishery.

Age And Growth Of Cobia, Rachycentron Canadum, From The Northeastern Gulf Of Mexico, James S. Franks, James R. Warren, Michael V. Buchanan

Faculty Publications

We examined 1005 cobia, Rachycentron canadum, from recreational catches in the northeastern Gulf of Mexico from 1987 to 1995. Specimens ranged from 325 to 1651 mm fork length (FL); females had a mean FL of 1050 mm (n=730) and were significantly larger than males that had a mean FL of 952 mm (n=275). The over all male to female ratio was 1:2.7. Ages of 565 cobia were estimated from thin-sectioned otoliths (sagittae). Marginal-increment analysis of sagittal otoliths showed a single annual minimum during June. Male cobia (n=170; 525-1330 mm FL) ranged from age 0 to 9, and females (n=395; 493-1651 …

The Crest, Summer 1999, Virginia Institute Of Marine Science

Reports

Table of Contents:

• New Research Aquarium System
• Finfish Aquaculture at VIMS
• Virginia Creates State Research Reserve System
• Pollution-Laden Sediments In Constant Flux
• Survey of Mid-Atlantic Sea Scallop Closed Areas
• Pfiesteria Update
• New Computer Program Helps Planners Balance Growth, Protection
• Virginia Sea Grant to Administer Commercial Fishery Resource Program
• VIMS Stranded Sea Turtle Project Underway Coastal Sediments Offer Clues to Climate Change, Pollution
• Seemingly Barren Habitat Proves Vital for Economically Important Virginia Fish (juvenile flounder)

Blue Crab Larval Dispersion And Retention In The Mississippi Bight, Donald R. Johnson, Harriet M. Perry

Faculty Publications

A conceptual hypothesis relating physical forcing to dispersion and retention was developed for blue crab larvae within the Mississippi Eight. The spawning period for blue crabs in the northern Gulf of Mexico is protracted. Hatching of eggs occurs near the barrier islands and mouths of coastal bays from March through October. Larvae are released on ebbing tides and spend the next 30 to 50 d offshore where they develop through seven zoeal stages before undergoing metamorphosis to megalopae. Duration of the megalopal stage is variable but generally persists from 6 to 20 d. Blue crabs recruit to Gulf estuaries as …

Encystment, Excystment And Photosynthetic Activity In The Temporary Cysts Of Amphidinium Carterae, Steven R. Kibler

OES Theses and Dissertations

Although the formation of temporary cysts has been documented in several papers, the physiology of these stages has remained obscure. Research dealing with dinoflagellate resting stages has primarily targeted sexual cysts. Accordingly, formation, germination and photosynthetic activity in the temporary cysts of Amphidinium carterae have been investigated in the present study. The effect of light intensity upon cyst germination was tested by incubating temporary cysts at three different light intensities. In order to assess the potential for photosynthesis in cysts, cellular chlorophyll-a concentrations and cellular fluorescence were quantified during encystment. Photosynthetic carbon uptake of H¹⁴CO₃^- was …

Molecular Techniques Reveal Wide Phyletic Diversity Of Heterotrophic Microbes Associated With Discodermia Spp. (Porifera: Demospongiae), Jose V. Lopez, Peter J. Mccarthy, Kathleen E. Janda, Robin Willoughby, Shirley A. Pomponi

Marine & Environmental Sciences Faculty Articles

Sponges are well known to harbor large numbers of heterotrophic microbes within their mesohyl. Studies to determine the diversity of these associated microbes have been attempted for only a few shallow water species. We cultured various microorganisms from several species of Discodermia collected from deep water using the 'Johnson-Sea-Link' manned submersibles, and characterised them by standard microbiological identification methods. Characterisation of a small proportion (ca. 10%) of the total and potential eubacterial isolate collection with molecular systematics techniques revealed a wide diversity of microbes. Phylogenetic analyses of 32 small subunit (SSU) 16S-like rRNA gene sequences from different micorbes indicated high …

West Florida Shelf Response To Upwelling Favorable Wind Forcing: Kinematics, Zhenjiang Li, Robert H. Weisberg

Marine Science Faculty Publications

The barotropic responses of the west Florida continental shelf to idealized upwelling favorable alongshore and offshore wind stresses are studied using the three-dimensional, time-dependent, primitive equation Princeton Ocean Model (POM). When forced with uniform winds, the shelf circulation evolves quickly to a quasi steady state. A southeastward alongshore wind lowers sea level along the coast and drives a southeastward coastal jet with a relatively weak northwestward return flow farther offshore. A southwestward offshore wind lowers sea level along the west Florida coast and raises sea level along the Panhandle coast. Two independent circulation gyres are set up in association with …

Local Data Assimilation In The Estimation Of Barotropic And Baroclinic Open Boundary Conditions, Igor Shulman, James K. Lewis, John G. Mayer

Faculty Publications

The problem of data assimilation in the specification of open boundary conditions for limited area models is addressed in this paper. Optimization approaches are detailed, which are based on combining available data on an open boundary with the physics of the hydrodynamical model. In our case the physics is in terms of the flux of energy through the open boundary. These optimized boundary conditions, for both barotropic and baroclinic situations, interpreted physically as special Linearizations of the Bernoulli equation for each normal mode. Because of the complexity of decomposing variables into normal modes for open boundaries with varying bathymetry, we …

Fish Species Richness In Relation To Restored Oyster Reefs, Piankatank River, Virginia, Jm Harding, Roger L. Mann

VIMS Articles

Fish assemblages in relation to “reef” structures in marine habitats have been and continue to be topics for research addressing ecological and management questions. Much effort has been spent describing and defining fish assemblages, or groups of species, associated with tropical coral reefs (e.g., Sale 1991 and chapters therein), temperate hard bottom or rocky reefs (e.g., Sedberry and Van Dolah, 1984; Ambrose and Swarbrick, 1989), tropical lava flows (e.g., Godwin and Kosaki, 1989), and artificial “fishing” reefs (e.g., Chandler et al., 1985; Hueckel and Buckley, 1987; Bohnsack, 1989; Feigenbaum et al., 1989; Rountree, 1989; Stephan and Lindquist, 1989). Temperate oyster …

A Preliminary Study Of Predation On Blue Crabs By Three Fish Predators In A Seagrass Bed, R J. Orth, Jacques Van Montfrans, James Fishman

Reports

This report serves as a preliminary assessment of potential feeding impacts on blue crab prey inhabiting a seagrass bed in the York River by three species of recreationally and commercially important fish (striped bass, croaker, and red drum). We also provide an historic perspective indicating possible changes in relative abundance of these predatory fish between the period 1978-1980 and 1998. In no way do we intend for this report to reflect an accurate, bay-wide assessment of these relationships; the extremely limited temporal and spatial scope of this effort precludes such conclusions. However, this report supports the contention that habitat-specific predation …

Adaptive Strategies That Reduce Predation On Caribbean Spiny Lobster Postlarvae During Onshore Transport, Charles A. Acosta, Mark J. Butler Iv

Biological Sciences Faculty Publications

Like many marine species with meroplanktonic larvae, the Caribbean spiny lobster (Panulirus argus) has a postlarval stage that moves from the oceanic plankton to inshore nurseries only under specific environmental conditions (i.e., at night, in the surface water layer, on the flood tide, and during new moon), presumably to avoid predation or to enhance onshore transport. Using held and mesocosm experiments, we compared predation on planktonic postlarvae swimming at night near the surface and bottom over coastal habitats along typical offshore-inshore transport paths and determined whether predation rates differed between lunar periods (new moon vs, full moon) and with prey …

Simulation Of Carbon-Nitrogen Cycling During Spring Upwelling In The Cariaco Basin, John J. Walsh, Dwight A. Dieterle, Frank E. Muller-Karger, Richard Bohrer, W. Paul Bissett, Ramon J. Varela, Ruben Aparicio, Rafael Diaz, Robert Thunell, Gordon T. Taylor, Mary I. Scranton, Kent A. Fanning, Edward T. Peltzer

Marine Science Faculty Publications

Coupled biological-physical models of carbon-nitrogen cycling by phytoplankton, zooplankton, and bacteria assess the impacts of nitrogen fixation and upwelled nitrate during new production within the shelf environs of the Cariaco Basin. During spring upwelling in response to a mean wind forcing of 8 m s(-1), the physical model matches remote-sensing and hydrographic estimates of surface temperature. Within the three-dimensional flow field, the steady solutions of the biological model of a simple food web of diatoms, adult calanoid copepods, and ammonifying/nitrifying bacteria approximate within similar to 9% the mean spring observations of settling fluxes caught by a sediment trap at similar …

Spring 1999, Nsu Oceanographic Center

Currents

No abstract provided.

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 …

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 …

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 …

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 …

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 …

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 …

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 …