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Full-Text Articles in Life Sciences

Humoral Defense Factors In Marine Bivalves, Fu-Lin E. Chu Jan 1988

Humoral Defense Factors In Marine Bivalves, Fu-Lin E. Chu

VIMS Books and Book Chapters

Natural humoral components have been discovered and described in hemolymph from several marine bivalve species including eastern oyster Crassostrea virginica, blue mussel Mitilus edulis, northern quahog Mercenaria mercenaria, softshell Mya arenaria, and Pacific oyster Crassostrea gigas, These hemolymph components are enzymes of lysosomal origin, agglutinins, lectins, hemolysin, and antimicrobial substances, These components are proteins or glycoproteins found in the serum, hemocytes, or both, The exact relationship of these substances to the internal defense of marine bivalves against parasites and pathogenic microorganisms is not known. Lysosomal enzymes seem to have a double role, defense and nutrition. The free- and cell-bound lectins …


Structure Of Protistan Parasites Found In Bivalve Molluscs, Frank O. Perkins Jan 1988

Structure Of Protistan Parasites Found In Bivalve Molluscs, Frank O. Perkins

VIMS Books and Book Chapters

The literature on the structure of protists parasitizing bivalve molluscs is reviewed, and previously unpublished observations of species of class Perkinsea , phylum Haplosporidia, and class Paramyxea are presented. Descriptions are given of the flagellar apparatus of Perkinsus marinus zoospores, the ultrastructure of Perkinsus sp. from the Baltic macoma Macoma balthica, and the development of haplosporosome-like bodies in Haplosporidium nelsoni. The possible origin of stem cells of Marrteilia sydneyi from the inner two sporoplasms is discussed. New research efforts are suggested which could help elucidate the phylogenetic interrelationships and taxonomic positions of the various taxa and help in efforts to …


Epizootiology Of The Disease Caused By The Oyster Pathogen Perkinsus Marinus And Its Effects On The Oyster Industry, Jay D. Andrews Jan 1988

Epizootiology Of The Disease Caused By The Oyster Pathogen Perkinsus Marinus And Its Effects On The Oyster Industry, Jay D. Andrews

VIMS Books and Book Chapters

Perkinsus marinus is a protozoan parasite that causes a major disease of eastern oysters Crassostrea virginica from Chesapeake Bay south along the Atlantic coast of the USA and throughout the Gulf of Mexico. It is a warm-season disease that kills eastern oysters at temperatures above 20°C. The pathogen requires salinities of at least 12-15%0 to be active, but it persists tenaciously when low temperatures and salinities occur during winter and spring. Prolonged droughts that increase salinities cause extensions of the range of disease. In the Chesapeake Bay, mortalities begin in June and end in October, and up to 50% of …


Submerged Aquatic Vegetation In Delaware's Inland Bays, Robert J. Orth, Kenneth A. Moore Jan 1988

Submerged Aquatic Vegetation In Delaware's Inland Bays, Robert J. Orth, Kenneth A. Moore

VIMS Books and Book Chapters

Submerged aquatic vegetation (SAV) is an important living resource in many coastal areas throughout the world. These plant communities have been cited as some of the most biologically important in the world. ...


Submerged Aquatic Vegetation In The Chesapeake Bay: A Barometer Of Bay Health, Robert J. Orth, Kenneth A. Moore Jan 1988

Submerged Aquatic Vegetation In The Chesapeake Bay: A Barometer Of Bay Health, Robert J. Orth, Kenneth A. Moore

VIMS Books and Book Chapters

In 1978, a program was initiated in the Chesapeake Bay region to investigate the decline of submerged aquatic vegetation (SA V), potential factors that may have led to its decline, its distribution and abundance, and its .role and value. The program began with little available background data, but some very basic questions about SAV in the Bay were answered in the approximately three years of research that were funded. For example, it was determined that the decline of SAV was Baywide. All SA V species were affected and the decline was unprecedented in the recent history of the Bay. A …


Some Histologic Gill Lesions Of Several Estuarine Finfishes Related To Exposure To Contaminated Sediments: A Preliminary Report, W. J. Hargis Jr., D. E. Zwerner Jan 1988

Some Histologic Gill Lesions Of Several Estuarine Finfishes Related To Exposure To Contaminated Sediments: A Preliminary Report, W. J. Hargis Jr., D. E. Zwerner

VIMS Books and Book Chapters

Collections were made during 1983, '84 and '85 in the Elizabeth River, whose sediments are heavily contaminated with PAHs, heavy metals and other anthropogenic materials. Comparison samples were from the "cleaner" Nansemond River, another subestuary feeding into Hampton Roads (the lower James River) nearby. Most samples from all stations included three transient quasi-catadromous nektonic sciaenids, Atlantic croaker (Micropogonias undulatus), spot (Leiostomus xanthurus) and weakfish (Cynoscion regalis), and two endemic estuarine benthic fishes, hogchoker (Trinectes maculatus) and oyster toadfish (Opsanus tau).


Comparison Of Sediment Landscapes In Chesapeake Bay As Seen By Surface And Profile Imaging, Robert J. Diaz, Linda C. Schaffner Jan 1988

Comparison Of Sediment Landscapes In Chesapeake Bay As Seen By Surface And Profile Imaging, Robert J. Diaz, Linda C. Schaffner

VIMS Books and Book Chapters

The sediment-water interface is the boundary layer between the water column and sediments. It is involved in virtually all processes and cycles within aquatic and estuarine ecosystems. Interactions and reactions at the sediment-water interface are of particular importance in regulating processes involving nutrient regeneration-remineralization (Boynton and Kemp 1985), fate of toxicants (Olsen, Cutshall and Larsen 1982), development of hypoxia-anoxia (Garber 1987), sediment mixing (Schaffner et al. 1987a, b), and sediment transport (Wright et al. 1987). Much effort has and is being expended to provide details of these processes which will eventually be used in management plans for water quality, sediment …


Bioavailability Of Organic Pollutants To Aquatic Organisms, Robert C. Hale, Robert J. Huggett Jan 1988

Bioavailability Of Organic Pollutants To Aquatic Organisms, Robert C. Hale, Robert J. Huggett

VIMS Books and Book Chapters

Settlement of the Chesapeake Bay region began in earnest in the early 17th century. The native American population and early colonists were impressed by the abundance of fish and shellfish and located their population centers to take advantage of these and other natu!al resources. Introduction of wastes into the bay was coincident with this settlement. As the human population increased, so did the pressure on the ecological system. In the 20th century significant quantities of synthetic chemicals began to be introduced, many of which were toxic and nonbiodegradable [Faust and Hunter 1971]. Today the areas surrounding the bay are experiencing …


A Mark-Recapture Study Of Striped Bass In The Rappahannock River, Virginia Annual Report 1987-1988, Joseph G. Loesch, Bruce W. Hill, William H. Kreite Jr. Jan 1988

A Mark-Recapture Study Of Striped Bass In The Rappahannock River, Virginia Annual Report 1987-1988, Joseph G. Loesch, Bruce W. Hill, William H. Kreite Jr.

Reports

Internal anchor tags with external tubes were used to tag 3, 319 striped bass in the Fall of 1987 and 2,024 in the Spring of 1988 in the Rappahannock River. The total number tagged was adjusted to 3,170 and 1,973 by removing from consideration all fish that were at large less than a week. The available stock of striped bass in the Spring contained both young resident fish and mature nonresident fish which left the area of capture after spawning, presumably to migrate north in coastal waters. The exodus of the mature fish after spawning was responsible, in part, for …


A Documentation Of Virginia Trawl Surverys, 1955-1984, Listing Pertinent Variables: Date, Station Location, Gear, Vessel, Tow Direction, And Type Of Survey Volume I: Chesapeake Bay, Frank J. Wojcik, Willard A. Van Engel Jan 1988

A Documentation Of Virginia Trawl Surverys, 1955-1984, Listing Pertinent Variables: Date, Station Location, Gear, Vessel, Tow Direction, And Type Of Survey Volume I: Chesapeake Bay, Frank J. Wojcik, Willard A. Van Engel

Reports

No abstract provided.


Public Oyster Shoal Survey - Fall 1988, Bruce Barber, James Whitcomb Jan 1988

Public Oyster Shoal Survey - Fall 1988, Bruce Barber, James Whitcomb

Reports

This report summarizes data collected during 1988 in the Virginia portion of the Chesapeake Bay. The report focuses on the fall oyster survey in Virginia.


Oyster Shoal Survey - Spring 1988, James Whitcomb Jan 1988

Oyster Shoal Survey - Spring 1988, James Whitcomb

Reports

This report summarizes data collected during 1988 in the Virginia portion of the Chesapeake Bay. The report focuses on the spring oyster survey in Virginia.


Phytoplankton, Nutrients, Macroalgae And Submerged Aquatic Vegetation In Delaware's Inland Bays, 1985-1986, Benedict Estuarine Research Laboratory., Delaware Department Of Natural Resources And Environmental Control Jan 1988

Phytoplankton, Nutrients, Macroalgae And Submerged Aquatic Vegetation In Delaware's Inland Bays, 1985-1986, Benedict Estuarine Research Laboratory., Delaware Department Of Natural Resources And Environmental Control

Reports

Data were collected in each of the three program elements, Phytoplankton and Nutrients, Macroalgae and Submerged Aquatic Vegetation, indicate that Delaware's Inland Bays are highly eutrophic systems. ...


Comparative Analysis Of Sea Scallop Escapement/Retention And Resulting Economic Impacts, William D. Dupaul, Edward J. Heist, James E. Kirkley Jan 1988

Comparative Analysis Of Sea Scallop Escapement/Retention And Resulting Economic Impacts, William D. Dupaul, Edward J. Heist, James E. Kirkley

Reports

During the months of June and September 1988, gear experiments were conducted aboard the F/V Carolina Dawn and Carolina Capes. The primary objective of the experiments was to assess the technical efficiency and size selectivity of 3.5-inch ring dredges relative to the current commercially-used 3.0-inch ring dredges. Secondary objectives were to analyze the economic and regulatory ramifications of using 3.5-inch ring dredges to control the age-at-capture and enhance the yield-per- recruit.