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Full-Text Articles in Life Sciences

Phytoplankton Dynamics In The Very Low Salinity Region Of The James River Estuary, Virginia, U.S.A., Changho Moon Oct 1987

Phytoplankton Dynamics In The Very Low Salinity Region Of The James River Estuary, Virginia, U.S.A., Changho Moon

OES Theses and Dissertations

During summer and autumn discharge from the James River estuary, Virginia, was less than 120 m3sec-1. There was a peak phytoplankton biomass in the very low salinity region (defined as the location where surface salinity measured less than 0.5$ 0/00) and this peak represented five to ten times greater biomass than adjacent waters. The peak biomass occurred independent of the tidal state and the location of nutrient inputs. It disappeared during winter and spring, and nutrient limitation was not responsible for the low phytoplankton biomass, indicating there were physical, not chemical controlling factors.

The peak biomass …


Molting In The Mature Female Blue Crab, Callinectes Sapidus, Rathbun, Kirk J. Havens Oct 1987

Molting In The Mature Female Blue Crab, Callinectes Sapidus, Rathbun, Kirk J. Havens

OES Theses and Dissertations

The present study examines the hypothesis that mature female blue crabs, Callinectes sapidus, do not have a terminal anecdysis. Induced molting via eyestalk ablation, size frequency distributions and gonad and limb regeneration indices from field collected animals are used as indicators of potential post maturity molts.

Eyestalk ablation of mature females resulted in ecdysis approximately 51 days after ablation, indicating a physiological ability if mature females to complete ecdysis. Analysis of size frequency distributions indicates two distinct shifts from smaller to larger females, one in early spring and a second in early fall. While migration of larger females into …


An Annual Study Of Phytoplankton Composition And Associated Environmental Conditions Of Lake Trashmore, Virginia Beach, Virginia, Seba B. Sheavly Jul 1987

An Annual Study Of Phytoplankton Composition And Associated Environmental Conditions Of Lake Trashmore, Virginia Beach, Virginia, Seba B. Sheavly

Biological Sciences Theses & Dissertations

A 12 month study of Lake Trashmore was conducted on phytoplankton composition, inorganic nutrients and their seasonal associations. The dominant phytoplankton groups observed were diatoms, chlorophyceans and cyanobacteria. Phytoplankton assemblage patterns were coupled with pH, temperature, dissolved oxygen, nitrites and silicates. Diatoms dominated during periods of high nutrient concentrations, cooler temperatures and an unstable water column. Cyanobacteria forms dominated during periods of warmer temperatures, higher pH and decreased nitrogen and dissolved oxygen concentrations. A seasonal community shift occurred from cyanobacterial dominance to chlorophycean dominance when pH levels decreased. The lake is eutrophic based on indices of chlorophyll a concentrations, transparency …


Growth Potential Of Young Black Sea Bass, Centropristis Striata, In Artificial Environments, Joung Won Kim Jul 1987

Growth Potential Of Young Black Sea Bass, Centropristis Striata, In Artificial Environments, Joung Won Kim

OES Theses and Dissertations

The growth potential of the commercially important marine finfish, black sea bass (Centropristis striata), was examined for aquaculture under controlled conditions. The effect of food and body weight on growth was evaluated using juveniles and young black sea bass cultured with a natural diet and a commercial diet at various feeding levels.

Growth was affected by type of food, food consumption rate, and fish body weight. For fish having positive weight gain, absolute growth rate (gram/day) increased exponentially as food consumption rate (percent of body weight per day) and/or body weight increased. Instantaneous growth rate (percent of body weight per …


A Comparison Of Potential Fishing Methods Associated With Fish Aggregating Devices Off The Northeast Coast Of Puerto Rico, Alan M. Friedlander Jul 1987

A Comparison Of Potential Fishing Methods Associated With Fish Aggregating Devices Off The Northeast Coast Of Puerto Rico, Alan M. Friedlander

OES Theses and Dissertations

Six fish aggregating devices (FADs) were deployed in June and monitored through December 1986. Emphasis was placed on trolling, live-bait handlining and longlining.

There was a significant difference (x2 = 7.815, pCoryphaena hippurus) which made up 64.2% of the catch.

Handlining at night around inshore buoys for one boat yielded 82.7 kg per trip. Pelagic fish comprised 83.9% of the catch, with the majority (81.4%) being kingfish (Scomberomorous cavalla). Catch rates were 50% higher and the species diversity much greater on the FADs versus control during experimental nightfishing, but the difference was not significant.

Longlining resulted in 3.4 …


Tuna Fishery In The East Central Atlantic Region: The Feasibility Of Nigeria's Participation, Aderemi Olasupo Abioye Jan 1987

Tuna Fishery In The East Central Atlantic Region: The Feasibility Of Nigeria's Participation, Aderemi Olasupo Abioye

Theses and Major Papers

Tuna fishery is widely practiced in the east central Atlantic region by many fleets of different nationality. Most of the catch is taken by distant-water fleets. The new Law of the Sea convention, which gives coastal states an exclusive economic zone with outer limit of 200 miles, now allows the coastal states to make the most use of the living resources in their waters. The surplus shall be allocated to other states in the region and those traditionally fishing in the area before. Nigeria with a population of about 100 million people spends substantial foreign exchange annually on the importation …


An Analysis Of The Massachusetts Inshore Lobster Fishery, Peter Robertson Hoar Jan 1987

An Analysis Of The Massachusetts Inshore Lobster Fishery, Peter Robertson Hoar

Theses and Major Papers

The purpose of this thesis was to explore the limited entry alternative of fishery management by examining the history of a particular limited entry scheme: the Massachusetts inshore commercial lobster fishery license limitation law. A review was made of existing limited entry theory, followed by a description of limited entry programs extant in U.S. fisheries. The legislative and political histories of the Massachusetts lobster fishery limited entry program was then examined. The limited entry law was then analyzed by comparing what actually occurred with what is supposed to occur according to limited entry theory. A quantitative analysis of changes in …


A Multidisciplinary Analysis Of The Imposition Of Countervailing Duties On Canadian Groundfish Imports, Richard A. Pearson Jan 1987

A Multidisciplinary Analysis Of The Imposition Of Countervailing Duties On Canadian Groundfish Imports, Richard A. Pearson

Theses and Major Papers

This thesis provides a multidisciplinary analysis of the circumstances which surrounded the successful imposition of a countervailing duty on whole Canadian groundfish, and indicates what implications this action may have for the future. First, it will situate the countervailing duty investigation in terms of its relationship with U.S. statutes, and also with the Nation's international obligations. Then, the impact of the duty is examined to see how it might affect a potential free trade agreement with Canada. Similarly, the thesis projects what effect the duty will have in establishing a precedent, and assesses the likelihood of imposing similar duties on …


The Respiratory Response Of Busycon Canaliculatum (L) To Seasonal Variation Of Water Temperature, Salinity, And Oxygen, Harry Gregory Polites Jan 1987

The Respiratory Response Of Busycon Canaliculatum (L) To Seasonal Variation Of Water Temperature, Salinity, And Oxygen, Harry Gregory Polites

Dissertations, Theses, and Masters Projects

No abstract provided.


Identification And Distribution Of Urophycis (Gill) And Phycis (Artedi) Larvae And Pelagic Juveniles In The Middle Atlantic Bight, Bruce Henry Comyns Jan 1987

Identification And Distribution Of Urophycis (Gill) And Phycis (Artedi) Larvae And Pelagic Juveniles In The Middle Atlantic Bight, Bruce Henry Comyns

Dissertations, Theses, and Masters Projects

No abstract provided.


Population Structure Of The White Perch, Morone Americana, In Lower Chesapeake Bay As Inferred From Mitochondrial Dna Restriction Analysis, Brian W. Bowen Jan 1987

Population Structure Of The White Perch, Morone Americana, In Lower Chesapeake Bay As Inferred From Mitochondrial Dna Restriction Analysis, Brian W. Bowen

Dissertations, Theses, and Masters Projects

No abstract provided.


A Trophic Resource Analysis Of Dominant Benthic Microfauna Of The Lower Chesapeake Bay, Douglas Vernon Huggett Jan 1987

A Trophic Resource Analysis Of Dominant Benthic Microfauna Of The Lower Chesapeake Bay, Douglas Vernon Huggett

Dissertations, Theses, and Masters Projects

No abstract provided.


Potential Fish Egg Production By Mnemiopsis Leidyi Determined By Hydrography At The Chesapeake Bay Mouth, Harry D. Johnson Jan 1987

Potential Fish Egg Production By Mnemiopsis Leidyi Determined By Hydrography At The Chesapeake Bay Mouth, Harry D. Johnson

Dissertations, Theses, and Masters Projects

No abstract provided.


Studies Of Pipefish Foraging In Simulated Seagrass Habitats, Clifford H. Ryer Jan 1987

Studies Of Pipefish Foraging In Simulated Seagrass Habitats, Clifford H. Ryer

Dissertations, Theses, and Masters Projects

Laboratory experiments determined the effects of two levels of habitat complexity upon pipefish (Syngnathus fuscus) foraging for amphipods. Habitats were composed of equal densities of either narrow (low complexity) or wide (high complexity) leafed artificial seagrass. The response to habitat, as measured by rate of encounter with amphipods, probability of attack after encounter, probability of success after attack, and overall rate of amphipod consumption, was determined for combinations of two fish size classes and three amphipod size classes. Small fish did not experience visually inhibitive effects in either habitat, while large fish had their visual fields impinged upon in the …


Primary Production And Temporal Variation In The Macrophytic Community Of A Tidal Freshwater Swamp, Bryan Keith Fowler Jan 1987

Primary Production And Temporal Variation In The Macrophytic Community Of A Tidal Freshwater Swamp, Bryan Keith Fowler

Dissertations, Theses, and Masters Projects

No abstract provided.


A Comparison Of The Relative Sediment Transport Of Quartz And Aragonite Sand For Use As Beach Renourishment Materials In South Florida, Brian Lewis Lipsitz Jan 1987

A Comparison Of The Relative Sediment Transport Of Quartz And Aragonite Sand For Use As Beach Renourishment Materials In South Florida, Brian Lewis Lipsitz

HCNSO Student Theses and Dissertations

An evaluation of the relative rates of sediment transport of an oolitic aragonite sand and a quartz quarry sand as possible beach renourishment materials has been conducted. When comparing equal volumes, the aragonite experienced less transport than the quartz in both the longshore and in the onshore-offshore directions. When comparing equal size fractions, in sizes 0.35mm and smaller, aragonite was less transportable. The quartz was less transportable in the sizes greater than 0.35mm. This trend was observed in two separate experiments and is attributed to the effective density ratio of aragonite to quartz, dissimilarities in roundness and sphericity, and to …


Coliphage As An Indicator Of Fecal Pollution In Marine Waters: Assay, Validation, And Application, Donald S. Mccorquodale Jr. Jan 1987

Coliphage As An Indicator Of Fecal Pollution In Marine Waters: Assay, Validation, And Application, Donald S. Mccorquodale Jr.

HCNSO Student Theses and Dissertations

Escherichia coli, the preferred bacterial indicator for fecal pollution in fresh waters, does not conform to the concept of an indicator microorganism because it is rapidly killed or inactivated by seawater. This series of papers investigated the value of coliphage, a virus which infects E. coli, as an indicator of pollution in saline waters. In order to be an accurate indicator an organism must (1) be ubiquitous in wastewater, (2) survive and be detectable at least as long as the harmful organisms, and (3) be easy to isolate and identify.

A review of the literature determined that coliphage …


System Response Of A Nourished Beach In A Low-Energy Estuarine Environment, Gloucester Point, Virginia, Tracy Eanes Skrabal Jan 1987

System Response Of A Nourished Beach In A Low-Energy Estuarine Environment, Gloucester Point, Virginia, Tracy Eanes Skrabal

Dissertations, Theses, and Masters Projects

No abstract provided.


Life History Of The Goosefish, Lophius Americanus, Michael P. Armstrong Jan 1987

Life History Of The Goosefish, Lophius Americanus, Michael P. Armstrong

Dissertations, Theses, and Masters Projects

No abstract provided.