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Full-Text Articles in Life Sciences

Evaluation Of Automated Threshold Selection Methods For Accurately Sizing Microscopic Fluorescent Cells By Image-Analysis, Me Sieracki, Se Reichenbach, Kl Webb Nov 1989

Evaluation Of Automated Threshold Selection Methods For Accurately Sizing Microscopic Fluorescent Cells By Image-Analysis, Me Sieracki, Se Reichenbach, Kl Webb

VIMS Articles

The accurate measurement of bacterial and protistan cell biomass is necessary for understanding their population and trophic dynamics in nature. Direct measurement of fluorescently stained cells is often the method of choice. The tedium of making such measurements visually on the large numbers of cells required has prompted the use of automatic image analysis for this purpose. Accurate measurements by image analysis require an accurate, reliable method of segmenting the image, that is, distinguishing the brightly fluorescing cells from a dark background. This is commonly done by visually choosing a threshold intensity value which most closely coincides with the outline …


Effects Of Hypoxia And Anoxia On Survival, Energy Metabolism, And Feeding Of Oyster Larvae (Crassostrea Virginica, Gmelin), J Widdows, Rie Newell, Roger L. Mann Aug 1989

Effects Of Hypoxia And Anoxia On Survival, Energy Metabolism, And Feeding Of Oyster Larvae (Crassostrea Virginica, Gmelin), J Widdows, Rie Newell, Roger L. Mann

VIMS Articles

The tolerance of Crassostrea virginica larvae to anoxia increases with developmental stage and body size. Median mortality times range from 11 h for prodissoconch larvae of 82 micro m (shell length) to 51 h for pediveliger larvae of 3 12 micro m, and 150 h for juvenile oysters. Simultaneous calorimetry and respirometry showed that in response to declining oxygen tension (P02), the rates of heat dissipation and oxygen uptake by oyster larvae are maintained independent of PO2 down to low Pc values (2 kPa for prodissoconch larvae and 8 kPa for pediveliger and juveniles). Therefore, total energy metabolism is sustained …


A Mark-Recapture Study Of Striped Bass In The James River, Virginia : Annual Report 1988, Joseph G. Loesch, Bruce W. Hill Jun 1989

A Mark-Recapture Study Of Striped Bass In The James River, Virginia : Annual Report 1988, Joseph G. Loesch, Bruce W. Hill

Reports

EXECUTIVE SUMMARY

1. In the Spring 1988, 2,145 striped bass were tagged in the James River.

2. The mean size of striped bass tagged in 1988 (351.6 mm) was 117.9 mm smaller than mean size in 1987. The difference may be due to different locations and times of tagging.

3. The dominant age group in 1987 was the 1982 year class but in 1988 the dominant age group was the 1984 year class. This difference may also be accounted for by different locations and times of tagging.

4. The exodus of the mature fish out of the river after spawning …


Sediment Processes Monitoring Annual Report For Calendar Year 1988, Richard Wetzel, Bruce Neilson Jun 1989

Sediment Processes Monitoring Annual Report For Calendar Year 1988, Richard Wetzel, Bruce Neilson

Reports

No abstract provided.


Hypoxia In The Lower Rappahannock Estuary, Albert Y. Kuo, Mohamed Z. Moustafa Jun 1989

Hypoxia In The Lower Rappahannock Estuary, Albert Y. Kuo, Mohamed Z. Moustafa

Reports

There are several objectives to this study. The immediate objective is to collect a comprehensive and consistent set of field observations to better describe the hypoxic condition in the Rappahannock River. Other objectives can be classified as short and long term goals.

Long term: (1) Identify and quantify the processes contributing to the dissolved oxygen budget in deep waters, and explain the variabilities among the three Virginia major tributary estuaries. (2) Provide information for resource management so that the James River can be protected from hypoxic problems and, perhaps, the problems in the York and Rappahannock Rivers can be alleviated. …


Virginia's Recreational Marlin And Tuna Fishery 1983 -1988 : A Report To The Fishermen, Eleanor A. Bochenek, Nancy J. Chartier, Jon A. Lucy Jun 1989

Virginia's Recreational Marlin And Tuna Fishery 1983 -1988 : A Report To The Fishermen, Eleanor A. Bochenek, Nancy J. Chartier, Jon A. Lucy

Reports

No abstract provided.


Occurrence Of Indicators Of Fecal Pollution In Water And Sediment Of A Subestuary Impacted By Non-Point Pollution, Howard I. Kator, Martha Rhodes May 1989

Occurrence Of Indicators Of Fecal Pollution In Water And Sediment Of A Subestuary Impacted By Non-Point Pollution, Howard I. Kator, Martha Rhodes

Reports

No abstract provided.


Determination Of Marina Buffer Zones Using Simple Mixing And Transport Models : A Report To The Virginia State Dept. Of Health, Bureau Of Shellfish Sanitation As Part Of The Chesapeake Bay Initiatives Marine Pollution Abatement Initiative, John M. Hamrick, Bruce J. Neilson May 1989

Determination Of Marina Buffer Zones Using Simple Mixing And Transport Models : A Report To The Virginia State Dept. Of Health, Bureau Of Shellfish Sanitation As Part Of The Chesapeake Bay Initiatives Marine Pollution Abatement Initiative, John M. Hamrick, Bruce J. Neilson

Reports

This report describes the rationale, development and application of simple mixing and transport models for the determination of marina buffer zones and buffer zones for other point source discharges. Included in the report are two computer programs for implementation of the most general two dimensional transport model.


Geotechnical And Benthic Evaluation Of Sand Resources In The Lower Chesapeake Bay - Report 1: Thimble Shoal, Suzette M. Kimball, Linda C. Schaffner, Carl H. Hobbs Iii Apr 1989

Geotechnical And Benthic Evaluation Of Sand Resources In The Lower Chesapeake Bay - Report 1: Thimble Shoal, Suzette M. Kimball, Linda C. Schaffner, Carl H. Hobbs Iii

Reports

This report details the results of an exploration program to delineate reserves containing quantities of beach quality sand suitable for emplacement on public recreational beaches in the City of Hampton.


Feasibility Of Crab Meal Processing In The Chesapeake Bay Region Ii: An Integrated Economic Analysis For Hampton/Newport News, Virginia, Phillip R. Grulich, William D. Dupaul Feb 1989

Feasibility Of Crab Meal Processing In The Chesapeake Bay Region Ii: An Integrated Economic Analysis For Hampton/Newport News, Virginia, Phillip R. Grulich, William D. Dupaul

Reports

The crab waste problem in Virginia and Maryland has been well documented by past research efforts, (Hatem, 1980) (Murray and DuPaul 1981) (Cathcart et, al.1984). Murray and DuPaul (1981) documented both the magnitude and location of the problem in Maryland and Virginia. Their analysis provided a description of the total waste disposal problem in the Bay and pinpointed specific trouble spots. The report provided enterprise budgets for three locations; Hampton, Virginia, Crisfield, Maryland, and Cambridge, Maryland. These locations were chosen because of their proximity to crab processors and their ability to produce sufficient quantities of crab waste to make a …


Fact Sheet: Aviation Services, College Of William And Mary, Virginia Institute Of Marine Science Jan 1989

Fact Sheet: Aviation Services, College Of William And Mary, Virginia Institute Of Marine Science

Miscellaneous

Brochure describing the features and specifications of the 1954 DeHavilland Beaver aircraft, acquired on loan from the U.S. Navy in late1975, used for aerial photography, reconnaissance, observation and transport in support of the Institute's research mission.

The brochure is undated, 1989 is estimated.

Additional background information on the airplane available p.1 : https://scholarworks.wm.edu/miscellaneous/19/


The College Of William And Mary, School Of Marine Science, 1989-90 Program, College Of William And Mary, School Of Marine Science Jan 1989

The College Of William And Mary, School Of Marine Science, 1989-90 Program, College Of William And Mary, School Of Marine Science

Miscellaneous

Catalog for the Graduate program from the School of Marine Science at the College of William and Mary for the listed academic year.


Ingestion Of Gametes By Protists: Fate Of Surplus Reproductive Energy In The Sea, Hm Galvao, At Fritz, R Schmaljohann Jan 1989

Ingestion Of Gametes By Protists: Fate Of Surplus Reproductive Energy In The Sea, Hm Galvao, At Fritz, R Schmaljohann

VIMS Articles

No abstract provided.


Biological Control Of Crab Predation On Hard Clams Mercenaria Mercenaria (Linnaeus, 1758) By The Toadfish Opsanus Tau (Linnaeus) In Tray Cultures, Robert Bisker, Michael Castagna Jan 1989

Biological Control Of Crab Predation On Hard Clams Mercenaria Mercenaria (Linnaeus, 1758) By The Toadfish Opsanus Tau (Linnaeus) In Tray Cultures, Robert Bisker, Michael Castagna

VIMS Articles

Oyster toadfish Opsanus tau (Linne) were tested as biological controls of crab predation on juvenile hard clams Mercenaria mercenaria (Linne) in trays with crushed stone aggregate. Clam survival after 34 weeks was 69.5% in the presence of toadfish and 2.3% in trays without toadfish. Toadfish reduced the total number of crabs (mud crabs and blue crabs). Crabs in trays with toadfish present had smaller carapace widths.


Predation By The Oyster Toadfish Opsanus Tau (Linnaeus) On Blue Crabs And Mud Crabs, Predators Of The Hard Clam Mercenaria Mercenaria (Linnaeus, 1758), Robert Bisker, Mary Gibbons, Michael Castagna Jan 1989

Predation By The Oyster Toadfish Opsanus Tau (Linnaeus) On Blue Crabs And Mud Crabs, Predators Of The Hard Clam Mercenaria Mercenaria (Linnaeus, 1758), Robert Bisker, Mary Gibbons, Michael Castagna

VIMS Articles

The oyster toadfish, Opsanus tau (Linne), reduces predation by xanthid and portunid crabs on juvenile hard clams, Mercenaria mercenaria (Linne), in field cultures. This study examined the influence of size and species on the predator-prey relationship between toadfish and crabs. The mud crabs Eurypanopeus depressus (Smith), Neopanope sayi (Smith), and Panopeus herbstii Milne Edwards of 5-40 mm carapace width and blue crabs Callinectes sapidus Rathbun of 77-105 mm carapace width were offered to toadfish of 70-322 mm total length. Toadfish predation rates on mud crabs were higher with increasing toadfish size and lower with increasing crab size. Toadfish injured or …


Autotrophic Picoplankton Dynamics In A Chesapeake Bay Sub-Estuary, Rt Ray, Lw Hass, Me Sieracki Jan 1989

Autotrophic Picoplankton Dynamics In A Chesapeake Bay Sub-Estuary, Rt Ray, Lw Hass, Me Sieracki

VIMS Articles

No abstract provided.


Striped Bass Research, Virginia : Estimation Of Juvenile Striped Bass Relative Abundance, Annual Report 1988, James A. Colvocoresses Jan 1989

Striped Bass Research, Virginia : Estimation Of Juvenile Striped Bass Relative Abundance, Annual Report 1988, James A. Colvocoresses

Reports

The Virginia Institute of Marine Science (VIMS) has conducted a juvenile striped bass seine survey during the years from 1967 through 1973 and from 1980 through the present, with the primary objective of monitoring the relative annual recruitment success of juvenile striped bass in the spawning and nursery areas of Lower Chesapeake Bay. The survey was funded during it's initial period by the U.S. Fish and Wildlife Service and then reinstated in 1980 with funding from the National Marine Fisheries Service under the Emergency Striped Bass Study program. Commencing with the 1988 annual survey reported herein, support of the program …


Public Oyster Shoal Survey - Spring 1989, Bruce Barber Jan 1989

Public Oyster Shoal Survey - Spring 1989, Bruce Barber

Reports

This report summarizes data collected during 1989 in the Virginia portion of the Chesapeake Bay. The report focuses on the spring oyster survey in Virginia.


Striped Bass Research, Virginia: Characterization Of Virginia's Striped Bass Commercial Fisheries Annual Report 1988-89, Bruce W. Hill, Joseph G. Loesch Jan 1989

Striped Bass Research, Virginia: Characterization Of Virginia's Striped Bass Commercial Fisheries Annual Report 1988-89, Bruce W. Hill, Joseph G. Loesch

Reports

The research reported herein (and in the 1982 through 1987 annual reports) is directly related to Priority III stated in the "Action Plan" (p. 15) of the Emergency Striped Bass Study (Anadromous Fish Conservation Act Amendment, Public Law 96-118). The amendment was the result of a decline in striped bass (Marone saxatilis) landings from Maine to North Carolina since the mid-1970's. This report summarizes the results of the fall 1988 and spring 1989 sampling period and compares these results with the previous work.


A Documentation Of Virginia Trawl Surverys, 1955-1984, Listing Pertinent Variables: Date, Station Location, Gear, Vessel, Tow Direction, And Type Of Survey Volume Iv: Rappahannock River, Frank J. Wojcik, Willard A. Van Engel Jan 1989

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

Reports

No abstract provided.


Develop A Fishery Stock Identification Laboratory And Identify Coastal And Estuarine Stocks That Are Dependent On The Chesapeake Bay And Its Tributaries, Brian W. Meehan Jan 1989

Develop A Fishery Stock Identification Laboratory And Identify Coastal And Estuarine Stocks That Are Dependent On The Chesapeake Bay And Its Tributaries, Brian W. Meehan

Reports

Final report for a cooperative agreement between the Northeast Fisheries Center and the Virginia Institute of Marine Science to determine short- and long-term factors affecting mortality and recruitment of key commercial and recreational species, including fishing mortality and both natural and man-induced environmental impacts on mortality and recruitment, project 3.0."

Includes M.S. thesis by Carol Furman- Mitochondrial DNA variation in striped bass, Morone saxatilis, from the Rappahannock River, Virginia.


A Mark-Recapture Study Of Striped Bass In The Rappahannock River, Virginia Annual Report 1988-1989, Joseph G. Loesch, Bruce W. Hill Jan 1989

A Mark-Recapture Study Of Striped Bass In The Rappahannock River, Virginia Annual Report 1988-1989, Joseph G. Loesch, Bruce W. Hill

Reports

A total of 3,892 striped bass were tagged and released in the Fall 1988 and 1,316 fish in the Spring 1989 on the Rappahannock River.

In the Fall, 77.6% of the tagged striped bass were less than 400 mm FL. In contrast, 81.5% of the fish were 400 mm FL or greater in the Spring.

The available striped bass stock in the Fall is more vulnerable to fishing than is the available stock in the Spring. Recaptures per net day of tagged striped bass in pound nets in the Fall 1987 were seven times greater than in the Spring 1988, …


A Comparison Of The Utermohl And Epifluorescent Microscopic Techniques For Quantifying Natural Picophytoplankton : Final Report, Leonard W. Haas, Harold G. Marshall Jan 1989

A Comparison Of The Utermohl And Epifluorescent Microscopic Techniques For Quantifying Natural Picophytoplankton : Final Report, Leonard W. Haas, Harold G. Marshall

Reports

The phytoplankton monitoring program in the Virginia portion of the Chesapeake Bay was initiated in July 1985. A total of 13 stations (7 in the lower Chesapeake Bay and 6 in the major trtbutaries) are sampled on a regular basis to quantify phytoplankton (Birdsong et al., 1987; 1988). A primary objective of the monitoring program is to document longterm trends in phytoplankton abundance and species composition and use this information as one means of evaluating the effectiveness of pollution abatement strategies, particularly related to the reduction of nutrients to the Chesapeake Bay.

The philosophy of monitoring programs is to consistently …


Status Of The Public Oyster Fishery Of Virginia - Fall 1989, Bruce Barber Jan 1989

Status Of The Public Oyster Fishery Of Virginia - Fall 1989, Bruce Barber

Reports

This report summarizes data collected during 1989 in the Virginia portion of the Chesapeake Bay. The report focuses on the fall oyster survey in Virginia.


Striped Bass Research, Virginia - Annual Report 1988-89, Virginia Institute Of Marine Science Jan 1989

Striped Bass Research, Virginia - Annual Report 1988-89, Virginia Institute Of Marine Science

Reports

The research reported herein (and in the 1982 through 1987 annual reports) is directly related to Priority III stated in the "Action Plan" (p. 15) of the Emergency Striped Bass Study (Anadromous Fish Conservation Act Amendment, Public Law 96-118). The amendment was the result of a decline in striped bass (Morone saxatilis) landings from Maine to North Carolina since the mid-1970's. This report summarizes the results of the Fall 1988 and Spring 1989 sampling periods and compares these results with the previous work.


Striped Bass Research, Virginia - Annual Report 1987-88, Virginia Institute Of Marine Science Jan 1989

Striped Bass Research, Virginia - Annual Report 1987-88, Virginia Institute Of Marine Science

Reports

The research reported herein is directly in response to priorities established in the "Action Plan" of the Emergency Striped Bass Study (the Chafee Amendment (PL 96-118) of the Anadromous Fish Conservation Act (PL 89 -304 )) . The Amendment was the result of a decline in striped bass landings along the Atlantic Coast that began in the mid-1970's. The Virginia Institute of Marine Science (VIMS) had previously conducted a juvenile striped bass seining program from 1967 through 1973 which was discontinued at that point due to a loss of funding. The program was reinstated in 1980 with funding from the …